Analysis Of Grassland Degradation And Influencing Factors Based On Remote Sensing

For the response to global climate change and utilization intensity of grassland effect, people aware of the necessity and importance about protecting the grassland, China since 1985 passed the law to protect and manage grassland, and due to the different regional execution status,social and natural conditions,natural conditions, livelihood, economic benefits and other factors cause grassland degradation, land reclamation, excessive grazing and so on.In recent years,large areas of grassland degenerated in northern China,it has become a major issue of environmentand resources.So it is urgent to find out the extent of grassland degradation,the present situation;reveal the problems and influencing factors of grassland degradation,and put forward feasible suggestions or countermeasures. In this paper, based on MODIS data using least squares method to analysis grassland degradation combined with high marks, images, elevation, land use data and social economic statistical data using spatial overlay and correlation analysis was used to analyze the influencing factors. The results are as follows:(1) In recent 15 years whole grassland has improved in Xilin River Basin, degradation is minor, mainly concentrated in Xilinhot City and surrounding urban area and southeastern baixinxile and bayanxile ranch near, degraded grassland accounted for only 4.14%, the moderate 1.52% degradation, light degradation 2.6%, serious degradation 0.02%.(2) To make difference-value analysis of grassland condition in 15 years, the results showed that the early stage of non degraded grassland was 91.90%, 84.03% in the middle, and 99.60%in the later stage. In the early stage, the grassland degradation was mainly mild, with some moderate degeneration and a small part of the severe degradation. In the medium term, the mild and severe degeneration of the upper stage decreased, and the moderate degraded grassland was increased. In the later stage, the phenomenon of grassland degradation showed a decreasing trend, and the slight degradation was significantly reduced, and the moderate degradation and severe degradation were also decreased.(3) according to the different periods of grassland degradation in the evolution, evolutionary type is divided into four categories, and the results showed that the invariant form accounted for 75.67%; return variant 15.87%, among them what deteriorating and improving type as the main, single variant 8.25%, mainly improving; layer variant form least, which percentage among them in proper order: improvement, deteriorated and become and improve the type and layer improve and deteriorating, layer becomes worsening; grassland conditions in the study area has been relatively stable.(4)In the aspects of influenceing factors of grassland degradation, Climatic factors which have significant effects on grassland degradation are mainly precipitation, and exist a month lag effect; the topographic factors are mainly the elevation; place of residence, mining, industrial activities and traffic have obvious influence on the grassland deterioration, while to close the living, mining, industry, road, affects of grassland degradation especially are very significant.Also the impact of policy and land use on the degradation of grassland can not be ignored. Grassland degradation is divided into the degradation of the quality of its own and the reduction of the number.