Carbon emissions from South‐East Asian peatlands will increase despite emission‐reduction schemes

Abstract

Carbon emissions from drained peatlands converted to agriculture in South-East Asia (i.e., Peninsular Malaysia, Sumatra and Borneo) are globally significant and increasing. Here, we map the growth of South-East Asian peatland agriculture and estimate CO emissions due to peat drainage in relation to official land-use plans with a focus on the reducing emissions from deforestation and degradation (REDD+)-related Indonesian moratorium on granting new concession licences for industrial agriculture and logging. We find that, prior to 2010, 35% of South-East Asian peatlands had been converted to agriculture, principally by smallholder farmers (15% of original peat extent) and industrial oil palm plantations (14%). These conversions resulted in 1.46-6.43 GtCO of emissions between 1990 and 2010. This legacy of historical clearances on deep-peat areas will contribute 51% (4.43-11.45 GtCO ) of projected future peatland CO emissions over the period 2010-2130. In Indonesia, which hosts most of the region's peatland and where concession maps are publicly available, 70% of peatland conversion to agriculture occurred outside of known concessions for industrial plantation development, with smallholders accounting for 60% and industrial oil palm accounting for 34%. Of the remaining Indonesian peat swamp forest (PSF), 45% is not protected, and its conversion would amount to CO emissions equivalent to 0.7%-2.3% (5.14-14.93 Gt) of global fossil fuel and cement emissions released between 1990 and 2010. Of the peatland extent included in the moratorium, 48% was no longer forested, and of the PSF included, 40%-48% is likely to be affected by drainage impacts from agricultural areas and will emit CO over time. We suggest that recent legislation and policy in Indonesia could provide a means of meaningful emission reductions if focused on revised land-use planning, PSF conservation both inside and outside agricultural concessions, and the development of agricultural practices based on rehabilitating peatland hydrological function.

Impact of forest plantation on methane emissions from tropical peatland

“…The coastal lowlands of Southeast Asia host one‐third of tropical peatlands, with the majority located in Indonesia (Gumbricht et al, ; Page, Rieley, & Banks, ), and they represent unrecognized and poorly understood components of the CH 4 cycle (Pangala, Moore, Hornibrook, & Gauci, ; Wong et al, ). Since the 1980s, extensive areas of Southeast Asian peatlands have experienced land‐cover changes (Miettinen, Shi, & Liew, ; Wijedasa et al, ), driven by transmigration, local population growth, and ongoing economic development. The 2015 land‐cover distribution for the insular Southeast Asian peatlands reveals that half of all former peatland forest is managed as either small‐holder agriculture or industrial plantation, while around 29% is characterized as intact or degraded natural peat swamp forest (Miettinen et al, ).…”

“…Since the 1980s, extensive areas of Southeast Asian peatlands have experienced land-cover changes (Miettinen, Shi, & Liew, 2016;Wijedasa et al, 2018), driven by transmigration, local population growth, and ongoing economic development. The 2015 land-cover distribution for the insular Southeast Asian peatlands reveals that half of all former peatland forest is managed as either small-holder agriculture or industrial plantation, while around 29% is characterized as intact or degraded natural peat swamp forest (Miettinen et al, 2016).…”

Fluvial organic carbon fluxes from oil palm plantations on tropical peatland

“…Oil palm has played a central role in land-use change within Indonesia and Malaysia over the last few decades, driven by global consumer demand for vegetable-oil-based products and the exceptionally high productivity of oil palm compared to other oil-producing crops (Wicke et al, 2008(Wicke et al, , 2011Schrier-Uijl et al, 2013;Gandaseca et al, 2014;Cole et al, 2015;Wijedasa et al, 2017). Over the next 30 years around 50 % of the remaining peat swamp forest in Indonesia is at risk of land conversion, predominately for oil palm cultivation, despite a recent moratorium on the issuing of new concession licences for agriculture or logging in peatlands (Wijedasa et al, 2018). Peatland oil palm expansion is also prevalent within the Malaysian state of Sarawak (SarVision, 2011;Cole et al, 2015).…”

Fire in the Swamp Forest: Palaeoecological Insights Into Natural and Human-Induced Burning in Intact Tropical Peatlands

“…Draining and/or forest clearing, which accompanies the majority of peat swamp forest land-use change, leads to highly flammable conditions, and inevitably subsidence (Hooijer et al, 2011) and ongoing carbon emissions (Wijedasa et al, 2018). This often results in peatlands becoming "unmanaged wastelands" or entirely converted to agriculture (Miettinen et al, 2012b).…”