As China struggles with feeding a growing population and an increasing middle class, the country has been stepping up its agricultural practices, including the use of nitrogen fertilizer to spur yields. However, a new study says the country could halve its current nitrogen fertilizer use without affecting yields and would decrease greenhouse gas emissions.
The new study was published this week in IOP Publishing’s Environmental Research Letters. The study showed that a 60 percent reduction in fertilizer use would significantly reduce emissions from areas that are “overly fertilized.”
China’s growing use of nitrogen fertilizer is believed to have dramatically increased its emissions of nitrous oxide (N2O). Since 2002, the warming effect from N2O emissions has outpaced the cooling effects from croplands storing carbon dioxide (CO2), according to the study.
Co-author of the study, Hanqin Tian, Ph.D., said, “Nitrogen fertilizer has become less efficient in recent years as the nitrogen input has surpassed nitrogen demands of plants and microbes. Excess nitrogen is not stimulating plant growth but leaving the system through leaching and nitrous gas emission.
“We need to advance education programs to inform Chinese farmers of both the economic and environmental costs of excessive nitrogen fertilizer use. Effective management practices, such as compound fertilizer use and optimized irrigation and tillage should be advanced to increase nitrogen use efficiency.”