Estimation of long-term change in desertification of oases of around Taklimakan desert

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In order to examine to what extent the oases surrounding the Taklimakan Desert have been converted into a desert, study was made by comparing the satellite images in the early period of 1960 with those of the satellite in the same district in recent years. As a result, the following have been explained. In the district surrounding the Aksu oasis, the oasis in the edge of the Taklimakan Desert, farmers in the coastal district of China are forced to move to the region as a policy of the Chinese Government, staring from around 1950. The farmers are asked to be engaged in converting the desert into a large-scale cultivating land of cotton as economic products, making use of a voluminous amount of the water flowing from the Tienshan Mountains. The area of the land that was changed from a bare land into a cotton cultivating land for the period of 40 years ranging from 1960 to 2000 is 2160 square kilometers. As a result of such conversion, the area of the farming land was multiplied and conve … More rsion of the oases into a desert apparently followed a path of regression. However as a backlash of inadequate irrigation, the level of underground water was heightened. Thus salts are liable to cover a large number of farming lands, and the lands had to be deserted. This resulted in degradation of many of the lands. Also such a type of the land has become causes of generation of dust storms. Meanwhile in the southern edge of Taklimakan Desert, water resources from the Qunlun Mountains are not abundant enough to be utilized in comparison with those resources in the southern edge, and slight expansion of the farming land was noticed upstream in the oasis. However scanty water resources were consumed downstream, which has invited regression of farming land contrarily to the above because scarce water resources were consumed upstream. Fewer water resources are available in the south than in the northern edge, which prevents the level of underground water from being heightened. Thus it is contrarily explained that just a few amount of salts of farming land is in existence. As seen above, it can be pointed out as a problem of the whole of Xinjiang Uyghur that the social backgroud such as a water resource controlling policy of the autonomous government of the Xinjiang, Uyghur, as seen, for example, in inadequate water distribution to farmers expedites destruction of the land. In the northern edge of Taklimakan Desert, as a backlash of inadequate irrigation, the level of underground water was hightened. Thus salines are liable to cover a large number of farming lands, and the lands had to be land degradation. This resulted in degradation of many of the lands. In the southern edge, water resources from the Qunlun Mountains are not abundant enough to be utilized in comparison with those resources in the southern edge, and slight expansion of the farming land was noticed upstream in the oasis. However scanty water resources were consumed down stream, which has invited regression of farming land contrarily to the above because scarce water resources were consumed upstream. Fewer water resources are available in the south than in the northern edge, which prevents the level of underground water from being hightened. Thus it is contrarily explained that just a few amount of salines of farming land is in existence. Less