No abstract

The AnnAGNPS model (Annualized Non-Point Source Pollution Model) is applied to analyze the spatial and temporal heterogeneity of agricultural non-point source pollutant loading in Zhangxi Watershed. The spatial database and attribute database of non-point source pollution is then established. Our result shows that in spatial scale, absorbed nitrogen has great spatial heterogeneity, while dissolved phosphorus's heterogeneity is relatively small. The pollutant loading in orchard and woodland is smaller than that in farmland; paddy soil's is larger compared to those in yellow and red soil. In temporal scale, over 55% of the pollutant loading happens in flood season. There is only 4% in dry season.