Drylands and Climate Change Synthesis Paper. Chris Magero, 1/7/2019
1. Introduction Drylands are characterized by variable precipitation, climate variability and water scarcity and are therefore defined by aridity index (AI), which is expressed as a function of average annual precipitation, temperature and potential evapotranspiration (PET) (N. Middleton and Thomas 1997). The aridity index is therefore used to divide the drylands into four subtypes ‐ dry subhumid, semi‐arid, arid, and hyper‐arid .
Table 1 Land Classification According to Aridity Index (AI) (N. Middleton and Thomas 1997) CLIMATE TYPE ARIDITY INDEX Dryland subtypes Hyper‐arid AI < 0.05 Arid 0.05 ≤ AI ≤ 0.2 Semi‐arid 0.2 ≤ AI ≤ 0.5 Dry Subhumid 0.5 ≤ AI ≤ 0.65 Non‐Dryland Humid AI ≥ 0.65 Cold PET < 400mm
Drylands are an important biome, occupying more than 41% of the global land area and comprising grasslands, agricultural lands, forests and urban areas. Drylands provides much of the world’s food and fiber while maintaining habitats that supports biodiversity and provide ecosystem services (UNCCD 2017). They are home to over 2 billion people across the planet, and found in more than 100 countries globally, majority of which are in developing nations of Africa and Asia Error! Reference source not found..
Table 2 Regional Extent of Drylands Arid Semi‐arid Dry‐subhumid All drylands Region (1000 Km2) (%) (1000 Km2) (%) (1000 Km2) (%) (1000 Km2) (%)
Asia (incl. Russia) 6164 13 7649 16 4588 9 18401 39
Africa 5052 17 5073 17 2808 9 12933 43
Oceania 3488 39 3532 39 996 11 8016 89
North America 379 2 3436 16 2081 10 5896 28
South America 401 2 2980 17 2223 13 5614 32
Central America and 421 18 696 30 242 10 1359 58 Caribbean Europe 5 0 373 7 961 17 1359 24
1 World Total 15910 12 23739 18 13909 10 53558 40
Adapted from (Koohafkan and Stewart 2008)
The predicted rise of temperature due to climate change is expected to amplify existing risks in natural dryland systems including water scarcity, droughts and floods (IPCC 2015; Koohafkan and Stewart 2008). The likelihood of severe, pervasive and irreversible impacts on species, loss of agricultural productivity is expected to increase with the impacts weighing disproportionately on vulnerable populations (Davies et al. 2012; IPCC 2015). These impacts will have adverse consequences on the ability of dryland people and ecosystems to effectively respond to shocks as system unpredictability increases and as ecosystem services are degraded, leading to declining land productivity and biodiversity loss (UNEP 2009).
2. Dryland Ecology Like many ecosystems, drylands are under constant threat on multiple fronts owing to their complex nature and the interwoven biophysical and socioeconomic interactions which includes high temporal and spatial rainfall variability. These annual and interannual rainfall variations determine the distribution of resources including water and nutrients and consequently the distribution and abundance of vegetation. Species living under these conditions have developed very unique physiological and behavioral strategies to cope with the dramatic variations in rainfall and temperature, enabling them capitalizing on the amorphous distribution of water and nutrients across dryland landscapes. 2.1. Dryland Soils Like many ecosystems, the structure and function of drylands can be traced down to the basic processes that underpin its ecosystems services that provides benefits to people. Nutrient cycling is one of the key underpinning processes in drylands as it compiles the annual nutrient budgets for the ecosystem (Hartley et al. 2007). Nutrient accumulation in dryland ecosystem is however constrained by the extreme variations in rainfall, as well as the overall water deficiency, which ultimately drives nutrient cycling (ibid).
Soil has one of the most notable functions in nutrient cycling. It also plays a central role in food production, water storage and climate change mitigation in drylands (Laban, Graciela Metternicht, and Davies 2018; Safriel 2017). Through the accumulation of organic matter, soils provide a habitat for soil organisms which play a key role in nutrient cycling contributing to its fertility and productivity. Above and below ground organisms including bacteria, fungi, protozoa, insects, worms, other invertebrates and vertebrates (Laban, Graciela Metternicht, et al. 2018) play an important role in the carbon and water cycles contributing to the net primary productivity by aiding decomposition processes that convert organically stored nutrient in plants like nitrogen to usable forms by living plant and also determining the soil structure (ibid). The texture and structure of soil including the degree to which soil particles are bound together by organic matter, water holding properties, dissolved minerals and oxygen contained in between the spaces are rudimentary determinant of soil fertility (Safriel 2017).
Dryland soils play an extremely important role in mitigation of climate change. They store at least one third of the worlds carbon and they also occupy 42% of the earths terrestrial surface (Laban, Graciela Metternicht, et al. 2018). Soil organic carbon is important because it enhances soil properties including structure and stability, water retention capacity and porosity which are essential for improving soil fertility and productivity and supporting primary production. Dryland soils typically have low organic carbon
2 content due low primary productivity constrained by water scarcity, which affect the accumulation of soil organic matter and soil organic content. Nevertheless, dryland ecosystems quite significant for carbon sequestration and mitigation in comparison to other soils because they have little soil moisture which means that carbon has a longer residence time in the soil (Parton et al. 1995).
2.2. Biodiversity in drylands Water scarcity primarily influences the occurrence and distribution of biodiversity in drylands but as ecosystems they are shaped by underlying factors including geology, topography, rainfall, fires, herbivores and human management over millennia. Climate and latitudinal distribution have a strong influence on drylands biodiversity (Davies et al. 2012) interacting with other factors to form several distinct patchy habitats with unique features across the landscapes ranging from oasis, grasslands, mixed wood grasslands and evolving alongside them species that are equally unique that colonize the varied habitats (ibid).
The variety of habitats created by the kaleidoscope of resources spreads across the landscape and supports a wide array of species diversity including unique endemic populations that occur in these patchy specialized niches. They also support an array of ecosystem services essential for the survival of these species that also contribute to local livelihoods (ibid).
In drylands, the loss of biodiversity is caused by inter‐connected factors that include land use conversion primarily to crop farming, growth of urban settlements, invasive species and habitat fragmentation that alter migration routes of species and limits their access to previously utilizable land resources (ibid). Biodiversity loss accelerates land degradation, increases vulnerability to climate change and contributes to poverty. 2.3. Grasslands Grasslands are important drylands ecosystems contributing to more than 800 million livelihoods and supporting essential ecosystem services including forage production, carbon storage, soil protection and biodiversity conservation (NatureServe 2010).
Grasslands are globally distributed and they can be found in Europe, Asia, America, South America, Australia and Africa and they play an important role as grazing land for herbivore. They are among the largest ecosystems in the world covering 52.5 million square kilometres which is about 40.5 percent of terrestrial area, excluding Greenland and Antarctica (FAO 2005). Grasslands are the source of a substantial amount of milk (27%) and meat (23%) production in the world and supports about 1 billion livelihoods who depend on the livestock industry (ibid).
Grasslands are major vegetation types covering about one fifth of the world’s surfaces and holding more than 10% of the world’s terrestrial carbon (Parton et al. 1995). Grasslands can store up to 70 tonnes/ha soil carbon, values that are comparable with carbon stored in forest soils, but their potential has been underestimated in the past (Chuluun and Ojima 2002; Laban, Graciella Metternicht, and Davies 2018; Parton et al. 1995; UNEP 2009). They are also an important habitat for wildlife and people and provide forage for domestic livestock.
3 Globally, grasslands are under a lot of pressure of being converted to cropland and used for intensive livestock (FAO 2010). Grasslands are generally undergoing degradation as a result of grassland cultivation leading to huge releases of soil carbon into the atmosphere (FAO 2010).
The rate of carbon accumulation in grasslands varies from year to year based on climatic variability. The amount and distribution of rainfall in drylands is directly correlated to annual biomass production and Net Primary Production will therefore vary with the differences in rainfall, which can be dramatic (IPCC 2006). Annual biomass production in grasslands is substantial but it is often masked by the short growth period of grasses and annual senescence of herbaceous vegetation which quickly leave the ground bear. Additional losses of vegetation through grazing, fire, natural disturbance and harvesting essentially leaves standing biomass that does not exceed a few tonnes per hectare (IPCC 2006). Larger amount of biomass in grasslands though accumulate in woody components and below‐ground biomass which includes roots and rhizomes that are important to consider when accounting for carbon stocks in grasslands. Grassland store most of their carbon in soil with long turnover periods which may range between 100 – 1000 years, but losses are significant in the long‐term (Parton et al. 1995). Below‐ground grassland biomass may be laborious and difficult to estimate but it still remains an important component of biomass surveys in drylands and provide key information of changes in carbon stocks related to conserving or converting grasslands to other land uses and vice‐versa (IPCC 2006).
C3 and C4 plants coexist in grasslands of the world although the latter is predominantly found in forages of the tropics, subtropics and warm temperate zones (Schnyder et al. 2010). C4 photosynthesis pathway plants make only about 3 percent of all land plants species compare to the C3 and CAM photosynthesis pathway plants. C4 plants are more efficient photorespirators than C3 plants especially under condition of high temperature and low CO2. They are also tolerant to long growing seasons with access to a lot of sunlight and some are even saline intolerant and can be used for restoring sites that are affected by salinization. C3/C4 grasslands also operate as agroecosystems provide forage for grazing livestock and therefore their management is important to establish a stable cycling of carbon and nitrogen cycles. In the face of climate change with typical high temperatures and increased atmospheric CO2 concentration, grasslands will play an important role in carbon sequestration. 2.4. Dryland forest and woodlands Dry forest and woodland occupy 18 percent of dryland systems across the world with the probability of their occurrence generally decreasing with increasing aridity (Safriel et al. 2005). They play an important role in biodiversity conservation, watershed protection and regulation of water flow, desertification control, soil improvement and climate stabilization through carbon sequestration (Center for International Forestry Research 2010).
Dry forests and woodlands have less above ground woody biomass in comparison to tropical forests, but they play an important role in sequestering and storing soil organic carbon owing to the sheer expanse of land that drylands occupy. Studies have estimated that miombo woodland in Southern Africa for example, has the potential of storing more than 100 tonnes of carbon per hectare (Center for International Forestry Research 2010). Human disturbances including deforestation, agriculture, fire, charcoal production and collection of firewood in dryland forests result in land degradation and lead to the net loss of stored carbon in drylands (Center for International Forestry Research 2010) increasing the risk of climate change.
4 2.5. Role of fire in drylands Fire is an important feature of many dryland ecosystems, playing a role in ecosystem renewal and determining the structure of ecological communities in many grasslands and woodlands. It contributes to maintaining ecosystem processes but it also plays an important role in climate change as it consumes ecosystem biomass, impacts on the carbon cycle and also contributes to emissions of Green House Gases and aerosols including albedo that impacts on black carbon (Sommers, Coloff, and Conard 2011). On the other hand, in some cases fire can play a role in climate change mitigation. In traditional shifting cultivation systems in many tropical countries, net emissions have been found to be minimized or neutralized through regeneration of the fields to secondary forest following the harvesting of several crops. Emerging scientific research suggests shifting cultivation involving the use of fire can in some circumstances become a net sink as carbon is leached to lower horizons in the soil profile below swidden fields (Mutuo et al., 2005)1.
As a tool, fire is often used for the removal of unpalatable grasses to enable fresh regrowth and control woody vegetation. The absence of fire over many years in a grasslands leads to accumulation of biomass, which if accidentally ignited by can result in fierce and destructive fires that can have devastating results on the ecological communities (FAO 2010). The outcomes of fire depend on its intensity, seasonality, frequency and type. While frequent burning may be undesirable, long periods between fires can also have detrimental effects on vegetation communities. 2.6. Dryland Livelihoods: Land use, land tenure and culture Grassland are managed under different tenure and management regimes, including large scale communal governance arrangements and private land ownership. Communal management on a vast scale is practiced in much of Africa and the majority of Central Asia, whereas private holdings (also often on a large scale) is common in the Americas, Australia and Europe. There has been a tendency to equate traditional communal management with subsistence production, but there is growing awareness that traditional and communal systems are not only commercializing, but they can be more productive than private tenure systems (Davies et al., 2012).
The majority of rural populations living in the drylands depend either on livestock husbandry or small scale agriculture. The yields and returns in dryland systems ordinarily fluctuate greatly within and between years, which the communities cope with by adopting different livelihood strategies. Traditional dryland systems have over many decades evolved alongside these conditions and developed mechanisms and strategies for coping and managing risks which include tracking resources through livestock mobility. Mobility represents a key coping strategy in pastoral systems. Mobility allows human and livestock to make use of the vast natural resources in a landscape without overexploitation on localized sites. Mobility itself is quite complex relating to abundance and distribution of biodiversity and water (Davies et al. 2012; Middleton 2016; UNCCD 2017).
Although mobility itself may be driven by the erratic nature of rainfall, it is not haphazard but related to long‐term traditional tenure agreements nested into the larger systems of governance, rights and responsibilities (Davies et al. 2012). Over time, ecosystems and people in the drylands have changed and
1 https://unfccc.int/resource/docs/2009/smsn/ngo/104.pdf
5 with it the governance systems, tenure, land use and occupancy rights which have drastically disrupted their ability to continue accessing and utilizing natural resources in the same ways (Davies et al. 2012).
Since production systems in drylands are highly dependent on the erratic climatic conditions, production is often therefore carried out on the edge of ecological thresholds, with opportunism as the ingredient of survival. Climatic shifts occasioned by climate change that will introduce an additional tier of unpredictability can therefore be expected to have far reaching negative impacts on livelihoods that lead to increased vulnerability, food insecurity and dilapidating poverty.
Land uses, classified by subtypes include rangelands, cultivated lands and urban land areas. More than 90% of the drylands support rangeland and agricultural activities (Safriel et al. 2005) which is often appreciated as a mosaic of pastoral and agropastoral activities across landscapes . Dryland host more than 2.1 billion people with more than 900 million found in urban areas with projected growth of 60% by 2030 (Bai et al. 2005; Safriel et al. 2005). Such growth will have a direct impact on the use of drylands especially on ecosystem services depending on how they are managed and developed.
Table 3 Land uses in drylands adapted from (Safriel et al. 2005)
Rangelands Cultivated Urban Other Area Share of Area Share of Area Share of Area Share of Dryland Dryland Dryland Dryland Subtype Subtype Subtype Subtype (sq km) (percent) (sq km) (percent) (sq km) (percent) (sq km) (percent) Dry subhumid 4,344,897 34 6,096,558 47 457,851 4 1,971,907 16 Semiarid 12,170,274 54 7,992,020 35 556,515 2 1,871,146 8 Arid 13,629,625 87 1,059,648 7 152,447 1 822,075 5 Hyper‐arid 9,497,407 97 55,592 0.6 74,050 1 149,026 2 Total 39,642,202 65 15,203,816 25 1,240,863 2 4,814,155 8
Traditionally, drylands have served multiple livelihood purposes including hunting, gathering, cropping, animal husbandry and fishing, with semiarid and dry sub‐humid lands meeting the greatest potential for trade‐off and synergies between different livelihood activities. Systems like agropastoralism and silvopastoralism that have emerged over time to redress the issues caused by environmental, social, economic and political pressures (Safriel et al. 2005).
For pastoralism, secure land tenure or grazing rights is essential for sustaining livelihoods and also to attract investment in the sustainable management of grasslands. Examples show that where grassland production is purely commercial, which includes part of South Africa, Patagonia, the Campos and Central – North America, they attract investment in infrastructure, water, fencing and pasture improvement, and can also be used as collateral for securing loans (FAO 2005). However, those systems have also been shown to be less economically productive, more exposed to risk, and support a greatly reduced human population, and therefore have questionable relevance in many developing countries.
More traditional pastoral systems have less clear land tenure agreements which are usually managed under customary rules and traditional authorities. State regimes have not recognized the rights of pastoralists in comparison to other groups like farmers, which causes a lot of uncertainty and has contributed to conflict. Traditional pastoral tenure systems may also not be strong enough to prevent the
6 state from confiscating the land for other development prospects for example mining, oil exploration or building nature reserves, since pastoralist may use a piece of grassland only in a particular season. While cropland can be easily allocated to individual, the extensive nature of pastoralism to utilize vast landscapes make individual allocation problematic as it is may be impossible to equitably allocate resources (ibid).
Common property rights in drylands are often essential for the sustainable management of land by ensuring that customary arrangements can regulate the use of resources. Strong governance, which traditional pastoralism has, depends on the strength of institutions for resources allocation and control. Emerging states however have over the years weakened the traditional institutions in rangelands without putting in place adequate alternatives (ibid).
Poor governance in the face of climate change will therefore exacerbate the deterioration of land resources including water and vegetation for grazing as management and decision‐making will be deficient of pertinent knowledge and information necessary for communities to respond to climate change. Improving governance therefore means strengthening the relationship between communities and the state, where indigenous local knowledge must make part and parcel of political, economic and environmental decisions (Davies et al. 2012).
Dryland people have evolved alongside their ecosystems which inspire them and provides them with their identity. Ecosystem functions and cultural identity provide communities with incentives to conserve the integrity of their ecosystems and its diversity. The co‐evolution of culture and their landscape has generated diverse knowledge responses to land resource management including water harvesting techniques, climate forecasting, cultivation practices and use of medicinal plants among others.
7 3. Drylands and Climate Change
Climate change is predominantly driven by the buildup of greenhouse gasses, including atmospheric CO2, and this is in turn influenced by the uptake and storage of atmospheric carbon by plants (carbon sequestration), the dissipation of carbon back to the environment during photosynthesis, and the plant parts, including the live and dead, above and below‐ground biomass. The sustained emissions of carbon dioxide and other greenhouse gases is linked to fossil fuel combustion and land use change and would result in the loss of ecosystems services and biodiversity and impact directly on livelihood, food and human security (IPCC 2015). Changes in rainfall patterns and CO2 concentration in the tropics are expected to increase the Net Primary Productivity (NPP) in the short‐term, but in the long‐term could lead to severe droughts reducing NPP and increasing fire frequency (IPCC 2001).
Climate change is a significant driver of land degradation in drylands and because of this scientists predict that drylands will expand significantly by 2100. Global drylands are estimated to expand by 10 % (or 5.8 × 106 km2) under high greenhouse gas emissions by the end of the 21st century with as much as 80% occurring in developing countries (N. Middleton and Thomas 1997). About 25 – 30% of drylands already suffer some form of land degradation (Bai et al. 2008; Bao Le Quang, Nkonya Ephraim 2014). In drylands, the most widespread form of land degradation is soil erosion with 87% of degradation being caused by water or wind (FAO 2015). Soil erosion is often a result of several factors including loss of vegetation cover, lack of soil conservation practices and grazing pressure. Vegetation for instance provides direct cover for the soil from element of erosion including wind and rain and the root networks also stabilize soil by binding them together (Safriel 2017). Land degradation in drylands can also manifests itself through the loss of soil organic carbon (IUCN 2015a).
In drylands, climate change is projected to have a direct impact on water and water resources with dramatic shifts in rainfall patterns: both the quantity and the temporal and spatial distribution. Higher temperatures and high rainfall variability will have a direct impact on the ground water availability due to change in the frequency and intensity of precipitation and increased evaporation rates. However, these are also affected by other factors, including land degradation, which has many underlying drivers, some of which are also drivers of climate change. Land degradation can reduce ground water recharge and storage and increases water runoff due to soil compaction. The depletion of water, either as soil moisture, groundwater, flowing rivers or reservoirs, disrupts water cycles and leads to water scarcity (Koohafkan and Stewart 2008; UNCCD 2017). Water scarcity affects among other things the length of growing season and NPP.
Climate change, which is expected to manifest as increased frequency and intensity of extreme climate events including droughts (IPCC 2015), is particularly of concern in drylands where species and communities already have to cope with dramatic variations in temperature and droughts (UNCCD 2017). Drought is a multifaceted concepts that can be described in relation to the degree of dryness (meteorological drought), deficits in soil water moisture affecting growth (Agricultural drought), deficit in surface and subsurface hydrology (hydrological drought) and to socioeconomic factors (socioeconomic drought). Drought has a direct impact on hydrological connectivity including surface and subsurface water flow and indirectly affects agriculture, plant productivity and plant survival.
Dryland species are uniquely adapted to extreme climatic uncertainly whether it is rainfall variability within and between years or stochastic events such as drought and floods (Davies et al. 2012). Plants and animals have devised extremely ingenious ways to adapt to these conditions and still make use of the
8 scarce resources. Dryland societies are similarly adapted, and indeed their management strategies often resemble the behavioral adaptations of dryland species.
Pastoral mobility, diversification of livestock species, and maximization of herd numbers are some pastoralist insurance strategies that communities use to manage extreme uncertainty in their environment. Drylands’ ecological dynamics and environmental change models suggest that drought‐ induced changes may push dryland dynamics beyond its biophysical thresholds resulting in a long‐term decline in agricultural productivity. The ability of pastoral communities to cope is anchored on function of key traditional institutions. However, the persistent breakdown of these institutions and other socioeconomic changes including change in land tenure systems, shift to crop farming in a narrow range of commodities and reduced ability of livestock to move across landscapes is increasing community vulnerability within drylands (Fraser et al. 2011). With already diminished system resilience, climate change will impact adversely on dryland livelihoods and their ability cope and adapt where there are weak or dysfunctional systems and institutions that enable efficient exploitation of drylands resources, leading to increased poverty.
Dryland soils are extremely vulnerable to wind and water erosion because of their structure. Increased precipitation and floods due to climate change is expected to exacerbate the situation. As top soil is lost, the soil nutrient content including the soil organic carbon is also lost as soil fertility and land productivity diminishes (IUCN 2015b). Reduced land productivity in drylands has far reaching consequences for global food systems considering that more than 44% of the world’s agriculture is located in drylands with Africa and Asia supplying 66% of food production (Davies et al. 2012). The complex changes to land productivity due to climate change are severely threatening the potential for food production in drylands and contributing to food insecurity and persistent poverty (ibid).
Grasslands accumulate carbon stocks that vary in size depending on vegetation composition of grassland types. Increasing the area under grassland increases the rate of CO2 sequestration and protecting them through sustainable land management practices prevent to loss of carbon and carbons stocks as CO2 emissions (IUCN 2010; Laban, Graciela Metternicht, et al. 2018). Conversion of grasslands to annual croplands can result into loss of up to 60% of soil carbon stock and up to 95% loss of above ground carbon (Laban, Graciela Metternicht, et al. 2018). Many of the world grasslands especially in semi‐arid areas are incrementally being cleared for crop farming the demand for food increases.
The land use and management has a strong bearing on how much carbon can be stored, sequestered or released in form of greenhouse gases under different climate regimes. In drylands conversion grasslands and dryland forests into agricultural land is steadily increasing (Center for International Forestry Research 2010; FAO 2005). When this happens soil carbon and nitrous oxide is released into the atmosphere which contributes to climate change.
The conversion of grasslands and woodlands to cropland causes soil disturbance, loss of vegetation cover, increased fire incidence or reduces soil aggregation may cause land degradation and increase greenhouse gas emissions (FAO 2015; UNCCD 2017). The impaired soil function of carbon sequestration association with land productivity loss also undermines food security, climate change at local and global scale (Safriel 2017).
Land degradation is the loss of the biological and economic productivity and complexity of land which impacts vegetation cover, soil, biomass, biodiversity, system resilience or ecosystem services (UNCCD
9 2017). In drylands, it is referred to as desertification. Land degradation has led to loss of productivity of more than 20 percent of the world’s arable land over the last 20 years and affected more than 1.3 billion people around the world who live in degrading agricultural land. Land degradation leads to loss of global ecosystem services which have been estimated at US$ 6.3 to 10.6 trillion annually (IUCN 2015a).
The challenge for drylands is therefore to understand the impacts of climate change on different land uses, the concurrent management regimes and their outcomes in addressing the challenge of climate change in order to provide appropriate incentives that can contribute to climate change mitigation and adaptation vis‐à‐vis sustainable development.
Drylands have however not received the prominence they deserve in climate change discussions despite their potential role to play a significant role in climate change adaptation and mitigation. Interventions that restores and enhances the conditions of dryland soils have a huge potential in impacting the global climate change patterns whether it is improving land productivity through better management, increasing ecosystem stability, investing in sustainable land management will ultimately increases carbon sequestration and decreases loss of carbon stocks from arid drylands, and provide a formidable front to address climate change.
4. Responding to the challenge of Climate Change in drylands Conserving and restoring drylands present an enormous opportunity to address climate change impacts in this unique environment. 1. Restoring dryland ecosystems improves their health and functioning, including nutrient cycling that
enhances their ability to absorb and store atmospheric CO2, particularly in soils.
Investing in this restoration of dryland ecosystems is a cost‐effective approach to climate change mitigation.
2. Maintaining soil health, and the organic carbon in the soil, can be achieved through perennial plant cover. This also increases soil productivity and enhances soil water conservation.
3. The key to climate change adaptation in drylands is to maintain ecosystem resilience and to strengthen existing social and economic adaptations.
Resilience building involves recognizing and sustaining practices, including those that involve traditional governance structures, which ensure land is appropriately managed at scale. These strategies include planting drought‐tolerant crops, water‐efficient cropping practices, herd diversification, and livestock mobility.
4. Mobility is a coping strategy that allows humans and livestock to use the vast natural resources in a landscape without overexploiting specific sites.
This also provides insurance against uncertainty. This practice is quite complex, and is hinged on the abundance and distribution of biodiversity and water. It is rooted in a larger system of governance, rights and responsibilities that allow different communities to manage and share resources through long‐term traditional tenure agreements. These traditional structures of governance have changed over time, disrupting the access and use of natural resources especially grazing and pasture
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