Dynamic analysis of the wetland resource changes in the estuary of the pearl river delta using remote sensing

The Pearl River Estuary wetland in the developed region was selected as the studying object in this thesis. The integrated approach including the remote sensing and geography information system (GIS), the field survey, and collecting history data was adopted to analyze the spatio-temporal evolution in recent twenty years. In the wetland classification of east and west shore of inner Lingding ocean, taking ERD AS software as the flat roof, gradation and classification method based-on knowledge were adopted. The main conclusions were summed up as following: (1) It is a great advantage to study the wetland landscape evolution using remote sensing and GIS in the regional scale of the Pearl River Estuary. The gradation and classification method based-on knowledge can overcome the shortage of human-computer alternation translation with eyes, realize the goal of classification for great region and the more temporal images, and also fulfill the landscape mapping. In this paper, the total classification resolution reaches 85 percent, the coefficient of kappa exceeds 0.8. (2) The results indicated that the areas of wetlands reduced 12270 hm during the period of 1988 to 2004. The proportion of wetland accounting for the research area descended from 43.4 percent in 1988 to 40 percent in 2004. The land use conversion matrix analysis indicated that 91.92 percent tidal flat, 80. 43 percent dike-pond, 62.21 percent mangrove forest, 54.63 percent reservoir, and 13.06 percent river transferred into other land utilization from 1988 to 2004.