Is Indonesian Peatland Loss a Cautionary Tale for Peru? a Two-Country Comparison of the Magnitude and Causes of Tropical Peatland Degradation
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Mitig Adapt Strateg Glob Change https://doi.org/10.1007/s11027-018-9790-3 ORIGINAL ARTICLE Is Indonesian peatland loss a cautionary tale for Peru? A two-country comparison of the magnitude and causes of tropical peatland degradation Erik Lilleskov1 & Kevin McCullough2 & Kristell Hergoualc’h3 & Dennis del Castillo Torres4 & Rodney Chimner5 & Daniel Murdiyarso3,6 & Randy Kolka7 & Laura Bourgeau-Chavez 8 & John Hribljan5 & Jhon del Aguila Pasquel4,5 & Craig Wayson9 Received: 21 November 2017 /Accepted: 4 February 2018 # This is a U.S. government work and its text is not subject to copyright protection in the United States; however, its text may be subject to foreign copyright protection 2018 Abstract Indonesia and Peru harbor some of the largest lowland tropical peatland areas. Indone- sian peatlands are subject to much greater anthropogenic activity than Peru’s, including drainage, logging, agricultural conversion, and burning, resulting in high greenhouse gas and particulate emissions. To derive insights from the Indonesian experience, we explored patterns of impact in the two countries, and compared their predisposing factors. Impacts differ greatly among Indonesian regions and the Peruvian Amazon in the following order: Sumatra > Kalimantan > Papua > Peru. All impacts, except fire, are positively related to population density. Factors enhancing Indonesian Electronic supplementary material The online version of this article (https://doi.org/10.1007/s11027-018- 9790-3) contains supplementary material, which is available to authorized users. * Erik Lilleskov [email protected] 1 USDA Forest Service, Northern Research Station, Houghton, MI, USA 2 USDA Forest Service, Northern Research Station, Madison, WI, USA 3 Center for International Forestry Research (CIFOR), Jl. CIFOR, Situ Gede, Bogor, Indonesia 4 Instituto de Investigaciones de la Amazonia Peruana (IIAP), Iquitos, Peru 5 School of Forest Resources and Environmental Science, Michigan Technological University, Houghton, MI, USA 6 Department of Geophysics and Meteorology, Bogor Agricultural University, Bogor, Indonesia 7 USDA Forest Service, Northern Research Station, Grand Rapids, MN, USA 8 Michigan Tech Research Institute, Michigan Technological University, Ann Arbor, MI, USA 9 USDA Forest Service, International Programs, Washington, DC, USA Mitig Adapt Strateg Glob Change peatlands’susceptibility to disturbance include peat doming that facilitates drainage, coastal location, high local population, road access, government policies permitting peatland use, lack of enforcement of protections, and dry seasons that favor extensive burning. The main factors that could reduce peatland degradation in Peru compared with Indonesia are geographic isolation from coastal population centers, more compact peatland geomorphology, lower population and road density, more peatlands in protected areas, different land tenure policies, and different climatic drivers of fire; whereas factors that could enhance peatland degradation include oil and gas development, road expansion in peatland areas, and an absence of government policies explicitly protecting peatlands. We conclude that current peatland integrity in Peru arises from a confluence of factors that has slowed development, with no absolute barriers protecting Peruvian peatlands from a similar fate to Indonesia’s. If the goal is to maintain the integrity of Peruvian peatlands, government policies recognizing unique peatland functions and sensitivities will be necessary. Keywords Agriculture . Fire . Forest cover loss . Indonesia . Oil palm . Peru . Plantations . Population density. Roads . Tropical peatlands 1 Introduction Peatlands are globally important for the diversity of ecosystem services they provide, not least of which is their ability to take up large quantities of carbon dioxide (CO2) and convert it to organically bound forms that are stabilized by the anoxic conditions caused by high water tables, and hence have the potential to mitigate climate change. Peat accumulations over millennial timescales have stored ~1/3 of global soil C on ~ 3% of the land surface (Page et al. 2011). However, this potential to store carbon (C) depends on whether they remain sinks or are converted to sources of CO2. The vast stores of C in peatlands are vulnerable to any changes in climate or hydrology that lower water tables, leading to increased oxidation by microorgan- isms and fire (Turetsky et al. 2015). Peatlands around the world have been drained, usually for conversion to agriculture or tree plantations. This drainage and subsequent disturbances has resulted in massive losses of CO2 from peatlands, contributing to the rapid rise in concentra- tions of greenhouse gases (Limpens et al. 2008). Tropical peatlands represent a significant fraction of global peatlands (Page et al. 2011; Gumbricht et al. 2017), and are under some of the greatest threats from human activities (Crump 2017). The most intensively studied and also most intensively impacted region in the tropics is Indonesia (see, e.g., Rieley et al. 2008 and references therein). In contrast, recently mapped extensive peatlands in Peru are much less well studied and have so far been spared the same impacts, but are on the verge of expanded development pressure (Roucoux et al. 2017). Hence explicit comparison of these two countries could provide insights that guide sustainable development in Peru. The largest areas of tropical peatlands are in Indonesia, the Congo Basin, and the Amazon Basin (Page et al. 2011;Lähteenojaetal.2012;Dargieetal.2017; Gumbricht et al. 2017). Tropical peatlands are most commonly found in lowland areas, and these lowland peatlands are mostly peat swamp forests (wetland type 20 in the Ramsar Classification; Semeniuk and Semeniuk 1997) dominated by angiosperms in Indonesia (Page et al. 2006), and a mixture of angiosperms and palms (Arecaceae) in Peru (Draper et al. 2014). Indonesian peatlands are estimated to hold from ~ 25 to ~ 55 Pg C depending on mapped area and assumptions about depth and density (Jaenicke et al. 2008;Warrenetal.2017). This represents more organic Mitig Adapt Strateg Glob Change matter than is stored in all the forest biomass in Indonesia. In Peru, lowland peatlands also represent a large C reserve—combining the peatland area (74,644 km2; Gumbricht et al. 2017) and C density (882 Mg ha−1;Draperetal.2014), these peatlands are estimated to store ~ 6.6 Pg C, about 90% of which is in peat. Despite only covering approximately 11% of the area of the Peruvian Amazon, this peatland C equals approximately 75% of mature forest biomass C in the entire Peruvian Amazon (8.80 Pg; Peru, Ministerio del Ambiente 2015b), and so is critical to any efforts to manage the GHG emissions from land use in the Peruvian Amazon. In Indonesia, peatlands have been subjected to massive development following deforesta- tion and drainage for agriculture, including monoculture pulpwood and oil palm plantations (Miettinen et al. 2012, 2016). In 2015, for the Indonesian regions of Sumatra and Kalimantan, the two regions of Indonesia with the greatest impacts, of a total of about 130,120 km2 of peatlands, an estimated 25% were in industrial plantations, 24% were in smallholder agricul- ture, 42% were degraded to varying degrees or cleared, and only 6% were pristine peat swamp forests (Miettinen et al. 2012). As a consequence of these changes, Indonesian peatlands lose globally significant amounts of C to decomposition, DOC export, and fires, especially in drought years (Page et al. 2009). For Sumatra plus Kalimantan, estimates for 2015 were 119.6 Mt C yr in peat oxidation, and a roughly equivalent annual amount from peatland fires (Miettinen et al. 2016). Although observations indicate that in Peru there is much less human impact on peatlands, with low deforestation, conversion to agriculture, drainage, and fires, there are no change estimates for Peru that are equivalent to those for Indonesia. Indonesia and Peru both lie in the tropics at similar latitudes: Peru is located between 0 and 18° S latitude, with the majority of its peatlands located north of 8 degrees latitude; Indonesia is located between 6° N and 11° S with peatlands spread across this entire range (Fig. 1). Indonesia has three major regions that harbor the majority of its peatlands: the island of Sumatra; Kalimantan, which is on the island of Borneo; and Papua, which is on the island of New Guinea (Fig. 1). These differ greatly in population and so provide a natural gradient of population impacts within Indonesia that can be compared with that of Peru. Papua is the least populated peatland region in Indonesia and most similar in anthropogenic impacts to the Peruvian Amazon where lowland peatlands are found. There are some significant differences between Indonesia and Peru that might help explain their different peatland development status. Whereas Indonesian peatlands have developed in near-coastal interfluvial regions (Dommain et al. 2014), lowland peatlands in Peru formed away from the coast in the subsiding basins to the east of the Andes Mountains. Indonesia is characterized by both ombrotrophic (rain-fed) peat domes and to a lesser extent minerotrophic (groundwater-fed) peatlands (Dommain et al. 2010, 2014). In Peru, the Pastaza-Marañon Foreland Basin contains the majority of the peatlands (Lähteenoja et al. 2012,Draperetal.2014) with a mixture of minerotrophic and domed ombrotrophic peatlands (Lähteenoja et al. 2009). The latter are typically palm swamps dominated by aguaje (Mauritia flexuosa) whereas