| Restoration Ecology is ranked as one of three hotpots in biological realm as well as biological diversity and global climate change in recent years, which is one fresh branch of Modem Ecology. Its primary research includes: the cause of degradation in ecosystem, techniques and methods of degraded ecosystem restoration and reconstruction, process and mechanism of ecology, research objectives of which are the destroyed ecosystems under the stress of natural catastrophes and human activities. The combination of obtained research achievement and extension effect in the ecological construction of soil and water conservation, sufficient exertion of ecological restoration ability, vegetation rehabilitation and ecosystem improvement widely and rapidly are the most effective approach to resolve the great problems on the slow steps of the prevention and cure of soil and water loss in China radically, which conform to the times. The Wuxi and Bishan county in Chongqing city is chosen as two of experimental units for "soil and water conservation of ecological restoration experimental project" by Ministry of Water Resources of People's Republic of China and Soil and Water Conservation Bureau of Changjiang Water Resources Commission. Wuxi county is located in typically fragile ecological strip--Three Gorges Reservoir Area and belongs to national ecological environment construction key region. Based on soil and water conservation project in Wuxi county this article designs the landscape health assessment system and analyses health classes of degraded ecosystem by applying fuzzy AHP method, discloses degraded characteristics in aspect of land use patterns in Wuxi county contrasted with Bishan county, puts forward ecological restoration models combined with soil and water conservation harnessing, analyses and compares soil fertility quality in biological communities of different ecological restoration succession phases and restoration measures. The research results mainly show:(1) The ecological degradation characteristics of Wuxi county include: some soil is thin and barren and its water and fertility conservation abilities are poor, gradual degradation of soil results in decrease of vegetation diversity and the vegetation community structure gradually inclines tc simplicity from complexity. The types of soil and water loss in Wuxi county mainly involve surface erosion and gully erosion. According to investigation, surface erosion area occupies 80% or so orerosion area, in which the slope farmlands surface erosion area accounts for about 70% of farmland erosion area.(2)In aspects of land use landscape, Woodland has the maximum fragmentation value in Wuxi County. The fragmentation values of others except habitation, barren land, paddy field are all higher than 1.7, which means those landscape are disturbed fiercely by humans and are the primary parts of ecological degradation landscape. The woodland is the primary ecological degradation landscape and its area occupies 45.7% of the whole county area. The degraded ecosystems include: >25° dry land, mountain dry land, low density forest, grassland of low cover rate or moderate cover rate, all of which are the sources of soil and water loss. The low intensity of soil and water loss accounts for 55% of the project area, the moderate for 23%, and fierce for 12%. The complicated mountain topography and disturbed degradation ecosystem cause the landscape characteristics of high patch size coefficient of variance, anomalistic patch shape and high fragmentation degree. The moderate erosive intensity and area are both the greatest, which mostly distributed in the degraded landscape affected by human unreasonable activities.(3)The results of landscape health assessment indicate: vegetation bestow rate contributes to landscape health assessment most, while soil and water loss and restoration ability in the second place. The land use affected by degradation most is >25° dry land, while dry land and paddy fields of mountain area in the second place, which show that self-adjustm...
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