Increases in Greenhouse Gases Following the Use of Peatlands for Agricultural Areas

Abstract

Peatlands with very high C contents are generally considered a source of greenhouse gas (GHG) emissions. This research aimed to quantify the changes in peatland characteristics and GHG emission from the conversion of peatlands to agricultural areas. Height of water table, pH, electrical conductivity (EC), redox potential (Eh), organic carbon (OC), hot water-soluble C, total-N, the concentrations of NH4+, and NO3- , soluble-Al, soluble Fe, and the emission of CH4, CO2 and N2O were quantified before and after land clearing of peats for agriculture. Results of study showed that pH, EC, OC contents, hot water-soluble-C, and total-N did not change after peatland clearing for agriculture. On the other hand, the concentrations of NH4+, NO3-, soluble-Al, soluble-Fe, redox potential and height of water table increased significantly after the peatland land clearing. Methane emissions from peatlands before peatland clearing were in the range of 0.13-0.22 mg C m-2h-1increased significantly to 0.14-0.31 mg C m-2h-1after the peatland clearing. The land clearing of peatlands for agricultural practices also caused increases in CO2 and NOx emissions by 85% and 76%, respectively. Changes in GGH emissions were not related to the changes in substrates quality of peats (OC contents, total-N and hot water- soluble-C). Results of the study indicate that increases in the GHG emission following the use of peatlands for agricultural areas are attributed to the changes in the peat characteristics.