Research on Relativity between Land Use Structure and Agricultural Non-Point Source Pollution in Upstream of Wenyu River

Based on the TM remote sensing image data and the field survey and county statistical data, this article researched the relativity between land use and agricultural non-point source pollution of four counties (Xiaotangshan, Shahe, Beiqijia and Houshayu) located in upstream of the Wenyu River by using export coefficient model. The results indicated that agricultural land had the biggest contribution on source of agricultural non-point pollution, next order was built-up land. The trend of pollution load of TN and TP from agricultural land decreased from1999 to 2005; while the trend of pollution load of TN and TP from built-up land were the contrary phenomena. From 1999 to 2005, the total trend of pollution load of TN and TP sourced by land use structure was decreased: the pollution load of TN was dropped from 1999 (253.74t per year) to 2005 (212.65t per year); pollution load of TP decreased from 1999 to 2005 were 15.13t per year and 9.11t per year, respectively. The pollution load of TN and TP had the unbalanced distribution among four counties, within; the Xiaotangshan County had the maximum pollution load of TN and TP.