Comprehensive government study shows agriculture to be the country’s biggest water polluter.
China’s government released its most in-depth domestic water pollution study Tuesday, showing discharges in 2007 to be twice as high as previous estimates, the New York Times reports.
This was the first time the Chinese government included agricultural effluent in the survey. Previously the Ministry of Environmental Protection calculated water pollution from a narrower list of sources that did not include fertilizers or pesticides, according to the NYT.
The two-year study analyzed 1.1 billion pieces of data from six million sources of pollution to create the most complete picture of China’s pollution problem to date. Sources surveyed included factories, farms, homes and pollution-treatment plants.
“Fertilizers and pesticides have played an important role in enhancing productivity but in certain areas improper use has had a grave impact on the environment,” said Wang Yangliang of the Ministry of Agriculture at a press conference for the study’s release, the Guardian reports.
“The fast development of livestock breeding and aquaculture has produced a lot of food but they are also major sources of pollution in our lives.”
The study showed that chemical oxygen demand-–a key pollution indicator-–more than doubled when farm runoff was taken into account. Agriculture contributes 43 percent of China’s chemical oxygen demand, 67 percent of phosphorus and 57 percent of nitrogen discharges, according to the study.
Sources inside the Chinese government said the report’s release was delayed by the agriculture ministry, which had insisted that farming contributed little pollution, according to the Guardian.
The study has provided a new perspective of water pollution in China. But old figures will still be used to evaluate the government’s success in meeting pollution targets, said Zhang Lijun, vice minister of environmental protection, according to the NYT.
“Current results of the census will not be linked to environmental performance,” he said at the press conference.
The Chinese government has a stated goal of reducing chemical oxygen demand by 10 percent between 2005 and 2010. Data from the study shows a decrease of 3 percent from 2006 to 2007, if agricultural effluent is excluded.
Reducing agricultural pollution will be difficult, says Ma Jun, director of the Beijing-based Institute of Public and Environmental Affairs.
“When it’s millions of farmers, it’s more difficult to bring it under control,” Ma told the NYT.
The government report supports the results of a study released earlier this year by Renmin University in China and Greenpeace, which found that Chinese farmers use 40 percent more fertilizer than necessary.
Read more about Chinese water issues in Circle of Blue’s special report Hidden Waters, Dragons in the Deep