Effect of biochar and rice irrigartion methods on methane gas emissions

Abstract

Environmental problems related to agricultural production, especially rice, namely rice cultivation is the main cause of increasing global warming. The use of biochar types and types of irrigation can affect the rate of methane gas emission. The purpose of this research was to determine the effect of the treatment of addition of several types of biochar with a combination of irrigation treatment on the rate of methane gas emissions and investigate the rate of methane gas emissions at the time of collection in each phase of plant growth. The design used was a factorial Completely Randomized Block Design with the first factor was type of biochar: namely bamboo biochar by pyrolysis method, bamboo biochar by open firing method and coconut shellbiochar by open firing method, and the second factor was continuous flooding irrigation, macak-macak (0-0.5 cm water level) condition and intermittent with three replications. Soil sampling was carried out during the maximum tillering phase, the flower primordia phase and the grain filling phase. While gas sampling was carried outfive repetitions at intervals of 3 minutes. The results showed that the treatment of coconut shell biochar by open firing method combination with continuous flooding irrigation had the highest flux value of 11.44 × 10^-4 (mg/m²/min) at the time of taking 60 days after planting (dap). The number of tillers can affect the CH₄ flux value. The highest determination value is at the number of tillers 60 dap followed by 70 dap that is 57.05% and 28.77%, which means that the number of tillers has a significant effect on the CH₄ flux value.