Abstract: With soil loss equation and GIS platform, the nitrogen load from rural non-point sources was estimated by a combination of field experiments and survey in Dapu Town, Yixin City, Jiangsu Province. Results showed that the nonpoint discharge of nitrogen from Dapu Town were about 207.0 t·a^-1, which was composed of 80.6 tons of farmland, 61.1 tons of living sewage, 49.3 tons of fishery, 10.5 tons of garbage and 5.4 tons of sediment production per year, which occupied 39.0%, 29.5%, 23.8%, 5.1% and 2.6%, respectively. The critical control factors of the five nitrogen sources were farmland, living sewage and fishery. The average nitrogen discharge from four villages, Fangqiang, Dapu, ubei and Punan, were 80.4, 73.0, 60.4 and 52.3 kg·hm^-2·a^-1, which were much higher than that from other villages. Therefore the four villages were critical control areas.

Key words: Western Liaoning area, Plantation, Climatic productivity