Notice of RetractionStudy of Agricultural Non-Point Source Pollution of Yongding River Based on Export Coefficient Model

Comparing with point source pollution, the non-point source (NPS) one, particularly from agricultural activities, has been dominant in many countries presently, causing nutrient loss, aqueous systems damaging, and eutrophication. One of the key elements responsible for it is nitrogen (N). The Yongding River is an important watershed in North China, which relates to Beijing City (capital of China), Tianjing City and Hebei, Inner Mongolia, Shanxi province. This study, reveals agricultural NPS pollution of Yongding River in Hebei province. The resource, loading and distribution of agricultural NPS pollution are simulated and analyzed in the paper based on remoting sense and geographic information system by export coefficient model (ECM). The result indicates that the total NPS-N loading of the research area was 5.68 × 104 t in 2008. The loading of agricultural landuse was 4.38 × 104 t, and that of rural life and livestock feeding was 0.90 × 104 t and 0.40 × 104 t respectively. As far as the spacial distribution of the loading is concerned, farm lands (sloping areas especially), villages and hoggeries were areas with heavy pollution. In the conclusion, it is suggested that the methods of agricultural landuse and N fertilizer utilization should be improved as well as the treatment efficiency of waster water and solid waste should be increased.