| Climate change and desertification has become one of the hot topics of the the natural sciences in the twenty-first century, and good environmental conditions for human development can provide a stable life-support system. Gurbantunggut desert located in the central basin of northern Xinjiang, which is a closed desert composed of temperate fixed/semi-fixed sand dunes. Global climate and its impact is weakened, and the local climate and its impacts is significantly strengthened. through research this type of desert can greatly broaden the crossfeed mechanism theory of the desert and the climate, laid the scientific theoretical foundation for the areas of environmental planning and policy-oriented.In this article, through China’s meteorological science data sharing service network, we select three groups of data include temperature, precipitation, and wind speed from qitai station, kelamayi station and fuyun station in xinjiang during1981-2010respectively, then input into Excel for statistics processing, and use the dunes mobile index model and S drought index model to calculate the exponent value, then enter to mathematical software-MATLAB for deriving the simulation function and statistical change line charts, finally, making use of SPSS software to do the correlation analysis, using of the power spectrum to analysis relevant cycle at the same time. On the other hand, this paper selects TM image of5,4,3band which appropriate coordinates range is intercepted as a target image boundary to do the Supervise-Classification from GLCF/landsat imagery data network using of ERDAS. And by calculating original grid data, we compared the variation of sand dunes acreage and sand dunes surface properties of three areas to inspect the credibility of the rule of sand dunes mobile index in1990and2006.The main research results and conclusions are as follows:(1) The temperature regional difference of the edge of the Gurbantunggut desert was shrinking, at the same time, the precipitation regional difference was increasing and the district sandstorm activity has begun to ease, the impact of surface evaporation to the region was insignificance, the regional of climate law may be more related to human factors. meanwhile, It is the bad climate for period around1984and the severe period for desertification around1997, special period of climate anomalie mainly happen to climate Transformation Period.(2) since1981, the region’s climate get dry and cool from damp and hot, the desertification of corresponding process has begun to reverse. In the west margin Desert,the correlation coefficient of climate and desertification reached0.812, corresponding to the southern was0.764, the north was0.658, which were all up to significant related standards.(3) the region’s climate change and the process of desertification appear Many fluctuations, desertification status related to range and direction of climate fluctuation.negative climate fluctuation, smaller positive climate fluctuation which impact on sand dunes migration are not obvious, and the desertification for larger positive climate fluctuation may be more sensitive.(4) the different positions of the climate and desertification fluctuating frequencies Widespread4years or allowed4year cycle that related to abnormal area of winter-snow-cover in Eurasian land.(5) the migration of the sand dunes in this desert performance for the variation of sand dunes area and the proportion of surface vegetation, research shows that:west margin of sand dunes area reduce significantly, along with the northern and southern of offerested areas increased, so the natural condition of this desert had improved.This paper is divided into five parts:The first part is introduction, mainly introducing research background of "climate change and mutual feedback mechanism of desertification", research progress, thinking and technical line of this paper.The second part is the theoretical basis, and describes the influence of various climate factor on climate and the sand dunes, in order to expound the desert climate system of mutual feedback mechanism theory;The third part is the model and application, which is mainly introducing the model and the method;The fourth part is empirical research, exploring the region climate and sand dunes change rule and discussing the relationship between their migration in Gurbantunggut edge desert;The fifth part is the conclusion, key refining the special law of Gurbantunggut desert "climate change and mutual feedback mechanism of desertification", so as to expanse achieve the mutual feedback theory. |
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