A Study On The Wetland Landscape Pattern Of Dongting Lake Useing RS And GIS Technique

Wetlands Science come of lakes and marshes school, It can be traced back to the earliest 17th century. After nearly 100 years of development, the scientific framework of wetland science has been built into the embryonic stage and been seen as the current international scientific, popular research areas of common concern. Dongting Lake wetland is China's largest freshwater wetlands, is the world's leading important wetlands. Human activities and river water and sediment take control of the situation in the evolution of lakes, Lake reclamation and sedimentation into the lake has accelerated the decline in the Dongting Lake ,with case Dongting Lake Chang sharply reduce its size, bottomland increased gradually, the wetland landscape elements of the structure and function has undergone tremendous changes.Using RS and GIS for Dongting Lake wetland landscape pattern analysis in order to grasp of wetland resources and change status timely and accurate ;study the trends on the wetland ecosystem and its landscape changes ;assess the pressure with wetland resources facing of ;analyse wetlands state; reveals the evolution of wetlands in the Dongting Lake wetlands in environmental restoration, wetland resources, utilization and protection of ecology and the development is of great significance. The main research results and conclusions are as follows:(1)The use of TM4, 5,3-band combination of the classification of the Dongting Lake wetland monitoring can to a certain extent, improve the wetlands classification of remote sensing image classification accuracy.(2)To satellite remote sensing technology for wetland landscape changes on not only better reflect changes in its area of change, from the overall grasp of the changes in the region, but also directly show that its spatial distribution of dynamic change, reflecting the development of its space, With other monitoring methods unparalleled advantages.(3)Through the landscape changes in the Dongting Lake, found that 87 to 2004, the Great Lakes region surrounding the wetland continued to show the trend of reduced year by year, to reduce the degree of landscape fragmentation. Dongting Lake wetland and internal changes in the overall trend after a two stage, their boundaries Ling is 98 after the implementation of the policy"Return the Field in Lakeside Areas to Lake". 98 years ago-Lakes area of the trend of narrowing, and 98 recovered after the water area, Sedimentation slowing down, but the lake is still expanding in bottomland.