| karst areas have a most typical frail ecological environment and complex human-land system. Its frailty is displayed in such distinct features as the strong sense of environmental mutation, low environmental capacity, limited ability of standing disasters, poor stability, sharp ecological competition and small quantity of living things. In the karst areas which cover 12% of the land, serious rock desertification is the major form of land desertification. Generally, karst rock desertification refers to the evolving process that leads to intense human-land conflict, destruction of vegetation, soil erosion, bare rock, failing productive forces of the land and the land surface appearing as desert from visual sense, because of the frail ecological environment formed by karst, and of the irrational social and economic activities of human beings. Karst is the most basic condition of Guizhou province. Now the special human-land system of karst has made the problem of rock desertification quite notable and typical in the karst areas of China and even the world. Thus, the research, from the global, on the spatial patterns, growth, evolution and driving factors of Guizhou's rock desertification, has great significance to preventing the rock desertification of the world karst areas.On the basis of the interrelated theories about the science of earth information, karst environment, as well as social and economic statistics, and with the support of the technology of remote sensing and geographical information system, the paper takes Guizhou area as the example to make a analysis on the spatial patterns, the process and the evolution mechanism, and the driving factors of the rock desertification. Meanwhile, to study of karst rock desertification, this paper makes a contrastive analysis of such special subjects as the ways of drawing information of rock desertification in the typical areas with plateau-gorge structure, the patterns and changes on the landscape ecology of rock desertification and the remote sensing monitoring on the ecological returns of controlling project. Altogether the paper is divided into two parts including nine chapters. The first part is concerned with the spatial patterns and evolution mechanism of Guizhou rock desertification; the second part is about the contrastive analysis of the typical sample areas with rock desertification controlling. The main contents and conclusions include:(1) To analyze the macro spatial patterns of Guizhou karst rock desertification. Based on the rank system of rock desertification and the remote sensing and geographical system, the author uses the visual interpreting ways of interchangeable human-machine to establish a 1: 100000 data base of rock desertification space. The data indicates that the rock desertification areas above the medium degree in Guizhou Province are 13187km2, covering 7.49% of the province; whereas those above the minor degree are 35920km , covering 20.39% of the province. Thus it can be seen that among the southwest provinces Guizhou stands in the firsts place in both the growth intensity and the proportion of rock desertification. Such a condition is very stern. And if it is seen from the different spatial patterns, the rock desertification of Guizhou province is intense in the south and west but weak in the north and east. According to the serious conditions of rock desertification and the conditions affecting the distributing patterns of rock desertification in rock properties and terrain features, the author divides Guizhou province into eleven intensity regions of rock desertification. Each of them has its obvious consistence in its own region but difference between regions. Moreover , three 3- dimension composing models of karst desertification are concluded based their different landforms in small scale, as a importantreference for implementing reconstructing project in deferent terrains.(2) To probe into the process and evolution mechanism of rock desertification. The regional nature factors and the irrational human activ...
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