| With society, economic development and environment change, the public's ecological consciousness is being strengthened constantly. Ecological security and idea of the environmental health are rooted in the hearts of the people. River, as the birthplace of the civilization of human society, is closely related with watershed. Nowadays, people in a watershed pay more and more attention on their ecological environment. Carrying on research and protecting the environment based on watershed unit has become the trend of the modern environmental management.As a result of environment pollution and unreasonable development, the Aojiang River Watershed encounters a series of ecological environment problems in recent years, such as the eutrophication of the Shanzai Reservoir. With the digital elevation data and TM/ETM+ image, we integrated the RS, GIS, GPS technology into the research. Firstly, we applied hydrology basic principles to define the watershed drainage and sub-watershed of the Aojiang River Watershed. Secondly, we classified the land use of the sub-watershed that Shanzai Reservoir locates and monitored LUCC dynamically. Besides, the vegetation cover status and change around Shanzai Reservoir was described in detail. Finally, the landscape ecological principles were applied in Shanzai Reservoir landscape study in many aspects and two time scales. Integrating the study results, we not only can provide the decision basis for water quality protection of Shanzai Reservoir, but also can optimize the land use module and the ecological environment construction in the watershed.The main content is as follows:⑴ With the hydrology model software WMS and the digital elevation data source, the watershed outline, watershed drainage, the sub-watershed outline and the topology relationship of watershed drainage was established. In addition, parameters as sub-watershed area, perimeter, slope and shape factor were computed.⑵ After analyzing advantages of TM/ETM+ data, Tasseled Cap transformation, Principal Component Analysis and Normalized Difference Vegetation Index were chosen to enhance the image of 1986 and 2000. And some typical sample pixels were chosen to do statistics and analysis. On this basis, we adopted the best bands to classify the image of two years and calculate the precision of classification through the error matrix. Finally, by the post-classification approach, the LUCC during 14 years was monitored and the land use transfer matrix was built which can exhibit how and how much every land use type change. The results indicated that the Shanzai Reservoir land use has changed much with the driving force of reservoir construction, economic forest development and community succession.⑶ After computing Normalized Difference Vegetation Index(NDVI)of the two years, the vegetation cover change around the Shanzai Reservoir has been estimated with dense vegetation model. Then, the map of vegetation cover spatial distribution was acquired by ArcView GIS software. From the results, we can see that reservoir construction is the key factor to arouse the vegetation cover reduction around the Shanzai Reservoir. Secondly, the disturbances of economy development, wild fires and community succession that caused the vegetation cover change.⑷ Based on landscape ecology principle, GIS technology and the software FRAGSTATS, the landscape indicators of the Shanzai Reservoir were computed. With the help of indicators, we analyzed the landscape pattern of the watershed, especially the spatial heterogeneity, so as to probe into the function and trends of the watershed landscape further. The study result indicated that the patch shape, landscape diversity and the fragmentation of every sub-watershed in the Shanzai Reservoir Watershed have changed in different extent. The main driving force is the community succession and artificial disturbance.
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