Nitrogen Non-point Field Pollution in China:IRegionalization of Pollution Types and Pollution Analysis in Different Provinces

After summarizing studies about nitrogen fertilizer non-point pollution in China, the type of nitrogen non-point field pollution was regionalized. There were twelve first-types of nitrogen fertilizer non-point pollution, which could be incorporated to three types. Calculation of nitrogen pollution index was defined, based on which, pollution status in different provinces were analysised with the statistic data of nitrogen fertilizer usage in different provinces.