关键词: 沙漠化过程, 人类作用, 驱动因素, 科尔沁地区

Abstract: Based on the changes of temporal-spatial distribution of sandy desertified lands for the last 50 years, which had been in a process of expanded and reversed in the Horqin Region of China, the climatic variation and human activity have been taken as the major driving factors to discussed their impact on the process of sandy desertification. The climatic variations for last 40 years have affected directly the process of sandy desertification by different compounding model of temperature and precipitation in different decades, and affected indirectly the process by the human economic activities responded its variations. The climatic driving factor has presented the trend in favor of the desertification development in the region, but for last 10 years such function had been counteracted by the other function that was propitious to desertification reversion.The human activity is the much more active factor to the process of sandy desertification which mainly incarnates on the changes of the landuse fashion(from rangeland to farmland) and enhance of landuse intensity(over-cultivation, over-grazing and over-fuel collection). The fatal destruction to natural vegetation by human activities had accelerated the development of desertification. Take soil wind erosion as example, such human impact can increase wind erosion by 4 to 10 times contrasted with natural one. Along with the aggravation of desertification degree, the acceleration of degradation on soil nutrient, bio-diversity and bio-production can be 3 to 10 times or more contrasted with natural process. The human activities can reverse the sandy desertification depend on the reasonable landuse and adopting varied prevention and cure measure for combating desertification. From this point, one can say that the human driving factor play absolutely role on the process of desertification. So we would like to define the sandy desertification is that a land degradation characterized by wind erosion mainly resulted from the excessive human activities in arid, semiarid and part of sub-humid regions in North China.

Key words: process of sandy desertification, human impact, driving factor, Horqin Region, North China