Ahmedabad: One crop shift could tackle three farm pressures at once. Reducing rice cultivation in water-stressed districts could lower fertiliser use, groundwater extraction and methane emissions, according to a study by IIT Gandhinagar and Germany’s Helmholtz Centre for Environmental Research (UFZ).The reasoning is physical. Paddy rice, the crop the model contracts most, is simultaneously the most water-hungry, the most fertilised, and the largest methane source in Indian agriculture. Cutting rice area in over-stressed districts pulls all three pressures down together, said researchers.Published recently in Nature Communications journal, the study by Prof Udit Bhatia and Dr Shekhar Sharan Goyal from IIT-Gn and Dr Rohini Kumar from UFZ examined crop patterns across 664 districts. It suggested shifting a part of the area under rice and wheat to maize, jowar, bajra and ragi. The researchers said the changes could reduce nitrogen surplus — the fertiliser left unused by crops — and lower water consumption without affecting calorie production or farmers’ overall returns.“Indian agriculture pulls two emergency levers at the same time: too much fertiliser and too much groundwater. We have been trying to fix this one at a time,” said Prof Udit Bhatia of IIT Gandhinagar. “What this analysis shows is that there is a single lever, nitrogen surplus, that meaningfully moves both. When we optimise for nitrogen surplus, water savings follow on their own.”The team’s optimisation model reallocated existing cereal area across the 664 districts among six grains — rice, wheat, maize, sorghum (jowar), pearl millet (bajra), and finger millet (ragi) — under strict rules: no state could fall below its 2017 calorie production, the cereal sector’s net returns had to hold at 2017 levels, and a crop could only expand where it had a documented cultivation history.In the recommended pattern, rice area contracts by 8.8% and wheat by 12.1%. The freed land is taken up by maize and three traditional millets (jowar, bajra and ragi) whose combined share of cereal cropland rises from about a quarter to nearly a third.Crucially, the study does not call for replacing rice or wheat. It reallocates land at the margin, preserving existing cultivation and diets while making room for coarse cereals where they can grow well.The point is about growing the right crop in the right place, and pairing any push toward coarse cereals with the markets and support that let farmers make that choice without losing income, said researchers.
