[A-CG39] Biogeochemical cycles in Land Ecosystem

[ACG39-05] Carbon dioxide balance of an oil palm plantation on tropical peat

*Takashi Hirano¹, Frankie Kiew², Ryuichi Hirata³, Guan Xhuan Wong², Edward Baran Aries², Kevin Kemudang², Joseph Wenceslaus², Lo Kim San², Lulie Melling² (1.Research Faculty of Agriculture, Hokkaido University, 2.Sarawak Tropical Peat Research Institute, 3.CGER, National Institute for Environmental Studies)

Keywords:CO2 flux, Eddy covariance technique, Tropical peat swamp forest, Deforestation, Drainage

Oil palm plantations have been expanding rapidly over recent decades especially in Indonesia and Malaysia, the two largest oil palm producers in the world. The greatest concern associated with such expansion is its environmental impact. Carbon rich tropical peat swamp forest is also not excluded from such expansion, because it is accessible for developers. Carbon dioxide (CO₂) release through accelerated oxidative peat decomposition is one of the main environmental concerns in the land conversion from peat swamp forest into oil palm plantations, which were drained and compacted to increase yield. Changes in aboveground biomass also might significantly alter the CO₂ exchange dynamics of the ecosystems. Despite the possible significant changes in the CO₂ balance through the land conversion, there is still no study on the ecosystem-scale CO₂ balance of oil palm plantations established on tropical peat. Thus, we have monitored CO₂ flux above an oil palm plantation established on tropical peatland in Sarawak, Malaysia by the eddy covariance technique since 2011. We quantify the annual CO₂ balance of the oil palm plantation and compare it with that of a secondary peat swamp forest in the same region.