Spatial Analysis of Nitrogen and Phosphorus Loads from Non-Point Source in the Three Gorges Reservoir Area of Hubei

Abstract

Recently, increasing nutrient (i.e., nitrogen and phosphorus) concentrations have been observed in the surface water of many countries and the non-point source (NPS) pollution has become an important factor in the deterioration of water quality in the Three Gorges Reservoir Area (TGRA). The spatial and temporal analysis of NPS pollution loads in the TGRA of Hubei from 2005 to 2009 were estimated using export coefficient model in this paper. The results indicated the nutrient from rainfall was the dominant NPS of both TN and TP pollution. The spatial analysis of N and P loads from NPS in the TGRA of Hubei showed that the nutrient loads in BD County and YL District were higher than the other two counties in the study area. These findings demonstrate that the model could provide a simple and reliable approach to evaluate N and P loads to TGRA of Hubei and may be useful for planning and management of the local agricultural watersheds