Degradation increases peat greenhouse gas emissions in undrained tropical peat swamp forests

Share this
Tropical peat swamp degradation can modify net peat greenhouse gas (GHG) emissions even without drainage. However, current Intergovernmental Panel on Climate Change (IPCC) guidelines do not provide default emission factors (EF) for anthropogenically-degraded undrained organic soils. We reviewed published field measurements of peat GHG fluxes in undrained undegraded and degraded peat swamp forests in Southeast Asia (SEA) and Latin America and the Caribbean (LAC). Degradation without drainage shifted the peat from a net CO2 sink to a source in both SEA (- 2.9 +/- 1.8 to 4.1 +/- 2.0 Mg CO2-C ha-1 yr-1) and LAC (- 4.3 +/- 1.8 to 1.4 +/- 2.2 Mg CO2-C ha-1 yr-1). It raised peat CH4 emissions (kg C ha-1 yr-1) in SEA (22.1 +/- 13.6 to 32.7 +/- 7.8) but decreased them in LAC (218.3 +/- 54.2 to 165.0 +/- 4.5). Degradation increased peat N2O emissions (kg N ha-1 yr-1) in SEA forests (0.9 +/- 0.5 to 4.8 +/- 2.3) (limited N2O data). It shifted peat from a net GHG sink to a source in SEA (- 7.9 +/- 6.9 to 20.7 +/- 7.4 Mg CO2-equivalent ha-1 yr-1) and increased peat GHG emissions in LAC (9.8 +/- 9.0 to 24.3 +/- 8.2 Mg CO2-equivalent ha-1 yr-1). The large observed increase in net peat GHG emissions in undrained degraded forests compared to undegraded conditions calls for their inclusion as a new class in the IPCC guidelines. As current default IPCC EF for tropical organic soils are based only on data collected in SEA ombrotrophic peatlands, expanded geographic representation and refinement of peat GHG EF by nutrient status are also needed. View source
Year

2024

Secondary Title

Biogeochemistry

Volume

167

Number

167

Pages

59-74

DOI

10.1007/s10533-023-01110-2

Keyword(s)

Soil; Land-use change; Emission factor; Southeast Asia; Latin America; and the Caribbean; land-use change; soil respiration; methane emissions; carbon stocks; 3; ecosystems; water-table; ch4 fluxes; peninsular malaysia; palm; plantations; co2 emissions; Environmental Sciences & Ecology; Geology

Classification
Form: Journal Article
Geographical Area: Southeast Asia

Supporter & Funder