Methane Emission Dynamics in Organic and Conventional Rice Systems under Field Conditions

Abstract

Methane (CH₄) emissions sourced from irrigated rice fields were the significant contributor to agricultural greenhouse gas emissions due to anaerobic conditions created by continuous flooding irrigation system, which stimulate methanogenesis. Organic rice cultivation with intermittent irrigation has increasingly been considered as an alternative because it generally applies more efficient water management practices and ecological farming approaches. This study aims to analyze methane emission rates in organic and conventional rice systems at field scale as well as their impact of dynamic environmental parameters. Field observations were conducted in rice fields located in Pagerageung, Tasikmalaya in one crop season from August to November 2025. Methane gas was observed weekly with standard measurements as well as environmental parameters such as, soil electrical conductivity (EC), soil pH, soil temperature, soil moisture, and water level. Seasonal methane emissions from organic rice fields were recorded at 171.93 kg ha⁻¹ season⁻¹, while conventional produced 394.12 kg ha⁻¹ season⁻¹. This indicates that organic rice reduced methane emissions by approximately 56.4% compared to conventional practices. The substantial reduction highlights the effectiveness of organic management in mitigating methane emissions including its water management. Variations in methane emissions were also associated with changes in soil environmental conditions and water management during the cultivation period, underscoring the critical role of integrated soil and water management strategies in achieving low-emission and sustainable rice production systems.