Reduction in carbon dioxide and methane production of tropical peatlands due to coal fly-ash application

Abstract

Tropical peatlands with very high organic carbon (C) contents have the potential to be a source of carbon dioxide (CO2) and methane (CH4) production. Therefore, the management of tropical peatlands is essential to prevent peat decomposition and to reduce the production of CO2 and CH4. We added different amounts of coal fly-ash (CFA) (0, 25, 50, 75, 100 and 125 Mg ha−1) to tropical peats in a laboratory study to quantify changes in CO2 and CH4 production in response to the application of CFA. The amounts of CO2 and CH4 produced by the mixtures of peats and CFA over 90 days were monitored on weekly basis. Peat pH, concentrations of hot-water soluble C, calcium and iron were also measured at the end of incubation period. Results of study revealed that the application of CFA up to 50 Mg ha−1 did not change the production of CO2 and CH4, while the application of CFA by 50–125 Mg ha−1 reduced 12–24% of CO2 and 9–15% of CH4. The decrease in the production of CO2 and CH4 due to the relatively high amount of CFA application was related to the decrease in the amount of hot soluble organic C and the increase in the concentrations of Ca and Fe. This study demonstrates the potential of CFA as waste materials from coal processing of power plants in reducing CO2 and CH4 emissions of tropical peatlands.

Reduction in Carbon Dioxide Production of Tropical Peatlands Under Nitrogen Fertilizer with Coal Fly Ash Application

“…A low amount of hot-water soluble C with application of CFA reduced the amount of the C for microbial decomposition to produce CO 2 . Furthermore, the result of a previous study showed a low CO 2 and CH 4 production results from a reduction in the amount of hot-water soluble C in peatlands with CFA addition (Saidy et al, 2022).…”

“…This adsorbed organic C is resistant to microbial decomposition processes (Sowers et al, 2018;Liu et al, 2019). Prior examinations also showed that application of CFA reduces the substrate availability for microorganisms, therefore it produces low carbon mineralization in organic soils (Saidy et al, 2022) and mineral soils (Lim and Choi, 2014;Lim et al, 2017;Saidy et al, 2020).…”