Nearly 21 million farmers in 452 counties across China have adopted recommendations from scientists in a 10-year agriculture sustainability study to reduce fertilizer use. According to Nature, their efforts are paying off: all told, the farmers are now $12.2 billion better off than they were before.

China, Yunnan province, southern China, farming, subsistence farming, agriculture

46 scientists, led by Cui Zhenling of China Agricultural University, were part of the landmark study aiming to cut fertilizer use. Chinese farmers use around four times the global average of nitrogen without lowering yields, which has myriad environmental consequences. The researchers conducted 13,123 field studies between 2005 and 2015 all across China at wheat, rice, and corn farms, testing “how yields varied with different crop varieties, planing times, planing densities, fertilizer, and water use. They also measured sunlight and the effect of the climate on farm production,” according to Nature.

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The scientists came up with tailored advice for farmers depending on conditions in their location. Nature gave northeast China rice farms as an example: there the researchers suggested farmers cut overall nitrogen use by around 20 percent. They said farmers could plant seeds closer together and increase nitrogen applied late in a growing season.

Between 2006 and 2015, millions of farmers adopted the suggestions, and the scientists held around 14,000 workshops and outreach programs. Cui said, “The [farmers] were skeptical, but we gained their trust, and then they depended on us — that was our greatest reward.” That trust seemed to pay off: according to the China Agricultural University’s press release, the practices “increased grain production by 33 million tons, reduced nitrogen fertilizer use by 1.2 million tons, and increased income by 79.3 billion yuan.”

Some researchers think the lessons learned in the $54 million project may not translate easily in other countries. University of Leeds scientist Leslie Firbank told Nature, “It would clearly have benefits across sub-Saharan Africa, but an approach is needed that crosses borders, organizations, and funders.”

Nature published the study online earlier in March.

+ Nature

+ China Agricultural University

Via Nature News

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