| The research took a desertification region of Naiman in Kerqin, Tongliao City, Inner Mongolia including Weiliansu, Daqintata, Bagabolihe, Zhanggutai, Baiyintala and Baxiantong, as study area. Based on the Hierarchical Theory, the patches were divided into four levels including huge patches (>10km2), large patches (1.0-10km2), middle patches (0.2km2-1.0km2) and small patches (<0.2km2). The dynamic process and landscape patterns of the mobile sand and the response to desertification process were analyzed. Finally, the driving forces of the mobile sand dynamic changes and the response of desertification were discussed in order to provide foundations to the design of local sustainable development and useful database for combating desertification.Methodology is used remote sensing images in 1975, 1985, 1995 and 2005 to analyze the mobile sand characteristics and landscape structure changing. Firstly, the preparative works were including geographic correction, setuping interpretive symbols, and interpretation of the remote sensing images. The geographic correction was calculated by Erdas8.6 software; based on field investigation, land use maps and topographic maps, the interpretive symbols were imported as an event theme; land use maps were extracted by interactive method between operators and GIS (geographic information system) software ArcView3.2. Secondly, landscape pattern index were calculated by putting grid data into software Fragstats3.3. Then, under the support of software ArcInfo9.0, the vector data was converted to grid data which was gotten from the interactive method under several processes, including topology, cutting, and projection conversion. Finally, the study analyzed the dynamic changes of landscape structure by using gravity center moving and conversion matrixes of landscape types, including 1975 to 1985, 1985 to 1995, and 1995 to 2005. Consequently, by adopting artificial and natural factors, this study analyzed driving forces of respond with the mobile sand and desertification process. The result indicated that the artificial factor is a principal driving force of the mobile sand changes and desertification process.Major conclusions of this thesis are listed as follows:1. The dynamic change of the mobile sand had three processes. From 1975 to 1985, the areas of mobile sand increased with large extent, the accumulative areas of the mobile land patches at different levels increased significantly expect large patches, the small patches and middle patches of the mobile sand transformed from huge patches of the mobile and fixed sand. The huge patch of the mobile was transformed from semi-fixed sand, and it transformed to semi-fixed sand and fixed sand. From 1985 to 1995, the mobile area decreased, among which, the accumulative areas of small patches and middle patches of the mobile sand increased and they were transformed from semi-fixed sand and fixed sand. The accumulative areas of large patches and huge patches of the mobile sand decreased and transformed to semi-fixed sand and fixed sand. From 1995 to 2005, the mobile sand areas decreased continuantly, the small patches of the mobile sand increased continuantly because of the fragmentation of the large patches and huge patches of the mobile and transforming of semi-fixed sand and fixed sand.2. The results of the spatial pattern changes of the mobile sand showed that: From 1975 to 1985, the patch fragmentation increased, patch shape tended to be more complicated, the distribution tended to be centralized and evenness with different type patches, the centroids shifted slightly. The quantitative fragmentions of the mobile land patches at different levels increased expect large patches. The patch shapes of the mobile land patches at different levels tended to be more complicated expect middle patches. The shape fragmention of the mobile land patches at different levels increased except middle patches. The distribution tended to be scatter and evenness and the connect degree increased at each patch level. From 1985 to 1995, the quantitative fragmentation increased, the patch shape tended to be simple, the distribution tended to be centralized and unevenness, the connect degree decreased. The centroids shift to west in large extent due to combating desertification in Jiaolai River and decreasing of the mobile sand. The small patches and middle patches had same change trend: the number fragmentation increased, the shape fragmentation decreased and the patch shape tended to be simple. The large patches and huge patches also had same change trend: the number fragmentation decreased, the shape fragmentation increased and the patch shape tended to be more complicated. From 1995 to 2005, the fragmentation of number and shape decreased, the patch shape tended to be simple, the distribution trended be scatter and unevenness. The centroids shifted to southwest of east bank of Laoha River in large extent due to decreasing of the mobile sand. When the area was more than 0.2km2, the number decreased, the patch shape tended to be simple, the distribution tended to be more evenness. The connect degree of large patches and huge patches increased and distributed concentratively in the riverbed of Laoha River.3. The mobile sand response to desertification was analyzed by the regression analysis and principal component analysis (PCA). The results showed that the total areas and mean area of patches increased, patch shape tended to be complicated and fragmentized, the distribution tended be centralized, which was propitious to desertification process. The response of huge patches to desertification process was significant. The number of huge patches increased, patch shape tended to be complicated, the distribution trended to be centralized and evenness, all of which could promote the development of desertification. However the small patches number increased, patch shape tended to be complicated, the distribution trended to be centralized, which lead to negative impact on desertification degree.4. The PCA (Principal Component Analysis) results showed that there were four primary impact factors affecting on response of the mobile sand and desertification, their cumulative proportion were 43.517%, 23.020%, 15.175%, and 5.752%. For the first impact factor, the component loadings of population density, Pastural pressure intensity, small livestock and total produce value of agriculture, and they changed from 0.848 to 0.971. For the second impact factor, the component loadings of relative precipitation, evaporation and try index, and they changed from 0.772 to 0.846. For the third impact factor, the component loadings of relative mean wind velocity and gale days, they changed from 0.772 to 0.775. For the fourthly impact factor, the component loadings of affecting factors were all smaller. So the main drive forces included human activity disturbance and climate changes. Furthermore, the study advanced sustainable countermeasures of combating for desertification based on process and drive forces of the mobile sand changes and desertification process.
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