Net greenhouse gas balance of fibre wood plantation on peat in Indonesia

Tropical peatlands cycle and store large amounts of carbon in their soil and biomass^1–5. Climate and land-use change alter greenhouse gas (GHG) fluxes of tropical peatlands, but the magnitude of these changes remains highly uncertain^6–19. Here we measure net ecosystem exchanges of carbon dioxide, methane and soil nitrous oxide fluxes between October 2016 and May 2022 from <em>Acacia crassicarpa </em>plantation, degraded forest and intact forest within the same peat landscape, representing land-cover change trajectories in Sumatra, Indonesia. This allows us to present a full plantation rotation GHG flux balance in fibre wood plantation on peatland. We find that the <em>Acacia </em>plantation has lower GHG emissions than the degraded site with a similar average groundwater level (GWL), despite more intensive land use. The GHG emissions from the <em>Acacia </em>plantation over a full plantation rotation (35.2 ± 4.7 tCO₂-eq ha⁻¹ year⁻¹, average ± standard deviation) were around two times higher than those from the intact forest (20.3 ± 3.7 tCO₂-eq ha⁻¹ year⁻¹), but only half of the current Intergovernmental Panel on Climate Change (IPCC) Tier 1 emission factor (EF)²⁰ for this land use. Our results can help to reduce the uncertainty in GHG emissions estimates, provide an estimate of the impact of land-use change on tropical peat and develop science-based peatland management practices as nature-based climate solutions.