Influence of biochar application on carbon dioxide (CO2) emission under soybean crop

Abstract

Biochar, an organic solid produced through pyrolysis, exhibits promising potential as a soil amendment. The utilization of biochar as a soil amendment is geared towards the reduction of CO2 emissions and the sequestration of carbon in soil, thus playing a pivotal role in addressing climate change. This research was undertaken to quantify the extent of carbon emissions resulting from various biochar application treatments in soybean cultivation. The field study was structured in a randomized non-factorial design, encompassing five distinct biochar types: rice husk at application rates of 20 and 30 ton ha-1, pulai wood (Alstonia scholaris) at rates of 20 and 30 ton ha-1, and a control group serving as a reference. Each treatment was replicated three times. The quantification of greenhouse gas emissions involved the utilization of a CO2 gas detector (Digital type HT-2000) placed within a chamber measuring 66 cm x 46 cm x 78 cm. The findings elucidated that the application of biochar had a discernible influence on the levels of CO2 gas emissions. Specifically, the application of 30 ton ha-1 of rice husk and 20 ton ha-1 of pulai wood yielded higher emissions in comparison to the control group. This phenomenon is attributed to the favorable environment created by biochar within wetter soil conditions, fostering the proliferation of microorganisms, and subsequently contributing to increased emissions through microbial respiration.