| Wetlands, as a unique ecological system with highest productive forces on earth, are one of the most important environmental resources, which are named "kidney of the earth" and "super market of the living things". At present, conservation and wise use of wetlands has become an international trend. The key of wetland research is to obtain and analyze quantitatively wetland information. RS and GIS technology provide a new method for wetland research. Wetland identification and dynamic monitoring is an important application for remote sensing technology due to the increasing relevance of environmental considerations.The Poyang Lake, as one of the seven international importance wetlands in China, is the largest freshwater lake with an area of about 3000km . The Poyang Lake district is one of the five major plains in the middle and lower reaches of the Yangtze River. The exploitation and conservation of the Poyang Lake international importance wetland are of importance for the ecologic environment in Jiangxi province as well as in the whole country. This study used multi-source remotely sensed data (Radarsat SAR, Landsat TM/ETM and Terra Modis data etc.), related documents and geographical data, statistical data of water level and area through many years, combined with field investigation, to identify and monitor the Poyang Lake International Importance wetland. The involved researches include as follows:Firstly, the application of RS and GIS technology on wetland research is reviewed.The frequently used monitoring technologies of wetland dynamic change are also presented. It is pointed out that quantifying landscape pattern change of wetland and environment is the development trend of remote sensing dynamic change monitoring. In the meanwhile, we systematically analyze and evaluate the Contagion metric and Fractal Dimension metric for quantifying landscape ecological pattern change. The results show that the new metrics, Sqp and PPU are superior to Contation and Fractal Dimension metric respectively.As an up-to-date dynamic change measurement technology for terrain deformation, the mechanism and operational procedure of SAR differential interferometry are also analyzed. The emphasis is paid to the errors analysis and evaluation. An application example concerning Mani earthquake in Tibet is presented based on ERS-1/2 data.For the complexity of wetland edge extraction, a novel edge detection algorithm for remote sensing images, which combines the image gray level gradient and the fractal self-similarity character of image edges based on fractal theory, is developed in this study. The results of experiment are presented which show the effectiveness and the noise resistance of the proposed new algorithm for remote sensing image edge detection.To smooth coherent speckle noise and preserve edge information in SLC SAR images as precise as possible, a new algorithm called all direction auto-adaptive dynamic window filtering method based on coherent speckle statistic characteristic and analysis of spatial filtering algorithms for SAR image, is also developed in this paper. The proposed method can auto-adaptively modulate its filtering window size and selection of filtering pixels. Experimental result shows that the performance of the method is satisfactory in both speckle suppression and preservation of image details.Using Landsat TM data, we analyze the image brightness curves of typical objects in the Poyang International Importance Wetland. The optimal combination bands for TM image interpretation are TM4, TM3, and TM2 assigned with R, G and B primitive color respectively. Based on image interpretation results, we establish the wetland classification system for Poyang International Importance Wetland and classify the TM images of 1994 and ETM images of 2000. Using remote sensing post-classification dynamic change monitoring method, the wetland changes of Poyang Lake conservation area before and after 1998 Great Flood are analyzed and compared.We conducted a digital and rapid estimation of wetla...
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