9Ongley E D, Zhang Xiaolan, Yu Tao. Current status of agricultural and rural non-point source Pollution assess- ment in China[J]. Environment Pullution, 2010, 158 (5) : 1159-1168.
10Weld J L, Parsons R L, Beelgle D B. Evaluation of phosphorus based nutrient management strategies in Pennsylvania[J]. Journal of Soil and Water Conserva- tion, 2002,57(6) :448-454.