Analysis of desertification process and driving force factors in grassland ecosystem of Xinjiang

The desertification area of Xinjiang Uigur Autonomous Region is the largest in China. The grassland ecosystem is the main ecosystem in Xinjiang. The occurrence and development of grassland desertification is related to ecological security and environmental quality of Xinjiang. The laws of distribution, characteristics and utilization in grassland ecosystem of Xinjiang were analyzed. The influence of natural factors and human factors on grassland desertification was discussed by analyzing the process of grassland desertification and the relationship of grassland ecosystem between other ecosystems. The result showed: (1) the type of desertification process was divided into 2 types. Ⅰ type was the process of desertification, salinization and degradation of desert grassland in the zone of plain and low hill, and Ⅱ type was the process of degradation in mountain grassland. (2) under the combined effect of human activities and the changes of hydrological environment on desertification, the grassland could transform into farmland, woodland, wetland, desert and community in the process of desertification. (3) the background of grassland desertification was the special topography, geomorphology, soil and climate. The natural factors provide the substance of desertification. The climate change was one of the main factors of desertification in the grassland of Southern Xinjiang and Eastern Xinjiang. (4) the unreasonable use of water resources was the main factor of desertification in the grassland of midstream and downstream. The reclamation and excavation grassland were the direct factors of desertification in the grassland around oasis. The longterm overgrazing and disorder grazing, low input of grassland management were the main factors of desertification in the pasture and mowing grassland. The driving force of grassland desertification has the characteristics of regionalism, multifactor and the desertification was the results of combined effect of natural factors and human activities.