Carbon Stocks from Peat Swamp Forest and Oil Palm Plantation in Central Kalimantan, Indonesia

Abstract

Conserving high carbon density tropical peat forests is one of the most cost-efficient strategies for climate change mitigation at national and global levels. Over past decades, large areas of tropical peat forests have been converted to oil palm plantation in Indonesia resulting in significant carbon emissions into the atmosphere. Here, we quantified the ecosystem carbon stocks in a total of six sites: two primary peat swamp forest sites, one secondary peat swamp forest site, and three young oil palm plantation sites in Tanjung Puting, Central Kalimantan, Indonesia. We further determined potential carbon emissions from vegetation change due to peat swamp forest conversion to oil palm plantation. The mean total ecosystem carbon stock of primary and secondary peat swamp forests were 1770 ± 123 Mg C/ha and 533 ± 49 Mg C/ha, respectively. In contrast, the mean carbon stock of oil palm plantations was 759 ± 87 Mg C/ha or 42% of peat swamp forests. The ratio of the aboveground to belowground C stock was highest in secondary forest with an estimated value of 0.48, followed by primary forest at 0.19 and oil palm plantation at 0.04. Using a stock difference approach, we estimated potential carbon emissions from vegetation change resulting from the conversion of primary peat swamp forest to oil palm plantation of 640 ± 114 Mg CO2/ha. Finally, while restoring peatlands is important, avoiding peat conversion is imperative for Indonesia’s climate change mitigation effort.

Spatio-Temporal Variability of Peat CH4 and N2O Fluxes and Their Contribution to Peat GHG Budgets in Indonesian Forests and Oil Palm Plantations

“…Peat depth varied in forest plots from less than 50 cm at the plot closest to the river to almost 3 m at the plot located farthest from the river. The plot closest to the river (FOR-1) was a 30-year-old secondary forest, managed as an agroforestry garden before Tanjung Puting National Park was established in 1982 and communities were moved across the Sekonyer river (Novita et al, 2020; according to interviews with community members). FOR-1 vegetation was dominated by pioneer species such as Macaranga motleyana (Euophorbiaceae), Buchanania sessifolia (Anacardiaceae), Baccaurea stipulate (Phyllanthaceae), and Litsea firma (Lauraceae) (Novita et al, 2020).…”

“…The plot closest to the river (FOR-1) was a 30-year-old secondary forest, managed as an agroforestry garden before Tanjung Puting National Park was established in 1982 and communities were moved across the Sekonyer river (Novita et al, 2020; according to interviews with community members). FOR-1 vegetation was dominated by pioneer species such as Macaranga motleyana (Euophorbiaceae), Buchanania sessifolia (Anacardiaceae), Baccaurea stipulate (Phyllanthaceae), and Litsea firma (Lauraceae) (Novita et al, 2020). The other two forest plots (FOR-2, FOR-3) were primary forests dominated by Vatica oblongifolia (Dipterocarpaceae) and Santiria apiculate (Burseraceae) (Novita et al, 2020).…”

“…FOR-1 vegetation was dominated by pioneer species such as Macaranga motleyana (Euophorbiaceae), Buchanania sessifolia (Anacardiaceae), Baccaurea stipulate (Phyllanthaceae), and Litsea firma (Lauraceae) (Novita et al, 2020). The other two forest plots (FOR-2, FOR-3) were primary forests dominated by Vatica oblongifolia (Dipterocarpaceae) and Santiria apiculate (Burseraceae) (Novita et al, 2020). Our oil palm plots were nucleus estate smallholder plantations, an important part of the palm oil industry in Indonesia.…”

Impact of Land Use Conversion on Carbon Stocks and Selected Peat Physico-chemical Properties in the Leyte Sab-a Basin Peatland, Philippines

“…Tropical peatland forests provide numerous ecosystem services including carbon storage, and thus they are important for climate change mitigation (Murdiyarso et al 2009;Novita et al 2021). However, in this study, it was found that aboveground carbon storage of peatland forest particularly in standing trees was signi cantly altered by land use conversion.…”

Seasonal litter contribution to total peat respiration from drained tropical peat under mature oil palm plantation

“…The litter in tropical peat swamp forest is composed predominantly of woody debris, coarse and fine roots, and leaf litter (Miyajima et al, 1997), contributing a remarkable portion for total and heterotrophic respiration on the surface (Hirano et al, 2009;Sundari et al, 2012), also similar within the mineral soil rainforest (Zhou et al, 2013). However, different species are grown as primary plants and understory cover in oil palm plantations (Sabiham et al, 2012;Ashton-Butt et al, 2018;Novita et al, 2020). Peatland monoculture ecosystem sequestered C with a broad range (Khasanah et al, 2015;Novita et al, 2020), releasing heterogeneous C sources ranging from pruned palm fronds with high lignin content (Moradi et al, 2014;Pulunggono et al, 2019) to the easily degraded understory cover material (Amatangelo and Vitousek, 2009).…”