Study On The Ecological Forest Sustainable Management In Shunchang County Based On Ecological Fragility

In this study, the ecological forest of Shunchang County,Fujian province was taken as research object, using the remote sensing image of research area,and combining with the field investigation data to extract the thematic informations of ecological forest. We calculated the amount of soil erosion in sublot by the modified equation of USLE, and the area potential ecological fragility in ecological forest to analyze the relationships between the potential ecological fragility, soil erosion and vegetation coverage. Based on the features of different ecological positions, we advanced the optimization adjustment technology of the forest stand who located on the general ecological forest. Based on the principles of landscape ecology, evaluating and analyzing the rationality of forest stand by optimization adjustment, in order to provide theory reference for sustainable management of ecological forest, promote scientific forest management and play the ecological,economic,social benefits of ecological forest.The main conclusions of this study were:(1)The study based on the thought of hierarchical classification, adopted the object-oriented classification method, and applied segmentation arithmetic of Full Lambda-Schedule, then combined many objects which formed by it, to achieve to extract optimal segmentation scale from image information, preferably solve the result of "Salt and pepper"when extracted thematic informations with conventional methods, and higher improve the speed and accuracy of extraction.The result of accuracy verification showed that chinest fir plantation was 90%,masson pine forest was 88%,mixed forest was 90%,bamboo forest was 94% and broadleaf forest was 90%,the global accuracy reacheed 94.50%.(2)Establishing inversion model of vegetation coverage by NDVI, the average of relative error was 0.1829, and global accuracy was 81.71%. Using related addition informations, this study achieved the inversion of soil erosion of Shunchang Country that based on modified equation of USLE. It indicated that the general soil erosion of Shunchang Country was fine.(3)Though selecting factors and adopting correlation analysis method to select data, we selected slope,soil erodibility and rainfall erosion as factors which could embody potential ecological fragility. The result indicated that the terrain had great influence on the study area of ecological forest,and the weight achieved 0.5 which adopted principal component analysis to determine the weight of each factors. Based on this, the comprehensive index was adoptted to determinate the potential ecological fragility of the study area of ecological forest. The result showed that the total potential ecological fragility of Shunchang Country was in middle frail level, but the potential ecological fragility of ecological forest was higher, the result reflected the importance of the ecological niche in regionalization of ecological forest.(4)Based on the relationships between vegetation coverage, soil erosion and potential ecological fragility of the area, the study found that the area soil erosion were not obvious where vegetation coverage and potential ecological fragility are higher; but if not, soil erosion was particularly serious.The total analysis showed that vegetation coverage had great importance effects to stabilize the ecological fragility of the area, especially the higher potential ecological fragility area must strengthen the vegetation coverage to promote the stability of area ecosystem.(5)Evaluating ecological sensitivity of Shunchang Country, and according to the result of evaluation and area conditions, it proposed the measures that maintained the sustainable management of ecological forest. Then using the analysis index of landscape ecology, comparative analyze optimizatial result which simulate by using remoting image and the status of ecological forest,2008.The result showed that Shannon's diversity index increase 0.07 by optimization and fragmentation index is down 0.19,only 0.08. It totally reflected that the area ecological forest stand became rationality by optimization.