Abstract:

Planting is one of the main pollution sources of Yanqing County, where located Guanting Reservoir, the strategic water resource of Beijing. In order to control agricultural non-point source pollution and ensure the safe of water resource field, it is necessary to learn the pollution status. Survey methods were applied to find out the Planting source of Yanqing County in 2007, and analyze the chemical farming inputs (fertilizers, chemical pesticides and plastic film) as well as wastage (crop straw) production utilization. The overall pollution was evaluated on the basis of survey. The results showed that, the total amount of fertilizer application of Yanqing County was 16169.72 tons (pure), in which nitrogen fertilizers was 11408.88 tons, accounting for 70.6%. The total nitrogen (TN) loss of Planting accounted for 52.4% of total nitrogen emissions, which is the serious source of nitrogen emission. Phosphorus loss accounted for 35.1% of total amount. Artificial herbicide-Atrazine is more prominent pesticides, application rate was 28,129.97 kg per year. Seven towns (Kangzhuang, Yanqingzhen, Zhangshanying, Jiuxian, Yongning, Xiangying, Jingzhuang) are the key emission sources, which neighbored to the Guanting Reservoir, become key threats to water quality. Finally, four control measures were proposed from three levels of the source block, process control and end treatments according to the types and causes of the main sources.