EGU22-9928
https://doi.org/10.5194/egusphere-egu22-9928
EGU General Assembly 2022
© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.

CH4 and N2O emissions from smallholder agricultural systems on tropical peatlands in SE Asia

Antonio Jonay Jovani-Sancho1,2, Patrick O'Reilly3, Gusti Anshari4,5, Xin Yi Chong6, Neil Crout1, Christopher D. Evans2, Stephanie Evers6,7, Jing Ye Gan6, Christopher N. Gibbins6, Jamaludin Jamaludin4, Adi Jaya8, Susan Page3, Yosep Redin8, Caroline Upton3, Paul Wilson1, and Sofie Sjögertsten1
Antonio Jonay Jovani-Sancho et al.
  • 1School of Biosciences, University of Nottingham, Loughborough, LE12 5RE, UK (jonay.jovanisancho@nottingham.ac.uk)
  • 2UK Centre for Ecology and Hydrology, Bangor, LL67 2UW, UK
  • 3School of Geography, Geology & the Environment, University of Leicester, Leicester, LE1 7RH, UK
  • 4Magister of Environmental Science, Universitas Tanjungpura (Untan), Pontianak, West Kalimantan 78124, Indonesia
  • 5Soil Science Department, Universitas Tanjungpura (Untan), Pontianak, West Kalimantan 78124, Indonesia
  • 6School of Environmental and Geographical Sciences, University of Nottingham Malaysia, Malaysia
  • 7School of Biological and Environmental Sciences, Liverpool John Mores University, Liverpool, 45 L3 3AF, UK
  • 8Faculty of Agriculture, University of Palangka Raya, Palangka Raya 73112, Indonesia

Few studies have measured GHG emissions from smallholder agricultural systems in tropical peatlands, or non-CO2 emissions from human-influenced tropical peatlands more generally.  The aim of this study was to quantify CH4 and N2O fluxes from agricultural landscapes on tropical peatlands in SE Asia and assess their environmental controls. The study was carried out in four peatland areas in Malaysia and Indonesia. At each site CH4 and N2O fluxes and environmental parameters was measured in four land use types, short rotation agricultural crops, oil palm plantation, tree plantation, and adjacent secondary/degraded forest.  annual CH4 emissions were 1.8 ± 1.2, 2.1 ± 0.8, 2.3 ± 0.4, 6.1 ± 1.2 and 105.6 ± 18.1 kg CH4 ha-1 year-1 at the degraded forest, tree plantation, oil palm, cropland and intact forest land use classes, respectively, while annual N2O emissions were 0.6 ± 0.3, 3.3 ± 0.9, 12.5 ± 3.0, 18.0 ± 7.3 and 32.7 ± 5.8 kg N2O ha-1 year-1 at the intact forest, tree plantation, degraded forest, oil palm and cropland land use classes, respectively. CH4 emissions were strongly determined by WTD following an exponential relationship with production of CH4 starting when annual WTD was above –25 cm. By contrast, N2O emissions were strongly correlated with TDN, following a log-normal relationship. The optimum TDN concentration for N2O production was 10 mg N L-1 and beyond this threshold, the availability of mineral N was no longer limiting the N2O production, with other environmental variables such as WTD, soil water content, and temperature becoming more important. The new emission factors for CH4 and N2O presented here should be included in country level GHG inventories to improve their accuracy. The strong impact of substrate supply on N2O emissions shows that fertilisation practices strongly impact net emissions suggesting that policies that result in reduced fertilisation rates can directly cut emissions.

How to cite: Jovani-Sancho, A. J., O'Reilly, P., Anshari, G., Chong, X. Y., Crout, N., Evans, C. D., Evers, S., Gan, J. Y., Gibbins, C. N., Jamaludin, J., Jaya, A., Page, S., Redin, Y., Upton, C., Wilson, P., and Sjögertsten, S.: CH4 and N2O emissions from smallholder agricultural systems on tropical peatlands in SE Asia, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-9928, https://doi.org/10.5194/egusphere-egu22-9928, 2022.