![\"China\u2019s](\"https:\/\/dialogue.earth\/content\/uploads\/2021\/01\/history_graph_v4.svg\")
<\/div>China is the world\u2019s largest source<\/a> of agricultural greenhouse gases, emitting 830 million tonnes<\/a> of carbon dioxide-equivalent gases in 2014, the latest year for which official figures are available. This carbon footprint is equal to that of all the country\u2019s cars, planes and boats. Over one-quarter of the emissions from Chinese farms come from grass-chewing ruminants such as cows, goats and sheep.<\/p>\n\n\n\n Until now, China \u2014 like many countries \u2014 has focused its efforts to combat climate change on the energy and industrial sectors: subsidising<\/a> renewable energy, capping<\/a> coal consumption and controlling<\/a> industrial emissions. Emissions from agriculture have received far less attention.<\/p>\n\n\n\n But as China reaffirms its commitment to the Paris Agreement \u2013 with President Xi Jinping pledging in September that the country will reach peak carbon emissions<\/a> before 2030 and become carbon neutral before 2060 \u2013 farms could come under greater scrutiny.<\/p>\n\n\n\n Worldwide, agriculture is responsible for one-tenth<\/a> of the emissions that cause human-made global warming. The sector is also the largest source of greenhouse gases other than carbon dioxide, such as methane and nitrous oxide, which are 25 and 300 times more potent<\/a> at trapping heat respectively.<\/p>\n\n\n\n With Xi\u2019s pledge of carbon neutrality understood<\/a> to cover these non-carbon dioxide gases, figuring out how to get cows to burp less \u2013 among other measures to lower agriculture\u2019s carbon footprint \u2013 looks set to acquire national importance.<\/p>\n\n\n\n The researchers at the Shandong dairy farm hope a change in the cows\u2019 diet will make them less gaseous. For five months, they\u2019ve been tweaking the composition of the cattle feed, adding dietary supplements, and improving feed manufacturing techniques in an attempt to aid the cows\u2019 digestion.<\/p>\n\n\n\n \u201cMethane emissions are connected to dietary energy loss,\u201d says Diao Qiyu, the leader of the project and a professor at the Feed Research Institute under the Chinese Academy of Agricultural Sciences (CAAS). \u201cA higher feed utility rate and better metabolisation results in less methane production.\u201d<\/p>\n\n\n\n Finding the right feed will not only aid the climate, but also help Chinese livestock farms produce more meat and milk. As a by-product of the cows\u2019 digestion process, methane is a sign of inefficiency \u2013 up to 12% of bovine energy intake is estimated to be lost in the form of greenhouse gas excretions.<\/p>\n\n\n\n \u201cMethane itself is a waste of energy and pollutes the atmosphere,\u201d says Diao.<\/p>\n\n\n\n The prospect of making his farm more efficient convinced Tian Zhonghong, vice president of the dairy farm, Yinxiang Weiye, to greenlight Diao\u2019s project. \u201cI don\u2019t have strong feelings about climate change, melting ice caps or rising sea levels,\u201d he says. \u201cBut I believe waste has its value. Methane that\u2019s emitted into the air can have some use \u2013 that\u2019s why I\u2019m interested in their research.\u201d<\/p>\n\n\n\n The researchers chose to focus their project on dairy farms because they\u2019re more standardised than other Chinese livestock businesses. After tainted milk caused a major food safety scandal<\/a> in 2007, the government introduced a raft of regulations, which has also made the industry more suitable for experimentation, says Dong Lifeng, an associate professor involved in Diao\u2019s study.<\/p>\n\n\n\n Beef-producing farms are more numerous and thus the bigger climate threat. But they tend to be small-scale and use non-standardised methods, making it hard to conduct measurements, Dong adds. Overall, China has the world\u2019s fourth largest c attle herd, with 89 million animals<\/a>.<\/p>\n\n\n\n It\u2019s not just animals that are to blame for agriculture\u2019s climate footprint. China is the world\u2019s top rice-producing country, harvesting 209 million tonnes<\/a> of the grain in 2018. Rice is grown on paddies, fields flooded with a shallow layer of water. The more waterlogged the soil, the more microbes decompose organic matter, releasing methane. If there\u2019s too little water, however, yields suffer.<\/p>\n\n\n\n On the outskirts of Shanghai, Zhou Sheng, a professor at the Eco-environmental Protection Research Institute under the Shanghai Academy of Agricultural Sciences, leads a team of researchers studying rice paddy emissions.<\/p>\n\n\n\n When we visited their experimental field in early November, researchers were installing a transparent cube on a patch of soil that had been drained of water following the rice harvest the previous month. The device monitors methane emissions, absorbing air from the field and sealing samples inside small bags connected to the cube.<\/p>\n\n\n\n \u201cVarious changes could take place in farmland, which requires year-round monitoring and research,\u201d says Zhou. The researchers will analyse the air samples and collect data for computer models assessing agricultural greenhouse gas emissions.<\/p>\n\n\n\n Over the past decade, Zhou has researched several methods to control methane emissions from rice paddies. Carefully managing a rice paddy\u2019s irrigation time and water level can reduce emissions by 10-20%, he estimates. He\u2019s also working on a technique to convert rice straws \u2013 often burned or discarded<\/a> in rural China \u2013 into biochar. The charcoal-like substance can be used to store carbon in a stable form, and also applied to fields to improve soil quality and crop yields.<\/p>\n\n\n\n Another promising project Zhou is currently pursuing with another team of Shanghai researchers involves creating a new drought-resistant strain of rice. Because paddies using the grain require little water for irrigation, they produce up to 90% fewer methane emissions, Zhou says.<\/p>\n\n\n\n The new rice variety is currently being promoted in the eastern provinces of Anhui and Jiangxi, and Zhou believes it could offer a green solution to farms across China. Researchers are now working to raise the rice\u2019s quality and yields.<\/p>\n\n\n\n Convincing farmers to adopt emission-reduction techniques, however, is a challenge. This is one reason Zhou is excited about the new rice variety: it doesn\u2019t cost the farmers much to implement.<\/p>\n\n\n\n \u201cIt\u2019s impossible for farmers to precisely control water levels and it\u2019s too costly to introduce automatic systems,\u201d says Zhou. \u201cIf the technology is too advanced, the cost and maintenance becomes a problem. But if it\u2019s too simple, it might not be effective enough.\u201d<\/p>\n\n\n\n Despite these efforts by China\u2019s scientists, the country\u2019s government doesn\u2019t seem to be prioritising the reduction of agriculture\u2019s climate impact: it has set no emission targets for the sector. Food security remains paramount.<\/p>\n\n\n\n \u201cThe most important thing is that everyone gets sufficient food,\u201d says Li Yu\u2019e, a researcher at CAAS and one of China\u2019s top experts on agricultural greenhouse gas emissions. \u201cIf [a measure cutting emissions] reduces food production, it won\u2019t be considered a real solution.\u201d<\/p>\n\n\n\n Experts recognise there\u2019s still a long way to go before any new emission-reduction techniques can be implemented nationwide. Many questions remain unanswered, including how the new solutions will be promoted among rural communities, how they\u2019ll be implemented and made cost-effective, and who will pay for them.<\/p>\n\n\n\n \u201cThe economic benefit of agricultural emissions reduction is a main concern,\u201d says Cai Zucong, professor of soil science at Nanjing Normal University. \u201cThere has been a lot of research, but the problem is in the application. Who should pay for the cost? Farmers will only do it if there\u2019s a benefit.\u201d<\/p>\n\n\n\n Another problem is that many rural areas simply lack the workforce. Cutting agricultural emissions requires precise management, but many Chinese farmers let their paddy fields lie fallow in the winter to go and work in the cities. As a result, the farmland is left soaked in water and releases large amounts of methane, says Cai.<\/p>\n\n\n\n But Michael Clark, food systems researcher and James Martin Fellow at the Oxford Martin School and the Nuffield Department of Population Health, doesn\u2019t think humanity can afford to compromise on efforts to reduce emissions. The result of not addressing climate change now, he says, is that in a few decades\u2019 time \u201cwe [won\u2019t be able to] grow the crops that we\u2019ll want to because the climate isn\u2019t suitable for them anymore\u201d.<\/p>\n\n\n\n Even if all other sectors brought their greenhouse gas emissions down to zero immediately, global agriculture\u2019s carbon footprint is big enough to inhibit the Paris Agreement\u2019s target of limiting warming to 1.5C, according to a paper<\/a> Clark co-authored, published November in the academic journal Science.<\/p>\n\n\n\n \u201cI think it\u2019s pretty urgent that we do need to start thinking about changes to food systems,\u201d he says. \u201cIt\u2019s like the saying on planting a tree. The best time to do it was 20 years ago. The second-best time is today.\u201d<\/p>\n\n\n\n Despite their alarming call for action, Clark and his co-authors also offered several strategies for lowering emissions. They even predicted that, in the best-case scenario, these strategies could lead to negative emissions, whereby agriculture absorbs more carbon dioxide than it emits in equivalent gases.<\/p>\n\n\n\n \u201cWe\u2019re basically going to have to do just about everything that we know,\u201d Clark says. \u201cAnd we might have to do more.\u201d He points to large-scale field trials<\/a> conducted in China between 2005 and 2015 that showed how improved farming methods can reduce greenhouse gas emissions by over one-fifth, depending on the crop.<\/p>\n\n\n\n China has already made some progress on issues such as nitrogen fertilizer overuse. The country currently accounts for 30% of global fertilizer consumption, as Chinese farmers tend to use massive amounts on their fields to boost crop yields. These fertilizers cause run-offs that affect water quality<\/a>, and also lead to soil microbes emitting nitrous oxide, which accounts for 34% of China\u2019s agricultural carbon dioxide-equivalent emissions.<\/p>\n\n\n\n The Chinese government did commit to controlling methane emissions from paddy fields and nitrous oxide released from farmland in its Nationally Determined Contributions submitted<\/a> in 2015 as part of the Paris climate talks. And while there has been little movement on the methane front, China\u2019s fertilizer usage volume and intensity have both been declining<\/a> since that year.<\/p>\n\n\n\n Zhou, the rice paddy researcher, hopes President Xi\u2019s climate pledge will bring new impetus to efforts to cut farm emissions. \u201cI\u2019m still optimistic about the future,\u201d he says.<\/p>\n\n\n\n Researchers suggest carbon trading \u2013 systems where polluting companies can offset their emissions by paying for reductions elsewhere \u2013 could offer a way to accelerate the rollout of effective agricultural emission-reduction techniques. Such methods would have to be officially recognised as tradable carbon reduction credits.<\/p>\n\n\n\n The challenge, however, will be how to integrate China\u2019s farms into a carbon trading system. Unlike industrial sectors \u2013 where emissions are concentrated and easier to track \u2013 agricultural greenhouse gases are diffuse, emanating from large tracts of land. This is especially true when it comes to emissions from paddy fields, as growers are mostly smallholder farmers whose paddies add up to nearly 300,000 square kilometres \u2013 about half the size of France.<\/p>\n\n\n\n A possible solution would be ensuring that county governments, rather than individual farmers, are made responsible for reducing emissions under any carbon trading system, Zhou suggests. That way, it will be much easier to assign responsibility for emissions.<\/p>\n\n\n\n Currently, China\u2019s emission trading scheme only covers the power sector. Agricultural emission reduction projects certified under China\u2019s offset mechanism \u2013 the Chinese Certified Emission Reduction scheme \u2013 can produce credits to offset carbon emissions voluntarily.<\/p>\n\n\n\n![\"Main](\"https:\/\/dialogue.earth\/content\/uploads\/2021\/01\/composition_graph_eng_v4.svg\")
<\/div>![\"monitoring](\"https:\/\/dialogue.earth\/content\/uploads\/2021\/01\/14A6177-scaled.jpg\")
<\/div>Reducing emissions from paddy fields<\/h2>\n\n\n\n
![\"setting](\"https:\/\/dialogue.earth\/content\/uploads\/2021\/01\/14A6256-scaled.jpg\")
<\/div>![\"This](\"https:\/\/dialogue.earth\/content\/uploads\/2021\/01\/14A6254-scaled.jpg\")
<\/div>Food security still a priority<\/h2>\n\n\n\n
![\"Cows](\"https:\/\/dialogue.earth\/content\/uploads\/2021\/01\/14A6045-scaled.jpg\")
<\/div>Carbon trading for agriculture?<\/h2>\n\n\n\n
![\"Calves](\"https:\/\/dialogue.earth\/content\/uploads\/2021\/01\/14A6073-scaled.jpg\")
<\/div>