This article is more than 10 years old

This article is more than 10 years old

Farmers' fields are a bigger source of water contamination in China than factory effluent, the Chinese government revealed today in its first census on pollution.

Senior officials said the disclosure, after a two-year study involving 570,000 people, would require a partial realignment of environmental policy from smoke stacks to chicken coops, cow sheds and fruit orchards.

Despite the sharp upward revision of figures on rural contamination, the government suggested the country's pollution problem may be close to - or even past - a peak. That claim is likely to prompt scepticism among environmental groups.

The release of the groundbreaking report was reportedly delayed by resistance from the agriculture ministry, which had previously insisted that farms contributed only a tiny fraction of pollution in China.

The census disproves these claims completely. According to the study, agriculture is responsible for 43.7% of the nation's chemical oxygen demand (the main measure of organic compounds in water), 67% of phosphorus and 57% of nitrogen discharges.

At the launch of the paper, Wang Yangliang of the ministry of agriculture recognised the fall-out from intensive farming methods.

"Fertilisers and pesticides have played an important role in enhancing productivity but in certain areas improper use has had a grave impact on the environment," he said. "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."

He said the ministry would introduce measures to improve the efficiency of pesticide and fertiliser use, to expand biogas generation from animal waste, and to change agricultural lifestyles to protect the environment.

While the high figure for rural pollution is partly explained by the immense size of China's agricultural sector, it also reflects the country's massive dependency on artificial farm inputs such as fertilisers.

The government says this is necessary because China uses only 7% of the world's land to feed 22% of the global population. An industrial lobby is pushing for even greater use of chemicals. It includes the huge power company CNOOC, which runs the country's largest nitrogen fertiliser factory in Hainan's Dongfang City.

But the returns on this chemical investment are poor. According to a recent Greenpeace report, the country consumes 35% of the world's nitrogen fertiliser, which wastes energy and other resources, while adding to water pollution and greenhouse gas emissions.

"Agricultural pollution has become one of China's gravest environmental crises," said Greenpeace campaign director Sze Pangcheung. "China needs to step up the fight against the overuse of fertilisers and pesticides and promote ecological agriculture which has obvious advantages for human heath, the environment, and sustainable development of agriculture."

Wen Tiejun, dean of the school of agriculture and rural development at Renmin university, said the survey should be used as a turning point. His research suggested that Chinese farmers used almost twice as much fertiliser as they needed.

"For almost all of China's 5,000-year history, agriculture had given our country a carbon-absorbing economy but in the past 40 years, agriculture has become one of the top pollution sources," he said. "Experience shows that we don't have to rely on chemical farming to resolve the food security issue. The government needs to foster low-pollution agriculture."

But in what appears to be a statistical sleight of hand, the government said the new agricultural data and other figures from the census would not be used to evaluate the success of its five-year plan to reduce pollution by 10%.

Zhang Lijun, the environmental protection vice-minister, claimed China was cleaning up its pollution problem far faster than other countries during their dirty stage of development.

"Because China follows a different pattern of development, it is very likely that pollution will peak when per capita income reaches US$3,000," he said, comparing this with the $8,000 he said was the norm in other nations.

If true, it would suggest the worst of China's pollution problems may already be over. According to the World Bank and International Monetary Fund, per capita incomes in China have already passed this point. If exchange rates and a low cost of living are factored in, Chinese incomes may be equivalent to more than $6,000.

But Zhang's claim is contestable. As countless pollution scandals have revealed, many industries and local governments routinely under-report emissions and waste.

Many harmful or controversial forms of pollution are either not measured - as is the case for carbon dioxide and small particle emissions - or the data is not made public, as is the case for ozone.

Zheng said the government would expand its monitoring system in the next five-year plan.

Extracts from China's first pollution report (for 2007):

• Sulphur dioxide emissions 23.2 million tonnes (91.3% from industry)

• Nitrogen oxide emissions: 18 million tonnes (30% from vehicles)

• Chemical oxygen demand discharges: 30.3 billion tonnes (44% from agriculture)

• Soot: 11.7 million tonnes.

• Solid waste: 3.8 billion tonnes (of which 45.7m tonnes is hazardous)

• Heavy metal discharges: 900 tonnes

• Livestock faeces: 243 million tonnes.

• Livestock urine: 163 million tonnes

• Plastic film on cropfields: 121,000 tonnes (80.3% recycled)