Posts Tagged ‘Greenhouse gas emissions’

Alternatives to burning can increase Indian farmers’ profits and cut pollution, new study shows

Published in Science, the article provides evidence for national policies that block stubble burning and promote no-till mechanization to manage crop residues.

This story by Mike Listman was originally posted on the website of the International Maize and Wheat Improvement Center (CIMMYT).

India’s farmers feed millions of people. (Photo: Dakshinamurthy Vedachalam)

The new 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 unplowed soil and shredded rice residues was the best option — it raises farmers’ profits through higher yields and savings in labor, fuel, and machinery costs.

The study, conducted by a global team of eminent agriculture and environmental scientists, was led by researchers from The Nature Conservancy, the International Maize and Wheat Improvement Center (CIMMYT), the Indian Council of Agricultural Research (ICAR), the Borlaug Institute for South Asia (BISA) and the University of Minnesota.

A new economic study in the journal Science 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.

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. That enormous mass of straw, if packed into 20-kilogram 38-centimeter-high bales and piled on top of each other, would reach a height of over 430,000 kilometers — about 1.1 times the distance to the moon.

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.

Farmers have alternatives, the study shows. To sow wheat directly without plowing or burning rice straw, farmers need to purchase or rent a tractor-mounted implement known as the “Happy Seeder,” as well as attach straw shredders 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 combine harvester (left) equipped with the Super Straw Management System, or Super SMS, works alongside a tractor fitted with a Happy Seeder. (Photo: Sonalika Tractors)

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.

The paper shows that Happy Seeder-based systems are on average 10%–20% more profitable than straw burning options.

“Our study dovetails with 2018 policies put in place by the government of India to stop farmers from burning, which includes a US$166 million subsidy to promote mechanization to manage crop residues within fields,” said Priya Shyamsundar, Lead Economist, Global Science, of The Nature Conservancy and first author of the study.

Shyamsundar noted that relatively few Indian farmers currently sow their wheat using the Happy Seeder but manufacturing of the Seeder had increased in recent years. “Less than a quarter of the total subsidy would pay for widespread adoption of the Happy Seeder, if aided by government and NGO support to build farmer awareness and impede burning.”

“With a rising population of 1.6 billion people, South Asia hosts 40% of the world’s poor and malnourished on just 2.4% of its land,” said Jat, who recently received India’s prestigious Rafi Ahmed Kidwai Award for outstanding and impact-oriented research contributions in natural resource management and agricultural engineering. “Better practices can help farmers adapt to warmer winters and extreme, erratic weather events such as droughts and floods, which are having a terrible impact on agriculture and livelihoods. In addition, India’s efforts to transition to more sustainable, less polluting farming practices can provide lessons for other countries facing similar risks and challenges.”

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.

“Within one year of our dedicated action using about US$75 million under the Central Sector Scheme on ‘Promotion of agriculture mechanization for in-situ management of crop residue in the states of Punjab, Haryana, Uttar Pradesh and NCT of Delhi,’ we could reach 0.8 million hectares of adoption of Happy Seeder/zero tillage technology in the northwestern states of India,” said Trilochan Mohapatra, director general of the Indian Council of Agricultural Research (ICAR). “Considering the findings of the Science article as well as reports from thousands of participatory validation trials, our efforts have resulted in an additional direct farmer benefit of US$131 million, compared to a burning option,” explained Mohapatra, who is also secretary of India’s Department of Agricultural Research and Education.

Read the full study in Science

This research was supported by the Susan and Craig McCaw Foundation, the Institute on the Environment at the University of Minnesota, the CGIAR Research Program on Wheat (WHEAT), and the CGIAR Research Program on Climate Change, Agriculture and Food Security (CCAFS). The Happy Seeder was originally developed through a project from the Australian Centre for International Agricultural Research (ACIAR).

For more information, or to arrange interviews with the researchers, please contact:

Rodrigo Ordóñez, Communications Manager, CIMMYT
r.ordonez@cgiar.org, +52 5558042004 ext. 1167


Farmers, environment, and carbon markets to profit from more precise fertilizer management, study shows

A wheat farm family from the Yaqui Valley, northwestern Mexico. Photo: CIMMYT/Peter Lowe

EL BATÁN, MEXICO – 24 APRIL 2018–Farmers of irrigated wheat can increase profits and radically reduce greenhouse gas emissions by applying fertilizer in more precise dosages, according to a new study.

Published today in the journal Agriculture, Ecosystems and Environment, the study shows that farmers in the Yaqui Valley, a major breadbasket region in northwestern Mexico that covers over 1.5 times the area of the Mexico City, are applying significantly more nitrogen fertilizer than they need to maximize wheat yields.

Lower application of nitrogen fertilizer would cut the region’s yearly emissions of nitrous oxide, a potent greenhouse gas, by the equivalent of as much as 130,000 tons of carbon dioxide, equal to the emissions of 14 million gallons of gasoline, according to Neville Millar, a senior researcher at Michigan State University (MSU) and first author of the published paper.

“Our study is the first to isolate the effect of multiple nitrogen fertilizer rates on nitrous oxide emissions in wheat in the tropics or sub-tropics,” Millar said. “It shows that applying fertilizer to wheat at higher than optimal economic rates results in an exponential increase in nitrous oxide emissions.”

Yaqui Valley wheat farming conditions and practices are similar to those of huge wheat cropping expanses in China, India, and Pakistan, which together account for roughly half of worldwide nitrogen fertilizer use for wheat, according to study co-author Iván Ortíz-Monasterio, a wheat agronomist at the International Maize and Wheat Improvement Center (CIMMYT), whose Yaqui Valley experiment station was the site of the reported research.

“The recommendations are thus globally relevant and represent a potential triple win, in the form of reduced greenhouse gas emissions, higher income for farmers and continued high productivity for wheat cropping,” Ortíz-Monasterio said.

Measuring nitrous oxide after nitrogen fertilizer applications in spring durum wheat crops during two growing seasons, Millar and an international team of scientists found an exponential increase in emissions from plots fertilized at greater than economically-optimal rates—that is, when the extra nitrogen applied no longer boosts grain yield.

They also found that grain quality at the economically optimal N rates was not impacted and exceeded that required by local farmer associations for sale to the market. They examined five different nitrogen fertilizer dosages ranging from 0 to 280 kilograms per hectare.

“In our study, the highest dosage to get optimum wheat yields was 145 kilograms of nitrogen fertilizer per hectare in the 2014 crop,” said Millar. “Yaqui Valley farmers typically apply around 300 kilograms. The wheat crop takes up and uses only about a third of that nitrogen; the remainder may be lost to the atmosphere as gases, including nitrous oxide, and to groundwater as nitrate.”

Promoting profitable, climate-friendly fertilizer use

Farmers’ excessive use of fertilizer is driven largely by risk aversion and economic concerns, according to Ortíz-Monasterio. “Because crops in high-yielding years will require more nitrogen than in low-yielding years, farmers tend to be optimistic and fertilize for high-yielding years,” said Ortíz-Monasterio. “At the same time, since farmers don’t have data about available nitrogen in their fields, they tend to over-apply fertilizer because this is less costly than growing a crop that lacks the nitrogen to develop and yield near to full potential.”

Ortíz-Monasterio and his partners have been studying and promoting management practices to help farmers to use fertilizer more efficiently and take into account available soil nitrogen and weather. This technology, including Greenseeker, a handheld device that assesses plant nitrogen needs, was tested in a separate study for its ability to advise farmers on optimal rates of fertilizer use.

“Sensing devices similar to Greenseeker but mounted on drones are providing recommendations to Yaqui Valley farmers for wheat crops grown on more than 1,000 acres in 2017 and 2018,” Ortiz-Monasterio notes.

Part of a research partnership between CIMMYT and MSU’s W.K. Kellogg Biological Station (KBS) Long-Term Ecological Research program to reduce greenhouse gas impacts of intensive farming, a key aim of the present study was to generate new emission factors for Mexican grain crops that accurately reflect nitrous oxide emissions and emission reductions and can be used in global carbon markets, according to Millar.

“The emission calculations from our work can be incorporated by carbon market organizations into carbon market protocols, to help compensate farmers for reducing their fertilizer use,” he said.

“This study shows that low emissions nitrogen management is possible in tropical cereal crop systems and provides important guidance on the optimal levels for large cropping areas of the world,” said Lini Wollenberg, an expert in low-emissions agriculture for the CGIAR Research Program on Climate Change, Agriculture and Food Security (CCAFS), which helped fund the research. “With these improved emission factors, countries will be able to better plan and implement their commitments to reducing emissions.

To view the article

Millar, N., A. Urrea, K. Kahmark, I. Shcherbak, G. P. Robertson, and I. Ortiz-Monasterio. 2018. Nitrous oxide (N2O) flux responds exponentially to nitrogen fertilizer in irrigated wheat in the Yaqui Valley, Mexico. Agriculture, Ecosystems and Environment, https://doi.org/10.1016/j.agee.2018.04.003.

KBS LTER
Michigan State University’s Kellogg Biological Station Long-term Ecological Research (KBS LTER) Program studies the ecology of intensive field crop ecosystems as part of a national network of LTER sites established by the National Science Foundation. More information at https://lter.kbs.msu.edu

MSU AgBioResearch
MSU AgBioResearch engages in innovative, leading-edge research that combines scientific expertise with practical experience to help advance FOOD, ENERGY and the ENVIRONMENT. It encompasses the work of more than 300 scientists in seven MSU colleges — Agriculture and Natural Resources, Arts and Letters, Communication Arts and Sciences, Engineering, Natural Science, Social Science and Veterinary Medicine — and includes a network of 13 outlying research centers across Michigan.

CIMMYT
The International Maize and Wheat Improvement Center (CIMMYT) is the global leader in publicly-funded maize and wheat research and related farming systems. Headquartered near Mexico City, CIMMYT works with hundreds of partners throughout the developing world to sustainably increase the productivity of maize and wheat cropping systems, thus improving global food security and reducing poverty. CIMMYT is a member of the CGIAR System and leads the CGIAR Research Programs on Maize and Wheat and the Excellence in Breeding Platform. The Center receives support from national governments, foundations, development banks and other public and private agencies. For more information, visit www.cimmyt.org.

CCAFS
The CGIAR Research Program on Climate Change, Agriculture and Food Security (CCAFS), led by the International Center for Tropical Agriculture (CIAT), brings together some of the world’s best researchers in agricultural science, development research, climate science and earth system science to identify and address the most important interactions, synergies and tradeoffs between climate change, agriculture and food security. CCAFS is carried out with support from CGIAR Fund Donors and through bilateral funding agreements. www.ccafs.cgiar.org