Alternatives to burning can increase Indian farmers’ profits and cut pollution, new study shows
Published in Science, the study provides evidence for national policies that block stubble burning and promote no-till mechanization to manage crop residues. The economic study (by P. Shyamsundar, N. P. Springer, H. Tallis, S. Polasky, M. L. Jat, H. S. Sidhu, P. P. Krishnapriya, N. Skiba, W. Ginn, V. Ah)shows that thousands of farmers in northern India could increase their profits if they stop burning their rice straw and adopt no-till practices to grow wheat. Alternative farming practices could also cut farmers’ greenhouse gas emissions from on-farm activities by as much as 78% and help lower air pollution in cities like New Delhi.
The study compares the costs and benefits of 10 distinct land preparation and sowing practices for northern India’s rice-wheat cropping rotations, which are spread across more than 4 million hectares. The direct seeding of wheat into unploughed soil and shredded rice residues was the best option — it raises farmers’ profits through higher yields and savings in labour, fuel, and machinery costs.
Win-win
The Science study demonstrates that it is possible to reduce air pollution and greenhouse gas emissions in a way that is profitable to farmers and scalable.
Farmers have alternatives, the study shows. To sow wheat directly without ploughing or burning rice straw, farmers need to purchase or rent a tractor-mounted implement known as the “Happy Seeder,” as well as attach straw shedders to their rice harvesters. Leaving straw on the soil as a mulch helps capture and retain moisture and also improves soil quality, according to M.L. Jat, CIMMYT Principal Scientist, cropping systems specialist and a co-author of the study.
A burning issue
To quickly and cheaply clear their fields to sow wheat each year, farmers in northern India burn an estimated 23 million tons of straw from their rice harvests. Regulations are in place in India to reduce agricultural fires but burning continues because of implementation challenges and lack of clarity about the profitability of alternate, no-burn farming. In November 2017, more than 4,000 schools closed in Delhi due to seasonal smog. This smog increases during October and November when fields are burned. It causes major transportation disruptions and poses health risks across northern India, including Delhi, a city of more than 18 million people. Some of these problems can be resolved by the use of direct sowing technologies in northwestern India.
