Enhancing carbon sequestration potential of lowland rice agroecosystems for environmentally clean production system: A review

Abstract

Carbon (C) sequestration in soil has the potential to offset the negative impacts of natural and anthropogenic C emissions at the agroecosystem level, thereby contributing to the mitigation of climate change, while improving inherent soil productivity, quality and achieving environmentally clean production systems. Though rice is one of the most important staple food crops in the world, it is often criticized as the major contributor to methane emissions, thereby exacerbating global climate change. In tropical and sub-tropical regions, rice is mostly grown under submergence, which has implications for the turnover of active and passive C stores in the surface soil. Organic matter decomposition is slower under anaerobic conditions resulting in carbon stocks in anaerobic lowland rice fields that are 12%–58% higher than in upland aerobic rice soils. The aim of this article is to review the C sequestration potential in lowland rice system through modified agricultural management practices like integrated nutrient management, water management, organic farming, varietal selection, conservation agriculture, soil amelioration through biochar, rice intensification and mitigation of accelerated climate change. However, the effectiveness of soil C management strategies depends on crop management practices, climatic conditions, soil microbial diversity and activity, soil mineralogy and soil aggregation. This study highlights the importance of synergistic effects of multiple management practices in lowland rice agroecosystems, compares their efficiency, and examines the challenges involved and recommends various practices for environmentally clean production in lowland rice agroecosystems in the context of climate change.