Managing Global Resources for a Secure Future

Tribal and marginalised farmers on medium-upland and upland soils in eastern India rely on rainfed, rice-based cropping systems for food security. Farmers do not have a long-established history of rice production on these higher soils: they generally follow the traditional practice of puddled transplanted rice (PTR), which is common on nearby lowland soils and which is water-intensive. At higher elevations PTR is risky: in a separate study over a seven-year period encompassing typical climate variability, PTR was observed to be drought-affected in five years, including crop failure in three. Achieving food security, by reducing years of poor or no rice crop, is households’ primary production goal, followed by increasing cropping system productivity, water use efficiency and household nutrition. Aerobic direct seeded rice (ADSR), where rice is line sown by hand directly into fields and produced without the need for standing water through the growing season, reduces the rainfall-related production risks associated with PTR. ADSR, combined with shorter-duration varieties, can increase total annual cropping system productivity and diversity. We use the APSIM model to compare traditional and alternative rice-based production systems across two toposequences and three districts on the East India Plateau. Over 43 years (1971—2014) we compare the baseline PTR-fallow system to ADSR followed by a rabi (dry season) crop, in terms of system production and risk, and the amount of supplementary water required. PTR requires more water to produce a crop and thus carries higher risk in rainfed systems than alternative cropping system options. Results vary spatially and according to toposequence, both within single villages and across the eastern Indian landscape. This work is significant as it quantifies the value of cropping practices other than PTR to increase households’ food security and water use efficiency in variable and uncertain rainfall environments on challenging medium-upland and upland soils.