Research On Cause Of Grassland Degradation And Environmental Management In Maqu County

Maqu County is the the main water conservation region in the Upper Yellow River and with great value of grassland ecosystem services. Livestock husbandry is also the main production and living patterns for local people. For recent years grassland was subject to serious degradation and desertification due to global climatic change and artificial factors, which not only obviously restricted the development of economy in Pastoral Areas and the improvement of local Tibetan people's living standard, but also directly threatened to the ecological safety of the region along Yellow River. So under the background of the Great Development of West Region, it's important for us to study on the interactive relationship between alpine grassland and narural & artificial factors for solving the issue of grassland degradation in Maqu County.By means of field survey, history datum analytic methods and quantitative study, on the base of natural, social, economic conditions of the source region, the author analyzed the status of grassland degradation and its harm to local ecoenvironment, society and economy systems, and studied the cause of grassland degradation and the leading factors by the methods of combining theory with practice, combination of qualitative and quantitative. According to the estimation of NPP, the quantity of overgrazing was defined. The effects of temperature and overloading on grassland desertification were simulated by Cobb-Dauglas function. And management countermeasures were proposed based on ecosystem service valuation of grassland in Maqu County, which should take for changing overgrazing, controling grassland desertification and improving people's living standard as center and establish supporting policies favorable to grassland resources sustainable utilization. Conclusions were as follows:Grassland degradation is quite serious in Maqu County. For recent 20 years, the area of grassland desertification along the Yellow River extended gradually. The average speed of desertification reached 23.27% during the 17 years from 1985 to 2003. The serious eco-environment problems of the region gravely restricted the development of local husbandry production and regional economy.The causes of grassland degradation in Maqu County are double effects of natural factors and artificial factors. The key natural factor that affected grassland desertification in Maqu County was temperature increasing, especially the accumulated temperature of≥0℃; and the key artificial factor was overgrazing. Actual carrying capacity of Maqu grassland has increasing persistently during the 50 years. The effect degree of temperature increasing and overgrazing on desertification was analezed using production function, the results were that the effect of the temperature increasing to grassland desertification accounted for 34.39% and overgrazing for 65.61%. Desertification phenomena appear on grassland when the accumulation effect of overgrazing reaches some degree. That accumulated number of overstocking increases newly ten thousand sheep units would cause the area of 3.14hm~2 for grassland desertification.The value of ecosystem services in Maqu County is so large as to 96.25×10~8 yuan/a now. Based on the calculation of ecosystem services, the standard of ecological compensation should be the valuation brought by the overload. The policy contents of ecological management should include: industrial development, ecological emigration and herdsmen settlement, grazing management, technology popularizing, the control of population growth and promoting social progress.