Agriculture is the main cause of water pollution in China, according to the country’s first national census of pollution sources. The discharge of Chemical Oxygen Demand (COD), a major water pollution indicator, totalled about 30m tonnes in 2007, 43 per cent of which came from agricultural sources, according to the census.

Zhang Lijun, vice minister of environmental protection, was reported by Xinhua as saying that controlling pollution from agriculture is essential to solving the water pollution problem. Livestock and poultry are the main sources of agricultural pollution, said Wang Yanliang from the Ministry of Agriculture. He went on to say that the ministry would work to help more livestock and poultry-breeding farms develop methane digesters. Measures will also be taken to limit rural waste discharge and improve the efficiency of agriculture chemicals.

Industrial pollutant discharges are mainly concentrated in a small number of industries and areas that have particular structural problems.

This census is the first significant survey on national pollution. Environmental experts have said that reliable statistics on the sources and extent of pollution are essential in order to tackle the problem.