A decade-long project engaging millions of farmers and agricultural researchers in China has helped reduce fertilizer use saving billions of dollars, increased crop yield, and reduced nitrogen pollution.
From 2005 to 2015, around 1,152 researchers reached out to more than 20.9 million small hold farmers in 452 counties to introduce best agricultural practices using locally available resources.
The research project led by Cui Zhenling from the China Agricultural University in Beijing along with 45 academicians resulted in reducing nitrogen fertilizer consumption by 14.7 to 18.1 percent.
Researchers applied an integrated soil crop management system (ISSM) saving 1.2 million tons of nitrogen fertilizers.
Despite a massive reduction in fertilizer use, "Average yields of maize, rice, and wheat increased by 10.8 to 11.5 percent, generating a net grain output of 33 million tons.
The increased grain output and decreased nitrogen fertilizer use were equivalent to 12.2 billion U.S. dollars," researchers maintained in the study titled "Pursuing sustainable productivity with millions of smallholder farmers."
During 13,123 field trials at maize, rice and wheat fields across the country, researchers tested how yields varied with different crop varieties, planting seasons, fertilizers and water usage. They also studied sunlight and its effect on the crop yield.
According to United Nation's Food and Agriculture Organization (FAO), the global consumption of the three main used fertilizers is forecast to grow annually with an average of between 1.5 and 2.4 percent respectively from 2015 to 2020 .
Excessive use of nitrogen fertilizer has led to massive soil acidification, a spike in water pollution and excessive greenhouse gas (GHG) emissions contributing to global climate change. As a result, water bodies including rivers and soil have seen the worst levels of pollution in the last few decades.
Researchers pointed out in China a farmer uses nearly 305 kg of nitrogen-based fertilizer while the global average is only 74 kg. "For a sustainable food-secure future, China needs a "great balancing act" to attain high yield and high efficiency with a substantially reduced environmental footprint," the study maintained.
China's effort to control nitrogen comes close on the heels of FAO's study warning Asian countries contribute nearly half of the global nitrogen pollution.
"Among the Asian countries, the bulk of the increase of world demand for nitrogen is expected to come from China (18 percent) and India (17 percent), followed by Indonesia (6 percent)," study claimed.
Efforts of researchers to train farmers reduce farming has also got crucial policy support. Chinese Premier, Li Keqiang in the work report to the first session of the 13th National People's Congress (NPC) announced to cut ammonia nitrogen emission by two percent. [Special coverage]
"This chemical oxygen demand and ammonia nitrogen emissions will be cut by two percent," he said.