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The wetland are closely linked with humanity’s survival, the multiplication, the development, it is not only to provide many kinds of resources for the humanity, but also has tremendous environmental functions and benefits, known as "kidney of the earth". However, the wetland withers day by day, the survival of the human environment is under threat. In order to protect the wetland, the primary solution question is the wetland dynamic monitor and the change driving forces analysis.Based on the country special supported, "China’s offshore marine comprehensive survey and evaluation" (Project 908) satellite remote sensing survey of Shandong and Jiangsu islands and coastal zone, The paper has carried out wetland dynamic monitor research and its change driving forces analysis in Sheyang County, Yancheng City, Jiangsu Province. Among the main tasks include:1. Integrated application of maximum likelihood and decision-Tree methods, obtained two wetland thematic maps of 1992 and 2002. Among them, for serious ground objects mixing with maximum likelihood method, based on the coastal zone wetland’s spatial distribution rule, established two kinds of levels-distance to coastline layer and distance to river layer, trained the ground object classification rule using decision tree, finally, modified the supervised classification result. Above method reduced ground objects mixing caused by "different objects with the same spectrum" , overall classification accuracy achieved 81%.2. By analysing the dynamic change between 1992 and 2002 image classification result, obtained various ground objects mutual transformation. Finding that the general trend of wetland change is the degeneration: the natural wetland transforms to the artificial wetland and the non-wetland, and the artificial wetland transforms to non-wetland. Mainly analyzes: (1) wetland to the non-wetland’s transformation, its transformed area is 10421.87 hectares, the conversion rate was 17.73 percent ; (2) mutual transformation of wetland, among them the natural wetland to the artificial wetland’s transformed area is 8143.65 hectares, its conversion rate is 23.26 percent, the main transform is reed, salt vegetation and fish ponds to the nude beach, the transform area respectively is 1875.06 hectare, 1874.61 hectares and 4568.4 hectares, and the conversion rate respectively is 15.06 percent, 22.61 percent and 45.58 percent; (2) Transform between artificial wetlands, the area from saltern to fishpound is 2740.95 hectares, and the conversion rate is 39.34 percent.3. Based on the wetland dynamic monitoring result, Combined with 1992 and 2002 Sheyang County economic statistical data and field datas, analyzed the wetland change driving forces. Found that the main driving force of Sheyang County wetland change is the economic factors. Finally, based on the present situation of Sheyang wetland change and the driving force, brought forward five suggestions of Sheyang country wetland Exploitation, Utilization and protection.
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