More carbon per drop to enhance soil carbon sequestration in water-limited environments

Abstract

By storing carbon (C), soil provide natural solutions to climate change. However, implementing C sequestration practices on a large scale is complex because sequestration rates vary with climatic conditions, soil types and agricultural management. Researchers face challenges identifying effective C sequestration practices in arid and semi-arid regions because precipitation limits plant biomass production. We discuss the “more carbon per drop” approach to enhance C sequestration in a water-limited environment. This approach emphasizes increasing soil organic carbon (SOC) sequestration and reducing greenhouse gas emissions by enhancing water use efficiency and soil water storage. Agricultural strategies that increase the amount and diversity of C inputs, improve nutrient availability for crops, and minimize soil disturbance can simultaneously sequester soil C and enhance soil water storage. Strategies for enhancing SOC sequestration while increasing soil water storage could benefit farmers in arid and semi-arid regions because they can maintain a net-zero or net-negative C footprint. Therefore, implementing policies that promote SOC sequestration and soil water storage could provide natural climate solutions to the vast areas of the world facing water limitations. KEY POLICY HIGHLIGHTS SOC sequestration in a water-limited environment is challenging; more carbon per drop simultaneously increases SOC and soil water storage The social, economic, and cultural challenges of changing management practices for C sequestration could be addressed through a diverse set of incentives Incentivizing conventional SOC sequestration practices while investing in research and development of new frontier technologies could provide a win–win solution