A Study Of Landscape Change And Optimization In Shapotou National Nature Reserve Of Zhongwei, Ningxia

Shapotou Nature Reserve located in the arid area of Northwest is a typical desert ecological types of national nature reserve in north China. It plays an important role as ecological barrier to promote the benign development of regional ecological environment. Since its establishment, human production and ecological construction activities have an effect on the change of landscape pattern. And regional landscape pattern changing is influential in ecological environment and ecological processes. Landscape optimization study based on an accurate information of landscape pattern has an important theoretical and practical significance for regional ecological planning and construction.In order to achieve the reserve landscape information, the remote sensing images from1990to2011were interpreted using a method combining supervised classification and visual interpretation. Using the landscape dynamic model, transfer matrix and landscape index, the information of landscape pattern changes, its driving factors and landscape pattern problems were all analyzed. On the basis, the study try to simulate landscape ecological flow operation process to identify ecological appropriate area of regional dominant landscape, potential ecological corridors and ecological nodes, then build the landscape pattern optimization system. The main studies are as follows:(1) The landscape changes significantly from1990to2011. The area of farmland, timber forest, waters and construction land increased and that of grassland and desert decreased. Meanwhile the area of shelter forest and desert grassland show fluctuations. The major patterns of landscape change were the conversions of desert and grassland to farmland, timber forest and waters. And there is three reciprocal transformation among shelter forest, desert and desert grassland. The dynamic degree of landscape increasing year by year indicates that the intensity of human disturbance increased. There exist the phenomenon of dominant landscape transformation from the natural landscape to the operating landscape. Meanwhile, the dominant landscape pattern change have an impact on the overall landscape pattern change. The analysis of landscape index showed that landscape diversity index, the patch irregular degree and the patch dispersion increased from1990to2007. While, after2007, there is a transformation of regional dominant landscape from desert to timber tree. And landscape diversity index, the patch irregular degree and the patch dispersion decreased. The types of landscape with higher degree of landscape pattern change are cultivated field, water and desert, while the types with lower degree are desert grassland and shelter forest.(2) The scope of the dominant landscape development is designated into three zones according to ecological suitability degree, including development area, transition area and protected area. Business landscape were limited in development area. Small vegetation patches were introduced into build ecological nodes and ecological corridors in transition area. Original natural landscape were reserved in protected area. Meanwhile, the cultivated land and timber forest should be spatially continuous development. The shelter forest system should be built around the farmland and the forest. The buffer area should be built in the conflict zone with different landscape function.