Huangtang township which is located in the catchment of Tai Lake,Jiangsu Province and also a developed economic area was selected as a test area for this project.A dynamic monitoring and pre-warning system were set up for the project based on GIS.It supported by personal computer,peripherals like digitizer,plotter,printer,some software such as ARC/INFO,MAPINFO,FOXPRO,and prewarning models which was developed by author.Two temporal(1984 and 1994) informations of land use,soil fertility,soil and water resource pollution were chosen for database construction and dynamic analysis.Result of this project showed that in the area of developed economy just like Huangtang township,with developing rural industries and increasing population,the farmland resources and farmland area per capita are decreasing,the land area for civil use are increasing,and the environment of soil and surface water are suffering from industry and chemical fertilizer pollution.Meanwhile,applying a large quantity of chemical fertilizers to soil results in N,P,K unbalance.Some measures have been put forward for keeping the dynamic balance of the sum of farmland area.