Assessment of methane emission and oxidation at Air Hitam Landfill site cover soil in wet tropical climate

Methane (CH4) emissions and oxidation were measured at the Air Hitam sanitary landfill in Malaysia and were modeled using the Intergovernmental Panel on Climate Change waste model to estimate the CH4 generation rate constant, k. The emissions were measured at several locations using a fabricated static flux chamber. A combination of gas concentrations in soil profiles and surface CH4 and carbon dioxide (CO2) emissions at four monitoring locations were used to estimate the CH4 oxidation capacity. The temporal variations in CH4 and CO2 emissions were also investigated in this study. Geospatial means using point kriging and inverse distance weight (IDW), as well as arithmetic and geometric means, were used to estimate total CH4 emissions. The point kriging, IDW, and arithmetic means were almost identical and were two times higher than the geometric mean. The CH4 emission geospatial means estimated using the kriging and IDW methods were 30.81 and 30.49 g m−2 day−1, respectively. The total CH4 emissions from the studied area were 53.8 kg day−1. The mean of the CH4 oxidation capacity was 27.5 %. The estimated value of k is 0.138 year−1. Special consideration must be given to the CH4 oxidation in the wet tropical climate for enhancing CH4 emission reduction.