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Land degradation is widespread concern in the current global ecological problems, which seriously affect the health of societies around the world, economic development. China is one of the countries affected by land degradation is more serious, with nearly one-third of the land across the country are suffering from the threat of land degradation. View of land degradation enormous harm to agricultural production, economic development, the paper relying on research projects of the China Land Surveying and Planning Institute, Shaanxi Province, Hengshan County territory of remote sensing data, topographic data, and other reference data based The extent of land degradation in the study area, the quantitative extraction and assessment, and land degradation data in 1990 and 2002, two years compared to reflect 12 years of land degradation in the development of the area, for local government The land degradation governance to provide reference. This paper, the use of remote sensing and geographic information systems technology and methods, establish a set of evaluation index system based on a combination of different remote sensing data processing and information extraction, and terrain data and remote sensing data integrated treatment, combined with multi-source information for monitoring and evaluation of land degradation. Experiment by the paper, the main conclusions are the following: 1. The 2002 ETM Data by Yokoyama Ray Longwan region, through the inversion albedo image, extract normalized one image of the vegetation index (NDVI) and humidity image land degradation index model (DDI), this model generated image of the study area, the extent of land degradation. And found that the index and type of land use, a higher correlation with the practicality and feasibility. Based literature analysis explores the application status of land degradation monitoring and evaluation indicators, found that the vegetation cover, slope, organic matter content, type of land use, the level of income, biodiversity, water content and other indicators with a higher frequency of application, including vegetation cover and slope indicators application rate is relatively high, reaching 68% and 20%. The statistical results of these indicators can provide a reference to build the index system. Select the vegetation cover, slope, organic matter content, land use type, soil moisture, Saudi SPC six indicators index system was established, five of the extent of land degradation data obtained through remote sensing, geographic information systems technology level coding, the establishment of a comprehensive evaluation model for the information of the extent of land degradation in the study area. 4.1990 and 2002 land degradation assessment results show that: the land degradation in the region has improved in the last 12 years, and the local climate, economic data, and more in Northern implement shelterbelts and national prevention policy is closely related to land degradation.
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