| Research into terrestrial surface evolution(TSE) in the opencast mining field is fundamental not only to the proper exploration of mineral resources, the optimization of human habitat environment, but also to the alleviation of conflict between man and land resources as well as sustainable development of the mining field. This thesis targets the Pingshuo Opencast Mine Area(POMA) in the eco-fragile region of the Loess Plateau. Based on the spatial data acquired from RS and GPS and supported by GIS, the thesis makes a contrastive analysis of TSE in POMA from 1986 to 2005 qualitatively and quantitatively, and further advocates measures for the regulation of TSE and optimization control in the process of ecological rehabilitation. This paper mainly illustrates the following points:1.Based on a systematic conclusion on the research into the division and achievements of land use/cover, considering the fact of old landform use in POMA, the great destruction, wide variety and different utilization of land in the opencast exploration project, the drastic change of the vegetation structure, various allocation modes of vegetation and the complex transfers of land use, this thesis makes a practical division in the system of land use in POMA. The first category includes undisturbed land resources, disturbed land resources and reclaimed land resources. Based on this we have sub categories according to the internal features of land use. Compared with previous relevant research, the type of reclaimed land resources is added.2.According to the mode of stripping-dumping-building land-reclamation, the changes of land use from 1986-2005 in ATB, AJL and Dong are provided as follows: (1) The structure of land use has changed into a combination of undisturbed and disturbed land resources, and the structure emerged as a composition of undisturbed land resources, disturbed land resources and reclaimed land resources (2)The number of different types of land use is changing drastically. The area of undisturbed land resources has decreased from 36601.0 hm~2 in 1986 to 33379.51 hm~2 in 2005, with 161.07 hm~2 per year. In addition, the area of disturbed land has increased from 911.25 hm~2 in 1986 to 3206.36 hm~2 in 2005, and the area of reclaimed land resources has increased from 0 hm~2 to 926.46 hm~2.(3) The spatial evolution is in the form of grads due to the order and techniques of exploration obviously. The range of reclaimed land is gradually expanding, and the range of undisturbed land is gradually decreasing.3.According to digital terrain analysis based on DEM, a contrastive analysis is made between old landform and man-made landform, and results are as follows: (1) the elevation has increased about 30～100 m after the formation of man-made landform (2) the man-made landform has developed into a new form, the area below 6°has grown 326.59 hm~2 and the area above 15°has grown 502.15 hm~2 (3)the change of the old landform is not evident, and for the artificial landform, changes in the sunny, semi-sunny, shade, semi-shade and hilltop are obvious. The area of the shade and semi-shade has increased 188.13 hm~2, while the area of the sunny has decreased 152.88 hm~2.4.Based on the land use/cover changes and the features of landform, by means of a qualitative and quantitative study, this paper introduces several measures for the regulation of TSE and optimization control in the process of ecological rehabilitation, which include a redesign of the landform in order to prevent soil erosion and to keep stabilization, land suitability evaluation, the utilization of land on the base of suitable evolution, the optimization of the reclaimed land in terms of the structure, land use space structure and land property right. Further, a framework of a systematic construction of regulation of TSE and optimization control in the process of ecological rehabilitation is provided.
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