251ISSN 0041-6436

An international journal of forestry and forest industries Vol. 70 2019/1

FORESTS: NATURE-BASED SOLUTIONS FOR WATER Forest and Water Programme

The FAO Forest and Water Programme this vision by facilitating the sharing envisions a world in which resilient of knowledge and experiences, forest landscapes are managed developing the capacity of forest, e ectively to provide sustainable land and water managers to manage water ecosystem services. In the forest–water nexus, and collaboration with partners from the providing tools to support forest and water sectors, it supports decision-making. countries and stakeholders in realizing

More information: www.fao.org/in-action/forest-and- water-programme

Unasylva is published in English, French and Spanish. Subscriptions can be obtained by Cover: Aerial view of a village near Phang sending an e-mail to [email protected]. Subscription requests from institutions (e.g. libraries, Nga Bay, Thailand. Forests and water have companies, organizations and universities) rather than individuals are preferred in order to always been inextricably entwined. make the journal accessible to more readers. All issues of Unasylva are available online free of © iStock.com/Oleh Slobodeniuk charge at www.fao.org/forestry/unasylva. Comments and queries are welcome at [email protected] 251ISSN 0041-6436

An international journal of forestry and forest industries Vol. 70 2019/1

Editor: A. Sarre Editorial Advisory Board: N. Berrahmouni, J. Campbell, P. Csoka, J. Fox, H. Abdel Hamied, D. Contents Hewitt, T. Hofer, H. Ortiz, L. Pina, E. Springgay, A. Taber, S. Wertz, Xia, Z., E. Yazici, Zhang, D. Editorial 2 Emeritus Advisers: J. Ball, I.J. Bourke, C. Palmberg-Lerche, L. Russo E. Springgay Proofreader: Jana Gough Forests as nature-based solutions for water 3 Designer: Roberto Cenciarelli D. Ellison, L. Wang-Erlandsson, R. van der Ent and M. van Noordwijk The designations employed and the presentation of material Upwind forests: managing moisture recycling for in this information product do not imply the expression of any opinion whatsoever on the part of the Food and Agriculture nature-based resilience 14 Organization of the United Nations (FAO) concerning the legal or development status of any country, territory, city or area or A.D. del Campo, M. González-Sanchis, U. Ilstedt, A. Bargués-Tobella of its authorities, or concerning the delimitation of its frontiers or boundaries. The mention of specific companies or products and S. Ferraz of manufacturers, whether or not these have been patented, does not imply that these have been endorsed or recommended Dryland forests and agrosilvopastoral systems: water at the core 27 by FAO in preference to others of a similar nature that are not mentioned. M. Gustafsson, I. Creed, J. Dalton, T. Gartner, N. Matthews, J. Reed, The views expressed in this information product are those of L. Samuelson, E. Springgay and A. Tengberg the author(s) and do not necessarily reflect the views or policies Gaps in science, policy and practice in the forest–water nexus 36 of FAO. ISBN 978-92-5-131910-9 R. Lindsay, A. Ifo, L. Cole, L. Montanarella and M. Nuutinen © FAO, 2019 Peatlands: the challenge of mapping the world’s invisible stores of carbon and water 46 D.W. Hallema, A.M. Kinoshita, D.A. Martin, F.-N. Robinne, M. Galleguillos, Some rights reserved. This work is made available under S.G. McNulty, G. Sun, K.K. Singh, R.S. Mordecai and P.F. Moore the Creative Commons Attribution-NonCommercial- ShareAlike 3.0 IGO licence (CC BY-NC-SA 3.0 IGO; https:// Fire, forests and city water supplies 58 creativecommons.org/licenses/by-nc-sa/3.0/igo/legalcode). L. Spurrier, A. Van Breda, S. Martin, R. Bartlett and K. Newman Under the terms of this licence, this work may be copied, redistributed and adapted for non-commercial purposes, Nature-based solutions for water-related disasters 67 provided that the work is appropriately cited. In any use of this work, there should be no suggestion that FAO endorses FAO Forestry 75 any specific organization, products or services. The use of the FAO logo is not permitted. If the work is adapted, then it must be licensed under the same or equivalent Creative Commons World of Forestry 76 licence. If a translation of this work is created, it must include the following disclaimer along with the required citation: “This translation was not created by the Food and Agriculture Books 78 Organization of the United Nations (FAO). FAO is not responsible for the content or accuracy of this translation. The original [Language] edition shall be the authoritative edition.” Disputes arising under the licence that cannot be settled amicably will be resolved by mediation and arbitration as described in Article 8 of the licence except as otherwise provided herein. The applicable mediation rules will be the mediation rules of the World Intellectual Property Organization http://www.wipo.int/amc/en/mediation/rules and any arbitration will be conducted in accordance with the Arbitration Rules of the United Nations Commission on International Trade Law (UNCITRAL). Third-party materials. Users wishing to reuse material from this work that is attributed to a third party, such as tables, figures or images, are responsible for determining whether permission is needed for that reuse and for obtaining permission from the copyright holder. The risk of claims resulting from infringement of any third-party-owned component in the work rests solely with the user. Sales, rights and licensing. FAO information products are available on the FAO website (www.fao.org/publications) and can be purchased through [email protected]. Requests for commercial use should be submitted via: www. fao.org/contact-us/licence-request. Queries regarding rights and licensing should be submitted to: [email protected]. EDITORIAL

ater – clean, drinkable water – is likely to be one of relationship between forests and water) in policies and practice. the most limiting resources in the future, given the Managing this nexus will be crucial for achieving many of the growing global population, the high water demand Sustainable Development Goals, but it requires taking a landscape Wof agricultural production systems and urban centres, and the approach. The ability to do this suffers from a lack of knowledge confounding effects of climate change. We need to manage water about the factors that regulate the multiple functions of landscapes, wisely – efficiently, cost-effectively and equitably – if we are to their interactions, and, ultimately, their effects on water users. avoid the calamity of a lack of usable water. The authors describe opportunities to address the forest–water Forested watersheds provide an estimated 75 percent of the nexus at the landscape scale, and they make recommendations world’s accessible freshwater resources, on which more than half for research to help fill the gaps in knowledge. the Earth’s people depend for domestic, agricultural, industrial Lindsay et al. make the case for much more policy attention on and environmental purposes. Sustainable forest management is peatlands, which, they say, are often unrecognized or ignored and essential, therefore, for good water management, and it can pro- therefore subject to widespread drainage and land-use conversion. vide “nature-based solutions” for many water-related challenges. Yet peatlands contain huge stores of carbon and their destruction This edition of Unasylva explores the challenges in realizing or mismanagement, therefore, could add substantially to global the potential. warming. For example, even a shallow peat (30 cm deep) contains In her article, Springgay explains that nature-based solutions more carbon than does primary tropical rainforest. Peatlands are in water management involve the management of ecosystems also huge freshwater reservoirs and their loss could have major (forested or otherwise) to mimic or optimize natural processes in implications for the sustainability of water supplies. Part of the the provision and regulation of water. In many parts of the world problem in gaining more recognition for peatlands is that they today, water management relies largely on “grey” infrastructure can be difficult to identify, and the authors provide a simple test; involving the use of concrete and steel. A move towards nature- they also make recommendations for policymakers on how to based solutions, says Springgay, requires a transformative shift in tackle this substantial but largely hidden challenge. thinking in which forests and other ecosystems are viewed and Hallema and co-authors look at the implications of chang- managed as freshwater regulators. She makes several recommen- ing forest fire regimes for forest and water management. The dations to facilitate the transition towards “green” infrastructure increasing occurrence of extreme wildfires is threatening the in water management. capacity of forests to deliver clean water. The authors say that In their article, Ellison et al. present startling findings on the developing cost-effective strategies for managing fire and water role of forests in multiplying the oceanic supply of freshwater in light of climate change, increasing urbanization and other through moisture recycling (in which rainfall is returned to the trends requires a better understanding of the regional impacts and atmosphere through evapotranspiration, making it available interactions of fire. Forests that are important for water supply downwind to fall again as rain). Forests, say the authors, exhibit but at risk of extreme wildfire need to be identified and actively more intense moisture recycling than non-forest land cover, managed, requiring the involvement of forest managers, hydrolo- partly because of their larger water-storage potential, which, in gists, wildfire scientists, public-health specialists and the public. turn, enables them to return rainfall to the atmosphere even in Finally, Spurrier et al. look at the crucial role of mangroves in dry periods. Mapping the sources and sinks of precipitation and reducing the risk of disaster for millions of vulnerable coastal evaporation can indicate where forest restoration efforts will people. Despite their importance, mangroves continue to decline be most effective in maximizing moisture recycling for drier in extent, and climate change and other pressures threaten them areas downwind. There is a desperate need, say the authors, to further. To help maintain the disaster-risk-reduction role of man- redesign institutional frameworks to take into account long- groves and other natural (or green) infrastructure, the authors distance forest–water relationships and their feedback effects recommend the use of adaptive frameworks and decision-support on water availability. tools that enable managers to integrate and continuously update Del Campo and co-authors present three case studies to show projections of climate-change risk, land use and human population how “water-centred” management approaches can increase the growth. resilience of dryland forests in the face of climate change. For Forests and water have always been inextricably entwined, example, judicious management of Aleppo pine forest in a dry and forest managers have always needed to consider hydrology region of Spain can increase tree growth and vigour and protect in their management decisions. But as resources become more soils while adding to catchment water budgets and downstream constrained and water demand grows ever greater, water manage- water flows. Such “ecohydrological-based forest management” ment will inevitably come even more to the fore in forest-related can increase water availability in water-limited environments decision-making. Recognizing the importance of the forest–water and therefore also socio-ecological resilience. nexus is the first step in building it into institutional processes Gustaffson and co-authors look at gaps in the knowledge and finding forest-based solutions for water. required to fully incorporate the forest–water nexus (i.e. the 3 © FAO/DANIEL HAYDUK Forests as nature-based solutions for water

E. Springgay

A transformation is needed from rowing populations and increasing approaches to water management are conventional forest management industrialization, urban develop- inadequate for ensuring the well-being approaches to nature-based ment and demand for food and of human populations, biodiversity and solutions that make water-related Gconsumer goods have led to large-scale ecosystems. ecosystem services the primary land-cover and land-use change globally, An estimated 65 percent of water fall- objective. which has, in turn, caused hydrological ing on land is either stored within soil or changes. It is also increasingly apparent evaporated from soil and plants (Oki and that much of the human-made grey-water Kanae, 2006), with 95 percent of the soil infrastructure,1 such as dams, pipes, ditches water stored within or above groundwater and pumps, has contributed to global zones (Bockheim and Gennadiyev, 2010). pro­blems and that business-as-usual Therefore, terrestrial ecosystems are important for land–water–energy balances, influencing soil water and atmospheric 1 Grey infrastructure generally refers to engi- neering projects that use concrete and steel, moisture availability and thus affecting green infrastructure depends on plants and eco­ systems, and blue infrastructure combines green Elaine Springgay is Forestry Officer at the FAO spaces with good water management (Sonneveld Above: Forests as a nature-based solution Forestry Department, Rome, Italy. et al., 2018). for water, United Republic of Tanzania

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climate (Huntington, 2006; Ellison et al., to achieve the social, economic and water for human consumption, industry 2017; Creed and van Noordwijk, 2018). All environmental goals embedded in these; and the environment. forests influence water (FAO, 2018b), from it is essential, therefore, to strategically Land-use decisions can have significant cloud forests and tree-covered wetlands integrate natural solutions, including consequences for water resources, com- upstream to dryland and coastal forests green and blue infrastructure, into overall munities, economies and environments downstream. It has been estimated that management approaches. The integration in distant (downstream and downwind) forested watersheds provide 75 percent of of nature-based solutions shows promise locations. The loss of natural forests may the world’s accessible freshwater resources for addressing water scarcity through increase water yields in the short term and that more than half the Earth’s popula- supply-side management, particularly by but have long-term negative impacts on tion is dependent on these water resources increasing water quality and groundwater water quantity and quality. For example, for domestic, agricultural, industrial and recharge, which ultimately is essential for evapotranspiration from the Amazon River environmental purposes (Millennium sustainable food production, improved and Congo River basins is a major source Ecosystem Assessment, 2005). Forests are human settlements, access to water supply of precipitation (around 50–70 percent) sometimes referred to as natural infrastruc- and sanitation, water-related risk reduc- in the Rio de la Plata basin and the Sahel, ture, and their management can provide tion, and building resilience to climate respectively (Van der Ent et al., 2010; “nature-based solutions” for a range of variability and change (UNWWDR, 2018). Ellison et al., 2017). Large-scale forest water-related societal challenges. This It is estimated that USD 10 trillion will loss and land conversion affect these article explores that potential. need to be invested in grey infrastructure natural processes, reducing cloud cover between 2013 and 2030 for adequate and precipitation downwind (Ellison et FORESTS: NATURAL water management (Dobbs et al., 2013). al., 2017; Creed and van Noordwijk, 2018). INFRASTRUCTURE FOR WATER Nature-based solutions could reduce this Forest restoration and tree planting will Nature-based solutions are actions that investment burden while also improving likely improve water quality, with the protect, sustainably manage and restore economic, social and environmental out- impacts of such interventions depend- natural and modified ecosystems in ways comes. Nearly USD 24 billion is estimated ing on species, management regime and that effectively and adaptively address to have been spent on green infrastructure temporal and spatial scale. It is estimated societal challenges and deliver benefits for water in 2015, benefiting 487 million that land conservation and restoration, for human well-being and biodiversity hectares of land (Bennet and Ruef, 2016). including forest protection, reforestation (Cohen-Shacham et al., 2016). In water Paying greater attention to landscape man- and agroforestry, could lead to a reduc- management, nature-based solutions agement, including integrated watershed tion of 10 percent or more in sediments involve the management of ecosystems management, land protection, reforestation and nutrients in watersheds (Abell et al., to mimic or optimize natural processes, and riparian restoration, could reduce the 2017). Care is needed, however, to ensure such as vegetation, soils, wetlands, water operational and maintenance costs of that achieving water-quality goals does bodies and even groundwater aquifers, grey infrastructure (Echavarria et al., not result in unacceptable trade-offs with for the provision and regulation of water. 2015; Box 1). water yield. The adoption of nature-based solutions In addition to their water-related eco­ for water requires a transformative shift in The role of forests in hydrology system services, forests provide habitat for thinking from demand- to supply-oriented All forests affect hydrology and so, there- fish and other aquatic species, which, in water management and planning, in which fore, does their management. Forests turn, play roles in ensuring the function- crucial ecosystems such as forests are seen and trees use water and provide many ality of these ecosystems. The quantity, not only as users but also as regulators of provisioning, regulating, supporting and quality, temperature and connectivity of fresh water. cultural ecosystem services. Forested water resources influence fish populations Nature-based solutions have gained areas and landscapes with trees, there- and aquatic biodiversity. Changes in these attention in recent years because of their fore, are integral components of the water factors can affect species richness, even- potential for addressing water scarcity cycle, regulating streamflow, fostering ness and endemism, thus influencing the and contributing to the achievement of the groundwater recharge and contributing biodiversity and food systems of dependent Sustainable Development Goals (SDGs), to atmospheric water recycling, including populations. the Paris Agreement on climate change, cloud generation and precipitation through Many fish and other aquatic organisms the Sendai Framework for Disaster Risk evapotranspiration. Forested areas and are sensitive to ecosystem degradation, Reduction, the Aichi Biodiversity Targets, landscapes with trees also act as natural such as through eutrophication, habitat and other international commitments. Grey filters, reducing soil erosion and water degradation and fragmentation, acidifi- infrastructure alone will be insufficient sedimentation, thus providing high-quality cation, and changes in temperature and

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Box 1 Forest management: nature-based solution for urban water supply

Ninety percent of major cities rely on forested watersheds for their water supply (McDonald and Shemie, 2014), with one-third of the world’s largest cities, including Bogotá, Johannesburg, New York, Tokyo and Vienna, obtaining a large proportion of their drinking water from pro- tected forest areas (Dudley and Stolton, 2003). Source-water protection, including through forest restoration and trees on agricultural land, could improve water quality for more than 1.7 billion people living in cities at a cost of less than USD 2 per person per year (which would be offset by savings from reduced water treatment) (World Bank, 2012; Abell et al., 2017). For example, a forest-based initiative to reduce water pollution from agriculture has saved the City of New York from the need to install a treatment plant (at an estimated cost of USD 8 billion–10 billion), as well as an additional USD 300 million per year in operational and maintenance costs. New York City has the largest unfiltered water supply in the United States of America (Abell et al., 2017). Similarly, the estimated water conservation value of Beijing’s forests is USD 632 million (approximately USD 689 per ha) per year (Biao et al., 2010). Forests are used as nature-based solutions for water-related natural hazards. In Peru’s Pacific Coast water basin, where an estimated two-thirds of historical tree cover has been lost (WRI, 2017), integrating green and grey infrastructure could reduce Lima’s dry-season deficit by 90 percent, and this would be more cost-effective than implementing grey infrastructure alone (Gammie and de Bievre, 2015). Likewise, local forest restoration is being used in Malaga, Spain, to mitigate flood risk. As urban populations grow, ecosystems and their services will increasingly be pushed to their limits (Kalantari et al., 2018). This is particularly true in the fastest-growing cities – small and medium-sized cities that are undergoing rapid and mostly unplanned expansions of their urban areas but which may need to rely increasingly on watersheds for water supply. Of the three fastest-growing cities in Africa and Asia (based on United Nations data), an unpublished FAO review has determined that only Kampala, Uganda, acknowledges the water-related services provided by forests. The potential of forest management to provide nature-based solutions to mitigate some of the challenges of urban development needs to be considered in spatial planning and management strategies (Kalantari et al., 2018). To grow sustainably, cities will need to play active roles in protecting the water sources on which they depend.

Children cross a river in the Philippines. It is important to manage forests © FAO/JAKE SALVADOR and trees with water ecosystem services in mind and to maximize the forest benefits for water

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climate (FAO, 2018a). For example, the six in the past 100 years, in direct cor- health and well-being, the environment number of threatened and endangered relation with population growth (Wada et and sustainable development (Veolia and freshwater species has increased due to the al., 2016); water consumption continues IFPRI, 2015). For example, an estimated poor health of inland water systems (FAO, to grow at about 1 percent per year (FAO, 80 percent of all industrial and municipal 2018a). The Living Planet Index indicates undated). The global population is pro- wastewater is released into the environment an 83 percent decline in freshwater species jected to increase from 7.7 billion in 2017 to without treatment (WWAP, 2017). Changes populations since 1970 (WWF, 2018). 9.4 billion–10.2 billion people in 2050, with in water sediment loads and temperature Forests and trees can help mitigate minor two-thirds living in cities (United Nations, can significantly affect fish populations to moderate flooding events, control ava- 2018). Global water demand is projected and aquatic biodiversity, which may fur- lanches, combat desertification, and abate to rise by 20–30 percent by 2050, due to ther affect dependent food chains and food storm surges. For example, mangrove for- population growth, associated economic security (FAO, 2018a). ests act as protective shields against wind development, changing consumption pat- Changes in land cover and use, population and wave erosion, storm surges and other terns, land-use change and climate change, growth, and the frequency and intensity of coastal hazards (FAO, 2007; Nagabhatla, among other factors (Burek et al., 2016; extreme events associated with a changing Springgay and Dudley, 2018), and trees in W WA P, 2 018). climate increase the risk of water-related drylands help abate soil erosion and drought Under a business-as-usual scenario, the disasters. Since 1992, floods, droughts and by capturing fog water, reducing surface world is projected to face a 40 percent water storms have affected 4.2 billion people and water runoff and promoting groundwater deficit by 2050 (WWAP, 2015). Domestic caused USD 1.3 trillion in damage world- recharge (Ellison et al., 2017). Changes in water use will increase significantly in wide (UNESCAP/UNISDR, 2012). Floods land use – such as large-scale deforesta- all regions, particularly Africa and Asia, have become more frequent, increasing tion or, conversely, forest restoration – can where domestic demand is expected to from an average of 127 events per year influence the resilience of landscapes in triple, and in Central and South America, in 1995–2004 to 171 events per year in the face of water-related natural hazards. where estimated future demand is double 2005–2014; floods have accounted for 47 It is important, therefore, to manage current withdrawals (Burek et al., 2016). At percent of all weather-related disasters forests and trees with water ecosystem the same time, food demand is expected to since 1995 and affected 2.3 billion people services in mind and to maximize the forest increase by 60 percent, requiring more land (CRED and UNISDR, 2015). benefits for water and mitigate negative for food production and causing impacts It is estimated that floods, droughts and impacts. A range of management deci- on soil and water resources that likely will storms result in average global losses sions, such as species selection, stocking lead to further degradation (FAO, 2011b). of USD 86 billion per year across all densities, and location in the landscape, Meanwhile, less than 1 percent of the economic sectors, with Africa and Asia can have important effects on hydrology. total available freshwater is allocated for most affected in terms of deaths, dam- Managing forests for multiple benefits is maintaining the health of ecosystems that aged communities and economic losses. the foundation of sustainable forest man- serve as natural infrastructure for water The cost of floods, droughts and storms agement, but it requires an understanding (Boberg, 2005; Nagabhatla, Springgay and worldwide is expected to escalate to USD and recognition of trade-offs. For example, Dudley, 2018). 200 billion–400 billion per year by 2030 fast-growing exotic species planted for bio- Approximately 80 percent of the world’s (OECD, 2015). mass and carbon sequestration may have a population suffers from moderate to severe The impacts of disasters could be miti- positive impact on water quality but could water scarcity (Mekonnen and Hoekstra, gated if land and forest conversion, urban greatly reduce water supply. Reducing tree 2016). Nearly half the global population is expansion and planning, and the intensifica- densities, prolonging rotation cycles and already living in areas with potential water tion of food production take ecological conserving native forests in riparian buffer scarcity at least one month per year, and it functions into account and aim to improve zones could mitigate these negative effects. is estimated that this will increase to 4.8 – rather than degrade – ecosystem services. billion–5.7 billion people – more than half 2 According to the Ramsar Convention on Wet- WATER: A GLOBAL CHALLENGE the projected global population – by 2050 lands (2016), wetlands “are areas of marsh, fen, Davidson (2014) estimated that up to 87 (Burek et al., 2016). peatland or water, whether natural or artificial, percent of all wetlands,2 including tree- Water pollution has worsened in almost permanent or temporary, with water that is static or flowing, fresh, brackish or salt, including areas covered wetlands and peatlands, have been all rivers in Africa, Asia and Latin of marine water the depth of which at low tide lost worldwide since the eighteenth cen- America since the 1990s (UNEP, 2016; does not exceed six metres”. They “may also tury; up to 71 percent of all wetlands have WWAP, 2018), and the degradation of incorporate riparian and coastal zones adjacent to the wetlands, and islands or bodies of marine been destroyed since 1900. Global water water resources is expected to increase water deeper than six metres at low tide lying consumption has increased by a factor of in the next decades, threatening human within the wetlands”.

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A forest park in Hanoi, Viet Nam. Forests and water go arm-in-arm

Box 2 Incentivizing forest–water management Payment for ecosystem services (PES) schemes constitute a potential incentive mechanism for better environmental management. Applied to forest–water management, PES schemes require service “buyers” (usually downstream communities and industries) and service “providers” (upstream communities who are considered forest stewards). PES schemes have limitations, however: for example, they rely on the complex valuation of ecosystem services, often require formal land-tenure arrangements, depend on evidence that services are delivered, and can have implications for socio-economic power dynamics. These limitations may explain the lack of successful PES schemes. Other incentive mechanisms exist. For example, “reciprocal watershed agreements” are simple grassroots versions of conditional transfers that help land managers in upper watershed areas to sustainably manage their forest and water resources in ways that benefit both themselves and downstream water users. Like PES, reciprocal watershed agreements depend on an understanding that hydrological services are being provided, and they rely on recognized conditions of tenure at the local level (i.e. who owns, controls and grants access to watershed forests). In contrast to PES schemes, however, reciprocal watershed agreements offer demand-led rewards rather than monetary incentives, with compensation based on specific needs that diversify income sources. For example, downstream water users could provide upstream landowners with improved livelihood options such as beehives, fruit-tree seedlings and better irrigation equipment (Porras and Asquith, 2018). Reciprocal watershed agreements have been implemented successfully in Bolivia (Plurinational State of), where more than 270 000 water users have signed agreements with 6 871 upstream landowners to conserve 367 148 ha of water-producing forests. In return, the reciprocity-based conservation agreements provide sufficient funding for alternative development projects such as drip irrigation, fruit and honey production and improved cattle management. Fifty-two municipalities in the country have adopted such agreements since 2003 (Natura Foundation, 2019). The success of reciprocal watershed agreements in Bolivia (Plurinational State of) may be due partly to the fact that the agreements have been made in areas with cloud forests: people can see that deforestation reduces dry-season flows and that improved cattle management that restricts livestock movement improves water quality. In such cases, upstream conservation measures can easily be shown to contribute to the protection of watershed services – without the need for detailed and costly hydrological assessments. In addition, scale and local perceptions of forest–water links matter. The watersheds subject to the agreements are small, and there is a limited number of land uses and stakeholders; it is easier, therefore, to see the benefits of improved management, and land managers and water users can easily be identified. Moreover, the mechanism is likely to be more successful in areas where local stakeholders already understand and perceive the links between forest management and maintaining healthy freshwater ecosystems.

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A GLOBAL PICTURE OF FORESTS Despite growing recognition of the for example, the United States Forest AND WATER influence and importance of forests for Service identifies itself as the manager of An estimated 31 percent of the global land water, only 25 percent of forests globally the nation’s largest water resource (United area is forested, of which 65 percent is are managed with soil and water conser- States Forest Service, 2017). Europe falls degraded (FAO, 2010; 2015). The World vation as one of the primary objectives below the global average of managing Resources Institute calculates tree-cover (Figure 1). Moreover, a little less than 10 forests for soil and water conservation trends by major water basin,3 or hydro- percent of forests is managed primarily because most forest land is privately owned shed, as well as water-related hazard risk for soil and water conservation, includ- and is not accounted for in national report- (i.e. erosion, forest fire and baseline water ing around 2 percent managed primarily ing; however, a recent report provided stress4). Before 2000, hydrosheds averaged for clean water and about 1 percent each ample evidence of integrated approaches to 68 percent tree cover; this had reduced to for coastal stabilization and soil erosion forest–water management in Europe (FAO 31 percent by 2000, however, and to 29 control (FAO, 2015). Only 13 countries and UNECE, 2018). In many countries in percent by 2015. This tree-cover loss has report that all their forests are managed the tropics and subtropics, however, there not necessarily been evenly distributed: with consideration given to soil and water approximately 38 percent of the hydro- conservation. 3 FAO divides the world into 230 major basins or sheds had lost more than half their tree More than 70 percent of forests in North watersheds (FAO, 2011a). cover by 2000, rising to 40 percent by 2014 America are managed with consider- 4 Baseline water stress is defined as the ratio of total water withdrawals to total renewable water (WRI, 2017). ations for soil and water conservation; supply in a given area (WRI, 2017). 1 Percentage area of forests for soil and water conservation by country and forest type

0 <10 10−25 25−50 50−75 75−90 >90 no data

1990 2000 2005 2010 2015

500 000

400 000 HECTARES 300 000

200 000

100 000

0 BOREAL TEMPERATE SUBTROPICAL TROPICAL

Source: FAO (2018b).

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is a negative trend in the area of forests as floods, forest fires, landslides and storm Sustainable Development Goals managed for soil and water conservation, surges. Of the hydrosheds that had lost The interconnection between forests and and deforestation is also ongoing. Although at least half their tree cover by 2015, 88 water is explicitly referenced in two SDGs: all forests have impacts on hydrology, the percent had a medium to very high risk of SDG 6 (“Clean water and sanitation”) and loss of tropical and subtropical forests erosion, 68 percent had a medium to very SDG 15 (“Life on land”). In SDG target may disproportionately affect the global high risk of forest fire, and 48 percent had a 6.6, forests are recognized as water-related hydrological cycle (FAO, 2018b). medium to very high risk of baseline water ecosystems; similarly, SDG target 15.1 Decreases in tree cover can lead to stress (WRI, 2017) (Figure 2). refers to forests as freshwater ecosystems. increased soil erosion and degradation Although the indicators for these targets and, in turn, to a reduction in water qual- BUILDING ON INTERNATIONAL do not measure the interlinkages between ity. In some cases, the loss of tree cover MOMENTUM forests and water, methodologies exist is also associated with reduced water The notion of forest management as a for looking at this relationship – which availability, especially when natural for- nature-based solution for water is not new. countries could use to better understand ests are converted to other land uses that The forest–water relationship is a cross- and report on how forests serve as natu- degrade or compact soils, thus reducing cutting issue, and it has gained increased ral infrastructure for water. For example, soil infiltration, water storage capacity and attention in the last two decades (Figure 3). in addition to the indicator used in the groundwater recharge (Bruijnzeel, 2014; The UN Decade on Ecosystem Restoration FAO Global Forest Resources Assessment Ellison et al., 2017; FAO, 2018b). The forest (2021–2030) will undoubtedly raise the (“area of forests managed for soil and water loss and degradation associated with land profile of forest management as a nature- conservation”), Ramsar (2019) specifies conversion and poor land management based solution for water to new heights other forested or tree-covered areas, such practices may also increase the risk to and because of the wide-ranging potential as peatlands, as wetlands. Around 123 damage from water-related hazards, such impacts of restoration on hydrology and million ha of forest – about 2.9 percent of the need to take these into account in plan- the world’s forest area – are classified as 2 ning restoration initiatives. Ramsar sites. Hydroshed risk to erosion and base water stress, by percentage tree cover loss

Erosion risk by % tree cover loss Baseline water stress risk Forest fire risk by by % tree cover loss (2015) % tree cover loss (2015)

35 35 35

30 30 30

Very high Very high Very high High High High Medium 25 Medium 25 Medium 25 Low Low Low Very low Very low Very low

20 20 20

15 15 15

10 10 10

5 5 5

0 0 0 90% 80% 70% 60% 50% 40% 30% 20% 10% 90% 80% 70% 60% 50% 40% 30% 20% 10% 90% 80% 70% 60% 50% 40% 30% 20% 10%

Source: WRI (2017).

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3 Recent global forest policy initiatives that could encourage nature-based solutions for water

Sustainable Development Goals • SDG 6: Clean water and sanitation • SDG 13: Climate action • SDG 14: Life below water • SDG 15: Life on land • Other SDGs also apply, including SDG 1 (No poverty); SDG 2 (Zero hunger); SDG 8 (Decent work and economic growth); and SDG 11 (Sustainable cities and communities)

United Nations Convention to Combat Desertification • Strategic Objective 1: To improve the condition of affected ecosystems, combat desertification/land degradation, promote sustainable land management and contribute to land degradation neutrality • Strategic Objective 2: To improve the living conditions of affected populations • Strategic Objective 3: To mitigate, adapt to and manage the effects of drought in order to enhance the resilience of vulnerable populations and ecosystems • Strategic Objective 4: To generate global environmental benefits through effective implementation of theConvention

Convention on Biological Diversity Aichi Targets • Target 1: People are aware of the values of biodiversity and the steps they can take to conserve and use it sustainably • Target 4: Sustainable production and consumption with impacts of use of natural resources well within safe ecological limits • Target 5: Rate of loss of all natural habitats, including forests, is at least halved and where feasible brought close to zero, and degradation and fragmentation is significantly reduced • Target 7: Areas under agriculture, aquaculture and forestry are managed sustainably, ensuring conservation of biodiversity • Target 11: Terrestrial and inland water, and coastal and marine areas of particular importance for biodiversity and ecosystem services, are conserved • Target 14: Ecosystems that provide essential services, including services related to water, and contribute to health, livelihoods and well-being, are restored and safeguarded • Target 15: Ecosystem resilience and the contribution of biodiversity to carbon stocks has been enhanced through conservation and restoration

Other international processes • United Nations Framework Convention on Climate Change – countries have made commitments under the Paris Agreement through their nationally determined contributions and national adaptation plans • Sendai Framework for Disaster Risk Reduction: Priority 1 – Understanding disaster risk; Priority 2 – Strengthen- ing disaster risk governance to manage disaster risk; Priority 4 – Enhancing disaster preparedness for effective response and to “build back better” in recovery, rehabilitation and reconstruction • Ramsar Convention on Wetlands: Strategic Goal 1 – Addressing the drivers of wetland loss and degradation; Strategic Goal 3 – Wisely using all wetlands • Forest landscape restoration – countries have made commitments on land restoration by 2030, many including water-related objectives

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(Intended) nationally determined To do this, a scientific understanding of the and building social and environmental contributions context is needed, including the well-being resilience (FAO and UNECE, 2018). Forests and water resources feature and needs of communities and ecosystems. A key challenge of management is to prominently in the nationally determined A transformation in approach may be optimize the multiple benefits and mini- contributions of countries to the Paris required for a rapid transition from tradi- mize the trade-offs. Agreement on climate change. Eighty- tional forest management options, such as • Increase connectivity within eight percent of the original “intended” silviculture for wood production or conser- and between landscapes. Hydrol- nationally determined contributions of vation, to regimes in which the provision of ogy connects landscapes, including countries referenced forests as part of land water-related ecosystem services is the pri- upstream and downstream water bod- use, land-use change and forestry, and 77 mary objective. Nature-based solutions do ies and related terrestrial ecosystems; percent referenced water (French Water not necessarily require additional financial atmospheric water teleconnects land- Partnership and Coalition Eau, 2016). resources; rather, they have the potential to scapes at the continental scale. The Forty-nine percent of 168 (intended) enable the more effective use of existing conservation and restoration of upland nationally determined contributions refer financing (WWAP, 2018) by increasing the forests and peatlands, the establishment to the interlinkages between forest and value of multiple forest goods and services, of riparian networks, and the restora- water management, including references including water, and reducing investments tion of meandering water courses and to integrated (water) resource manage- in grey infrastructure. wetlands will help maintain the hydro- ment and the water ecosystem services The following recommendations are logical functionality of landscapes, and provided by forests and mangroves, with made to facilitate the rapid transition restored areas will also function as bio- the majority of these references included towards nature-based solutions for water. diversity corridors for terrestrial and under adaptation measures. Of the coun- • Implement science-based manage- aquatic species. tries indicating their nationally determined ment and guidelines. Forest man- • Greatly intensify collaboration contributions, those in Africa, Asia and agement for water ecosystem services among sectors. The integration Latin America give most recognition to not only needs to take into account of natural and human-made the importance of forest management as a current environmental and socio- infrastructure is needed to address nature-based solution for water (Springgay economic conditions but also future global water, land and urban et al., forthcoming). projections related to land-use planning challenges effectively. This requires Although nationally determined and climate scenarios. The aim of spe- forestry to collaborate with other contributions do not imply resource cies selection, spacing, thinning and sectors, including water, agriculture, commitments until 2020, the strong rotation cycles should be to optimize urban planning, disaster risk man- acknowledgement of forest–water rela- water ecosystem services, biomass and agement and energy. Collaboration tionships within them suggests there carbon storage and manage potential between ministries in governments is significant political will to address trade-offs. Examples exist of landscape poses well-known challenges; at the the issue, offering an opportunity to management (such as ecosystem-based local level, on the other hand, many promote the integration of forests as management) that prioritizes eco­system stakeholders – governments, landown- natural infrastructure in water integrity and functionality, and these ers and businesses – are involved in management. could be more widely employed and multiple sectors as managers of lands integrated. and forests and their associated water GLOBAL CHALLENGES NEED • Bundle benefits in schemes to better resources. Is it possible to engage with CROSS-CUTTING, INTEGRATED compensate landowners and man- other sectors without fighting for juris- SOLUTIONS agers for their water management dictional control? The forest sector Changing the landscape changes the practices. Managing forests for water should consider marketing its skills hydrology. This is true for all scenarios – can produce a wide range of other in forest management and long-term whether tree-cover loss results in land-use goods and services, including carbon planning to other sectors reliant on change, or a degraded landscape is restored sequestration, biodiversity conserva- sustainable forest and tree manage- through reforestation or afforestation. To tion, cultural services (e.g. education ment as a nature-based solution for fully take into account the impacts of and recreation), and wood and non- the immense challenges facing our forest-related landscape change on water wood forest products. The bundling water resources. u in land management decisions, it is neces- of the multiple benefits of forests is sary to consider temporal and spatial scales a cost-effective means for increasing as well as short- and long-term objectives. income opportunities for communities

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Centre for Research on the Epidemiology of FAO. 2018a. Review of the State of the World Disasters (CRED) and United Nations Office Fishery Resources: inland fisheries. FAO for Disaster Risk Reduction (UNISDR). Fisheries and Aquaculture Circular No. C942 References Creed, I.F. & van Noordwijk, M., eds. 2018. Rev.3. Rome. Forest and water on a changing planet: FAO. 2018b. The State of the World’s Forests Abell, R., Asquith, N., Boccaletti, G., Bremer, vulnerability, adaptation and governance 2018: Forest pathways to sustainable L., Chapin, E., Erickson-Quiroz, A. & opportunities. A global assessment report. development. Rome (available at www.fao. Higgins, J., et al. 2017. Beyond the source: IUFRO World Series, Volume 38. Vienna, org/3/I9535EN/i9535en.pdf). the environmental, economic and community International Union of Forest Research FAO. Undated. AQUASTAT [online]. FAO. benefits of source water protection. Organizations (IUFRO). 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Four Cohen-Shacham, E., Walters, G., Janzen, hydrological basins (derived from billion people facing severe water scarcity. C. & Maginnis, S., eds. 2016. Nature- HydroSHEDS). Science Advances, 2(2). based solutions to address global societal FAO. 2011b. Save and grow: a policy maker’s Millennium Ecosystem Assessment. 2005. challenges. Gland, Switzerland, International guide to the sustainable intensification of Global assessment report. Washington, DC, Union for Conservation of Nature. the smallholder crop production. Rome. Island Press. CRED & UNISDR. 2015. The human cost FAO. 2015. Global Forest Resources Nagabhatla, N., Springgay, E. & Dudley, N. of weather-related disasters 1995–2015. Assessment 2015. Rome. 2018. Forests as nature-based solutions for

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ensuring urban water security. Unasylva, UNEP. 2016. A snapshot of the world’s water fs.fed.us/science-technology/water-air-soil 250: 43–52. quality: towards a global assessment. Van der Ent, R.J., Savenije, H.H.G., Schaefli, Natura Foundation. 2019. Watershared Nairobi, United Nations Environment B. & Steele-Dunne, S.C. 2010. Origin and Program [online]. [Cited June 2019]. www. Programme (UNEP). fate of atmospheric moisture over continents. naturabolivia.org/en/watershared-2 UNESCAP/UNISDR. 2012. Reducing Water Resources Research, 49(9). OECD. 2015. OECD Principles on water vulnerability and exposure to disasters. Veolia & IFPRI. 2015. The murky future of governance [online]. Organisation for The Asia-Pacific Disaster Report 2012. global water quality: new global study Economic Co-operation and Development Bangkok, United Nations Economic and projects rapid deterioration in water quality. (OECD). [Cited June 2019]. www.oecd. Social Commission for Asia and the Pacific Washington, DC, International Food Policy org/governance/oecd-principles-on-water- (UNESCAP)/United Nations Office for Research Institute (IFPRI)/Veolia. governance.htm Disaster Risk Reduction (UNISDR). Wada, Y., Flörke, M., Hanasaki, N., Eisner, Oki, T. & Kanae, S. 2006. Global hydrological United Nations. 2018. 2018 Revision of world S., Fischer, G., Tramberend, S., Satoh, Y., cycles and world water resources. Science, urbanization prospects [online]. [Cited Van Vliet, M.T.H., Yillia, P., Ringler, C., 313(5790): 1068–1072. June 2019]. www.un.org/development/ Burek, P. & Wiberg, D. 2016. Modelling Porras, I. &. Asquith, A. 2018. Ecosystems, desa/publications/2018-revision-of-world- global water use for the 21st century: the poverty alleviation and conditional urbanization-prospects.html Water Futures and Solutions (WFaS) transfers. London, International Institute United Nations World Water Assessment initiative and its approaches. Geoscientific for Environment and Development (IIED). Programme (WWAP). 2015. The United Model Development, 9: 175–222. Ramsar Convention Secretariat. 2016. An Nations World Water Development Report World Bank. 2012. Inclusive green growth: introduction to the Ramsar Convention on 2015: Water for a sustainable world. Paris, the pathway to sustainable development. Wetlands. Gland, Switzerland (available United Nations Educational, Scientific and Washington, DC. at www.ramsar.org/sites/default/files/ Cultural Organization (UNESCO). WRI. 2017. Global Forest Water Watch [online]. documents/library/handbook1_5ed_ United Nations World Water Assessment World Resource Institute (WRI). [Cited June introductiontoconvention_e.pdf Programme (WWAP). 2017. The United 2019]. www.globalforestwatch.org. Ramsar Sites Information Service. 2019. Nations World Water Development Report WWF. 2018. Living Planet Report 2018: Ramsar Sites Information Service [online]. 2017: Wastewater: the untapped resource. Aiming higher. M. Grooten & R.E.A. [Cited June 2019]. https://rsis.ramsar.org Paris, United Nations Educational, Scientific Almost, eds. Gland, Switzerland, WWF. u Sonneveld, B.G.J.S., Merbis, M.D., Alfarra, and Cultural Organization (UNESCO). A., Ünver, O. & Arnal, M.A. 2018. Nature- United Nations World Water Assessment based solutions for agricultural water Programme (WWAP). 2018. The United management and food security. FAO Land Nations World Water Development Report and Water Discussion Paper no. 12. Rome, 2018: Nature-based solutions for water. FAO. Licence: CC BY-NC-SA 3.0 IGO. Paris, United Nations Educational, Scientific Springgay, E., Casallas, S., Janzen, S. & and Cultural Organization (UNESCO). Brito, V.V. Forthcoming. The forest–water United States Forest Service. 2017. Water, air, nexus: an international perspective. Forests. and soil [online]. [Cited June 2019]. www.

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Upwind forests: managing moisture recycling for nature-based resilience

D. Ellison, L. Wang-Erlandsson, R. van der Ent and M. van Noordwijk

Trees and forests multiply the fficient and effective forest and however, tends to focus on river flows and oceanic supply of freshwater water-related nature-based solu- to take rainfall for granted as an unruly, through moisture recycling, tions to challenges in human devel- unmanageable input to the system (Ellison, pointing to an urgent need to halt Eopment require a holistic understanding Futter and Bishop, 2012). Thus, the poten- deforestation and offering a way to of the role of forest–water interactions tial impact of increased tree and forest increase the water-related benefits in hydrologic flows and water supply in cover on downwind rainfall and potential of forest restoration. local, regional and continental landscapes. water supply is both underestimated and Forest and water resource management, underappreciated.

Afternoon clouds over the Amazon rainforest

David Ellison is at the Department of Forest Resource Management, Swedish University of Agricultural Sciences, Umeå, Sweden, Adjunct Researcher, Sustainable Land Management Unit, Institute of Geography, University of Bern, Switzerland, and at Ellison Consulting, Baar, Switzerland. Lan Wang-Erlandsson is at the Stockholm Resilience Centre, Stockholm University, Stockholm, Sweden. Ruud van der Ent is at the Department of Water Management, Faculty of Civil Engineering and Geosciences, Delft University of Technology, Delft, the Netherlands, and the Department of Physical Geography, Faculty of Geosciences, Utrecht University, Utrecht, the Netherlands. Meine van Noordwijk is at the World Agroforestry Centre, Bogor, Indonesia, and Plant Production Systems, Wageningen University,

Wageningen, the Netherlands. © NASA IMAGE COURTESY JEFF SCHMALTZ, MODIS RAPID RESPONSE NASA GSFC AT

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On average, about 60 percent of all 10 percent of the Earth’s land surface but al., 2014, 2010; Gebrehiwot et al., 2019). transpiration and other sources of ter- contribute 22 percent of global evapotrans- The long-distance relationships between restrial evaporation (jointly referred to as piration (Wang-Erlandsson et al., 2014), forests, moisture recycling and rainfall evapotranspiration) returns as precipita- an important share of which returns to challenge conventional forest–water tion over land through terrestrial moisture land as rainfall. Moreover, deep-rooted analyses based on catchments as the recycling, and approximately 40 percent trees are able to access soil moisture and principal unit of analysis (Ellison, Futter of all terrestrial rainfall originates from groundwater and thus continue to tran- and Bishop, 2012; Wang-Erlandsson et al., evapotranspiration (van der Ent et al., 2010; spire during dry periods when grasses are 2018). Catchment-centric studies tend to see also Figure 1). From the perspective of dormant, providing crucial moisture for ignore evapotranspiration once it has left a river, evapotranspiration may appear as rainfall when water is most scarce (Staal the confines of the basin in which it was a loss but, for the extended landscape, the et al., 2018; Teuling et al., 2010). produced, despite its key contributions recycling of atmospheric moisture (“rivers Nature-based solutions involving for- elsewhere to downwind rainfall (Ellison, in the sky”) supports downwind rainfall. est and landscape restoration, therefore, Futter and Bishop, 2012) – and the view Forests are disproportionately impor- have the potential to influence rainfall that evapotranspiration represents a loss tant for rainfall generation. On average, and consequently sometimes very dis- rather than a contribution to the hydrologic their water use is 10–30 percent closer tant, downwind rainfall systems reliant cycle has resulted in a pronounced bias to the climatically determined potential on moisture recycling for food produc- both against forests and in favour of the evapotranspiration than that of agricul- tion, water supply and landscape resilience catchment-based water balance (Bennett tural crops or pastures (Creed and van (Bagley et al., 2012; Dirmeyer et al., and Barton, 2018; Dennedy-Frank and Noordwijk, 2018). For example, tropical 2014; Dirmeyer, Brubaker and DelSole, evergreen broadleaf forests occupy about 2009; Ellison et al., 2017; van der Ent et 1 The global hydrologic landscape

ATMOSPHERIC MOISTURE TRANSPORT 45 FO HUMIDITY AND PRECIPITATION BIOPRECIPITATION RECYCLING TRIGGERS DOWNWIND L LOCAL AND GLOBAL AT REGIONAL L SCALE HEATING AND CONTINENTAL AND COOLING SCALE 75 E 120 P

O FOG/CLOUD O INTERCEPTION FLOOD

455 E MODERATION 410 P

DOWNSTREAM INFILTRATION AND GROUNDWATER RECHARGE

5

OCEAN LAND 45 FL

Notes: F represents “net” atmospheric moisture exchange between land (L) and ocean (O). Inflows of atmospheric moisture to land from the ocean are, on average, about 75 000 km3 per year, significantly larger than the “net” inflows of 45 000 km3 suggest (van der Ent et al., 2010). Likewise, the evapotranspiration contribution to rainfall over oceans is approximately 30 000 km3 per year (van der Ent et al., 2010). Sources: Adapted from Ellison et al. (2017), with quantifications of water flow (i.e. ocean evaporation, EO; evapotranspiration, EL; ocean precipitation, PO; land precipitation, PL; net ocean-to-land moisture flow, FO, rainbow arrow; and runoff, FL, black arrow) in 1 000 km3 per year from van der Ent and Tuinenburg (2017).

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Gorelick, 2019; Filoso et al., 2017; Jackson atmospheric long-distance forest–water form of vapour and drops (i.e. evapotrans- et al., 2005; Trabucco et al., 2008). relationships, and discuss some of the key piration and precipitation); and, second, New modelling capacities and increased challenges and opportunities for using for- those that flow horizontally as atmospheric data availability, however, make it pos- ests as nature-based solutions for water. moisture (thus, rivers in the sky) (Figure 1). sible for scientists to better and more easily Our focus is on the role of forests for On average, approximately 75 000 km3 of quantify where and how much forests rainfall and water supply through mois- water per year evapotranspires from land contribute to rainfall. The last decade ture recycling. Thus, we ignore the many into the atmosphere, where it combines has seen a surge, not only in understand- other invaluable benefits of forest–water with evaporation of oceanic origin (Oki ing of the forest–rainfall relationship interactions, such as flood moderation, and Kanae, 2006; Rodell et al., 2015; through moisture recycling, but also in water purification, infiltration, groundwater Trenberth, Fasullo and Mackaro, 2011). the scientific exploration of landscape, recharge and terrestrial surface cooling (see Of the evapotranspiration from land, some forest and water management and gov- Ellison et al., 2017). falls as rain over oceans, but 60 percent – ernance opportunities (Creed and van about 45 000 km3 per year – falls as rainfall Noordwijk, 2018; Ellison et al., 2017; Keys FORESTS SUPPLY AND MULTIPLY over land (Dirmeyer et al., 2014; van der et al., 2017). FRESHWATER RESOURCES Ent et al., 2010). In total, evapotranspira- In this article we review the role of The global distribution of moisture tion contributes approximately 40 percent forests as water recycler and water-resource recycling of the 120 000 km3 of water per year that multiplier, examine the implications of The largest water flows over land are not precipitates over land. those in rivers but rather those that “invisi- Trees, forests and other vegetation Trees contribute to evapotranspiration bly” flow first in the vertical direction in the play pivotal roles in supporting both by accessing deep soil moisture and groundwater, as well as through interception © JOAKIM WANG-ERLANDSSON

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evapotranspiration and precipitation. On Gordon, 2001), as opposed to evaporation under current atmospheric circulation con- a global average, transpiration makes from bare soil or open water evaporation ditions. In large parts of Europe, the eastern up about 60 percent of total evapotrans­ (Miralles et al., 2016; Wang-Erlandsson Russian Federation, East Africa and north- piration, with a large uncertainty range et al., 2014). Climate model simulations ern South America, more than one-third of (Coenders-Gerrits et al., 2014; Schlesinger suggest that a green planet with maximum evapotranspiration is vegetation-regulated and Jasechko, 2014; Wang-Erlandsson et vegetation could supply three times as (i.e. occurs because of the presence of veg- al., 2014; Wei et al., 2017). Vegetation’s much evapotranspiration from land and etation) and falls as precipitation over land direct contribution to total evapotrans- twice as much rainfall as a desert world (Figure 3, p. 21). In parts of Eurasia, piration, however, also includes canopy, with no vegetation (Kleidon, Fraedrich North America, southern South America forest-floor and soil-surface evaporation, as and Heimann, 2000). and large parts of subtropical and dryland well as epiphyte interception. Significantly Tree-, forest- and vegetation-regulated Africa, more than one-third of precipitation more than 90 percent of total terrestrial moisture recycling is unevenly distributed. comes from vapour flows that would not evapotranspiration comes from vegetated Figure 2a shows the rainfall-generation ben- occur without vegetation (Keys, Wang- land (Abbott et al., 2019; Rockström and efits provided by existing vegetation cover Erlandsson and Gordon, 2016).

2 a) Share of evapotranspiration that is vegetation- regulated and falls as precipitation over land (%)

b) Share of precipitation that comes from upwind vegetation-regulated evapotranspiration (%)

Notes: The figure shows the relative importance of current global vegetation for evaporation that returns as precipitation on land (top panel), and precipitation that originates as evapotranspiration on land (bottom). The estimates are based on model coupling between the hydrologic model STEAM and the moisture-tracking model WAM-2layers, simulating a “current land” and a “barren land/sparse vegetation” scenario. “Vegetation- regulated” evapotranspiration and precipitation are defined as the difference in evapotranspiration and precipitation between these two scenarios. The destination of evapotranspiration and origin of precipitation are subsequently determined using WAM-2layers. These model simulations capture the immediate interactions with the atmospheric water cycle but do not consider changes in circulation, soil quality, runoff and water availability. Source: Keys, Wang-Erlandsson and Gordon (2016), used here under a CC BY 4.0 licence.

Unasylva 251, Vol. 70, 2019/1 18 © LAN WANG-ERLANDSSON

Trees contribute to the redistribution of both stream and atmospheric moisture flows Key aspects of forest moisture recy- roughly half the evapotranspiration returns cling: moisture retention and rainfall as rainfall over land (van der Ent et al., Most regions of the world are essentially multiplier 2010). Where rainfall exceeds actual dependent, to varying degrees, on the abil- In general, heavily forested regions amounts of evapotranspiration, rivers are ity of landscapes to recycle moisture to exhibit more intense moisture recycling fed by surplus flows. Thus, where forest downwind locations. Without vegetation- than non-forested regions. During wet loss breaks the moisture recycling chain, regulated precipitation, a significant share periods, transpiration, rainfall and the there are potentially cascading downwind of rainfall across land surfaces would be water intercepted by leaves in a forest are consequences for both rainfall and river lost. Moreover, vegetation regulation can closely related to each other in time and flows (Ellison et al., 2017; Gebrehiwot critically influence the length of grow- space. The average distance that water et al., 2019; Lovejoy and Nobre, 2018; ing seasons and becomes even more particles travel from forested regions Molina et al., 2019; Nobre, 2014; Sheil important in dry periods (Keys, Wang- during the wet season can be as low as and Murdiyarso, 2009; Wang-Erlandsson Erlandsson and Gordon, 2016). Thus, 500–1 000 km, especially in rainforest (van et al., 2018). considerable benefit can be obtained der Ent and Savenije, 2011). Evaporated Further, forests differ crucially from from restoring very large shares of moisture from denser rainforests spends shorter vegetation types in their larger deforested and degraded landscapes (on average) less than five days in the water-storage potential – below the ground, with trees and forests in order to sustain atmosphere (van der Ent and Tuinenburg, on the forest floor and in the canopy. This and intensify the hydrologic cycle and 2017). This illustrates the ability of for- storage allows trees to return significantly thus increase the availability of fresh- ests to create their own rainfall. In large more rainfall to the atmosphere as evapo- water resources on terrestrial surfaces. parts of the Amazon and Congo basins, transpiration over longer periods of time,

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even without rain. Soil-moisture storage, and green water,1 where the total amount from clouds and fog represent additional therefore, enables forests to play an espe- of water available is influenced solely by benefits from adding tree and forest cover cially important role in the water cycle interannual climatic variation in the total (Bright et al., 2017; Bruijnzeel, Mulligan when water is most scarce. Forests develop quantities of precipitation. Based on this and Scatena, 2011; Ellison et al., 2017; deep roots to cope with droughts, in con- newer understanding of the hydrologic Ghazoul and Sheil, 2010; Hesslerová et trast to shorter vegetation types, which cycle, rainfall is an endogenous systemic al., 2013). tend to go dormant (Wang-Erlandsson et element and responds to changing land-use al., 2016). With deeper roots, trees are able conditions within and across landscapes. NATURE-BASED SOLUTIONS AND to both store and access more water in ECOSYSTEM-BASED ADAPTATION the soil, which they use for transpiration Moisture recycling and the role of To facilitate a moisture-recycling- during periods without rain (Teuling et al., catchments based rethinking of trees and forests 2010) as well as to tap into groundwater For the most part, moisture recycling makes as nature-based solutions, we highlight resources (Fan et al., 2017; Sheil, 2014). its principal contributions at distances well key differences in the consideration of This transpired moisture generates dry- beyond the catchment scale. This can pres- green- and blue-water availability; the season rainfall in more-distant regions (van ent a dilemma for local water-resource multiple benefits of forest-supplied mois- der Ent et al., 2014), which can be essen- managers because planting more trees and ture recycling; the precipitationshed and tial for buffering ecosystems, farmlands forests in an individual catchment will evaporationshed as conceptual tools; and and human communities against drought typically have the effect of flushing more challenges for the governance of forest- (Staal et al., 2018). Because dry seasons water resources out of the same catch- moisture recycling across competing and droughts often mean declines in the ment and into the atmosphere (Bennett and interests and scales. supply of ocean evaporation to land, the Barton, 2018; Calder et al., 2007; Dennedy- relative role of forests can be heightened Frank and Gorelick, 2019; Filoso et al., Rethinking total available water: in dry periods (Bagley et al., 2012). The 2017; Jackson et al., 2005). Where the the difference between green ability of forests to retain moisture and locally available water supply is limited, and blue water release it in dry periods can help stabilize reforestation may need to be undertaken From the catchment perspective, it may and extend growing seasons – which may in other upwind locations or atmospheric appear to make sense to start from mea- be especially crucial in places experiencing outflows from the catchment compensated. sured precipitation as the expression a climate-change-induced increase in dry Locally, this can be achieved by reducing of total available water supply (Gleick spells and dry seasons. other catchment-based water uses, such as and Palaniappan, 2010; Hoekstra and The ability of forests to retain and pro- those involving croplands, industries and Mekonnen, 2012; Mekonnen and Hoekstra, vide moisture for multiple cycles of rainfall human populations. Regionally, reforesta- 2016; Schyns et al., 2019; Schyns, Booij recycling means that forests not only “re- tion efforts may need to be coordinated so and Hoekstra, 2017). This would ignore, allocate” a fixed amount of precipitation that increased evapotranspiration-related however, evapotranspiration – the “green” but also both multiply that amount and catchment outflows are compensated by production of atmospheric moisture – by further alter the temporal dynamics of increased precipitation inflows from addi- trees, forests, croplands and other forms precipitation. This perspective contrasts tional upwind reforestation. of vegetation (van Noordwijk and Ellison, sharply with conventional catchment-based Not all catchments are water-challenged, 2019). Through moisture recycling, vegeta- water resource management, which consid- and many can benefit from additional forest tion makes water from upwind oceanic ers the total amount of water available on restoration. Thus, in water-rich and flood- sources available across ever more distant terrestrial surfaces as a fixed quantity in prone catchments, trees and forests can inland locations and regulates the climate a zero-sum allocation game between blue aid the redistribution of water resources by cooling terrestrial surfaces (Bagley et to downwind communities while simul- al., 2012; Ellison et al., 2017; Ellison, 1 The green and blue water paradigm divides taneously facilitating local infiltration, Futter and Bishop, 2012; van der Ent et al., up the catchment water balance into multiple components. Green water represents all water soil storage and groundwater recharge 2010; Keys, Wang-Erlandsson and Gordon, that is evapotranspired back to the atmosphere (Bargués Tobella et al., 2014; Bruijnzeel, 2016; van Noordwijk et al., 2014; Sheil by trees, plants, croplands and open water bodies. 2004; Ilstedt et al., 2016; McDonnell et al., and Murdiyarso, 2009; Wang-Erlandsson Blue water represents the remaining surface and groundwater that is available for human 2018). Moreover, adding more trees and et al., 2018). consumption and industrial use. Grey water, forests can help moderate flooding (van Along upwind coasts, the appropriation generally not discussed here, represents water Noordwijk, Tanika and Lusiana, 2017) and of one unit of freshwater for human or that has been degraded through industrial or human use (Falkenmark and Rockström, 2006; reduce erosion. The cooling of terrestrial industrial consumption is worth many Hoekstra, 2011). surfaces and the absorption of moisture times the same amount in downwind

Unasylva 251, Vol. 70, 2019/1 20 ALEXIS IS BROSS LICENSED UNDER 2.0 CC BY-NC-SA Deforestation-induced reductions in rainfall not only affect ecosystems it might be more useful to consider “poten- “maximum vegetation” scenario (i.e. 100 and agriculture but also the water tially available” water. This can largely percent dense forest cover over land) could supplies of cities, such as the megacity of Tokyo, Japan be considered a function of three factors: be almost twice that of a desert world, or 1) how much of the upwind local catchment about 137 000 km3 of precipitation per water availability. Thus, different ele- water balance can be recycled back into year compared with 71 000 km3 per year ments of the blue, green and grey water the atmosphere for potential downwind in the “no-vegetation” scenario, due to paradigm cannot be treated as removable rainfall; 2) how many times the oceanic increased water recycling and surface or interchangeable modular units that contribution to the terrestrial water budget radiation and despite increased cloud cover. can simply be plugged into or out of a can be recycled in this way; and 3) the Their estimate suggests a doubling of the system at will. The whole is not equal to extent to which increased recycling can evapotranspiration-to-land precipitation the sum of its parts (van Noordwijk and dampen dry spells and shorten the length ratio relative to a desert world and sug- Ellison, 2019). An alternative – but rarely of dry seasons. gests a potential addition of some 17 000 recognized – strategy for managing and Given that 40–50 percent of the world’s km3 in total annual rainfall compared to potentially improving catchment-based forests have already been removed from the current total annual rainfall estimated water availability is therefore to increase terrestrial surfaces (Crowther et al., 2015), in Figure 1.2 In less-extreme scenarios the amount of upwind forest cover in order a crucial question is: How much additional and assuming fixed moisture-recycling to bring more rainfall to downwind basins freshwater could be added to the terrestrial (Creed and van Noordwijk, 2018; Dalton et water budget by progressively restoring 2 Global hydrologic cycle estimates of total annual al., 2016; Ellison, 2018; Keys et al., 2012; previously forested and currently degraded rainfall vary in the range of approximately 99 000–129 000 km3 (Abbott et al., 2019; Weng et al., 2019). landscapes? The extreme-scenario simula- Trenberth et al., 2011). Thus, incorporating this In contrast to the predominant tion by Kleidon, Fraedrich and Heimann uncertainty into the estimate by Kleidon, Frae- catchment-centric approach to measuring (2000), based on one climate model, sug- drich and Heimann (2000) yields an approximate range of +8 000–+37 000 km3 per year. and allocating terrestrial water resources, gested that terrestrial precipitation in a

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ratios, another study suggested that poten- solutions. Payment schemes for ecosys- thereby reducing evapotranspiration and tial vegetation (i.e. the natural potential tem services (Martin-Ortega, Ojea and downwind precipitation. Decreased pre- vegetation state under current climate Roux, 2013) are a possible means by which cipitation, in turn, increases the risk of fire conditions) could lead to an additional 600 such strategies could be implemented on (IUFRO, 2018), which can cause forest loss km3 of terrestrial precipitation per year the ground. To date, however, we are or even self-amplified forest dieback (Staal compared with current land use (Wang- unaware of any ecosystem-based adap- et al., 2015; Zemp et al., 2017). Because Erlandsson et al., 2018). This scenario tation efforts aimed explicitly at putting of the large carbon stores, rich biodiver- includes irrigation, which provides higher moisture‑recycling principles into practice sity and climate regulation provided by evapotranspiration and precipitation than (Creed and van Noordwijk, 2018), despite tropical forests, forest dieback risks trig- “potential vegetation”. the great potential of such forest and land- gering further climate change, cascading In both estimates, the accumulated global scape restoration strategies. On the other regime shifts and teleconnected circulation increase in potential precipitation and hand, models are being developed for when shifts (Boers et al., 2017; Lawrence and water availability masks important spatial and where additional reforestation could be Vandecar, 2015; Rocha et al., 2018). heterogeneity. Large uncertainties around considered to increase moisture recycling Agriculture is not only a major driver the effects of reforestation and afforesta- (Creed and van Noordwijk, 2018; Dalton of forest degradation and deforestation tion on rainfall persist in global models et al., 2016; Ellison, 2018; Gebrehiwot (DeFries et al., 2010) but also a direct and further analysis is needed. et al., 2019; Keys, Wang-Erlandsson and beneficiary of forest-supplied moisture. Gordon, 2018; Wang-Erlandsson et al., Bagley et al. (2012), among others, Nature-based solutions for whom? 2018; Weng et al., 2019). showed that crop yields in major crop- Beneficiaries of forest-supplied rainfall Moisture recycling can have other producing regions could be affected The role of trees and forests in maintaining important impacts on forest resilience. by land-use change through moisture the water cycle is of broad interest and Tropical deforestation in an upwind region recycling at a magnitude similar to points to multiple possibilities for sectoral decreases the total amount of water being climate change. Oliveira et al. (2013) integration in the design of nature-based intercepted and stored in soil surfaces, demonstrated that agricultural expansion

3 Conceptual figure of a precipitationshed, in which the sink region is selected based (for example) on management interest

Source: Keys et al. (2012), used here under a CC-BY-3.0 licence.

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at the expense of Amazon rainforest could rainfall in other locations can be mapped restoration are likely to generate regional- be self-defeating due to the ensuing decline in absolute (e.g. mm per year) or relative scale rainfall benefits but potentially in rainfall. (e.g. percentage of a selected region’s decrease local river flows, local-scale Rainfall not only feeds agriculture evaporation) terms to provide various decision-making may mis-prioritize for- but replenishes all freshwater resources. types of information. Defining absolute est management strategies and policy. Deforestation that reduces rainfall may precipitationshed boundaries can help This suggestion, however, runs counter therefore also have potential consequences in identifying those regions that make to ongoing efforts in many countries to for megacities (i.e. cities with more than the largest moisture contributions to a devolve centralized, institutional deci- 10 million inhabitants), the water supplies selected sink region’s rainfall and thus sion-making frameworks towards local of which are taken from surface water approximately where forest protection autonomy (Creed and van Noordwijk, 2018; (Keys, Wang-Erlandsson and Gordon, or expansion may be most advantageous Colfer and Capistrano, 2005). Striking an 2018; Wang-Erlandsson et al., 2018). For for a specific sink region. A relative appropriate balance between local gov- example, Amazon deforestation was a precipitation­shed shows those regions ernance autonomy and the requirement potential contributing factor in the severe with the highest contributions relative to for larger-scale water management and 2014–2017 droughts in the Brazilian mega- its own local evaporation and thus is useful for identifying and equitably sharing the city of São Paulo (Escobar, 2015; Nazareno for screening regions where restoration cross-scale co-benefits of forest–water and Laurance, 2015). efforts will be most cost-effective. management policies poses a considerable challenge. Precipitationsheds and Context-dependent governance evaporationsheds opportunities CONCLUSION For any area or region of interest – such Moisture-recycling governance in a given Rapidly expanding knowledge on the as a catchment, national park, nation precipitationshed or evaporationshed is role of forest and water interactions in or continent – the sources and sinks of highly context-dependent, varying, for moisture recycling provides important precipitation and evaporation can be deter- example, in the number and size of the new perspectives on how trees and forests mined through moisture tracking. As an countries involved, the heterogeneity can be used to address water scarcity in analogue to the “watershed”, the concept of of land uses within the moisture-recy- effective nature-based solutions. Trees the “precipitationshed” (Figure 3) defines cling domain, the nature and extent of and forests multiply the oceanic sup- regional delineations of upwind locations regional teleconnections, and potentially ply of freshwater resources through based on a threshold of moisture contrib- complex social dynamics (Keys et al., moisture recycling and can assist crop uted and received (Keys et al., 2012). 2017; Keys, Wang-Erlandsson and Gordon, production by improving overall water Studies of precipitationsheds address 2018). For example, the precipitation- availability and thereby prolonging grow- the question: “Where does the evapora- shed of a region in Siberia (the Russian ing seasons. Without forest-supplied tion or evapotranspiration that supplies Federation) is likely to comprise a rela- moisture, terrestrial rainfall would be the precipitation for my selected region tively homogenous area in a single country, considerably lower in amount and extent. occur?” The opposite question can also be whereas a similar-sized region in West Seen as an opportunity, forest-supplied asked: “Where does the evapotranspira- Africa will encompass a wide range of moisture from upwind regions could be tion in my selected region contribute to land-use types in several countries (Keys further enhanced by increasing forest precipitation?” Moisture-tracking studies et al., 2017). These differences in the cover along the moisture-source trajec- can map those areas, sometimes called specifics of particular moisture-recycling tory. In addition to enhancing moisture evaporationsheds (e.g. van der Ent and systems are important considerations in the recycling, increasing tree and fores cover Savenije, 2013). Watershed boundaries design of governance strategies (Keys would have other benefits for water, are determined by landscape topography et al., 2017). such as flood moderation, water purifi- and surface flows; precipitationsheds and Most existing transboundary water cation, increased infiltration, soil water evaporationsheds, on the other hand, are arrangementsdo not extend beyond catch- storage, groundwater recharge and ter- determined by atmospheric moisture flows ments or basins to include source regions restrial surface cooling. that follow wind patterns, vary with season, of atmospheric moisture production (Creed An urgent rethinking is required of and depend on the selection of a region of and van Noordwijk, 2018; Ellison et al., management strategies and the role of interest for which precipitation is tracked 2017; Gebrehiwot et al., 2019; Keys et regional and national governments with back to its evaporative source. al., 2017), despite the obvious inter- a view to creating decision-making Both precipitationsheds and areas pro- est such arrangements should arouse. processes that can adequately consider viding evapotranspiration that returns as Moreover, because forest protection and and better understand the current and

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Dryland forests and agrosilvopastoral systems: water at the core

A.D. del Campo, M. González-Sanchis, U. Ilstedt, A. Bargués-Tobella and S. Ferraz “LEADING HOME” GOATS TASECHO BY IS LICENSED UNDER 2.0 CC BY-NC-ND

A water-centred approach is ryland systems occur on all con- (PET) in dry subhumid and semiarid lands essential for maintaining the tinents and cover about 41 per- is considerably higher than annual pre- resilience of forested drylands in cent of the Earth’s land surface, cipitation, with frequent meteorological the face of climate change. Dwith little variation in this figure in recent droughts. These atmospheric drivers lead decades (Cherlet et al., 2018). Drylands to low soil moisture and this, in turn, means differ in their moisture deficit and can be slow tree growth and low productivity, Antonio del Campo is Associate Professor at the Research Institute for Water and classified in four subtypes according to resulting in a socio-ecological context of Environmental Engineering (Instituto de the United Nations Environment (UNEP) water scarcity. Marked rainfall seasonality, Ingeniería del Agua y Medio Ambiente – aridity index (AI)1 as dry subhumid (0.65– with torrential events followed by long IIAMA), Polytechnic University of Valencia, Spain. 0.5), semiarid (0.5–0.2), arid (0.2–0.05) dry periods, and the combination of high María González-Sanchis is a researcher at or hyperarid (<0.05) (Figure 1).2 Forests intra- and interannual variability, put such IIAMA, Polytechnic University of Valencia, and grasslands are the dominant biomes in regions within the “difficult” hydrology Spain. Ulrik Ilstedt is Assistant Professor at the the dry subhumid and semiarid subtypes, framework, which hampers water secu- Department of Forest Ecology and Management, respectively (more than 60 percent of the rity, sustainable development and poverty Swedish University of Agricultural Sciences. subtype areas). On the other hand, the arid reduction (Grey and Sadoff, 2007). Aida Bargués-Tobella is a postdoctoral and hyperarid subtypes are mostly treeless researcher at the Department of Forest Ecology 1 AI is calculated as precipitation (P) divided and Management, Swedish University of (FAO, 2016) and thus beyond the scope of by PET. Agricultural Sciences, and at the World this article. 2 Additionally, the Convention on Biological Agroforestry Centre. Based on their underlying definition (i.e. Diversity’s delineation includes some areas Silvio Ferraz is Professor at the Department of with presumed dryland features in which Forest Sciences, University of São Paulo, Brazil. by AI), annual potential evapotranspiration P/PET > 0.65 (CBD Secretariat, 2010).

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La Hunde y Palomeras, Spain !

Saponé, Burkina Faso !

Jequitinhonha Valley, Brazil ! Hyperarid Arid Semiarid Dry subhumid Additional areas included in CBD definition

1 World dryland areas Note: Dryland categories are as per definitions by the United Nations Convention to Combat Desertification and the Convention on Biological Diversity (CBD). Black dots show the locations of the case studies. Source: UNEP-WCMC (2007).

Climate change is expected to cause an southern Africa, Australia, the Middle East Climatic constraints increase the role increase in the global area of drylands and Central Asia (Cherlet et al., 2018). The of soil processes and properties in the of 10–23 percent, depending on dryland intensification of precipitation and other regulation and magnitude of water-related subtype, by the end of the twenty-first climatic extremes under warmer conditions issues in drylands, especially those con- century, particularly in areas of North is likely to increase water scarcity and cerned with resource storage (e.g. soil and South America, the Mediterranean, moisture deficits in drylands and beyond. depth, infiltrability, deep-water storage

A combination of land uses (e.g. agriculture, woodlands, pastures and barren land shown here) and management practices (e.g. soil

treatments and the 2009 CAMPO, © A. DEL check dam) interact with climate and soil processes and affect the regulation and magnitude of water- related issues

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and erosion). Thus, land-use and manage- index) are important drivers affecting the CASE STUDIES ment practices, especially nature-based redistribution and subsequent use of water Below, three case studies from drylands solutions, are extremely important for the in the soil profile. on three continents demonstrate how soil–water–productivity complex. water-centred management can improve This article uses case studies in drylands TARGETING WATER IN OBJECTIVES water budgets and local livelihoods, on three continents to show the importance AND MANAGEMENT OPTIONS increase climate-change resilience of a water-centred approach to dryland Drylands provide a wide array of goods and adaptation, and reduce the risk management for increasing resilience and and ecosystem services, but their poten- of disaster. adaption to climate change. tial is often underestimated because they are wrongly perceived to be unproductive Pine reforestation in drylands FOREST ECOSYSTEM PROCESSES (White and Nackoney, 2003). Drylands Monte La Hunde y Palomera (950 metres AND TREE FUNCTIONAL TRAITS support the livelihoods of more than one- above sea level) is a publicly owned dry- Dryland forests and agrosilvopastoral third of the global human population by land forest in eastern Spain (Figure 2). The systems (DFASs) face specific challenges supplying food, forage for livestock and forest covers 4 700 ha, and it includes 887 compared with other vegetation types. Low drinking water. They also provide habitats ha of homogeneous Aleppo pine (Pinus water availability, low growth and unprece­ for species uniquely adapted to variable halepensis) planted between 1945 and dented disturbance regimes (e.g. wildfires and extreme environments, which, in turn, 1970 as part of a national afforestation and pest outbreaks), aggravated by climate constitute sources of genetic material for programme. The Aleppo pine forest has change, make them less resilient and more developing drought-resistant varieties. high tree density (more than 1 500 trees prone to shifts toward less-productive Because of their great extent, drylands can per ha, to increase soil protection) and states (desertification) (Johnstone et al., store large amounts of carbon (Lal, 2004). little silvicultural intervention. The lack of 2016). Anthropogenic pressures (such as The provision of all these goods and intervention is common in many protective those imposed by grazing, browsing, for- ecosystem services is essentially depen- forests in the Mediterranean. est overexploitation and deforestation) add dent on water availability, which is often The Monte La Hunde y Palomera forest complexity and feedbacks. limited, variable and unpredictable but also region has an AI of 0.62, a mean annual Ecohydrology in drylands is mostly cap- fundamental for supporting flora and fauna. temperature of 13.7 ºC, and precipitation of tured by the strong relationship between Vegetation dynamics, soil-water flows and 465 mm (1960–2007). The soils are shal- soil cover and water; that is, forest structure climate are strongly coupled in drylands; low, with high concentrations of carbonate, – both physical (e.g. tree density, canopy the capacity to cope with temporal water a basic pH, and a sandy-silty loam texture. cover and basal area) and biological (spe- shortages is essential for both people’s The lack of forest management, com- cies composition) – has a direct impact livelihoods and the ecosystems them- bined with the climatic characteristics on water-resource availability (Bosch and selves. Thus, water is the key element for of drylands, has produced a dense forest Hewlett, 1982), affecting variables such the socio-ecological resilience of drylands in which growth is stalled; it intercepts as infiltration, evapotranspiration, surface and must constitute a quantitative basis of about 40 percent of gross precipitation and runoff (and erosion) and groundwater any management approach (Falkenmark, severely competes for the other 60 percent recharge. On the one hand, decreasing Wang-Erlandsson and Rockström, 2019). (del Campo et al., 2017, and references canopy cover increases net precipitation, In more humid environments, water yield therein). As a result, the forest is highly which in turn can increase soil moisture has long been quantified as part of eco- susceptible to climatic fluctuations (i.e. and related water flows such as ground- system management (Bosch and Hewlett, rainfall variability), thus increasing its water recharge and water yield, as well as 1982). In dryland ecosystems, water should vulnerability to climate change. Water soil evaporation. On the other, high tree not just be quantified, it should be central infiltration and percolation is essential not cover increases interception and transpi- to land planning and management. More only for the forest itself but also for feed- ration while maximizing soil protection specifically, the emphasis should be on ing two complex aquifer systems, Mancha and enhancing soil infiltration capacity. soil water and aquifer recharge rather Oriental (7 000 km2) and Alpera (400 km2). The explicit consideration of trade-offs than on increasing total runoff or stream- The two aquifers comprise the main water between various hydrological processes flow. Groundwater is the primary water source of 127 000 ha of field crops, but they and vegetation is essential in drylands resource in drylands because surface water have suffered recurrent drought episodes when dealing with resource storage (i.e. resources are generally scarce and highly in the last 20 years. soil and water). Moreover, the water-related unreliable; maximizing its recharge should In this context, the aim of forest manage- traits of tree species (e.g. canopy and root therefore be targeted as a means to increase ment must be to enhance tree growth and architecture, wood density, and leaf area the socio-ecological resilience of drylands. vigour (thus reducing the forest’s climatic

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vulnerability) and soil protection, while also increasing the catchment water bud- get and its contribution to downstream users. Thus, thinning from below at dif- ferent intensities (higher on flat sites, and moderate to light on steeper sites) was performed in a crowded forest, achieving an alternation of firebreak and groundwater recharge areas (tree density <170 trees per ha) together with zones of moderate tree density (450–700 trees per ha), enough to promote tree vigour and infiltration without decreasing soil protection. This manage- ment approach focuses on soils, trees, water and climatic factors and can be considered as ecohydrological-based forest manage- ment. It has proved capable of coping with trade-offs among multiple objectives: canopy interception and stand transpiration

have been reduced; soil water infiltration, © A. CAMARA deep percolation, tree transpiration and Aleppo pine forest, Monte La Hunde y water contributions to the aquifers have climate-change-related disturbances. Palomera forest, eastern Spain all increased; and fuel models have been Ecohydrological forest management also sense of insecurity, which is especially altered. The management changes have has social and economic benefits through- important in the urban–forest interface, produced a forest with less climatic vul- out the catchment. For example, increasing and potentially avoids the costs of dam- nerability and lower fire risk (del Campo the water budget increases the capability age caused by wildfire and the expense of et al., 2017, and references therein) and, of users to cope with drought. Reducing forest restoration. Such benefits arise when which, therefore, is more capable of facing the fire hazard both decreases the public water is put at the core of the management approach. 2 Water contribution (mm/yr) Climate dependence (%) Results of ecosystem 500 30 Agroforestry parklands: management, 25 coping with multiple objectives Monte La Hunde y 400 Palomera 20 but only “one water” 300 15 Saponé is a rural municipality in central 200 Burkina Faso in West Africa. The domi- 10 nant soils are ferric lixisols, with low 100 5 nutrient content and sandy-clay and sandy- 0 0 U M U M loam textures. Mean annual precipitation at Ouagadougou (30 km north of Saponé) Fire risk (%) Economic revenues (€/ha) was 790 mm in 1952–2014 (in the range of 100 Low 1000 570–1 189 mm). Most rainfall occurs in a

80 800 single rainy season, which runs from April to October. Mean annual potential evapo- 60 600 transpiration and mean AI (1974–2003) are 40 400 1 900 mm and 0.38, respectively. 20 200 The landscape is characterized by open

0 High 0 tree cover (30 trees per ha) dominated by U M U M Vitellaria paradoxa (shea), with annual Notes: Forest water contribution (mm/yr); climate dependence (growth dependence on previous monthly precipitation in %); fire risk (percentage of days/year with very crops such as pearl millet, sorghum, high [red], high [orange] and low [green] fire risk); economic revenues (euros per ha), (see del Campo et al., 2017 for specific references). groundnut and cowpea grown under and U = unmanaged, M = managed. among the scattered trees. These cultivated

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more nuanced story. Soil water drainage collected at a depth of 1.5 m was high- est in the area below the edge of the tree canopy and decreased both towards the tree stem and towards the centre of adja- cent open areas among trees (Ilstedt et al., 2016). Thus, little water was available for groundwater recharge both close to tree stems and in the open areas far away from trees. Interception and transpiration losses are higher in the area around tree stems, which explains the reduced deep drainage in this area. The decrease in water drainage observed with increasing distance from the canopy edges of trees towards open areas, on the other hand, can be attributed to the observed concurrent decrease in infiltration capacity and preferential flow (Bargués-Tobella et al., 2014). Thus, trees

© A. CAMARA should not be seen only as water consumers Harvesting aleppo pine, Monte La Hunde y but also as key ecosystem engineers that Palomera forest, eastern Spain result of land use, land-cover conversions enable soil and groundwater recharge. open woodlands are referred to as agro- and human pressure in general; thus, man- In Saponé, groundwater recharge is forestry parklands, and they constitute agement approaches designed to improve maximized at an intermediate canopy the predominant farming system in the local livelihoods should aim to increase cover (Ilstedt et al., 2016). At tree cover Sudano-Sahelian region of West Africa, soil and groundwater recharge. below the optimum, more trees result covering large areas (Boffa, 1999). Trees Trees consume more water than shorter in increased groundwater recharge are actively conserved and promoted on vegetation types such as crops and grasses because the improvement in soil hydrau- farms because of the benefits they provide (Zhang, Dawes and Walker, 2001). Based lic properties conferred by these trees to local communities – including the provi- on this understanding, increasing tree outweighs additional evapotranspiration sion of fruits, nuts, shading, medicines, and cover is often discouraged in drylands losses. The opposite is the case, how- fodder for livestock. because it might jeopardize precious ever, at tree-cover percentages above the Rainfall is highly variable in Saponé. water resources (Jackson et al., 2005). optimum (Figure 3). The relatively short rainy season is char- But results from studies conducted in the Although more research is needed, from acterized by a few intense events unevenly agroforestry parklands of Saponé reveal a a management perspective it is vital to distributed over time, and there is large spatial and interannual rainfall variabil- ity. The soils have low structural stability and are highly vulnerable to physical degradation, such as decreases in soil infil- tration capacity, resulting in limited soil and groundwater recharge opportunities and a higher prevalence of infiltration-excess overland flow. This, in turn, increases the risk of agricultural drought, erosion and flooding, placing considerable constraints on water supply and food production, par-

ticularly given the dominance of rainfed © A. CAMARA crops. Physical degradation is typically a Agroforestry parklands, Saponé, Burkina Faso

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Drainage at 1.5 m depth Tree transpiration Groundwater recharge 90 140 60 80 120 50 70 100 60 40 50 80 30 40 60 mm/year mm/year 30 mm/year 20 40 20 10 10 20 0 0 0 1 10 30 1 10 30 1 10 30 Tree density (trees/ha) Tree density (trees/ha) Tree density (trees/ha)

3 Results of ecosystem management, of rivers draining to the north, northeast, reduces stream flows. In this case, forest Saponé; three tree densities southeast and south of the country. The management should be adjusted to water promote practices that maximize the natural vegetation in the biome has low availability, such as by reducing the area positive impacts of trees on soil hydraulic biomass density and low interception. This, of plantations, increasing rotation lengths properties and minimize tree water use and added to the well-drained soils, means (because water use declines with tree age; interception. Thus, tree species selection, there is a hydric excess responsible for Perry and Jones, 2017), mixing stand ages tree pruning and livestock control offer recharging aquifers and maintaining (to create a mosaic), and reducing manage- opportunities to increase groundwater stream flows (Honda and Durigan, 2017). ment intensity. recharge (Ilstedt et al., 2016). Degradation due to land-use change Another aspect under discussion regard- (mostly to agriculture) is altering this ing the Cerrado biome, mostly in protected Cerrado: the hydrological dynamic, however, leading to contaminated areas and remaining fragments, is the consequences of vegetation streams and reducing water availability. reduction of fire – considered a natural biomass increment The area of short-rotation forest plan- element of Cerrado ecology (Durigan The Cerrado is the second-largest biome in tations has increased in the region, with and Ratter, 2016) – brought about by a Brazil, occupying 204 million ha (24 per- Eucalyptus grandis the most important policy of fire suppression (Durigan and cent of the country’s total land area); it species. The biomass of these forests Ratter, 2016). Fire reduction is leading to is subject to considerable land-use pres- increases rapidly, with the trees explor- an increase in vegetation biomass, which sure (Sano et al., 2019). Vegetation types ing water resources using their deep root in turn results in higher interception and vary along a regional climatic gradient systems and presenting high evapotrans- modified evapotranspiration dynamics depending on local soil and geographical piration, potentially altering the soil water (Passos et al., 2018), causing changes in characteristics and include dry forests, balance. Lima et al. (1990) compared the the hydrological regime and in plant com- scrub woodland, open scrub (sensu stricto soil water balance in Cerrado vegetation munities. Oliveira et al. (2017) monitored Cerrado) and grasslands. Annual precipita- with Pinus and Eucalyptus plantations in piezometric wells in various Cerrado tion is in the range of 1 200–1 800 mm, northeastern Minas Gerais (Jequitinhonha vegetation types over a two-year period presenting high seasonality (with a six- Valley, annual precipitation = 1 121 mm) and showed that the increase in vegetation month dry season) and the AI is slightly and showed that the conversion of natural density reduced watertable recharge from lower than 1. The predominant soils are Cerrado vegetation (36 m3 per ha) to Pinus 363 mm per year (grasslands) to 315 mm deep, highly weathered and acidic, and they caribaea (210 m3 per ha) and Eucalyptus per year (Cerrado). Differences in evapo- have low nutrient concentrations. Because grandis (366 m3 per ha) increased intercep- transpiration rates and soil water content nutrient deficiency can be corrected, and tion losses by 74 mm per year for Pinus and were also observed among vegetation types other soil characteristics are highly favour- 134 mm per year for Eucalyptus (Figure 4). (Miranda et al., 2003). able, some lands in the Cerrado have been The soil water balance decreased from Land-use change in the Cerrado, and in converted to agriculture; production is high 556 mm per year in natural Cerrado veg- other drylands worldwide, requires taking when fertilizers are used. The Cerrado, etation to 450 mm in Pinus and 326 mm into account the hydrological constraints therefore, has become one of the world’s in Eucalyptus. The reduction in water (made clear by the characteristics of the most threatened biodiversity hotspots availability by plantations increases the natural vegetation) to maintain hydro- (Klink and Machado, 2005). effects of natural seasonality (i.e. lower logical processes and the provision of The Cerrado concentrates the headwaters availability during dry seasons) and ecosystem services.

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Water contribution (mm/yr) ET (% of Gr) Interception (% of Gr)

90 14 600 80 12 500 70 10 60 400 50 8 300 40 6 30 200 4 20 100 2 10

0 0 0 P E C P E C P E C

4 Comparison of plantations and natural Cerrado vegetation, Jequitinhonha Valley, Brazil Note: Water contribution (mm/yr); evapotranspiration (% of gross precipitation – Gr); interception (% of Gr). C = Cerrado, E = Eucalyptus, P = Pinus.

CHALLENGES IN THE can contribute to several Sustainable in dryland forests and agrosilvopastoral GOVERNANCE AND MANAGEMENT Development Goals (SDGs), including systems are not clearly marketable, discour- OF DRYLAND FORESTS AND SDG 2 (Zero hunger), SDG 6 (Clean aging potential investment in management. AGROSILVOPASTORAL SYSTEMS water and sanitation) and SDG 15 (Life on Decision-support systems capable of Water plays a fundamental role in socio- land). But it is a highly complex challenge, handling complexity and multiple inter- ecological resilience (Falkenmark, with economic, social, environmental actions, and which might encompass Wang-Erlandsson and Rockström, 2019), and climatic dimensions. The need for economic valuation (Tecle, Shrestha particularly in drylands. Forward-looking multiple goods and services increases and Duckstein, 1998), present a governance and management policies in the complexity of the challenge because potential means for negotiating the com- dryland forests and agrosilvopastoral sys- their quantity, typology and valuation plexity of water-oriented land management tems, therefore, need to consider water (in economic terms) vary with ecosys- in drylands. as a crucial supporting element for the tem type (La Notte et al., 2015) and production of goods and services, at least hamper the potential for a generalized CONCLUSION at the same level as biomass and carbon. approach applicable to all dryland for- The water-oriented management of dryland Water-oriented land management ests and agrosilvopastoral systems. forests and agrosilvopastoral systems may Also, many of the products produced increase water availability and therefore The Cerrado, Brazil socio-ecological resilience. As the case studies presented above show, strate- gies such as canopy opening, pruning and species selection can be effective in combating water scarcity (by increas- ing soil and groundwater recharge) while also increasing climate-change resilience and adaptation. The optimum management intensities and strategies are likely to vary with ecosystem character- istics, even within the same catchment or region. The need to provide multiple goods and eco- system services increases the management challenge but also the potential benefits and therefore management possibilities. The complexity of multi-objective management approaches, and the eco-

© IIAMA logical variability of dryland forests

Unasylva 251, Vol. 70, 2019/1 34 CERRADO (CAVERNA AROE JARI) BY STINKENROBOTER IS LICENSED UNDER CC BY-NC CC 2.0 UNDER LICENSED IS BY STINKENROBOTER JARI) (CAVERNA AROE CERRADO

A patch of Cerrado surrounded by farm fields on the access road to Caverna Aroe Jari, on preferential flow and soil infiltrability Bautista, I., Ruiz, G. & Francés, F. 2017. Mato Grosso, Brazil in an agroforestry parkland in semiarid Ecohydrological-based forest management Burkina Faso. Water Resources Research, in semi-arid climate. In: J. Křeček, M. and agrosilvopastoral systems, means 50(4): 3342–3354. Haigh, T. Hofer, E. Kubin & C. Promper, eds. that more effort is needed to quantify Boffa, J.M. 1999. Agroforestry parklands in Ecosystem services of headwater and value the goods and ecosystem sub-Saharan Africa. FAO Conservation catchments, Chapter 6. Springer International services of dryland forests and agrosilvo- Guide 34. Rome, FAO. Publishing and Capital Publishing Co. pastoral systems and to incorporate this Bosch, J.M. & Hewlett, J.D. 1982. A review Durigan, G. & Ratter, J.A. 2016. The information in management. of catchment experiments to determine need for a consistent fire policy for the effect of vegetation changes on water Cerrado conservation. Journal of Applied ACKNOWLEDGEMENT yield and evapotranspiration. Journal of Ecology, 53(1): 11–15. The authors thank CEHYRFO-MED Hydrology, 55(1–4): 3–23. Falkenmark, M., Wang-Erlandsson, L. & (CGL2017-86839-C3-2-R), LIFE17 CCA/ CBD Secretariat. 2010. Decision adopted Rockström, J. 2019. Understanding of water ES/000063 RESILIENTFORESTS, by the Conference of the Parties to the resilience in the Anthropocene. Journal of Swedish Research Council Formas (2017- Convention on Biological Diversity [CBD] Hydrology, X, 2: 100009. 00430), and Swedish Research Council VR at its tenth meeting: X/35 Biodiversity of FAO. 2016. Trees, forests and land use in grant 2017-05566. u dry and sub-humid lands. Conference of drylands. The first global assessment. the Parties to the Convention on Biological Preliminary findings.Rome . Diversity, Tenth meeting. Nagoya, Japan, Grey, D. & Sadoff, C.W. 2007. Sink or swim? 18–29 October. Water security for growth and development. Cherlet, M., Hutchinson, C., Reynolds, J., Water Policy, 9: 545–571. Hill, J., Sommer, S. & von Maltitz, G., Honda, E.A. & Durigan, G. 2017. A References eds. 2018. World atlas of desertification. restauração de ecossistemas e a produção Luxembourg, Publication Office of the de água. Hoehnea, 44(3): 315–27. Bargués-Tobella, A., Reese, H., Almaw, European Union. Ilstedt, U., Bargués-Tobella, A., Bazié, A., Bayala, J., Malmer, A., Laudon, H. del Campo, A.D., González-Sanchis, M., H.R., Bayala, J., Verbeeten, E., Nyberg, & Ilstedt, U. 2014. The effect of trees Lidón, A., García Prats, A., Lull, C., G., et al. 2016. Intermediate tree cover can

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Gaps in science, policy and practice in the forest–water nexus

M. Gustafsson, I. Creed, J. Dalton, T. Gartner, N. Matthews, J. Reed, L. Samuelson, E. Springgay and A. Tengberg

More knowledge is needed urgently on how to implement effective management regimes for the forest–water nexus.

Malin Gustafsson is P rogram me Officer at the Swedish Water House, Stockholm International Water Institute (SIWI), Stockholm, Sweden. Irena Creed is Professor at the School of Environment and Sustainability, University of Saskatchewan, Saskatoon, Canada. James Dalton is Director of the Global Water Programme, International Union for Conservation of Nature (IUCN), Gland, Switzerland. Todd Gartner is Director of Cities4Forests and the Natural Infrastructure Initiative at the World Resources Institute, Washington, DC, United States of America. Nathanial Matthews is Program Director at the Global Resilience Partnership hosted at the Stockholm Resilience Centre, Stockholm University, Stockholm, Sweden. James Reed is Researcher in the Sustainable Landscapes and Food Systems team at the Center for International Forestry Research, Bogor, Indonesia, and at the University of Cambridge Conservation Research Institute, Cambridge, United Kingdom of Great Britain and Northern Ireland. Lotta Samuelson is Programme Manager at the Swedish Water House, SIWI, Stockholm, Sweden. Elaine Springgay is Forestry Officer at the FAO Forestry Department, Rome, Italy. Anna Tengberg is Program Manager at the Swedish Water House, SIWI, Stockholm, Sweden, and Adjunct Professor at Lund "TREE SCIENCE-9438" BY SOME.DUDE IS LICENSED UNDER CC BY-NC-SA CC 2.0 UNDER LICENSED IS BY SOME.DUDE SCIENCE-9438" "TREE University Centre for Sustainability Studies, Lund University, Lund, Sweden.

The crucial role of trees and forests in hydrologic cycles requires more research

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rees and forests play important INCREASING ATTENTION ON sectors – including those between forests roles in hydrologic cycles, such INTERLINKAGES and water – can be realized (Seddon et as by altering the release of water The need for greater integration among al., 2019). Tinto the atmosphere, influencing soil mois- sectors and scales in natural resource gov- The productivity of multifunctional land- ture and improving soil infiltration and ernance is now widely recognized (e.g. scapes is contingent on the management of groundwater recharge (Springgay et al., Liu et al., 2018), such as by incorporating interlinked forest and water processes and 2018). Forest-related changes in land use stakeholder-driven, bottom-up approaches resources (Ilstedt et al., 2007), which, in such as deforestation, reforestation and into natural resource management strat- turn, requires adequate knowledge of such afforestation can affect both nearby and egies (Creed and van Noordwijk, 2018; linkages. But persistent knowledge gaps distant water supplies (Jones et al., 2019): Tengberg and Valencia, 2018). Landscape on forest–water interactions require atten- for example, a decrease in evapotranspira- approaches are being discussed and, in tion and action if system-based approaches tion following deforestation in one area some cases, adopted in both tropical and such as forest and landscape restoration may reduce rainfall in downwind areas temperate regions in an attempt to rec- (Laestadius et al., 2015; Carmenta and (Ellison et al., 2017). Climate change and oncile often conflicting environmental Vira, 2018) and landscape approaches an increase in extreme weather events are and developmental challenges at broader that holistically consider the importance disturbing water cycles and threatening spatial scales (Estrada-Carmona et al., of healthy forests for sustainable water the stability of water flows (IPCC, 2019). 2014; García-Martín et al., 2016; Reed supplies, and vice versa, are to be applied. Meanwhile, water supplies are affected by et al., 2016). Managing the forest–water nexus is an increase in human water consumption to Forests and water – both of which are integral to achieving many of the SDGs meet domestic, agricultural and industrial integral landscape components – are also and could be better acknowledged in the needs (Rockström et al., 2009). Increasing receiving increased attention in policy implementation of (intended) nation- demand for water is reducing freshwater and practice. The European Union Water ally determined contributions under the flows and groundwater levels, often with Framework Directive, adopted in 2000, has Paris Agreement on climate change. The negative effects on biodiversity, ecosystems been a strong driver of bottom-up public SDGs provide a useful framework for and ecosystem services (Power, 2010). and private partnerships to secure water bringing this nexus to the attention of Water, forests and climate, therefore, are quality and flows. Globally, the Convention policy- and decision-makers. We suggest intrinsically interlinked at multiple levels on Wetlands of International Importance, that, to effectively implement large-scale in what has been termed the forest–water especially as Waterfowl Habitat (generally landscape approaches, adequate attention nexus, but the underlying systems and feed- known as the Ramsar Convention) has must be given to the multifunctionality back loops in forest hydrologic processes raised awareness of the need to conserve of landscapes, including the interactions are poorly understood – and also poorly and sustainably use wetlands, forests and and interdependencies of actions across represented in policy- and decision-making water resources (Tengberg et al., 2018). typically conflicting sectors and their (Creed and van Noordwijk, 2018). At the The SDGs address water in SDG 6 (Clean importance for livelihoods, climate and national level, pervasive policy challenges water and sanitation) and forests in SDG 15 economic resilience. are often confounded by a lack of collabo- (Life on land), although it has been argued ration among key sectors, such as forestry, that all the SDGs are relevant to forest FOREST–WATER INTERLINKAGES: water, energy and agriculture. Complex and water management and use (Creed AREAS OF AGREEMENT multisectoral issues such as forest–water and van Noordwijk, 2018). An increasing AND DISAGREEMENT, AND relations, therefore, tend to be overlooked focus on forests is evident in other recent KNOWLEDGE GAPS and inadequately incorporated into sectoral international conventions and campaigns, Forests and water are linked through their policies. such as the Bonn Challenge, which aims multiple functions, such as the regulation In this article, we draw on our collec- to restore 350 million ha by 2030, the of basin flows, the reduction of floods and tive experience and the recent literature to New York Declaration on Forests, which droughts, and the impacts of forests on highlight knowledge gaps in the integration has the goal of ending deforestation by water yield and quality. There is limited of the forest–water nexus in science, policy 2030, and the Trillion Trees Partnership, knowledge, however, on the factors that and practice, including the climate-change which aims to protect and restore 1 trillion regulate these multiple functions, their discourse and the Sustainable Development trees by 2050. Although the momentum interactions, and ultimately their effects Goals (SDGs). for and pledges towards these endeavours on those relying on them for water and have been significant, challenges remain other ecosystem services. The complexity in translating them into action, and it is of highly contextualized forest–water rela- still unclear whether synergies across tionships requires management decisions

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based on science and an understanding of assessments and the design of supportive as web-based multistakeholder meetings cross-scalar local–national–global con- policies, to dialogue and communication and information sharing via social media ditions (Eriksson et al., 2018). Figure 1 (Table 2). Challenges remain, however, in and public fora. Maps explaining water and Table 1 identify topics where there is overcoming siloed or sectoral approaches yields by ecosystem type, forest cover both agreement and disagreement among to enable the implementation of integrated and other parameters would be useful experts, suggesting a need for further forest and water management. There is in understanding and explaining forest investigation and discussion. For example, often poor communication and a lack of hydrology as part of water management, there is consensus that the hydrologic trust among stakeholders, as well as a lack together with decision-support tools link- processes that are influenced by forests of economic incentives for the sustainable ing science, policy and practice. can influence the water cycle, but there is management of the forest–water nexus. disagreement on the impacts of these inter- Therefore, we encourage new ways of FOREST, WATER, CLIMATE, AND A actions. Ongoing research spans a wide communicating the results of scientific LANDSCAPE PERSPECTIVE range of topics, from technical aspects research using a common terminology and Climate change has many fundamental related to (for example) water budgets, to modern communication approaches, such and increasing impacts on the global water

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1 Areas for further discussion within the forest–water nexus

RELATIONSHIPS BETWEEN FORESTS, PRECIPITATION WATER VAPOUR TRANSPORT AND FLOOD CONTROL

EXTENTEXTENT OFOF THETHE EFFECTSEFFECTS OROR IMPLICATIONSIMPLICATIONS OFOF FORESTFOREST OPTIMAL LOCATION FOR EVAPOTRANSPIRATIONEVAPOTRANSPIRATION ANDAND AND SPACING OF TREES PRECIPITATIONPRECIPITATION RECYCLINGRECYCLING IN THE LANDSCAPE PRECIPITATION

TYPES OF TREES/FORESTS THAT IMPACTS OF MOST EFFICIENTLY REFORESTATION SUPPORT WATER EVAPORATION ON WATER YIELD SUPPLY/ SECURITY OR EVAPOTRANSPIRATION PARAMETERS RELATED TO DEPLETE WATER YIELD A FOREST'S POTENTIAL TO MITIGATE FLOODS

STREAM FLOW

SURFACE RUNOFF INFILTRATION

GROUNDWATER FLOW

BENEFITS/TRADE-OFFS OF FOREST– WATER RESILIENT AND PRODUCTIVE INTERACTIONS ON ECOSYSTEM SERVICES, LANDSCAPES THAT MAXIMIZE THE SUCH AS CARBON SEQUESTRATION AND THE POSITIVE AND NEGATIVE BENEFITS OF ECOSYSTEM SERVICES STORAGE, BIODIVERSITY CONSERVATION, IMPACTS OF FORESTS ON FROM THE FOREST–WATER NEXUS NUTRIENT CYCLING, SEDIMENTS, DOWNSTREAM WATERFLOW FOR ENVIRONMENTAL AND AND SOIL-WATER RETENTION AND GROUNDWATER LIVELIHOOD SECURITY

Note: This conceptual overview and summary of issues in need of further discussion within the forest–water nexus arose from discussions at the first Forest Water Champions workshop in Stockholm, August 2017. cycle and regional weather patterns (Hegerl on climate change (Seddon, 2018), and management of the forest–water nexus. et al., 2015), yet water is rarely visible in ecosystems are increasingly managed for To ensure resilient and productive multi- negotiations within the United Nations water security. But lessons arising from functional landscapes, there is a need to: Framework Convention on Climate Change NBS approaches, such as projects on • improve understanding of hydrologic (UNFCCC). Opportunities have been ecosystem-based adaptation, have been processes at a landscape scale; missed in managing the forest–water nexus inconclusive to date due to monitoring • support the development of new for climate-change adaptation and mitiga- difficulties and a lack of interventions at integrated knowledge that can tion, for example by including nature-based a meaningful scale beyond community underpin evidence-based decision- solutions (NBSs) (Tengberg et al., 2018). projects (Reid et al., 2019). making related to landscapes, forests At the national level, developing coun- The understanding and consideration and water; tries have taken the lead in incorporating of water and hydrologic processes can be • strengthen multilevel governance NBSs in their nationally determined con- used as a key entry point in promoting arrangements that enable genuine tributions (NDCs) to the Paris Agreement landscape restoration and the sustainable stakeholder participation;

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TABLE 1. Areas of agreement, and areas for further discussion, identified at the first Forest Water Champions workshop in Stockholm, August 2017

Theme Areas of agreement Areas for further discussion

Water quantity Trees and forests influence the hydrologic cycle by regulating and affecting basin • Positive and negative impacts of forests on flows through interception, uptake, evapotranspiration, reducing runoff and downstream waterflow and groundwater levels improving soil infiltration and groundwater recharge

The effect of forests on water yield (positive or negative) is dependent on • Types of trees/forests that most efficiently support location, forest type and age, and scale (physical and temporal) water supply/security • Types of trees/forests that deplete water yield • Optimal locations for trees in landscapes Fire is a normal and healthy aspect of many forests, correlating with precipitation regimes and influencing hydrology

Forests can reduce the risk of flooding, but the parameters for reduced flood • Parameters related to the potential of forests to risk are complex, influenced by many factors, and not well known mitigate floods

Evapotranspiration from forests can have a positive effect on downwind • Extent of the effect and implications of forests, precipitation evapotranspiration and precipitation recycling

There is a need to define the parameters of forest–water relationships • Relationships between forests, precipitation and flood control • Impacts of reforestation on water yield • Benefits and impacts of forests at different scales Water quality Forests generally improve water quality through their root systems and stable soil profiles, which can act as natural filters, reducing soil erosion and sedimentation

Forests are crucial for aquatic ecosystems • Impacts of riparian zones and floodplains on fishing communities Policy and The SDGs provide an opportunity to: practice • bring related scientific knowledge to the attention of policy- and decision-makers • highlight areas where the science is not sufficiently comprehensive or is overly simplistic • highlight the need for integrated approaches across sectors and disciplines

• Forests are adapted to environmental conditions – including water • Benefits and trade-offs related to forests and water • Forest–water relationships are scale- and context-dependent interactions – such as carbon storage, climate- change mitigation and adaptation, and extreme • The impacts of forest and land management activities on water and water users depend on local conditions, forest ecology, management regime, scale, events etc. • Development and communication of research, methods and decision-making tools

The following are needed to improve the management of the forest–water • How to achieve these and by whom interface: • a combination of technical and policy measures, summarized in a theory of change • a scientific conceptual framework with the main linkages and interactions between forests and water • the integration into existing tools to manage for uncertainty/risk in sustainable forest management, sustainable land management and integrated water resource management • communication across disciplines and sectors to enable consensus Socio-economics Forest and water resources are part of deeply intertwined socio-ecological • How to best approach and manage a mosaic of systems. Thus, the socio-economic dimensions and implications for governance land uses and other interventions, including natural policies need to be better addressed, with specific attention to climate change, ecosystems and managed systems, to maximize reduced forest functions and increased demand for water for human well-being overall benefits, keeping in mind the equitable distribution of benefits

Ecosystem services from the forest–water nexus need to be better documented, • Whether water accounting needs to re-prioritize accredited and used to develop funding schemes for overall landscape ecosystems and look at a water “net balance”. This development can contribute to a cost–benefit analysis of forests as natural capital in place of or to complement grey infrastructure

Note: The first Forest Water Champions workshop was organized by FAO, IUCN and SIWI. Source: Adapted from Springgay et al. (2018).

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TABLE 2. Summary of group discussions at a parallel session during the IUFRO Joint Conference on Forests and Water held in Valdivia, Chile, in November 2018

Ongoing relevant Vulnerability assessments related to forest-watershed management that integrate science, policy and stakeholder engagement research Research on payments for ecosystem services and how to design supportive policies using social network analysis Support for communication, the compilation of indicators and stakeholder initiatives Water budgets in forestry and agriculture to increase irrigation efficiency Soil management using native forests and subsidies for some activities Development of strategies to work with local communities and facilitate discussions between companies and communities Remaining There is a siloed approach to water – people need to be brought together, but this requires resources, engagement and challenges leadership as well as a platform Building trust among different stakeholders is key. There is, for example, a lack of transparency in companies and a reluctance to share data and information. Landowners do not trust scientists, whom they believe are on the “government’s side”. Non- governmental organizations have an important role to play in building trust between practitioners, policymakers and scientists Scientists, policymakers and practitioners speak different “languages”. Scientists and researchers always sound unsure. Why do they keep saying, “We know this but we don’t know that”? It is important that there is a common objective; this should be clear from the start but is often missing. What are we trying to achieve, and what problems are we trying to solve? Economic incentives for the sustainable management of the forest–water nexus are lacking Communication New ways of communicating results must be developed. For example, cartoons could be used to increase understanding of needs the forest–water nexus by using more pictures and less text. Webinars to raise awareness could be organized There is a need for a common terminology; this could be included in the common objective It is important to communicate the benefits of addressing the forest–water nexus. Why is it needed, and what will we gain? Decision-support tools could be developed jointly by scientists, practitioners and policymakers

Note: The parallel session was co-organized by FAO, SIWI and the Swedish Forest Agency.

• identify and apply best management applied – to performance, equity and to restore degraded forests and landscapes practices and innovative tools for the power dynamics (Kusters et al., 2018; at scale seem remote. Water stress in many sustainable management of forests and Morrison et al., 2019). The establishment countries has been linked to land degra- water in landscapes; and or refinement of existing multistakeholder dation resulting from forest conversion • ensure adequate long-term financing fora can serve to better communicate the (Curtis et al., 2018; IPCC, 2019), and the for landscape approaches that sustain co-benefits of sustainably managing the growing competition for land between, ecosystem services and support liveli- forest–water nexus for climate, landscapes for example, agriculture, industries and hoods (Tengberg et al., 2018). and people; increase awareness of these intensive forestry adds to the challenge. Achieving successful and inclusive benefits among policymakers, civil society Below, we outline the key implications and multistakeholder dialogue will inevita- and the general public; and inspire the opportunities for science, policy and prac- bly require a reconsideration of existing co-production of integrated forest–water tice in addressing the forest–water nexus. governance structures and institutional knowledge and solutions. interplays and a move towards more Science cross-cutting multilevel1 or polycentric2 IMPLICATIONS FOR SCIENCE, There is consensus around many of the structures (e.g. Ostrom, 2010; Nagendra POLICY AND PRACTICE physical processes that change the hydro- and Ostrom, 2012). Although such struc- The world continues to lose primary logic cycle and are influenced by forests; tures have been widely advocated and forests: 2017 has been described as the for example, forests affect water infiltration supported in recent years, sufficient atten- second-worst year for tropical tree loss and soil hydraulic properties (Neary, Ice tion is required – and relevant frameworks on record (Curtis et al., 2018), and cur- and Jackson, 2009), and evapotranspira- rent trends and forecasts in the Brazilian tion from forests can influence downwind 1 i.e. Reconciling governing bodies across Amazon are of major concern (INPE, precipitation (Ellison et al., 2017). Existing horizontal or vertical scales of influence, undated). The continuation of deforesta- data and knowledge can assist in priori- from local to national. tion directly conflicts with the ambitions tizing landscape management strategies 2 i.e. Reconciling governing bodies across spatial scales, with multiple centres of and commitments embodied in the SDGs and in identifying water-related eco­system decision-making in a landscape. and other global goals and makes the quest services such as soil erosion control, flood

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A protected forest in Serra do Mar, southeastern Brazil, which helps ensure a sustainable water

supply to São Paulo © ANNA TENGBERG/SIWI

reduction and groundwater recharge. require additional information on water societies (Reed et al., 2017). The impor- The same data can be useful in identi- resources, including current water avail- tance of these ecosystem services, and fying trade-offs where the establishment ability and predictions of future changes of sustainably managing the relationship of forests may be counterproductive to in availability due to climate change and between forests and water, needs to be water needs. Hydrologic processes in for- human and economic development needs. better recognized in forestry, forest and ests change over time (Filoso et al., 2017), An enhanced understanding of current water management strategies, and climate and trees have long lifecycles. Long-term and future water availability and flows and landscape restoration policies, invest- planning is essential, therefore, for forest would help improve the contributions of ments and initiatives. Encouragingly, many and landscape restoration, and this can be forest management and restoration inter- recent international sustainability agendas aided by mapping the potential impacts ventions to water resources (Eriksson et (e.g. those of the UNFCCC, the SDGs and of climate-change projections on water. al., 2018). For example, the effectiveness the Convention on Biological Diversity) An important task is to invest in stud- of restoration in storing carbon is partly explicitly call for the increased integration ies to identify the range of forest–water dependent on adequate soil moisture. of sectors, and the policy environment in interactions and determine how processes International policy processes focused many countries appears to be changing and effects occur at different spatial and on halting deforestation, preventing forest to embrace the concept of integration temporal scales to enable the drawing of degradation and restoring forests are also and to call for engagement across min- general conclusions on suitable manage- important for – as well as reliant on – water istries (O’Connor et al., forthcoming). ment approaches. Local parameters such security. Interventions must therefore be Nevertheless, a more specific focus on the as geography, altitude, forest type, man- context sensitive, and they should take into forest–water nexus is required in national agement regime, scale and season need account technical data on tree species’ and subnational policy development. We to be considered in efforts to improve traits and adaptations (Ilstedt et al., 2016). consider that there is sufficient reliable understanding of highly contextualized information on basic forest–water inter- forest–water relationships (Creed and Policy linkages to start aligning policy around van Noordwijk, 2018). For example, cur- Forest–water provisioning, regulating and them – although awareness is needed of rent investments in landscape restoration cultural ecosystem services are crucial for knowledge gaps, and support processes

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will be important for improving knowledge and practice to understand and sustainably and communities within broader and related policies. manage the forest–water nexus. We rec- socio-ecological systems. New institutional and governance frame- ognize, however, that important gaps exist • In planning future activities, take into works can play key roles in optimizing in current understanding and application. account likely changes in hydrology forest–water management in the face of To our knowledge, no method exists for due to climate change. changing climatic conditions, and a cross- monitoring how changes in landscapes, sectoral approach is fundamental. The including forest losses and gains, relate Non-governmental and security of water, energy and food should to changes in water (and vice versa) at the intergovernmental organizations be core components of forest management scale of a river basin and higher (e.g. in • Analyse the extent to which forest– and the restoration of multifunctional moisture transfer and precipitation form- water interlinkages are recognized in landscapes aimed at achieving SDG 15. ing). A lack of data reduces the capacity NDCs, commitments on forest and Water management would benefit from of managers and policymakers to make landscape restoration, the Aichi Bio- better integration with forest management informed, evidence-based decisions. There diversity Targets and the post-2020 as an NBS to help achieve SDG 6. These is an urgent need to design, implement and Biodiversity Framework. aspects should be incorporated into NDCs learn from landscape approaches that both • Initiate dialogues with donors on and national-level action plans for imple- rely on and influence relationships between financing the implementation of major menting the 2030 Agenda for Sustainable forests and water. We consider this to be forest and water management activi- Development. fundamental for accelerating progress ties under the SDGs, such as restora- towards sustainability goals. Below, we tion initiatives and the management Practice make specific recommendations for future of water ecosystems. Progress in sustainable development is research and action. highly dependent on the management of Communication – all stakeholders the forest–water nexus, given its impli- Decision-makers • Communicate results using a common cations for carbon storage, livelihoods • Integrate forest–water interlinkages terminology and modern information and biodiversity; thus, it is necessary into the climate-change discourse, and communication technologies to to manage forests for water as well as where the concept of “water resilience” reach a wider range of stakeholder for biodiversity, climate and economic could help bridge multiple sectoral groups and sectors. development. In many cases, this will interests (e.g. forests, water, energy and • Reach out to stakeholders at all levels require a fundamental revision of forest agriculture) (Rockström et al., 2014). and connect local and national-level management practices, as well as strong • Give greater attention to the role of stakeholders to relevant international communication, awareness raising and water in climate-change mitigation and fora and dialogue processes relevant capacity building. There is also a need to adaptation in UNFCCC negotiations, to the forest–water nexus, such as the develop new institutional frameworks that the Paris Agreement Road Map, and multilateral environmental agreements foster collaboration on forest and water the NDCs. and World Water Week. management, such as source-to-sea insti- • Promote science-based management tutions that address entire management with an understanding of spatial scale ACKNOWLEDGEMENTS chains (Liss Lymer, Weinberg and Clausen, at multiple levels (i.e. local–national– This article is the result of the Forest Water 2018). Governance considerations, includ- global conditions), as well as issues Champions (FWC) network meetings ing justice, equity, gender, and indigenous of performance, equity and power co-organized by FAO, IUCN and SIWI. rights and knowledge are also crucial for dynamics. The first meeting, in August 2017, hosted managing the forest–water nexus. We • Promote the quantified assessment of 12 experts from the forestry and water propose the development of environmen- performance of integrated landscape sectors from Europe and North America. tal and socio-economic multiple-benefits approaches to study activities and The group of experts had the ambition case studies to help unpack the complexity processes over time, including forest– to establish a consensus on forest–water of the forest–water nexus and to clarify water functions and interactions and issues and to identify joint future activities its multiple benefits for the provision of their socio-ecological effects. to promote the forest–water nexus. The ecosystem services. meeting led to the development of a joint Restoration managers/practitioners statement on forests and water, as well as a CONCLUSION AND NEXT STEPS • Base future activities on landscape report of suggested collaborative activities Attention is increasingly being paid to approaches that recognize the inter- (Springgay et al., 2018). A second FWC integrated approaches in science, policy linkages of land uses, natural resources meeting was held the following year, in

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which some of the original FWC experts Curtis, P.G., Slay, C.M., Harris, N.L., analysis. Forest Ecology and Management, were joined by others. FWC 2 was offi- Tyukavina, A. & Hansen, M.C. 2018. 251: 45–51. cially in the format of a Talanoa Dialogue Classifying drivers of global forest loss. INPE. Undated. TerraBrasilis [online]. Instituto (UNFCCC, 2018) – that is, a facilitative Science, 361(6407): 1108–1111. Nacional de Pesquisas Espaciais (INPE). dialogue between parties to the Paris Ellison, D., Morris, C.E., Locatelli, B., Sheil, [Cited July 2019]. http://terrabrasilis.dpi. Agreement and non-party stakeholders D., Cohen, J., Murdiyarso, D., et al. 2017. inpe.br with the goal of finding consensus through Trees, forests and water: cool insights for a IPCC. 2019. Climate change and land: an transparent, inclusive dialogue. hot world. Global Environmental Change, IPCC special report on climate change, In 2018, the FWC network also organized 43: 51–61. desertification, land degradation, a session at the International Union of Eriksson, M., Samuelson, L., Jägrud, L., sustainable land management, food security, Forest Research Organizations (IUFRO) Mattsson, E., Celander, T., Malmer, A., and greenhouse gas fluxes in terrestrial Joint Conference on Forests and Water in Bengtsson, K., Johansson, O., Schaaf, N., ecosystems. Intergovernmental Panel on Valdivia, Chile. The aim of the session was Svending, O. & Tengberg, A. 2018. Water, Climate Change (IPCC). to share progress within the FWC process forests, people: the Swedish experience in Jones, J.A., Wei, X., Archer, E., Bishop, and to interact with participants on how building resilient landscapes. Environmental K., Blanco, J.A., Ellison, D., Gush, M., to promote actions that integrate science, Management, 62: 45–57. https://doi. McNulty, S.G., van Noordwijk, M. & policy and practice when related to forests org/10.1007/s00267-018-1066-x Creed, I.F. 2019. Forest-water interactions and water at multiple scales, particularly Estrada-Carmona, N., Hart, A.K., DeClerck, under global change. In: D.F. Levia, D.E. the landscape level (see the summary of F.A., Harvey, C.A. & Milder, J.C. 2014. Carlyle-Moses, S. Iida, B. Michalzik, K. the group discussions in Table 2). Here, a Integrated landscape management for Nanko & A. Tischer, eds. Forest-water wider group of stakeholders participated agriculture, rural livelihoods, and ecosystem interactions. Ecological Studies Series No. compared with previous meetings, includ- conservation: an assessment of experience [TBD]. Heidelberg, Germany, Springer- ing participants working in academia, the from Latin America and the Caribbean. Verlag. private sector and non-profit organizations. Landscape and Urban Planning, 129: 1–11. Kusters, K., Buck, L., de Graaf, M., James Dalton acknowledges research Filoso, S., Bezerra, M.O., Weiss, K.C. & Minang, P., van Oosten, C. & Zagt, R. support from the International Climate Palmer, M.A. 2017. Impacts of forest 2018. Participatory planning, monitoring Initiative (IKI) of the Federal Ministry restoration on water yield: A systematic and evaluation of multi-stakeholder for the Environment, Nature Conservation, review. PloS ONE, 12(8): e0183210. platforms in integrated landscape initiatives. Building and Nuclear Safety (BMUB), García-Martín, M., Bieling, C., Hart, Environmental Management, 62(1): 170–181. Germany, grant number 13_II_102. James A. & Plieninger, T. 2016. Integrated Laestadius, L., Buckingham, K., Maginnis, Reed acknowledges research support from landscape initiatives in Europe: multi-sector S. & Saint-Laurent, C. 2015. Before Bonn IKI BMUB, grant number 18_IV_084. u collaboration in multi-functional landscapes. and beyond: the history and future of forest Land Use Policy, 58: 43–53. landscape restoration. Unasylva, 66(245): 11. Hegerl, G.C., Black, E., Allan, R.P., Ingram, Liss Lymer, B., Weinberg, J. & Clausen, W.J., Polson, D., Trenberth, K.E., et al. T. J. 2018. Water quality management from 2015. Challenges in quantifying changes source to sea: from global commitments in the global water cycle. Bulletin of to coordinated implementation. Water References the American Meteorological Society, International, 43(3): 349–360. 96: 1097–1115. https://doi.org/10.1175/ Liu, J., Hull, V., Godfray, H.C.J., Tilman, Carmenta, R. & Vira, B. 2018. Integration for BAMS-D-13-00212.1 D., Gleick, P., Hoff, H., Pahl-Wostl, C., restoration: reflecting on lessons learned from Ilstedt, U., Bargués Tobella, A., Bazié, Xu, Z., Chung, M.G., Sun, J. & Li, S. the silos of the past. In S. Mansourian & J. H.R., Bayala, J., Verbeeten, E., Nyberg, 2018. Nexus approaches to global sustainable Parrotta, eds. Forest Landscape Restoration, G., Sanou, J., Benegas, L., Murdiyarso, development. Nature Sustainability, 1(9): pp. 32–52. London, Routledge. D., Laudon, H., Sheil, D. & Malmer, A. 466. Creed, I.F. & van Noordwijk, M., eds. 2018. 2016. Intermediate tree cover can maximize Morrison, T.H., Adger, W.N., Brown, Forest and water on a changing planet: groundwater recharge in the seasonally dry K., Lemos, M.C., Huitema, D., Phelps, vulnerability, adaptation and governance tropics. Scientific Reports, 6: 21930. J., Evans, L., Cohen, P., Song, A.M., opportunities. A global assessment report. Ilstedt, U., Malmer, A., Verbeeten, E. Turner, R., Quinn, T. & Hughes, T.P. IUFRO World Series, Volume 38. Vienna, & Murdiyarso, D. 2007. The effect of 2019. The black box of power in polycentric International Union of Forest Research afforestation on water infiltration in the environmental governance. 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Nagendra, H. & Ostrom, E. 2012. Polycentric livelihoods in the tropics. Forest Policy and Springgay, E., Dalton, J., Samuelson, governance of multifunctional forested Economics, 84: 62–71. L., Bernard, A., Buck, A., Cassin, J., landscapes. International Journal of the Reid, H., Hou Jones, X., Porras, I., Hicks, Matthews, N., Matthews, J., Tengberg, Commons, 6(2): 104–133. C., Wicander, S., Seddon, N., Kapos, V., A., Bourgeois, J., Öborn, I. & Reed, J. Neary, D.G., Ice, G.G. & Jackson, C.R. 2009. Rizvi, A.R. & Roe, D. 2019. Is ecosystem- 2018. Championing the forest–water nexus Linkages between forest soils and water based adaptation effective? Perceptions – report on the Meeting of Key Forest and quality and quantity. Forest Ecology and and lessons learned from 13 project Water Stakeholders. Stockholm, Stockholm Management, 258: 2269–2281. sites. IIED Research Report. London, International Water Institute (SIWI). O’Connor, A., et al. Forthcoming. The International Institute for Environment and Tengberg, A., Bargues-Tobella, A., Barron, potential for integration? An assessment Development (IIED). J., Ilstedt, U., Jaramillo, F., Johansson, of national environment and development Rockström, J., Falkenmark, M., Folke, K., Lannér, J., Petzén, M., Robinson, policies. C., Lannerstad, M., Barron, J., Enfors, T., Samuelson, L. & Östberg, K. 2018. Ostrom, E. 2010. Polycentric systems E., Gordon, L., Heinke, J., Hoff, H. & Water for productive and multifunctional for coping with collective action and Pahl-Wostl, C. 2014. Water resilience for landscapes. Report no. 38. Stockholm, global environmental change. Global human prosperity. Cambridge, Cambridge Stockholm International Water Institute Environmental Change, 20(4): 550–557. University Press. (SIWI). Power, A.G. 2010. Ecosystem services Rockström, J., Falkenmark, M., Karlberg, Tengberg, A. & Valencia, S. 2018. Integrated and agriculture: tradeoffs and synergies. L., Hoff, H., Rost, S. & Gerten, D. 2009. approaches to natural resources management Philosophical Transactions of the Royal Future water availability for global food – theory and practice. Land Degradation Society B: Biological Sciences, 365(1554): production: the potential of green water for and Development, 29: 1845–1857. https:// 2959–2971. increasing resilience to global change. Water doi:10.1002/ldr.2946 Reed, J., van Vianen, J., Deakin, E.L., Barlow, Resources Research, 45(7). UNFCCC. 2018. Talanoa Dialogue for J. & Sunderland, T. 2016. Integrated Seddon, N. 2018. Nature-based solutions: Climate Ambition – synthesis of the landscape approaches to managing social delivering national-level adaptation and preparatory phase. United Nations and environmental issues in the tropics: global goals. IIED Briefing. London, Framework Convention on Climate learning from the past to guide the future. International Institute for Environment and Change (UNFCCC) (available at https:// Global Change Biology, 22(7): 2540–2554. Development (IIED). talanoadialogue.com/presidencies-corner Reed, J., van Vianen, J., Foli, S., Clendenning, Seddon, N., Turner, B., Berry, P., Chausson, or https://img1.wsimg.com/blobby/go/ J., Yang, K., MacDonald, M., Petrokofsky, A. & Girardin, C.A. 2019. Grounding 9fc76f74-a749-4eec-9a06-5907e013dbc9/ G., Padoch, C. & Sunderland, T. 2017. nature-based climate solutions in sound downloads/1cu4u4230_141793.pdf). u Trees for life: the ecosystem service biodiversity science. Nature Climate contribution of trees to food production and Change, 9: 84 –87.

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R. Lindsay, A. Ifo, L. Cole, L. Montanarella and M. Nuutinen

Peatlands have long been hen Apollo 13 suffered cata- extraordinary exercise in radical thinking unrecognized or ignored, but they strophic failure during its flight and finite resource management. will play a crucial role in climate to the Moon in 1970, initially Given the current situation on Spaceship change and water security and Wthere was confusion and uncertainty. Earth, it is tellingly ironic that the greatest must be a focus of policy and Commander Jim Lovell spotted a “gas” danger facing the Apollo 13 crew during research. leaking into space from the Command their remarkable subsequent voyage was

Richard Lindsay is at the Sustainability Module. An hour later, the Command Mod- a buildup of carbon dioxide (CO2) within Research Institute, University of East London, ule had lost its entire oxygen supply. This their “lifeboat” because the LM’s air fil- London, United Kingdom of Great Britain and Northern Ireland. caused its fuel cells to shut down, leaving ters were unable to process the additional Averti Ifo is at the Université Marien Ngouabi it without power. If the crew had imme- burden of that gas. Spaceship Earth is also Ecole Normale Supérieure, Département des diately been able to identify and plug the experiencing dangerous emissions and an Sciences et Vie de la Terre, Laboratoire de Géomatique et d’Ecologie Tropicale Appliquée, leak, the situation need not have become alarming rise in CO2 concentration. As Brazzaville, the Congo. as critical as it did, but they couldn’t see with Apollo 13, however, even though the Lydia Cole is at the School of Geography & where the emissions were coming from, buildup of CO2 in the Earth’s atmosphere Sustainable Development, University of St Andrews, St Andrews, Scotland, United Kingdom or why. It became clear that, if they were of Great Britain and Northern Ireland. to survive, the Lunar Module (LM) must Luca Montanarella is at the European instead become their lifeboat – although Above: A University of East London research Commission, Joint Research Centre (JRC), the LM was designed to support two men team monitors Plantlife’s Munsary Peatlands Ispra, Italy. blanket bog, Caithness, northern Scotland, Maria Nuutinen is Forestry Officer at the for 45 hours, not three men for 90 hours. United Kingdom of Great Britain and FAO Forestry Department, Rome, Italy. The next four days were to become an Northern Ireland

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is well documented, the emissions leading land-use change and carbon absorbed by characterize peatlands (Figure 2). Based to this Earth-bound crisis are proving just terrestrial ecosystems are both subject to on this carbon content, a peat depth of as difficult to track down. considerable uncertainty (Hansis, Davis only 30 cm contains 327 tonnes of carbon and Pongratz, 2015). This is because per ha; in comparison, primary tropical GLOBAL CARBON EMISSIONS – both are extremely difficult to measure rainforest contains 300 tonnes per ha in ARE WE LOOKING IN THE RIGHT across all the various forms of land-use soil and biomass combined (Blais et al., PLACE? intervention and eco­system response. As 2005). This is because the carbon store The headline figures are simply stated. a pragmatic consequence, the carbon bal- in peat is continuous whereas a forest has According to the latest data from the Global ance of land-use change, in assessing these gaps between trees – it is said, therefore, Carbon Project (Le Quéré et al., 2018), global fluxes, has largely been estimated that you can walk through a forest but only which estimates carbon-flux pathways by quantifying changes in forest cover on a peatland. based on measured atmospheric values, on the assumption that, compared with Carbon density varies between peat- the average annual increase in atmospheric the conversion of grasslands to pastures land types, as well as between different carbon in the period 2008–2017 was 4.7 or croplands, conversion from forest to peatland conditions and even with peat gigatonnes (Gt). Average annual fossil-fuel open land results in far more significant depth. Generally, the deeper the peat and emissions in that period were 9.4 Gt of car- losses of both biomass and soil carbon the less disturbed a peatland system, the bon, and the world’s oceans absorbed some (Houghton, 1999). less dense its carbon content, although 2.5 Gt per year of this. Two other major Although this assumption may hold true this is relative. For example, Warren et al. pathways contribute to this picture of atmo- for most environments, it is certainly not (2012) recorded a fairly consistent value of spheric carbon balance: carbon released the case for peatland ecosystems. The larg- around 60 tonnes of carbon per m3 for three by land-use change, estimated at around est expanses of peatlands occur as open types of Indonesian tropical peatland sys- 1.5 Gt per year, and carbon absorbed by landscapes, and many naturally forested tems ranging in depth from 2.5 m to 12 m, terrestrial ecosystems, estimated as 3.2 Gt, peatlands have been drained to increase and similar carbon densities can be found leaving 0.5 Gt unaccounted for (Figure 1). timber production. The World Reference in temperate-zone peat bogs in Scotland

Atmospheric CO2 concentrations, Base for Soil Resources (WRB) soil clas- possessing several metres of peat in good fossil-fuel emissions and ocean uptake sification (IUSS Working Group WRB, condition. Even with these lower carbon are now relatively well documented, but 2015) shows the extraordinary carbon densities, a peat thickness of just 50 cm is global estimates of carbon emissions from content of the soils (termed histosols) that required at such sites to match the carbon content of tropical rainforest (compared with the 30 cm thickness required for thin- 12 ner, denser peat deposits). Moreover, given the depth of most peatlands (peat depth 10 can extend as much as 60 m below the 8 surface), recent assessments have estimated that, globally, peatland systems contain 6 an average of 1 375 tonnes of carbon per 4 ha – more than four times the carbon stored in an equivalent area of tropical rainforest Gt carbon 2 (Yu et al., 2010; Crump, 2017).

0 Carbon density is one source of varia- tion, but peat depth gives rise to yet further -2 levels of uncertainty. The Harmonized

-4 World Soil Database (HWSD) (FAO/ Fossil-fuel Increased Take-up of Ecosystem Land-use IIASA/ISRIC/ISS-CAS/JRC, 2009) takes emissions carbon carbon by carbon carbon in the the sea take-up emissions atmosphere 1 Measured values Estimated values Budget imbalance Estimated annual carbon fluxes to and from the atmosphere, 2008–2017 Note: Based on documented fossil-fuel emissions, measured atmospheric carbon concentrations, measured carbon concentrations in the oceans, and the estimated take-up by terrestrial ecosystems and emissions from land-use activities; 0.5 Gt carbon is unaccounted for in current measurements and estimates. Source: Global Carbon Project (Le Quéré et al., 2018).

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2 Organic carbon content for FAO-UNESCO 250.0 soil units to 2 m depth

200.0 and their shallow nature renders them more ) 2 amenable to exploitation, degradation and wholesale loss. Tanneberger et al. (2017) 150.0 sought to produce a harmonized map of peatlands in Europe based on data presented

100.0 in the first complete review of peatlands across the continent (Joosten, Tanneberger and Moen, 2017). Both Tanneberger et al. 50.0 (2017) and Joosten, Tanneberger and Moen Organic carbon content (kg/m (2017) chose, however, not to specify a minimum depth of peat for the definition 0.0 of peatland because it was recognized that different thresholds of peat depth had been Acrisols Luvisols Nitosols Podzols Gleysols Fluvisols Histosols RegosolsSolonetzAndosolsVertisols Xerosols Cambisols Ferralsols Greyzems Arenosols Planosols Yermosols applied in different countries, with some Chernozems Phaeozems Solonchaks Podsoluvisols ignoring thin peat altogether. In the United

Note: Peatland soils are histosols, and many extend to significantly greater depths than 2 m. Kingdom of Great Britain and Northern Source: Batjes (1996). Ireland, for example, the figure given by Tanneberger et al. (2017) for that country’s 1 m depth as its reference depth for each unrecognized (Lindsay, 1993). The soils contribution to the European peat map is soil unit because many of the national soil that characterize peatlands are hidden 2.6 million ha, but the relevant chapter in surveys that contribute data to the harmo- below the ground, making it difficult to Joosten, Tanneberger and Moen (2017) nized database have adopted this threshold. distinguish between peatland and non- gives a figure of 7.4 million ha for “peat Consequently, the HWSD is severely con- peatland. In addition, the reputation of and peaty soils” (Lindsay and Clough, strained in its capacity to provide estimates peatlands as unproductive and dangerous 2017). Thus, in the United Kingdom of of peat depth and carbon storage for the wastelands, good only for conversion to Great Britain and Northern Ireland alone, global peatland resource. The HWSD is productive uses, has meant that peatlands the area of uncertainty concerning the true further limited in accurately identifying have also tended to vanish from our col- extent of peatlands amounts to around the true extent of the global peat resource lective cultural consciousness and so have 4 million ha, almost wholly associated because of the relatively coarse scale of become more difficult to recognize. Thus, with thin peat. Assuming a depth of 30 cm mapping and the often small number of peatlands are often labelled as something for this peat, the quantity of carbon stored field samples used to generate the soil other than peatland, with the result that within this single example of uncertainty in survey data. Indeed, if there is a consistent their management causes harm that may one nation’s peatland resource approaches theme running through the underpinning not even be observed. This is dangerous the total estimated annual global emis- literature of peatland extent and global because the failure to recognize an area sions of 1.5 Gt of carbon resulting from carbon flux, it is acknowledgement that as a peatland can lead to unexpected and land-use change. peatland extent and depth are not well sometimes very costly consequences. Such uncertainty is far from unique to documented, and the land-use changes the United Kingdom of Great Britain and associated with peatlands are mostly not THIN PEAT – PERIPHERAL BUT Northern Ireland – it is a global issue. What included in current global atmospheric CRUCIAL does it imply for the extent, condition of, assessments (Houghton, 1999; Houghton, The issue is particularly crucial for thin- and possible emissions from, the global 2003; Houghton et al., 2012). There are ner peats, essentially those with depths of peatland resource? Yu et al. (2010) gave many reasons for this, but the underlying 20–60 cm, not only because they tend to widely quoted estimates of 4.4 million km2 cause is that peatlands are “invisible” – cover significantly more area than deep (3 percent of the global land surface) and both physically and culturally. They have peat but also because they are more easily around 600 Gt of stored carbon for the been dubbed the “Cinderella habitat” confused with other habitats and more known extent of the global peat resource, because they provide so many ecosys- easily destroyed. Thin peat deposits are based largely on documented areas of deep tem services yet continue to go largely consequently more challenging to map, peat. These estimates alone mean that the

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One hectare of peat only 30 cm deep holds as much carbon as 1 hectare of primary tropical rainforest, yet it may be mistaken for other habitats such as heathland and so managed inappropriately. Such a thin layer of peat is more easily destroyed by inappropriate management – the single pass of a plough, for example – than is the case for the loss of the carbon store held in a tropical rainforest, where, even after felling and burning, the roots and stumps of the forest remain. The loss of thin peat does not attract as much world attention as the loss of tropical rainforest, however known global peatland resource contains resulting from destruction through lack of die, their remains accumulate in situ more carbon than all the world’s vegetation awareness, or positively, by halting emis- because waterlogging slows decomposition combined (Scharlemann et al., 2014). The sions, preserving the carbon, bringing back to such an extent that a proportion of this fact that even thin peats (i.e. those peats other ecosystem services and, eventually, plant material and its associated carbon most vulnerable to land-use change) have over longer timescales, restoring the sys- is preserved in what becomes peatland, the potential to release as much carbon per tems once more to carbon sinks. often on millennial timescales. Its water- unit area as the clearing of primary tropi- logged state means that peat is commonly cal forest lends particular urgency to the THE CONSEQUENCES OF PEATLAND as much as 95 percent water by weight need for accurate mapping of these mostly MISMANAGEMENT and 85 percent by volume, meaning that overlooked but potentially very large areas peatlands are significant contributors to of thinner peat. Even small changes in the The release of carbon water control, often at the landscape scale. mapped extent of national and global peat Peatlands are wetlands of major sig- The general land-use trend for these wet resources could mean substantial changes nificance in terms of carbon storage and landscapes, however, has been to drain to the picture of associated carbon fluxes – release because waterlogging preserves them in order to make them more amen­ whether negatively, in terms of emissions dead plant matter. When wetland plants able to exploitation (IPBES, 2018). When

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water is removed from the peat matrix as of Great Britain and Northern Ireland, the also have major implications for carbon a result of drainage, the peat undergoes area of East Anglia known as the Fens emissions (Page et al., 2002) could now significant shrinkage through “primary once consisted of a peatland covering be stimulating greater interest in establish- consolidation” and “secondary compres- 1 500 km2. Records from the seventeenth ing precisely where the peatlands are and sion”, resulting in subsidence of the ground century indicate that this accumulated how best to manage them. In recent years, surface. Moreover, when air penetrates the peat was a key factor in holding back the several substantial peatland systems have normally waterlogged peat it initiates rapid sea from this large drainage basin (Darby, been reclassified as peatland, having previ- decomposition and the release of long-term 1956, p. 107). The wholesale drainage of ously been described as other habitat types. carbon into the atmosphere (“oxidative the area in the eighteenth and nineteenth wastage”), giving rise to carbon emissions centuries by “adventurers” (whom today REGIONAL STATUS OF PEATLAND as well as further ground subsidence. might be called financial speculators) to MAPPING FOR CARBON, WATER It is unfortunate, therefore, that the grow arable crops on the rich peat soil has AND BIODIVERSITY drainage of such systems is inadequately since given rise to some of England’s finest Substantial progress has been made in captured in the present global atmo- agricultural land. There has been a signifi- peatland mapping and the development spheric model of carbon fluxes in terms cant price to pay, however, beyond the loss of policy processes in the last decade or of emissions due to land-use change in of the area’s formerly rich biodiversity. The so, as illustrated by the examples below. peatlands (Houghton et al., 2012). Such peat soils subject to intensive agriculture Nevertheless, there are likely many more emissions could be significantly larger than release as much as 8 tonnes of carbon per areas of overlooked peatlands awaiting dis- shown in Figure 1 but in that case they ha annually through oxidative wastage covery, particularly in Africa but also areas must also be balanced by greater carbon (Evans et al., 2016), and the ground surface of thin peat on every continent currently capture than indicated, resulting in the has subsided to such an extent that many classed as something other than peatland.

same overall rise in atmospheric CO2. areas are now as much as 3 m below sea

Should this additional take-up of CO2 by level. Continued farming is only possible The Congo’s vast peatlands terrestrial ecosystems begin to fail as a because of substantial and very expensive Deep in the Congo Basin, in an area that is result of climate change, however, emis- drainage infrastructure, and the cost is now enormously difficult to access, a peat-bog sions from land-use change could take so high, and the threat of rising sea levels system was brought to light only recently on considerable added importance. The and subsiding ground levels so serious, by scientific collaboration among sev- main alternative source of estimates for that the country’s Environment Agency is eral teams of researchers. This peatland emissions due to land-use change are the discussing the need to move entire com- complex is now recognized as the largest data collated from the individual national munities to safer ground in the foreseeable known continuous peat-bog system in the greenhouse-gas accounting reports sub- future (UK Environment Agency, 2019). tropics, at almost 145 000 km2, two-thirds mitted under the Kyoto Protocol. The Similar issues are being discussed in of which is in the Democratic Republic of guidance provided to those assembling coastal areas of Southeast Asia, where the Congo and the remaining one-third in these national reports (Intergovernmental extensive peatlands have been converted the eastern part of the Congo (Dargie et Panel on Climate Change, 2014) has wid- to major rice projects and, more recently, to al., 2017). The area is so enormous that it ened to include procedures for estimating oil-palm and acacia plantations; this has led encompasses two very large Ramsar sites, carbon emissions from peatland systems to widespread peatland fires, and peatland Lac Télé in the Congo and Ngiri-Tumba- subject to, for example, drainage for agri- subsidence is in danger of causing huge Maindombe in the Democratic Republic cultural purposes. Even the collation of areas of coastal flooding (Hooijer, 2012). of the Congo, the latter being the world’s this information provides only a partial These and other problems have arisen time second-largest Ramsar site. The known picture, however, because some nations and time again, either because there was extent of the newly identified peatland do not participate and all nations have a failure to recognize that an area was a area amounts to almost 4 percent of the difficulty in deciding the area over which peatland or because the consequences of Congo Basin (the world’s second-largest the particular peat-related emission factors exploiting the peatland were insufficiently river basin). With measured peat depths should be applied because the extent of understood. Both these reasons continue of 0.3–5.9 m, the recorded peatland area peatlands is so poorly known. to represent major challenges worldwide, is estimated to contain 30 Gt of carbon; and even major deposits of deep peat have thus, this peatland system contains nearly The problem of subsidence continued to be overlooked, misclassified 5 percent of the carbon contained in the Peat subsidence itself gives rise to undesir- or subsumed under some other habitat type world’s known peatlands. This peatland able consequences beyond those of carbon (as explored below). On the other hand, plays an essential role in the regional loss. In the lowlands of the United Kingdom growing recognition that such actions climate of the Congo Basin and makes a

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significant and active contribution to the catchment dynamics of the Congo River, which is second only to the Amazon in the volume of its discharge. The peatland complex constitutes a huge reservoir of freshwater and, because it so large that it often covers entire interfluves, it is a key water source for various tributary systems (e.g. the Oubangui and Sangha) that flow through this vast ecological zone. Driven by concerns about the potential impacts of climate change in the region, researchers in the CongoPeat project are seeking to understand how the peatlands originally developed and what has main- tained them as waterlogged, peat-forming systems for the past 10 000 years or so, thereby enabling the establishment of the area’s exceptional biodiversity. In addi- tion to preparing preliminary maps of the peatlands to enable improved land-use planning, the CongoPeat team is attempt- ing to understand the water balance of these systems because the majority appear to be water-shedding, meaning they rely solely on direct precipitation inputs for their water supply (i.e. they are ombrotro- phic bogs). In such systems, losses from evaporation and drainage by gravity flow must be balanced by precipitation inputs, and there may be significant consequences if these inputs and outputs are altered by a regional decline of rainfall or longer-term climate change. Given that the Congo peatlands rely on the basin’s overall rainfall pattern, it is significant that recent recorded data and publications on rainfall in the (Republic of the) Congo have shown a marked decline in rain inputs. This is probably partly due to deforestation but mainly to recent negative trends in atmo- spheric and oceanic parameters: that is, the Atlantic Multi-Decadal Oscillation, the North Atlantic Oscillation and the Southern

Oscillation Index (Ibiassi Mahoungou © L. COLE et al., 2017; Ibiassi Mahoungou, 2018). Local people receive training on the use Particularly in light of these trends, impor- lost through evaporation, evapotranspira- of a mobile-phone-based application for collecting information on Mauritia tant questions need to be answered: How tion and lateral drainage? flexuosa productivity in a palm swamp much rainfall is required to maintain satu- In addition to studies aimed at determin- (regionally known as an aguajal) in the rated conditions? And how much water is ing the water balance, field surveys have PMFB, western Amazonia

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revealed the exceptional biodiversity of these peatlands, including iconic species such as the forest elephant and hippopota- mus. The three large African primates – gorillas, chimpanzees and bonobos – all have significant populations there (Fayet al., 1989; Fay and Agnagna, 1992; Blake et al., 1995), and the region supports more than 350 bird species, including a number of endemic species (Evans and Fishpool, 2001). This highlights the fact that, because peatlands are so often overlooked, the remarkable and often highly distinctive biodiversity they support also remains hidden or is assumed to be dependent on other habitat types whereas peatlands may actually constitute the core habitat areas for certain key species (e.g. Singleton and van Schaik, 2001; Baker et al., 2010). Resources spent on maintaining habitats assumed to be vital for this biodiversity may be wasted if the true core habitat features are lost in the meantime through misplaced actions.

Peatlands in the Amazon A similar story of discovery has unfolded in the world’s largest river basin, the Amazon, in the last few decades. Some of the first published studies on the peatlands of the Pastaza-Marañón Foreland Basin (PMFB) in western Amazonia in the northern Peruvian lowlands described a peat-rich area of approximately 100 000 km2 con- taining 2–20 Gt of carbon (Lähteenoja et al., 2009). Since then, research has been carried out to refine these estimates and to understand more about the area’s developmental processes (Roucoux et al., 2013; Kelly et al., 2017) and eco­system characteristics (Draper et al., 2014, 2018). Understanding the interannual flood variability, associated environmental disturbances and river-channel dynamics of the Amazon Basin is key to under- standing the development of its peatlands

(Gumbricht et al., 2017). Such factors have © L. COLE created a complex arrangement of environ- A palm swamp (aguajal) ments that are waterlogged throughout the Unlike in Southeast Asia, where coastal dominated by Mauritia flexuosa in the PMFB, western Amazonia year and thus ideal for the development of domes are the dominant form in which peatlands (e.g. Householder et al., 2012). peat is found (Dommain, Couwenberg and

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The carnivorous sundew Drosera binnata on the margin of a peat pool formed within a patterned fen peatland near Moon Point, Locally, peatlands are often referred to as interannual flooding variability of the Fraser Island, Australia “sucking” environments (chupaderas in basin’s rivers, with waters rising in some Spanish), illustrating the lived experience places by up to 10 m, means that draining Joosten, 2011), many of the PMFB’s peat- of traversing them. the peatlands would be near-impossible. lands are small, discrete and transient over Although large and significant, the The lack of a coherent road network geological timescales. To date, depths of up PMFB is just one of the basins in the also prevents the overland transportation to 7.5 m have been found (Lähteenoja et al., Amazon that contains peat. Others have of machinery and human resources to 2009), covered by vegetation communities been classified in the eastern Amazon in support industrial-scale drainage. Plans to varying from open grass and sedge-rich Peru (Householder et al., 2012) and in the greatly extend the regional infra­structure ecosystems to pole forests and palm Brazilian Amazon (Lähteenoja, Flores and enhance extractive capabilities in swamps, where one particular palm of and Nelson, 2013), and there are probably the future, however, would increase the economic value, Mauritia flexuosa, com- many more, currently “invisible” areas vulnerability of the peatlands of the monly dominates (Lähteenoja et al., 2009). that need to be formally identified and PMFB and beyond (Roucoux et People living in and around the peatlands classified and which are subject to various al., 2017). The challenge for the of the PMFB classify and use these ecosys- threats. Compared with the situation in scientific community is to evalu- tems in various ways (Schulz et al., 2019), Southeast Asia (Page and Hooijer, 2016), ate the contributions that Amazonian although they tend to avoid them when many of the Amazon’s peatlands are rela- peatlands make to carbon and water alternative landscape types are available tively intact and under limited immediate cycling, thought to be of huge (L. Cole, personal communication, 2019). threat of drainage or conversion. The significance on a local to global scale

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(Gumbricht et al., 2017), before such con- Despite the continued efforts of the it should be possible to find at least tributions are compromised. European Union member states and policy- some places where the rod or stick can makers to reverse the trend and protect and be made to penetrate to a depth of at Fraser Island’s newly discovered restore peatlands and other wetlands and least 30 cm with relative ease. peatland avoid their continued drainage and degra- 2. Take a sample from a depth of On Fraser Island off the coast of the dation, little research exists on the direct 20–30 cm, air-dry the sample and see Australian state of Queensland, areas for- effectiveness or cross-sectoral impacts of if it will burn. The high organic matter merly classified as relatively uninteresting the numerous interventions. The European content of peat means that, once dry, “wet heath” have now been acknowledged Union’s environmental laws and incentive it should ignite readily.1 as highly distinctive peatland systems that schemes, particularly those linked to the Perhaps the greatest challenge in support a significant number of endangered Natura 2000 framework, have established determining the true extent of peatlands species (Fairfax and Lindsay, forthcom- a strong protection regime for peatlands, identified through surveys is the resolution ing). Having previously been excluded but other legislative frameworks, including used. If a small pocket of peat measuring from the Fraser Island World Heritage Site, the Common Agricultural Policy and the 100 m × 100 m (i.e. 1 ha) × 30 cm deep can these peatlands may now be incorporated renewable-energy policy, have arguably contain as much carbon as the same area of in it as important ecosystem components. yielded opposite effects by providing primary tropical rainforest, there is evident With sympathetic management, the peat- perverse incentives. The specific effects benefit in ensuring that the mapping resolu- lands also have the potential to be valuable of the European Union’s climate policy tion is sufficiently fine to identify areas carbon sinks and key hinterland providers frameworks on peatlands have not yet been of this size. Ideally, therefore, mapping of iron-rich waters to support the role of fully addressed (Peters and von Unger, would be undertaken at a scale of 1:10 000, coastal mangroves as nursery grounds for 2017). A new effort may be initiated, how- but for large areas a scale of 1:20 000 local fish populations. ever, in response to a recent resolution by may be the highest resolution achievable the United Nations Environment Assembly with current technology and available Peatlands in Europe (2019), which calls for more emphasis on resources. Tanneberger et al. (2017) estimated the the conservation, sustainable management area of peatland in Europe at 593 727 km². and restoration of peatlands worldwide, Recommendations for policymakers Mires, which by definition are dominated as also recommended in a recent assess- Policymakers should: by living and peat-forming plants, were ment by the Intergovernmental Platform • Verify whether it is likely that more found to cover more than 320 000 km² for Biodiversity and Ecosystem Services peatlands would be found in the (around 54 percent of the total peatland (IPBES, 2018). country. area). If shallow peatlands (< 30 cm • Prioritize the mapping of peatlands at peat) in the European part of the Russian CONCLUSIONS a scale of at least 1:20 000 but ideally Federation are included, the total peat- Here, we make some simple recommenda- 1:10 000. land area in Europe is more than 1 million tions for improving understanding of the • Map past, ongoing and planned man- km2 – almost 10 percent of the total land true extent of peatlands on the planet – the agement (“activity data”, under the area. Peatlands are distributed widely first step in their protection, for all the United Nations Framework Conven- among the European Union countries, benefits this will bring. tion on Climate Change), including with concentrations in northern, central existing drainage infrastructure and and eastern Europe (Germany, Ireland, the Recommendations for action – finding other livelihood activities in the area Netherlands, Poland, the United Kingdom the peat (e.g. fishing and peat extraction). of Great Britain and Northern Ireland, and Two simple steps can be used to determine • Include peatland maps in planning pro- the Nordic and Baltic countries). Official whether you are standing on peat: cesses from the local to the regional policy research efforts, political appraisals 1. Peat is a relatively soft soil, so it should scale, not only for climate and bio- and firm legislative provisions exist that be possible to push a rod or stick with diversity benefits but also for water recognize the need to protect peatlands a diameter of 6–8 mm at least 30 cm security and disaster risk reduction. and the inherent vulnerability of their into the soil using only hand pressure. • Protect undrained peatlands to avoid soils. In practice, however, the degrada- We use a length of 6-mm-diameter activities that might cause important tion of these ecosystems is continuing threaded steel rod – widely available 1 across the European Union, due mainly around the world. This may not work Note that soils containing agrochemical residues can release noxious or toxic to drainage for agriculture and forestry and so easily in some tropical peats that fumes when heated. Please take suitable peat extraction for fuel and horticulture. consist largely of wood but, even so, precautions.

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changes to their hydrology and associ- The next generation looks to us to sequestration of tropical peat domes in south- ated ecosystem services. address the challenge of climate change east Asia: links to post-glacial sea-level • Budget for the restoration of drained so that they, and Spaceship Earth, can changes and Holocene climate variability. peatlands and for documenting and survive. Because, for them, there is no Quaternary Science Reviews, 30(7–8): developing drainage-free livelihood LM, there is no lifeboat, there is no 999–1010. options. alternative. u Draper, F.C., Honorio Coronado, E.N., • If peatland drainage continues, invest Roucoux, K.H., Lawson, I.T., Pitman, in the development of systems for fire N.C.A., Fine, P.V.A., Phillips, O.L., Torres risk assessment, fire reduction and fire Montenegro, L.A., Valderrama Sandoval, management. E., Mesones, I., García-Villacorta, R., • Harmonize incentives, laws and law Ramirez Arévalo, F.R. & Baker, T.R. enforcement to support these goals. References 2018. Peatland forests are the least diverse • Communicate to all decision-makers, tree communities documented in Amazonia, stakeholders and the public the impor- Baker, J.R., Whelan, R.J., Evans, L., Moore, but contribute to high regional beta-diversity. tance of peatlands for water, biodiver- S. & Norton, M. 2010. Managing the ground Ecography, 41, 1256–1269. sity and climate change. parrot in its fiery habitat in south-eastern Draper, F.C., Roucoux, K.H., Lawson, I.T., • Monitor the status of peatlands to Australia. Emu: Austral Ornithology, 110(4): Mitchard, E.T.A., Honorio Coronado, detect potential signs of emerging 279–284. E.N., Lähteenoja, O., Torres Montenegro, drainage-based land uses and land- Batjes, N.H. 1996. Total carbon and nitrogen L., Valderrama Sandoval, E., Zaráte, R. use impacts. in the soils of the world. European Journal & Baker, T.R. 2014. The distribution and • Report on the status of peatlands of Soil Science, 47: 151–163. amount of carbon in the largest peatland against the Sustainable Develop- Blais, A.M., Lorrain, S., Plourde, Y. & complex in Amazonia. Environmental ment Goals and under international Varfalvy, L. 2005 Organic carbon densities Research Letters, 9(12). conventions. of soils and vegetation of tropical, temperate Evans, C., Morrison, R., Burden, A., and boreal forests. In: A. Tremblay, L. Williamson, J., Baird, A., Brown, E., Final thoughts Varfalvy, C. Roehm & M. Garneau, eds. Callaghan, N. et al. 2016. Lowland peatland Spaceship Earth is not a new concept, Greenhouse gas emissions — fluxes and systems in England and Wales – evaluating but, around the globe, young people’s processes, pp. 155–185. Environmental greenhouse gas fluxes and carbon balances. active responses to the climate protest of Science. Berlin, Germany, Springer. 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Fire, forests and city water supplies

D.W. Hallema, A.M. Kinoshita, D.A. Martin, F.-N. Robinne, M. Galleguillos, S.G. McNulty, G. Sun, K.K. Singh, R.S. Mordecai and P.F. Moore

The changing role of fire in forest orest landscapes generate 57 percent landscapes shows that strategic of runoff worldwide and supply forest management is necessary to water to more than 4 billion peo- safeguard urban water supplies. Fple (Millennium Ecosystem Assessment, 2005). As the world population continues Dennis W. Hallema ([email protected]) and Mauricio Galleguillos is Assistant Professor at to increase, there is a strong need to under- Ge Sun are Research Hydrologists at the United Universidad de Chile, Santiago, Chile. stand how forest processes link together States Department of Agriculture (USDA) Steven G. McNulty is Director of the USDA Forest Service Southern Research Station, North Southeast Regional Climate Hub, North in a cascade to provide people with water Carolina, United States of America. Carolina, United States of America. services like hydropower, aquaculture, Alicia M. Kinoshita is Associate Professor of Kunwar K. Singh is Research Fellow at North drinking water and flood protection (Car- Water Resources Engineering at San Diego State Carolina State University, Raleigh, North University, California, United States of America. Carolina, United States of America. valho-Santos, Honrado and Hein, 2014). Deborah A. Martin is Research Hydrologist Rua S. Mordecai is Science Coordinator at the Emeritus at the US Geological Survey (retd.), United States Fish and Wildlife Service, Raleigh, Boulder, Colorado, United States of America. North Carolina, United States of America. Controlled burns promote forest health by François-Nicolas Robinne is Postdoctoral Peter F. Moore is Forestry Officer at the FAO cleaning up fuels and promoting tree growth, Fellow at the University of Alberta, Edmonton, Forestry Department, Rome, Italy. with indirect benefits for the quality of forest Alberta, Canada. water resources © DENNIS HALLEMA, FOREST USDA SERVICE SOUTHERN RESEARCH STATION

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1 Global wildfire risk to water security based on fire activity, vegetation, geography, water availability and socio-economic development

Note: Wildfire risk to water security is shown on a scale from 0 (minimum risk) to 100 (theoretical maximum risk potential). Source: Robinne et al. (2018), used here under a CC BY 4.0 licence.

Wildfire is a major disturbance affecting are conducive for another fire. less water immediately after fire and, in forested watersheds and the water they Extreme and hazardous wildfires, on the environments influenced by snow, more provide (Box 1) (Paton et al., 2015). Several other hand, can cause erosion, gullying, snow can accumulate in forest clearings regions have experienced shifts in wildfires soil loss and flooding – and, in severe (Kinoshita and Hogue, 2015; Hallema et from natural ignition sources (primarily cases, even debris flows and flash floods al., 2019). Therefore, accounting for wild- lightning) to ignitions dominated by human – by removing the protective functions fire impacts on forests in water planning activities, especially in areas where popu- of forests on hillsides (Ebel and Moody, has become a priority for the nexus of fire, lations are increasing (Moritz et al., 2014; 2017). Extreme wildfires have become water and society or, in other words, the Balch et al., 2017). Occasional wildfire is more common after decades of fire sup- connection between fire risk and water essential for the health and functioning of pression, allowing forests to become much security (Figure 1) (Martin, 2016). In this fire-adapted ecosystems through its effects denser with vegetation and causing more article, we discuss managed forest land- on nutrient cycling, plant diversity and fuels to build up over time. Combined with scapes as nature-based solutions for water succession, and pest regulation (Pausas increasing summer drought, this can have and explore how fire affects the provision and Keeley, 2019). It also reduces the risk impacts on water yield and the ability of of water-related services. of subsequent wildfires until a forest has upstream forests to deliver high-quality accumulated sufficient fuels and conditions water because forest vegetation uses WATER SERVICES FROM FORESTS In many areas, swimming in a river, Box 1 preparing food and irrigating the garden Key facts on fire and forest water resources have a commonality: they rely on water services provided by upstream forests (Sun, • Globally, an average of 400 million ha of land was burned annually in the period 2003–2016, Hallema and Asbjornsen, 2018). Water of which an estimated 19 million ha per year was forest (Melchiorre and Boschetti, 2018). ecosystem services, also called hydrologic • Tropical forests represent the largest proportion of forested area burned (65.9 percent services, provide a range of direct and between 2003 and 2016) (Melchiorre and Boschetti, 2018). indirect benefits and associated values. • Wildfires in the United States of America result in up to 10 percent more surface water Most forest hydrologic services – such annually – and 10–50 percent more in regions with severe wildfires (Hallemaet al., 2019; as hydropower generation, power plant Kinoshita and Hogue, 2015). cooling, irrigation, aquaculture and flood • Ninety percent of the world’s cities with populations larger than 750 000 use water from mitigation – can be expressed in terms of forested watersheds, yet nine out of ten of these watersheds show signs of water-quality a market value. Some services, however, degradation (McDonald et al., 2016). have intrinsic, non-market values, such as • Controlled burns (also called prescribed fires) clean up dead vegetation and reduce the aquatic ecosystem quality and biodiversity, likelihood of extreme wildfires that can contaminate forest water supplies. Studies show or they provide benefits to society that are that controlled burns do not degrade water quality compared with wildfires (Fernandes not easily quantified, such as opportunities et al., 2013). for recreation, religious connection and aesthetic enjoyment (Hallema, Robinne and Bladon, 2018).

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Box 2 Longleaf pine restoration increases surface water delivery in the Altamaha River basin in Georgia, United States of America Longleaf pine (Pinus palustris) coverage in the southeastern Coastal Plain region of the United States of America declined in past centuries from 372 000 km2 to 17 000 km2 due to agricultural conversion and replacement with loblolly pine (Pinus taeda) plantations. Natural longleaf pine forest grows as savanna, with lower evapotranspiration, lower water demand and greater drought tolerance than dense loblolly pine for- est. To assess the potential impacts of longleaf pine restoration on water, we simulated the 36 670 km2 Altamaha River basin for the period 1981–2010 using the Soil Water Assessment Tool. We compared water balances for the existing mixed land-use situation (34.3 percent ever- green forest, 23.5 percent farmland, 22.1 percent deciduous forest, 11.6 percent wetland forest and 8.5 percent urban) with a scenario in which all farmland was converted to loblolly pine (maximum seasonal leaf area index 5.0; Sampson et al., 2011) and another scenario in which all farmland was converted into open longleaf pine savanna (leaf area index 2.0; Kao et al., 2012). The mixed land-use situation and the loblolly pine and longleaf pine scenarios provided 486 mm, 430 mm (11.4 percent) and 498 mm (2.6 percent) of water yield, respectively, for 1 185 mm average annual precipitation. Evapotranspiration was 671 mm (reference), 729 mm (8.6 percent) and 658 mm (2.0 percent), respectively. Given declining annual precipitation and increased summer drought in the Southeast Region of the United States of America, a primary land man- agement objective of longleaf pine restoration, combined with prescribed burning, would have a positive impact on surface water supplies. © BRIAN BROWN, VANISHING SOUTH GEORGIA SOUTH BROWN, VANISHING © BRIAN © DENNIS HALLEMA, FOREST USDA SERVICE SOUTHERN RESEARCH STATION

Natural longleaf pine savanna in the southeast of the United Upstream forest restoration efforts have the potential to States of America has an open canopy and does not consume as increase streamflow in the Altamaha River in Georgia, much water as much denser loblolly pine forests United States of America

Under the right conditions, forests that 82 percent of the global population water quality due to upstream disturbances. can supply high-quality drinking water uses water from upstream areas faced Overall, the ongoing decline in with minimal treatment. A substantial with high levels of threat (Green et al., water quality is concerning, given accel- part of the cost of water supply is gener- 2015). Remediation and purification erating trends in urbanization and water ally associated with water purification efforts to safeguard water quality benefit demand (Sun, Hallema and Asbjornsen, (Millennium Ecosystem Assessment, 2005); 75 percent of the population, but these ben- 2017), and it raises the question of surface water supplies from undisturbed efits are unequally distributed: industrial how the cost of watershed protection and forests that yield high-quality water countries reduce freshwater threats by aquifer recharge can be reduced (Muñoz- usually have lower treatment costs 50–70 percent, while countries with Piña et al., 2008). In some cases, forest compared with water from other sources lower gross domestic products reduce restoration could lead to an increase in (García Chevesich et al., 2017). threats by less than 20 percent (Green et water supplies in the long term, even if It’s easy to take clean water for granted al., 2015). it does not specifically target water ser- when it is available in abundance. Nearly This disparity is linked not only to politi- vices (Box 2). all forest watersheds are subject to some cal and economic factors but also to the degree of human activity, however, degree of urbanization. Rapidly growing and water scarcity and water impair- water-dependent urban centres are likely ment are widespread. It is estimated to experience an increased risk of impaired

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WILDFIRE IMPACTS ON WATER Box 3 SUPPLY SERVICES Post-wildfire erosion in Chile and concerns for water supplies Although wildfires have beneficial effects South-central Chile experienced major wildfires in 2017 that burned more than 5 000 km2. on forest landscapes, the outcome can An unusually hot spring season combined with prolonged drought (Garreaud et al., 2017) be very different for extreme wildfires triggered a series of fire storms. Approximately half of these occurred in radiata pine (Pinus that consume forest stands – including radiata) plantations, and most were ignited by humans. In addition to the devastating effects canopies – in their entirety. Wildfires tend on the human population and regional economy, there are serious concerns for biodiversity, to increase storm runoff in the months after given that some burned areas are already on the International Union for Conservation of a fire and boost the water yield from burned Nature’s Red List of ecosystems in critical danger of collapse (Alaniz, Galleguillos and landscapes for several years (Kinoshita Perez-Quezada, 2016). The 2017 wildfires have increased erosion rates, even removing the and Hogue, 2011; Kinoshita and Hogue, entire topsoil layer in some areas. This has led to the compaction of the now-exposed lower 2015; Hallema et al., 2017b; Hallema et al., soil layers due to the combined effect of relatively short forest rotation cycles (with as little as 2018). They also have profound impacts 20 years between harvests) and the higher impact force of raindrops on the now unvegetated on the water purification functions of – and unprotected – soil surface (Soto et al., 2019). The phenomenon has reached a stage at watersheds by changing the timescales which no more loose sediment is available for erosion, and the soil is effectively depleted. and pathways of water movement through The concerning impact of wildfire in Chile shows the urgency of integrating water-related landscapes and increasing the availability issues in sustainable forest management. It also demonstrates the need to further investigate of readily transported material such as post-fire drainage issues and dissolved chemicals and suspended sediments that affect treatment wildfire ash (Hallemaet al., 2017a; Murphy processes for municipal water supplies (Odigie et al., 2016). et al., 2018). Wildfire ash contains trace metals, nutrients and organic material from branches, leaves and needles that can com- promise water treatment for domestic uses. Precipitation drives the transportation of contaminants, ash and eroded soil down- hill, resulting in pulses of increased stream levels immediately following rainstorms (Ice, Neary and Adams, 2004). Combined with the loss of riparian veg- etation and increased sediment loads in streams, severe wildfires degrade aquatic habitat and affect fisheries, which provide © MAURICIO GALLEGUILLOS, UNIVERSIDAD DE CHILE important hydrological services and fulfil vital economic roles in many parts of the Intense fire storms in south-central Chile in 2017 caused a major loss of Pinus radiata world. Locally, increased stream tempera- forest cover tures and toxicity from ash, fire retardant and polluted sediments are direct causes sediment reduces the capacity of reservoirs piping, pumps and filtration equipment, of mortality among fish and other aquatic to store water, and adsorbed nutrients like and stabilizing streambanks and hillslopes organisms (Dunham et al., 2007). phosphorus can promote algal growth – can cost millions of dollars (Box 4). Degraded surface runoff can be conveyed (Smith et al., 2011). Studies in Australia towards water intakes and water-storage and Chile have observed that fire-affected A HEALTHY FIRE REGIME FOR reservoirs, often located at considerable water contains dissolved chemicals and SUSTAINABLE FORESTS AND distances downstream from burned water- suspended sediments that affect treatment WATER SUPPLIES sheds. For example, runoff from the 1996 processes for municipal water supplies Forests are resilient to and often benefit Buffalo Creek Fire in Colorado, United and has the potential to affect human from fire, which promotes new growth States of America, travelled more than health (White et al., 2006; Odigie et al., and species diversity and increases their 15 km from the burned area to a down- 2016) (Box 3). Measures to restore water natural ability to improve water quality by stream reservoir (Moody and Martin, supply infrastructure after wildfire and soil filtration. Forests burned by extreme 2001). Floating debris clogs water intakes post-wildfire flooding – such as remov- wildfire ultimately recover the capacity to and hydroelectric-generation equipment, ing sediment from reservoirs, repairing provide clean water, but the process can

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Box 4 Degraded post-wildfire water quality in urban water systems in California, United States of America

The state of California is experiencing increasing fire risk due to warmer and drier conditions, yet urban development continues to encroach on surrounding wildlands, exposing residents to growing primary and secondary fire hazards. The October 2017 North Bay wildfires in the San Francisco Bay Area caused 46 fatalities and the loss of thousands of structures. These extreme fires, also known as the Northern California Firestorm, constitute one of the state’s costliest disasters. One of the fires, the Tubbs Fire, damaged the drinking-water system, resulting in elevated levels of benzene and other contaminants to the extent that a local “do-not-drink/do-not-boil” water-quality advisory was maintained until one year after the fire. In Northern California, drinking water in the city of Paradise became contaminated with benzene after the 2018 Camp Fire, when burned plastics, soot and ash leaked into the water system. It is estimated that it could take two years and cost USD 300 million to restore the system’s water quality. These examples highlight the detrimental impacts of major wildfires on water quality and demonstrate the need to protect drinking

© ZACK MONDRY, USDA FOREST USDA © ZACK MONDRY, SERVICE water from future wildfires. A severe wildfire in California destroyed much of the chaparral vegetation, leading to erosion and increased sediment input in surface water

take many years (Robichaud et al., 2009). the resilience of forest water supplies (Robinne et al., 2016). As the timing, Sustainable forest planning and manage- (Kinoshita et al., 2016; Hallema et al., magnitude and interaction of wildfires, ment can mitigate the adverse impacts of 2019). droughts and insect infestations continue extreme wildfires while helping maintain The future reliability of water supplies to change, additional alterations to forest forest health and safeguarding forest water also depends on forest structure and veg- structure and function can be expected. services (Postel and Thompson, 2005). A etative composition and their interactions More research is needed to better under- healthy fire regime is the cornerstone of a with ecosystem processes (Thompson et stand the precursors of these unprecedented sustainable forest and therefore a sustain- al., 2013). Increasing variability in air events to allow land managers to develop able water supply (Figure 2). Promoting the temperature, precipitation, land use and and apply adaptive conservation practices use of prescribed fire in watersheds can chemical deposition (nitrogen and sulphur) aimed at increasing hydrological resilience reduce the likelihood of extreme wildfires is creating unprecedented combinations to forest disturbance. and the consequent contamination of for- of ecosystem stress (McNulty, Boggs est water supplies (Boisramé et al., 2017). and Sun, 2014), which can contribute to SAFEGUARDING FUTURE WATER Given predictions that wildfires will changes in fire regimes and water cycles RESOURCES increase in frequency, intensity and size in that are difficult to predict. In Cape Viewing the fire, water and society nexus future climate regimes linked with increas- Province, South Africa, for example, the as a dynamic process helps in identify- ing drought, scientists, policymakers and introduction of non-native acacias, euca- ing high-priority issues for scientists, managers must coordinate their efforts in lypts and pines has increased fuel loadings, land managers and water providers. The fire preparedness (warning systems), fire leading to increased fire risk (Kraaijet al., importance of this dynamic interaction is impact planning and post-fire risk assess- 2018) and the possibility of post-fire water reflected in the International Association ment to anticipate the potential post-fire quality effects. of Hydrological Sciences’ decadal impacts on water. A good understanding Ultimately, increasing fire frequency and (2013–2022) research theme, Panta Rhei of fire trends, impacts and environmental severity affect the quality and quantity (“everything flows”). Forest disturbances interactions is essential for maintaining of forest water resources at broad scales accumulate downstream, and therefore the

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MARKET NON-MARKET EROSION DRINKING WATER AQUATIC ECOSYSTEM FLOODING QUALITY FUEL TREATMENTS HYDROPOWER CONTAMINATION WITH (PRESCRIBED BURNING) METALS, NUTRIENTS, ASH POWER PLANT BIODIVERSITY, REFORESTATION COOLING RECREATION RESERVOIR POLLUTION ADAPTIVE IRRIGATION, RELIGIOUS, CONSERVATION AQUACULTURE AESTHETIC FLOOD MITIGATION

2 Wildfires can have a severe impact on water services, but much of this impact may be mitigated by fuel treatment and other forest solutions for water (Robinne et al., 2018) consumed by fire. The challenge is that management practices and to integrate a more fundamental every fire has unique circumstances, and understanding of interactions between ground data are scarce. future of water resources is the inevitable wildfires, reforestation/afforestation, and The trend of increasing urbanization will sum of natural and human impacts and the supply of and demand for hydrological lead to more deforestation and increase their interactions and feedbacks. services (Box 5). pressure on forest hydrologic services. The quality of water-supply predictions Expanding the area of study from the Two-thirds of the global population is depends in large part on the quality of local to regional scale has major implica- expected to reside in urban areas by 2050, data and models. The wealth of satellite tions for the number of interactions that with most growth concentrated in Africa, data on wildfires, climate and forest inven- must be taken into account. To quantify Asia, Latin America and the Caribbean tory collected in recent years has enabled fire risk to water security, for example, (UN-Habitat, 2018). The land area covered the building of predictive models of fire it is necessary to identify “at risk” for- by cities is predicted to triple, and more impacts on water. Few datasets exist, ests where active management is needed people are expected to move into the transi- however, on post-fire water quality, and to safeguard water supplies and public tion zone between forests and urban areas. predictive models rely on ground data for health. This requires the involvement of The take-away is that wildland fire validation, which is often a challenge in forest managers, hydrologists, wildfire impacts on water supply and water developing countries. Although higher scientists, public-health specialists and quality will continue to extend well spectral and temporal data resolutions are the public. There is also a need to quantify beyond forest boundaries and to a welcome development, scientists need water contamination coming from burnt directly affect the forest hydrologic better training in the use of these data to anthropogenic sources such as plastics, services of people living downstream. predict the effectiveness of nature-based gases and fabrics when builtup areas are Ultimately, a better understanding of

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Box 5 China’s “Grain-for-Green” programme: improving water quality through afforestation and forest restoration

Satellite imagery shows that China is becoming greener following years of afforestation and forest protection efforts. The aim of the Conversion of Cropland to Forest Programme (CCFP), or “Grain-for-Green”, the world’s largest payment scheme for ecosystem services, is to combat soil erosion and improve the rural environment. Afforestation (planting trees where no forest existed previously) is one of its core activities, financed through a public payment scheme that involves millions of rural households (Lü et al., 2012). Sediment monitoring in the Yangtze River and elsewhere shows evidence of reduced sediment loads following the start of the CCFP in 1999 and the Natural Forest Protection Programme in 1998, with a positive effect on drinking-water quality (Zhou et al., 2017; Mo, 2007). There are concerns, however, that afforestation with non-native tree species uses too much water and causes soil desiccation (Deng et al., 2016), potentially leading to lower water levels in, for example, the Yellow River, with severe consequences for downstream water supply. Additionally, forest planning in China has rarely considered prescribed burning as a management tool and instead favours fire suppression. There is a strong need to monitor and predict potential fire impacts on water services to ensure the cost-effectiveness of forest restoration efforts (Cao et al., 2011). © STACIE WOLNY, STANFORD© STACIE WOLNY, UNIVERSITY

Forest restoration in southern China’s Pearl River Basin has reduced erosion, leading to better water quality in rivers

regional fire impacts and interactions is ACKNOWLEDGEMENTS (ORISE) through an interagency agreement needed for a breakthrough in the devel- Dennis W. Hallema received support from between the United States Department opment of cost-effective strategies for the Forest Service Research Participation of Energy (DOE) and the USDA Forest managing fire and water. Program administered by the Oak Ridge Service. ORISE is managed by Oak Institute for Science and Education Ridge Associated Universities (ORAU)

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Nature-based solutions for water-related disasters

L. Spurrier, A. Van Breda, S. Martin, R. Bartlett and K. Newman © WWF-MADAGASCAR

Mangroves are crucial resources angrove forests are among the building materials and local subsistence for many of the world’s most world’s most valuable coastal use (Nagelkerken et al., 2008). vulnerable people, but more ecosystems, providing local Serving as a transition between marine research and coordination is Mcommunities with numerous services and and terrestrial environments, mangroves needed to inform decisions on their benefits. They function as nursery habitats can provide vulnerable people with protec- role in disaster risk reduction. for many animals, such as crab, prawn and tion against the impacts of climate change fish species, support local food webs, and (Munang et al., 2013) by attenuating wave Lauren Spurrier is Vice President, Oceans Conservation, World Wildlife Fund (WWF), create linkages with other ecosystems for energy and storm surges, buffering ris- Washington, DC, United States of America nutrient cycling and migratory pathways ing sea levels, stabilizing shorelines from Anita Van Breda is Senior Director, (Nagelkerken et al., 2008). Mangroves erosion, and contributing to general flood Environment and Disaster Management, WWF, Washington, DC, United States of America also support a vast array of culturally control (Vo et al., 2012). Mangroves pro- Shaun Martin is Senior Director, Climate and environmentally important species, vide even more ecosystem services when Change Adaptation and Resilience, WWF, including shorebirds, crocodiles, mana- coupled with coral reefs and seagrass beds. Washington, DC, United States of America Ryan Bartlett is Director, Climate Risk and tees, and even tigers in the Sundarbans Despite the many benefits, however, the Resilience, WWF, Washington, DC, United States (Danda et al., 2017). Millions of people global extent of mangroves has declined of America living along coasts benefit from mangroves Kate Newman is Vice President, Forest and Freshwater Public Sector Initiative, WWF, for aquaculture, agriculture, forestry, pro- Above: Community mangrove Washington, DC, United States of America tection against shoreline erosion, woodfuel, restoration in Madagascar

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by 67 percent in the last century. Roughly DRR in a changing climate. It recom- mangroves should feature in overall disas- 1 percent of mangrove cover is now being mends further research, collaboration ter risk management strategies. lost per year (FAO, 2007), driven by coastal and coordination among the humanitar- Traditional built infrastructure options development, aquaculture, resource use ian, land-use planning, conservation, for coastal defence are proving inadequate and, in some instances, climate change. climate-change adaptation, development, – and at times counterproductive – in deliv- Mangrove loss can increase the vulner- and disaster management sectors to enable ering risk-mitigation outcomes to life and ability of coastal communities and the risks better-informed decisions on the use of property. Hard defences such as sea walls, to which they are exposed (Blankespoor, mangroves for DRR. levees and bulkheads can provide a general Dasgupta and Lange, 2016). Continued sense of security because they are familiar, declines in mangrove area could lead to COASTAL PROTECTION FROM A well understood and often constructed dramatic losses of biodiversity, increased COMBINATION OF NATURAL AND following codified local regulations. For salt intrusion in coastal zones, and the BUILT INFRASTRUCTURE these reasons and others, hard infrastruc- siltation of coral reefs, ports and shipping Integrating mangroves in DRR is not an ture is often preferred over nature-based lanes, with consequent losses of income entirely new concept. Coastal managers and solutions like mangroves. Nevertheless, and livelihood options (FAO, 2007). scientists have long recognized the value of there are many disincentives for relying Mangroves are essential for reducing the mangroves and related coastal ecosystems, solely on built infrastructure. For example, vulnerability of many coastal communi- such as coral reefs and seagrass beds, in built infrastructure has high construction, ties to the impacts of climate change and mitigating the impacts of coastal hazards, operational and maintenance costs, and it increasingly intense and frequent extreme including storm surges and flooding from is strongest immediately after construc- weather events. Yet climate change itself cyclones and, to some extent, tsunamis. As tion and then weakens with age. Moreover, presents a significant threat to mangroves coastal “bioshields”, mangrove forests can hard infrastructure is built using specific that could undermine their value in reduc- attenuate wave energy and reduce vulner- parameters, and it might be difficult to ing this vulnerability (Algoni, 2015). To ability to storm surge inundation, although adapt it to rising sea levels or other changed maximize opportunities for disaster risk their effectiveness depends on a range of conditions. It can also cause coastal habi- reduction (DRR), conservationists and site-specific factors (Box 1). Variations in tat loss and have negative impacts on the disaster risk managers must pay careful coastal characteristics and the influence attention to the threats that are driving the of humans on mangrove systems affect rapid loss of mangroves globally and their the relative value of mangroves as coastal Mangroves in Sundarban Forest on the edge capacity to survive in a changing climate. defence mechanisms. Thus, it is impor- of the Bay of Bengal, Khulna Province, south Disaster risk managers must also con- tant to carefully review sites to determine coast of Bangladesh. These mangroves are battered by the sea, but they play an sider the current and future viability of the extent to which existing or restored important role in protecting the coast from the protective services of mangroves. For storms and erosion example, the implications of the combined impacts of sea-level rise, changing salin- ity, extreme weather events, economic development (e.g. aquaculture and fisher- ies) and infrastructure development (e.g. roads, dams and urbanization) should be understood to best determine how man- groves might contribute to risk reduction for people in long-term DRR planning. At the same time, conservationists must take urgent action to reduce threats to existing © NATUREPL.COM/TIM LAMAN/WWF © NATUREPL.COM/TIM mangroves and to enable mangrove tree species to migrate inland and to new areas as sea levels rise. Policymakers and land managers must understand the interaction of these factors at a landscape scale. This article presents the factors that should be considered when evaluating the value of mangrove ecosystems for

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Box 1 Planning considerations A comprehensive understanding of mangrove ecosystems is crucial for an agency’s (governmental or community-managed) capacity to plan the role of mangroves in DRR strategies. The duration and extent to which mangroves can provide protection depends on many factors, including – but not limited to – the following: • the characteristics of mangroves and the surrounding environment; • the physical and geological conditions of a site, such as forest floor shape, shoreline configuration and bathymetry; • the size of the ecosystem, vegetation density and stiffness (contributes to an understanding of frictional resistance), and the height of the mangrove forest (Sutton-Grier, Wowk and Bamford, 2015); and • the hydrologic functioning of the landscape (Radabaugh et al., 2019).

Characteristics of threats: • The spectral characteristics of the incident waves and the tidal stage at which a wave enters a forest (Blankespoor, Dasgupta and Lange, 2016) • The height of the storm wave and windspeed (Spalding et al., 2014) • The number and duration of extreme events (Spalding et al., 2014) • Mangrove resilience, recovery and regeneration following an extreme event • The type of hazard to which a community is exposed (e.g. storm, tsunami, erosion, sea-level rise) (Spalding et al., 2014) • The distance of human communities and infrastructure from the shoreline • The human response to the event (e.g. cutting poles for rebuilding, the placement of hard structures or barriers within a mangrove eco­ system, and the rebuilding of roads adjacent to the ecosystem). ecosystem services provided by nearby defence capacity and deliver a wide range impacts in the Lower Florida Keys and coastal ecosystems (Sutton-Grier, Wowk of co-benefits that contribute to the overall Ten Thousand Islands. It made several key and Bamford, 2015). economic, social and ecological resilience findings, including: Some of the limitations of built (“grey”) of coastal systems. • There was extensive canopy damage and natural (“green”) infrastructure can from high winds; the canopy cover be addressed by using a hybrid approach DISASTER IMPACTS ON increased from 40 percent to 60 per- combining grey and green coastal defence MANGROVES AND POST-EVENT cent within 2–4 months after the hurri- options in shoreline management, par- RECOVERY cane but recovery plateaued thereafter. ticularly in cyclone and tsunami-prone Effective DRR planning should consider • Deposits of mud and debris (which areas. According to a growing body of the impacts of extreme events on man- could include non-organic debris, research and experimentation globally, groves. The rate and extent of recovery can household items and furniture) from the combination of natural and built infra- vary widely depending on factors such as storms hamper regrowth by smoth- structure can both increase resilience and species type, sediment availability, tem- ering roots and soil and decreasing decrease costs. For example, mangrove perature, precipitation, storminess and oxygen exchange. Trees that initially projects in Viet Nam can be 3–5 times sea-level rise (Ward et al., 2016). Some survive a storm may die due to this cheaper (depending on water depth) than a extreme events may completely destroy smothering. breakwater for the same level of protection an area of mangroves, transforming it • A lack of water, or excess water, can (Narayan et al., 2016). Hybrid approaches into mudflats (Smith et al., 2009). Meta- kill mangroves. can enhance natural systems and their analysis of disaster research (Mukherjee • Forests with appropriate elevation, benefits. Newly restored mangroves, for et al., 2010) suggests that, despite many hydrology and a source of propagules example, can be weak while tree roots post-disaster assessments, few include a should recover naturally. take hold, and younger trees have a bet- comprehensive analysis of disaster impacts Understanding the impacts of extreme ter chance of surviving major storms and on mangroves and related ecosystems or events on coastal ecosystems like man- other stressors if protected by permeable combine natural, social, economic and risk groves, as in the above example after (temporary) engineered structures as they management analysis. As a result, there Hurricane Irma, and how they recover from mature (Sutton-Grier, Wowk and Bamford, is no clear understanding of how coastal such events, can provide a basis for deter- 2015). By ensuring that mangroves are systems collectively provide DRR services. mining future mangrove risk-reduction restored and maintained, coastal managers A recent report (Radabaugh et al., potential. The post-disaster monitoring and decision-makers can increase coastal 2019) documented post-Hurricane Irma and analysis of mangrove ecosystems can

Unasylva 251, Vol. 70, 2019/1 70 © ADAM OSWELL/WWF-GREATER MEKONG A mangrove tree in the Mekong delta, Viet Nam, with its roots extending 5m up the trunk INCREASED ATMOSPHERIC CO also inform decisions on the suitability ² and value of assisting regeneration pro- cesses and provide insights useful for the development of future DRR objectives and activities. INCREASE IN TEMPERATURE The case of Cyclone Jokwe in Mozambique in 2008 illustrates how other post-disaster challenges are often ALTERED not considered. At the request of CARE, INCREASED SEA-LEVEL OCEAN RISE CURRENTS PRECIPITATION WWF conducted a rapid environmental STORMINESS REGIME assessment in the immediate aftermath of the cyclone to examine the potential for CARE’s reconstruction strategy to include environmentally responsible approaches

PLANT EROSION SEDIMENT MANGROVE SALINITY PRODUCTIVITY SUPPLY DROWNING 1 Main factors and pathways affecting mangrove systems under climate change Source: Ward et al. (2016), used here under a CC BY 4.0 licence.

Unasylva 251, Vol. 70, 2019/1 71 © ANTONIO BUSIELLO/WWF-US © ANTONIO

The development of a tourism project is destroying mangroves at Harvest Cayes, levels; 2) increasing atmospheric carbon 2016) estimated the loss of protective Placencia, Belize, Central America dioxide; 3) warmer air and water tempera- services from mangroves in 46 countries tures; 4) changing ocean currents; and 5) under a future scenario of a 1 m rise in sea and to support joint CARE–WWF natu- the increasing variability and intensity of level and a 10 percent increase in storm ral resource management activities. The rainfall (see Figure 1 on p. 68). Of these, intensification. It found that, assuming subsequent report showed that extraction sea-level rise is the most significant chal- no loss of mangroves to human action pressure on mangrove systems can increase lenge because it increases soil salinity and or sea-level rise, coastal flooding would following a disaster: communities began thus drives higher rates of seedling mortal- increase by only 2 percent globally. Results rebuilding their homes immediately using ity (Ward et al., 2016). How and whether were dramatically different and varied mangrove timber, driving up the rate of mangroves survive in a future of increasing significantly by country, however, when the mangrove consumption more than 14-fold climatic change and sea-level rise will be loss of mangroves due to the 1 m rise was compared with non-emergency times, determined by four factors: 1) whether factored in. Indonesia, for example, would potentially reducing the protective role of they can migrate inland (depending on the lose about 17 percent of its mangroves to the mangrove ecosystem. DRR managers topography or infrastructure in their way); sea-level rise, thus causing the loss of should factor such issues into planning 2) tidal range location and geomorphic coastal protection in those areas. Mexico, and management. setting (related to the type of mangrove on the other hand, was estimated to lose community); 3) continued supplies of sedi- all its existing mangroves, suggesting that MANGROVE VULNERABILITIES DUE ment; and 4) whether mangrove migration investments in mangroves for coastal pro- TO CLIMATE CHANGE inland can outpace the rate of sea-level rise tection in that country might not deliver The conservation and disaster risk man- (Blankespoor, Dasgupta and Lange, 2016; expected benefits in the mid to long term. agement communities often disregard the Ward et al., 2016). The study by Blankespoor, Dasgupta vulnerability of mangroves to climate Given the vulnerability of mangroves to and Lange (2016) has several limitations, change in planning substantial investments sea-level rise in some locations, appropri- and it could have over- or underestimated in mangrove protection and restoration ate site selection is crucial for ensuring the the future protective value of mangrove (Sutton-Grier, Wowk and Bamford, 2015). continued delivery of coastal protection ecosystems. Nevertheless, its findings Mangroves are directly affected by climate services from mangroves. A World Bank demonstrate an often-overlooked point: change through five vectors: 1) rising sea study (Blankespoor, Dasgupta and Lange, although mangroves will be crucial

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Mozambique

Mangrove cover reduced byBox 20,893 2 ha between 1996 and 2016 in Mozambique representing 6.5% of 1996 mangrove cover (Figure Ecosystem5). There are 18 linkages: rivers with a Vol/Len>100 mangroves with mangrove and coverrivers within the 10x AOI exceeding 10 ha in either 1996 or 2016. Eleven of these rivers are free-flowing, two have good connectivity, and 5 are not free-flowing. Two of the 18 rivers are river order 3, eleven WWF identified linkages between rivers areand order 4, and five are river order 5. The greatest loss of mangroves near river-ocean outlets occurred by Zambezi (-13042 ha, -3.8%, river #13 in Figure 5). The greatest gain in mangrove area occurred by Pungue (river #14 in Figure 5, a 201 ha gain in area, mangroves at the national and global scale inrepresenting a 9.4% of 1996 mangrove area). River–mangrove connectivity in Mozambique recent project (Maynard et al., 2019) by combining two novel, state-of-the-art global datasets on rivers (Grill et al., 2019) and mangrove extent in 1996– 2016 (Bunting et al., 2018). Rivers were catego- rized as “free-flowing” (very few human impacts), “good connectivity” (slight human impacts), or “not free-flowing” (moderate to severe human impacts). The project indicated that sediment trap- ping by dams was a major driver of mangrove loss adjacent to rivers, reducing the DRR potential of these forests. Further analysis is ongoing.1 Here we present the results from Mozambique. Mozambique experienced a national decline in mangrove cover from 319 445 ha in 1996 to 298 552 ha in 2016, equivalent to an overall loss of 7 percent. Mangroves adjacent to rivers were lost at a lower rate (3 percent), from 55 853 ha in 1996 to 54 389 ha in 2016. Of 18 selected rivers in Mozambique (Figure 2), 11 were categorized as “free-flowing” and two as having “good con- nectivity”. Five rivers, however, were categorized as “not free-flowing”, with significant human impacts. All five of these rivers are in southern Mozambique and have experienced substantial losses of mangrove area: for example, the Zambezi (River 13 in Figure 2) lost 1 304 ha of mangroves between 1996 and 2016. With increasing energy demand, Mozambique is looking to expand river hydroelectric power generation, with four new dams planned nationally for the Zambezi (Zarfl et al., 2015). Moreover, an additional 12 dams are planned upstream, where the Zambezi and Figure 5. Country map summary for Mozambique; mangrove cover change between 1996 and 2016 its tributaries flow through Malawi, the United Source: Maynard et al. (2019). nearNotes: river All -riversocean with outlets. a cross-sectional area greater than 100 m² at the river–ocean outlet Republic of Tanzania, Zambia and Zimbabwe (this can be visualized as a river 50 m wide and 2 m deep) are numbered. River order reflects 19 (Zarflet al., 2015). These dams are likely to further how a river fits within a river network, with the longest continuous river from source to ocean exacerbate mangrove loss in the Zambezi delta. identified as order 1. Tributaries off this backbone are labelled as order 2 along their longest length from source to backbone; further tributaries from these order 2 river segments are labelled order 3, 4, etc., to a maximum of 7 river orders.

in many areas for protecting coastal MANGROVE VULNERABILITIES DUE easily be undermined by external threats assets and people from increasingly TO UPSTREAM DEVELOPMENT that occur beyond their “boundaries”. This extreme storms and flooding, advocates Mangrove ecosystems are highly connected is especially important at river–ocean should be careful not to oversell the to adjacent landscapes and seascapes, boundaries, where processes occurring benefits, especially in areas with low which affect their health and integrity far upstream in terrestrial watersheds can potential for inland mangrove migration (Ervin et al., 2010). Attempts to conserve have large impacts on coastal ecosystems. (such as in Mexico). mangrove forests locally, therefore, can For example, 31 percent of sediment that

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should be carried into Asian deltas and ecosystems but should take a carefully • As mangroves migrate due to a chang- which would help replenish coastlines is designed, hybrid approach that includes ing climate, they may no longer pro- prevented by dams (Syvitski et al., 2005), appropriate built infrastructure, as well vide the same protective functions to with major rivers in Pakistan, Thailand as early-warning systems and community communities relying on them. and Viet Nam experiencing 75–95 percent education (Blankespoor, Dasgupta and • Adaptive frameworks and decision- declines in coastal sediment deposition Lange, 2016). support tools that enable managers to (Gupta, Kao and Dai, 2012). Such upstream It is especially important to factor integrate and continuously update pro- sediment-trapping leads to increased in climate change (including sea-level jections of climate-change risk, land coastal erosion and causes mangrove for- rise) because it may cause mangroves to use and human population growth can est loss, with examples observed on the migrate and thereby reduce their protec- increase the effectiveness of natural Mexican Pacific coast (Ezcurraet al., 2019) tive function in a particular area. Adaptive infrastructure, including mangroves. and in the Mekong delta (Li et al., 2017) frameworks and decision-support tools • Although the value of mangroves in and Mozambique (Box 2). Yet coastal can increase the effectiveness of natural providing DRR services are well docu- DRR efforts and upstream river man- infrastructure, including mangroves, by mented, they are rarely considered in agement efforts are routinely disjointed, enabling managers to integrate and con- planning and development. Neverthe- with mangrove forest jurisdiction often tinually update the risks posed by climate less, in some circumstances, assertions slipping through the cracks between ter- change as well as changes in land use and that mangroves reduce disaster risk restrially focused government forestry and human populations (Powell et al., 2019). are overly simplistic, do not present environment agencies and marine- and In summary: the full suite of conditions and issues fisheries-focused departments. Without • There is a growing body of evidence that need to be considered to evaluate holistic management approaches, upstream that mangroves provide effective mangrove protective attributes (i.e. management decisions could undermine protection for vulnerable communi- geomorphology and forest intact- the capacity of mangroves to provide DRR. ties from hazards such as tropical ness), and can therefore potentially storms and tsunamis and from chronic increase risk by providing a false sense CONCLUSION AND stressors such as sea-level rise and of security. u RECOMMENDATIONS coastal erosion. Although the value of mangroves in pro- • Disaster risk managers can improve viding DRR services is well-documented outcomes in the use of mangroves for (albeit with a need for more integrated DRR by carefully considering a range and multidisciplinary post-disaster stud- of factors in risk reduction analysis, ies), they are rarely considered in planning planning and management. They References and development. Even when the role of should consider the viability of cur- mangroves in DRR is acknowledged, the rent – and potential for future – protec- Algoni, D.M. 2015. The impact of climate full suite of conditions and issues that tive mangrove ecosystem services in change on mangrove forests. Current need to be considered to evaluate protec- the context of combined climate and Climate Change Reports, 1(1): 30–39. tive attributes (e.g. geomorphology and development impacts over time to bet- Blankespoor, B., Dasgupta, S. & Lange, G.M. forest intactness) may be downplayed ter understand how well and to what 2016. Mangroves as protection from storm and oversimplified. Along with an over­ extent mangroves might help reduce surges in a changing climate. Washington, reliance on hard coastal defence systems, risks. Policymakers and managers DC, World Bank. the lack of fully integrated assessment should understand the interaction of Bunting, P., Rosenqvist, A., Lucas, R., Rebelo, can inadvertently increase risk by pro- these factors at a landscape scale. L.M., Hilarides, L., Thomas, N., Hardy, viding a false sense of security among • Integrated, multidisciplinary post- A., Itoh, T., Shimada, M. & Finlayson, C. coastal communities (Park et al., 2013). disaster studies can increase under- 2018. The global mangrove watch – a new The consideration of the viability of cur- standing of the DRR efficacy of 2010 global baseline of mangrove extent. rent – and potential for future – protective mangroves. Remote Sensing, 10(10): 1669. mangrove ecosystem services, in the face • It is important to consider how long Danda, A.A., Joshi, A., Ghosh, A.K. & of the combined impacts of change over it will take for mangroves affected by Saha, R. 2017. State of the art report on time, can aid policymakers and managers extreme events to recover and thereby biodiversity in Indian Sundarbans. New at a landscape scale. Coastal protection provide their protective services. This Delhi, World Wide Fund for Nature-India. plans should not rely solely on the pro- should be factored into recovery and Ervin, J., Mulongoy, K.J., Lawrence, K., tection benefits of mangroves and related DRR planning. Game, E., Sheppard, D., Bridgewater, P.,

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FAO FORESTRY

FRA2020 Global Remote Sensing Survey The FAO Forestry team responsible for the collection of forestry data from countries and the compilation of the 2020 Global Forest Resources Assessment (FRA2020) has been conducting training workshops. The aim of the workshops is to introduce country experts – who will provide FAO with revised data for FRA2020 – to new methods for collecting, storing and monitoring information using satellite imagery and to new tools designed to improve image processing and interpretation. The workshops will help develop national expert capacities in the production of accurate and comparable data following an internation-

© FAO ally agreed methodology and classification. Dignitaries gather on stage at the opening of The training sessions and the improved data collection are designed Asia-Pacific Forestry Week 2019 to assist in the upcoming FRA2020 Global Remote Sensing Survey, which will create a global dataset for assessing forest area, and The challenges facing forests in the Asia-Pacific forest-area change, at the regional and global levels. region Conducted by the FAO Forestry Department with the financial The 28th session of the Asia-Pacific Forestry Commission (APFC) support of the European Commission, the Global Remote Sensing was held on 17–21 June 2019 in Incheon, Republic of Korea, at the Survey aims to complement FRA2020 by providing a comprehensive invitation of the Government of the Republic of Korea. Delegates from overview of global forest resources. It is also intended to empower 22 member countries and 4 United Nations organizations participated national experts through participatory and collaborative approaches in the session, along with observers and representatives from 21 to develop national capacities in remote sensing assessment. regional and international intergovernmental and non-governmental The Global Remote Sensing Survey will use the open-source organizations. software Collect Earth Online, one of FAO’s Open Foris set of tools In addition to administrative matters, the APFC considered the developed in recent years by the National Aeronautics and Space following agenda items: the session’s theme of “forests for peace Administration (United States of America) and FAO with Google’s and well-being”; forest and landscape restoration; community forests, support. trade and markets; the impacts of technological advances on forests Global Remote Sensing Survey workshops have been held to date and forestry; FAO’s work on biodiversity; progress in implementing in Argentina, Brazil, China, the Democratic Republic of the Congo, activities in the region supported by the APFC and FAO; the third India, Madagascar, Paraguay, the Russian Federation and Thailand. Asia-Pacific Forest Sector Outlook Study (see “Forest Futures” on p. 78); forests and climate change; the state of forestry in Asia and More information: www.fao.org/forest-resources-assessment the Pacific; preparations for the 25th session of the Committee on Forestry and the XV World Forestry Congress; reports and recommendations from the 2019 Asia-Pacific Forestry Week (see below); global processes; and implementation of the United Nations Strategic Plan for Forests and collaboration with the United Nations Forum on Forests. T h e 2 019 A s i a - Pa c i fi c Fo r e s t r y We e k , h e l d i n I n c h e o n c o n c u r r e n t l y with the 28th session of the APFC, attracted about 2 000 participants from government, civil society, research, academia and the private sector. A total of 82 partner events – workshops, seminars and discussion forums – were convened over the week, generating rich debate and discussion on a wide range of pressing issues for forests in the Asia-Pacific region. Asia-Pacific Forestry Week coincides with sessions of the APFC to enable dialogue and feedback with the APFC member states and other forest stakeholders. The event in Incheon was hosted by FAO and the Korea Forest Service with the support of Incheon Metropolitan City and 18 institutions acting as stream leaders.

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WORLD OF FORESTRY ©FAO/LUIS TATO ©FAO/LUIS

Beneficiaries of an FAO programme on conservation Two new United Nations "decades" agriculture, Lucy Kathegu Kigunda and Gervasio Kigunda, pose on their family farm near Meru, Meru County, Kenya. FAO and United Nations partner agencies have launched two United Family farming is the focus of a United Nations “decade” Nations “decades” that will involve considerable contributions by in 2019–2028 FAO – and a significant forestry component – in their implementation: the United Nations Decade of Family Farming (2019–2028), and the approach is to strengthen the efforts of producer organizations to United Nations Decade on Ecosystem Restoration (2021–2030). sustain and improve the livelihoods of rural and forest communities, The United Nations Decade of Family Farming (2019–2028) was ensure fair and equitable access to markets, and encourage the proclaimed in December 2017 as a way of enabling family farming to inclusion of women as equal partners with men by empowering transform food systems and play an optimal role in achieving the 2030 them with the same rights and level of participation in community Agenda for Sustainable Development. FAO and the International Fund decision-making. for Agricultural Development launched the decade in Rome, Italy, on The United Nations General Assembly officially declared the 29 May 2019. A global action plan was also presented (see “United United Nations Decade on Ecosystem Restoration 2021–2030 on Nations Decade of Family Farming” on p. 79) to provide guidance on 1 March 2019. Its purpose is to coordinate the restoration of degraded the steps that need to be taken to achieve the decade’s goal and to ecosystems on a massive scale worldwide to fight the negative boost support for family farmers, especially in developing countries. consequences of climate change, especially regarding water supply The forestry component of the United Nations Decade of Family and biodiversity, and to increase food security. Farming is apparent through the work of the Forest and Farm Facility, It is estimated that ecosystem degradation negatively affects the a mechanism supported by FAO and partners. The Facility’s main well-being of more than 3 billion people and costs about 10 percent of

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annual gross product in the loss of ecosystem services. Food systems Global Landscapes Forum 2019 and agriculture, the supply of freshwater, protection against hazards Organized alongside the Bonn Climate Change Conference under and the provision of habitat for pollinators and wildlife are among the United Nations Framework Convention on Climate Change, the ecosystem services that are declining most rapidly. Ecosystem and building on the momentum on indigenous peoples’ rights built restoration, on the other hand, can generate trillions of dollars in at the 18th Session of the United Nations Permanent Forum on ecosystem services and remove large quantities of greenhouse Indigenous Issues in New York on 13–22 April 2019, the Global gases from the atmosphere. Landscapes Forum (GLF) held in Bonn, Germany, on 23 June 2019 UN Environment and FAO will lead the implementation of the Decade focused on the rights of indigenous peoples and local communities on Ecosystem Restoration, in collaboration with partners, with the aim and specifically on a rights-based approach to the restoration of of accelerating existing global restoration goals, such as the Bonn landscapes and forests. Challenge, the aim of which is to restore 350 million ha of degraded One of the main items on the agenda was the GLF’s contribution to ecosystems by 2030. the shaping of the United Nations Decade on Ecosystem Restoration. Among the regional initiatives conducive to that aim are Initiative Participants heard that about 370 million indigenous peoples in 20x20 in Latin America, which aims to restore 20 million ha of 87 countries worldwide manage or have tenure rights to more than degraded land by 2020, and the AFR100 African Forest Landscape 38 million km2, and they represent a powerful force for protection Restoration Initiative, which aims to bring 100 million ha of degraded against climate change. When their rights are recognized and land under restoration by 2030. enforced, indigenous peoples are effective managers of their lands, Mette Wilkie, the Director of the Forestry Policy and Resources which store vast quantities of carbon and provide habitat for a large Division at FAO, drew attention to the Action Against Desertification proportion of the world’s biodiversity. The GLF heard that it is impor- (AAD) programme, a powerful instrument implemented by FAO and tant for the international community to recognize that the relationships partners funded by the European Union, the aim of which is to promote of indigenous peoples with the natural world are crucial not only for sustainable land management and restore drylands and degraded the conservation of their own lands but also for the well-being of all. lands in Africa, the Caribbean and the Pacific. Also at GLF 2019, the Rights and Resources Initiative and the “Greening the world’s drylands is indeed possible and brings with Indigenous Peoples Major Group for Sustainable Development it a wealth of associated benefits, from reduction of poverty and presented a first draft of a “gold standard” for rights. The aim of hunger to mitigation of climate change and reduced risks of conflict,” the standard is to define the principles of secure and proper rights said Ms Wilkie. that organizations, institutions, governments and the private sector should apply in the implementation of landscape-based projects, businesses, initiatives and the law.

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BOOKS

0.36 cm spine for 72 pg on 90g paper 0.66 cm spine for 112pg on 90g paper 181 182 182 181 FAO FORESTRY PAPER FAO FORESTRY PAPER

Climate change Climate change Guide to the classical for forest policy-makers for forest policy-makers biological control of Guide to the classical biological An approach for integrating An approach for integrating climate change into national insect pests in planted climate change into national forest control of insect pests in forest policy in support of sustainable forest management and natural forests Guide to the classical biological control of insect pests in planted and natural forests policy in support of sustainable planted and natural forests forest management Version 2.0 Version 2.0 Insect pests damage millions of hectares of forest worldwide each year. Moreover, the extent of such damage is increasing as international trade grows, facilitating the spread of insect pests, and as the The critical role of forests in climate change Climate change for forest policy-makers impacts of climate change become more evident. mitigation and adaptation is now widely recognized. Classical biological control is a well-tried, Forests contribute significantly to climate change cost-effective approach to the management of mitigation through their carbon sink and carbon invasive forest pests. It involves the importing of storage functions. They play an essential role in “natural enemies” of non-native pests from their reducing vulnerabilities and enhancing adaptation countries of origin with the aim of establishing of people and ecosystems to climate change and permanent, self-sustaining populations capable of climate variability, the negative impacts of which sustainably reducing pest populations below are becoming increasingly evident in many parts of damaging levels. the world. A great deal of knowledge on classical biological In many countries climate change issues have not control has been accumulated worldwide in the last been fully addressed in national forest policies, few decades. This publication, which was written by forestry mitigation and adaptation needs at national a team of experts, distils that information in a clear, level have not been thoroughly considered in concise guide aimed at helping forest-health national climate change strategies, and cross-sectoral practitioners and forest managers – especially in dimensions of climate change impacts and response developing countries – to implement successful measures have not been fully appreciated. This classical biological control programmes. It provides publication seeks to provide a practical approach to general theory and practical guidelines, explains the the process of integrating climate change into “why” and “how” of classical biological control in national forest programmes. The aim is to assist forestry, and addresses the potential risks associated senior officials in government administrations and with such programmes. It features 11 case studies of the representatives of other stakeholders, including successful efforts worldwide to implement classical civil society organizations and the private sector, biological control. prepare the forest sector for the challenges and opportunities posed by climate change. This document complements a set of guidelines prepared by FAO in 2013 to support forest managers incorporate climate change considerations into forest management plans and practices.

ISBN 978-92-5-131335-0 ISSN 0258-6150

ISSN 0258-6150 ISBN 978-92-5-131094-6 ISSN 0258-6150 ISSN 0258-6150

FAO FAO FORESTRY FORESTRY FAO PAPER FAO PAPER 978 9251 313350 9789251 310946 CA3677EN/1/03.19 CA2309EN/1/11.18 182 181

Managing invasive forest pests with classical The role of forests in climate-change mitigation

biological control Climate change for forest policy-makers: an approach for integrating climate change Guide to the classical biological control of insect pests in planted and natural into national forest policy in support of sustainable forest management. Version 2.0. forests. FAO Forestry Paper No. 182. M. Kenis, B.P. Hurley, F. Colombari, FAO Forestry Paper No. 181. 2018. Rome, FAO. ISBN 978-92-5-131094-6. S. Lawson, J. Sun, C. Wilcken, R. Weeks, & S. Sathyapala. 2019. Rome, FAO. Forests contribute significantly to climate-change mitigation through ISBN 978‑92‑5‑131335‑0. their carbon sink and carbon storage functions. They play essential Insect pests damage millions of hectares of forest each year roles in reducing vulnerabilities and enhancing the adaptation of worldwide. Moreover, the extent of such damage is increasing as people and ecosystems to climate change and climate variability, international trade grows (facilitating the spread of insect pests) and the negative impacts of which are becoming increasingly evident in as the impacts of climate change become more evident. many parts of the world. Classical biological control is a well-tried, cost-effective approach In many countries, however, climate change is not being fully to the management of invasive forest pests. It involves the importing addressed in national forest policies. Moreover, forest-related of “natural enemies” of non-native pests from their countries of origin climate-change mitigation and adaptation needs have not been with the aim of establishing permanent, self-sustaining populations thoroughly considered in national climate-change strategies, and capable of sustainably reducing pest populations below damaging the cross-sectoral dimensions of climate-change impacts and levels. A great deal of knowledge on classical biological control has responses are underappreciated. This publication provides a been accumulated worldwide in the last few decades. practical approach to the process of integrating climate change into This publication, which was written by a team of experts, distils national forest programmes. The aim is to assist senior officials in such knowledge in a clear, concise guide aimed at helping forest- government administrations and the representatives of other stake- health practitioners and forest managers – especially in developing holders, including civil-society organizations and the private sector, countries – to implement successful classical biological control to prepare the forest sector for the challenges and opportunities programmes. It provides general theory and practical guidelines, posed by climate change. explains the “why” and “how” of classical biological control in This document complements a set of guidelines prepared by FAO forestry, and addresses the potential risks associated with such in 2013 to support forest managers in incorporating climate-change programmes. It features 11 case studies of successful efforts to considerations into forest management plans and practices. implement classical biological control. Available online: www.fao.org/3/CA2309EN/ca2309en.pdf Available online: www.fao.org/3/ca3677en/CA3677EN.pdf

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0.66 cm spine for 132 pg on 90g paper 180 180 FAO FORESTRY PAPER

Making forest concessions in the tropics work to Making forest concessions in FOREST FUTURES achieve the 2030 Agenda: Making forest concessions in the tropics work to achieve 2030 Agenda: Voluntary Guidelines the tropics work to achieve the Sustainable pathways for forests, landscapes Voluntary Guidelines 2030 Agenda: Voluntary Guidelines and people in the Asia-Pacific region

Sustainable wood products and their value chains can play a fundamental role in achieving the objectives stated in the 2030 Agenda and the Paris Agreement, delivering a wide range of benefits to populations in remote forest areas as well as to local, regional and global society. Generation of income and employment, disaster risk reduction, and reduction of the material and carbon footprint of the planet are some of the direct contributions sustainable forest products can provide to the SDGs and the climate change commitments. Furthermore, sustainable management of natural forests reduces forest degradation and forest production can increase the opportunity cost for deforestation, while generating revenues for conservation strategies.

These Voluntary Guidelines for forest concessions focus on concessions as a forest policy instrument for the delivery of sustainable forest management in the tropics, building on lessons learned from success and failures in implementing forest concession. The guidelines offer a practical participatory management approach to support forest concession regimes to be reliable sources of sustainable wood and non-wood forest products and contribute to realizing the full contribution of forestry to the 2030 Agenda.

With the financial support of

ISBN 978-92-5-130547-8 ISSN 0251-6150 ISSN 0258-6150 FAO FORESTRY FAO PAPER 978 9251 305478 Asia-Pacific Forest Sector Outlook Study III I9487EN/1/05.18 180

Concessions for sustainable wood production in The future of forests in Asia and the Pacific

the tropics Forest futures: sustainable pathways for forests, landscapes and people in the Asia- Making forest concessions in the tropics work to achieve the 2030 Agenda: Pacific region. Asia-Pacific Forest Sector Outlook Study III. 2019. Bangkok, FAO. Voluntary guidelines. FAO Forestry Paper No. 180. Y.T. Tegegne, J. Van Brusselen, ISBN 978-92-5-131457-9. M. Cramm, T. Linhares-Juvenal, P. Pacheco, C. Sabogal & D. Tuomasjukka. 2018. Forests and landscapes in the Asia-Pacific region are under Rome, FAO and the European Forest Institute. ISBN 978-92-5-130547-8. increasing pressure from economic development, climate change, Sustainable wood products and their value chains can play demographic shifts, conflicts over tenure and land use, and other fundamental roles in achieving the objectives of the 2030 Agenda stressors. This publication, the third Asia-Pacific Forest Sector for Sustainable Development and the Paris Agreement on climate Outlook Study, presents scenarios and a strategic analysis to help change, delivering a wide range of benefits to communities in policymakers and other actors understand the implications of these remote forest areas as well as to local, regional and global societies. stressors for forests and forestry in the Asia-Pacific region and how Sustainable forest products can make direct contributions to the best to address the challenges ahead. Sustainable Development Goals, such as by providing income The product of outstanding collaboration among institutions, and employment, abating the risk of disasters, and reducing networks and more than 800 individuals across the region, the environmental footprints. Moreover, the sustainable management of study examines the drivers of change in the region’s forest sector natural forests reduces forest degradation, while sustainable forest and explores three scenarios – business-as-usual, aspirational and production can increase the opportunity costs of deforestation and disruptive – to 2030 and 2050. It shows that “more of the same” will generate revenues for conservation strategies. likely lead to highly negative outcomes over both time horizons. These voluntary guidelines for forest concessions focus on On the other hand, the adoption of landscape approaches and concessions as a policy instrument for the delivery of sustainable other key measures could help realize the enormous potential of forest management in the tropics, building on lessons learned from forests – with their capacity to simultaneously perform multiple successes and failures in implementing forest concessions. The economic, social and environmental functions – to help achieve guidelines offer a practical participatory management approach to development goals in and beyond the forest sector. A key message ensuring that forest concession regimes act as reliable sources of of the report is that the region must respond now to ensure the sustainable wood and non-wood forest products and contribute to resilience of forests, landscapes and communities and thereby avoid realizing the full contributions of forestry to the 2030 Agenda for catastrophic outcomes. The report sets out seven “robust actions” Sustainable Development. for operationalizing this response.

Available online: www.fao.org/3/I9487EN/i9487en.pdf Available online: www.fao.org/3/ca4627en/ca4627en.pdf

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UNITED NATIONS DECADE OF FAMILY FARMING 2019-2028 Global Action Plan

Joint Secretariat of the UN Decade of Family Farming

Food and Agriculture Organization of the United Nations (FAO) Viale delle Terme di Caracalla 00153 Rome, Italy

[email protected] www.fao.org/family-farming-decade #FamilyFarming UNITED NATIONS DECADE OF FAMILY FARMING 2019-2028 ISBN 978-92-5-131472-2 Global Action Plan

978 9251 314722 1 CA4672EN/1/05.19

Strengthening the contributions of family farming to Improving the governance of forest tenure

food systems Assessing the governance of tenure for improving forests and livelihoods: a tool United Nations Decade of Family Farming 2019-2028: Global Action Plan. to support the implementation of the Voluntary Guidelines on the Responsible 2019. Rome, FAO and International Fund for Agricultural Development (IFAD). Governance of Tenure. FAO Forestry Working Paper No. 13. 2019. Rome, FAO. ISBN 978‑92-5-131472-2. ISBN 978-92-5-131553-8. By placing family farming at the centre of the international agenda Governments around the world have been attempting for many for a period of ten years, the United Nations Decade of Family years to strengthen and give formal recognition to customary tenure. Farming (2019–2028) provides an unprecedented opportunity to In addition, forestry departments have introduced various types of achieve positive change in food systems globally. Family farmers participatory arrangements recognizing certain resource-use rights of have proven their capacity to develop new strategies and provide local communities with the purpose of improving forest governance innovative responses to emerging economic, social and environmental and reducing poverty. challenges. They don’t just produce food: they simultaneously perform This assessment tool was developed to better understand the environmental, social and cultural functions, act as custodians of strengths and limitations of such forest-tenure reforms. It uses the biodiversity, and help preserve landscapes and maintain community internationally endorsed Voluntary Guidelines on the Responsible and cultural heritage. Family farmers also have the knowledge to Governance of Tenure of Land, Fisheries and Forests as its basis. produce nutritious and culturally appropriate food as part of local Although the tool enables the assessment of all forms of tenure traditions. arrangements, it can be particularly helpful for assessing those that The Global Action Plan of the United Nations Decade of Family recognize customary tenure in forestry through participatory for- Farming (2019–2028) represents the tangible result of an exten- estry initiatives such as collaborative forestry, community forestry sive and inclusive global consultation process involving diverse and smallholder forestry. The tool also enables the identification partners worldwide. The aim is to mobilize coordinated actions to and assessment of customary-tenure systems not recognized in help family farmers overcome the challenges they face, increase statutory law. their investment capacity, and thereby obtain the benefits of their As experienced in several test countries, the findings and recom- contributions in transforming societies and putting in place long- mendations emerging from the assessment of tenure arrangements term, sustainable solutions. can provide valuable insights into the strengths and limitations of existing arrangements and reforms and help generate ideas for Available online: www.fao.org/3/ca4672en/ca4672en.pdf improving their performance in forest governance, strengthening local livelihoods and contributing to the Sustainable Development Goals.

Available online: www.fao.org/3/ca5039en/CA5039EN.pdf

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Valuing forest ecosystem services A training manual for planners and project developers

FORESTRY WORKING PAPER 11

Assessing the benefits of community forestry How to correctly estimate forest ecosystem services

A framework to assess the extent and effectiveness of community-based forestry. Valuing forest ecosystem services: a training manual for planners and project FAO Forestry Working Paper No. 12. 2019. Rome, FAO. ISBN 978-92-5-131547-7. developers. FAO Forestry Working Paper No. 11. M. Masiero, D. Pettenella, There has been significant expansion in the area under community- M. Boscolo, S.K. Barua, I. Animon & J.R. Matta. 2019. Rome, FAO. ISBN 978-92- based forestry (CBF) in the last four decades, involving a broad array 5-131215-5. of initiatives that favour people’s participation in forestry. The failure to appropriately consider the full economic value This aim of this assessment framework is to help in generating of ecosystem services in decision-making contributes to the insights into the successes and shortcomings of CBF at the country continued degradation and loss of ecosystems and biodiversity. level. The framework can also provide a means for determining Most ecosystem services are considered public goods and tend and tracking the extent and effectiveness of the broad spectrum to be overexploited by society. Recognizing, demonstrating and of CBF initiatives. capturing the value of ecosystem services, on the other hand, can Well-performing CBF has the potential to rapidly restore forests help in setting policy directions for ecosystem management and in ecological terms and scale up sustainable forest management conservation and thus in increasing the provision of ecosystem to the national level while improving livelihoods for many millions of services and their contributions to human well-being. marginalized people worldwide. In so doing, CBF has the potential The aim of this manual is to increase understanding of eco­ to contribute significantly to the Sustainable Development Goals. system services and their valuation. The target audience comprises government officers in planning units and field-level officers and prac- Available online: www.fao.org/3/ca4987en/CA4987EN.pdf titioners in key government departments in Bangladesh responsible for project development, including the Ministry of Environment and Forests and its agencies. Most of the examples and case studies presented herein, therefore, are tailored to the Bangladeshi con- text, but the general concepts, approaches and methods can be applied to a broad spectrum of situations. This manual focuses on valuing forest-related ecosystem services, including those provided by trees outside forests. It is expected to improve valuation efforts and help ensure the better use of such values in policymaking and decision-making. Among other things, the manual explores the basics of financial mathematics (e.g. the time value of money; discounting; cost–benefit analysis; and profitability and risk indicators); the main methods of economic valuation; examples of the valuation of selected eco­system services; and inputs for considering values in decision-making.

Available online: www.fao.org/3/ca2886en/CA2886EN.pdf

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BOOKS 8 Agroforestry and tenure and Agroforestry

Agroforestry and tenure State of Mediterranean Forests 2018

For more information, please contact:

Forestry Department

E-mail: [email protected] ISBN 978-92-5-131467-8 Web address: www.fao.org/forestry/en FORESTRY Food and Agriculture Organization of the United Nations WORKING 9 789251 314678 Viale delle Terme di Caracalla FAO PAPER CA4662EN/1/05.19 00153 Rome, Italy 8

Addressing tenure-related challenges in Climate change – opportunities and risks for agroforestry Mediterranean forests

Agroforestry and tenure. FAO Forestry Working Paper No. 8. S. Borelli, E. Simelton, State of Mediterranean forests 2018. 2018. Rome and Marseille, France, FAO and S. Aggarwal, A. Olivier, M. Conigliaro, A. Hillbrand, D. Garant & H. Desmyttere. Plan Bleu. ISBN 978-92-5-131047-2 (FAO). 2019. Rome, FAO and World Agroforestry (ICRAF). ISBN 978-92-5-131467-8. The Mediterranean region has more than 25 million ha of forests Agroforestry is gaining new ground in the quest for climate-smart and about 50 million ha of other wooded lands. They make vital agricultural practices due to its potential to sequester carbon and contributions to rural development, poverty alleviation and food mitigate climate change while increasing the socio-economic and security and to the agriculture, water, tourism and energy sectors. environmental sustainability of rural development. Changes in climate, societies and lifestyles in the Mediterranean, Yet agroforestry continues to face challenges, such as unfavour- however, could have serious negative consequences for forests. able policy incentives, legal constraints, and poor coordination Both to compensate for the lack of data on Mediterranean for- among sectors. In particular, many agroforestry researchers and ests and to provide a sound basis for their future management, the practitioners have identified insecure land and resource tenure as Committee on Mediterranean Forestry Questions-Silva Mediterranea a major obstacle to the promotion of this practice. requested FAO, in collaboration with other institutions, to prepare This publication reviews the main tenure-related challenges that and regularly update a report on the state of Mediterranean for- can affect agroforestry adoption with the aim of informing policies ests. The first edition ofState of Mediterranean Forests, published and project implementation. Challenges include tenure insecurity in 2013, has become an important reference work. The aim of this – regarding either land or its products – that undermines the adop- second edition is to demonstrate the importance of Mediterranean tion of agroforestry; small plot sizes; policies limiting access to and forests in tackling issues of global significance, such as climate the use of land by women and minority groups; and the barriers change and population growth. Mediterranean forests also have presented by some customary regimes. a role to play in helping countries meet their international commit- Drawing on practical case studies, the publication presents ments on forests, particularly the Sustainable Development Goals measures and approaches that could help drive the adoption of and the objectives of the three Rio Conventions. agroforestry. It concludes with recommendations for formulating and implementing tenure policies that promote agroforestry. Available online: www.fao.org/3/ca2081en/CA2081EN.pdf State of Mediterranean Forests 2018 – executive summary is also Available online: www.fao.org/3/CA4662en/CA4662en.pdf available in English: www.fao.org/3/ca3759en/CA3759EN.pdf French: www.fao.org/3/ca3759fr/CA3759FR.pdf

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Small-scale forest enterprises in Latin America The role of forest producer Unlocking their potential for sustainable livelihoods organizations in social protection The role of forest producer organizations in social protection social in organizations producer forest of role The

For more information, please contact:

Qiang Ma Forestry Officer Forestry Department, FAO Viale delle Terme di Caracalla

00153 Rome, Italy ISBN 978-92-5-130789-2 Email: [email protected] FORESTRY WORKING Website: www.fao.org/forestry FORESTRY PAPER WORKING FAO PAPER CA0370EN/1/07.18 10 7

Latin America’s vital small-scale forest enterprises Extending social protection through forest producer

Small-scale forest enterprises in Latin America: unlocking their potential for organizations sustainable livelihoods. FAO Forestry Working Paper No. 10. F. Del Gatto, J. The role of forest producer organizations in social protection. FAO Forestry Working Mbairamadji, M. Richards & D. Reeb. 2018. Rome, FAO. ISBN 978-92-5-131119-6. Paper No. 7. N. Tirivayi, L. Nennen & W. Tesfaye. 2018. Rome, FAO. ISBN 978-92-5- Latin America has a rich and unique experience in the development 130789-2. of small-scale forest enterprises (SSFEs). Mexico, which has had a This study identifies a broad range of factors that can enable or vigorous SSFE sector since the 1970s, was a pioneer, and several constrain the provision of social protection benefits by forest producer other countries followed suit in subsequent decades. SSFEs are organizations (FPOs). Enabling factors include secure land rights, now numerous in many Latin American countries, and some have robust leadership and management, revenues and market accessibility developed strong associations and alliances to promote and sustain for forest resources, a supportive institutional environment, and a their growth. Nevertheless, the potential of SSFEs is yet to be fully favourable social and political context in communities. realized. FPOs have opportunities to obtain financial and technical assis- This publication focuses on SSFE development in Latin America. It tance that can boost their viability and thereby create fiscal space documents their status and recent trends, identifies key challenges for the provision of social protection. The collective and participa- and opportunities, and presents recommendations for strengthening tory nature of FPOs is an asset for implementing social protection them and their role in sustainable development. benefits. International climate-change initiatives provide potential avenues for strengthening and supporting FPOs in the provision of Available online: www.fao.org/3/ca2431en/CA2431EN.pdf these benefits. Nevertheless, FPOs need to overcome an array of constraints that arise from their geographical remoteness, climate variability, insecure tenure, poor access to credit and finance, con- flict, and social and political exclusion.

Available online: www.fao.org/3/CA0370EN/ca0370en.pdf

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BOOKS

Analyse widely, act deeply Forest and farm producer organisations and the goal of climate resilient landscapes

James Mayers

Discussion Paper Forests Keywords: April 2019 Forests, Finance, Forest and Farm Facility

The contributions of producer organizations to climate resilience

Analyse widely, act deeply: forest and farm producer organisations and the goal of climate resilient landscapes. IIED Discussion Paper. J. Mayers. 2019. London, International Institute for Environment and Development (IIED). ISBN 978-1-78431- 681-5. Local organizations, thriving among smallholders who are dependent on adjacent forests or trees growing on their farms, constitute perhaps the world’s biggest and most effective force for improving rural livelihoods and sustainability. They face fast-changing pressures, however. Many forest and farm producer organizations are likely to find it useful to have an organizational goal of contributing to climate- resilient landscapes. Various international programmes can help in understanding and supporting such contributions – especially through practical actions for climate adaptation and mitigation, and forest restoration. “Landscape approaches” are helpful for analys- ing the various connected issues, while context-specific, politically savvy planning is needed for effective action. This paper explores the possible motivations and actions for climate-resilient landscapes in four sorts of forest and farm producer organizations: indigenous peoples’ organizations; community forest organizations; forest and farm producer groups; and processing groups in urban and peri-urban contexts.

Available online: https://pubs.iied.org/pdfs/13610IIED.pdf

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25ISSN 00410-6436 Unasylva or would you rather receive it electronically – or perhaps both? An international journal of forestry and forest industries Vol. 69 2018/1 If you wish to substitute your hard-copy subscription for FORESTS AND electronic-only, please write to [email protected] with SUSTAINABLE CITIES “Electronic subscription only” in the subject line. If you wish to receive both a hard copy and an electronic copy, please write to [email protected] with “Electronic and hard-copy subscription” in the subject line. Please provide the relevant contact details in the email. Unasylva will continue to be a free-subscription journal available in English, French and Spanish.

Forest and Water Programme A guide to participatory learning on forests and water The FAO Forest and Water Programme this vision by facilitating the sharing envisions a world in which resilient of knowledge and experiences, forest landscapes are managed developing the capacity of forest, e ectively to provide sustainable land and water managers to manage water ecosystem services. In the forest–water nexus, and collaboration with partners from the providing tools to support ADVANCING THE FOREST AND WATER NEXUS forest and water sectors, it supports decision-making. A CAPACITY DEVELOPMENT FACILITATION GUIDE TheThe FFAO Forest and Water Programme has countries and stakeholders in realizing pproducrod ed this module-based facilitation guide to pprroovvide background information, resource mmaterialsate and a facilitation plan to support the ddelielivvery of participatory learning workshops and More information: capacicapa ty-development programmes on the www.fao.org/in-action/forest-and- foreforests –water nexus. water-programme TheThe guidg e can be downloaded free of charge at wwwwww.fao.org/documents/card/en/c/ca6483en

Unasylva is published in English, French and Spanish. Subscriptions can be obtained by Cover: Aerial view of a village near Phang sending an e-mail to [email protected]. Subscription requests from institutions (e.g. libraries, Nga Bay, Thailand. Forests and water have companies, organizations and universities) rather than individuals are preferred in order to always been inextricably entwined. make the journal accessible to more readers. All issues of Unasylva are available online free of © iStock.com/Oleh Slobodeniuk charge at www.fao.org/forestry/unasylva. Comments and queries are welcome at [email protected] ISBN 978-92-5-131910-9 ISSN 0041-6436

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