| For a long time, the Human have never stop the step to transform the nature world, the surface land use/cover pattern had suffered the disturb at the same time. The disturb come from the human act not only on the nature environment but also on the society and economic development. The LUCC has been a part of the Global changed research. Complicated Geography conditions and The loss of water and soil was most serious in the Three gorge reservoir region. Meanwhile, at the background of economic development and quickly urbanization, with the Chongqing's direct ruled by the central authorities and the Three Gorge Project's executed, the human's activity has non-stop to impact the land use/cover pattern and local Eco-Environment level. LUCC research is the base of the local eco-environment change research. It can help us to find out the succession process of the environment and the nature society changed, improve the eco-environment and the sustainable use of the land resource. The Three Gorge reservoir region was distributed in Chongqing City and HuBei Province, mostl of them in Chongqing city, also, it had the fast LUCC with the quickly urbanization and industrialization. In order to facilitate the recipt of data collection, we choose the The Three Gorge reservoir region in Chongqing city as the whole study area. According to the Great nature geography and economic difference, we chose the Jiangjin District, Zhong District, Wuxi District and FengJie District as the typical region of the study areas. This paper included four parts (The land use/cover changed pattern, dynamic of the land use and land cover change, the drive force of the LUCC, Simulated the trend of the LUCC in the future and the Eco-Environment effect of the LUCC).The result showed:1. Cultivated area and wood land has always been the main types of the study areas, the dry land is the most cultivated types. Because of the difference in the region of space, the situation was differed in the 4 typical districts. The WuXi and FengJie had a maximum area of woodland, there were the more cultivated areas in Zhong district and more cultivated areas and wood land in JiangJin district. Diversification of the land use types of view, the Diversity of the land use types in the lower reaches area were higher than the other areas, it has the stronger land use landscape stability in theoretically. It had the more land use degree In the upper reaches and the place near the Yangzhi River. In the middle reaches, the high elevation areas in the lower reaches had the lowest land use degree.2. Since 1986, the cultivated land areas increased in the first phase and reduced in the second phase, it revered on the wood land. The grass land and the un-use land reduced, water body and the built-up area continued to increase in the land areas. Jiangjin district and the Three gorges reservoir area (Chongqing) had the same trend of the land use change, but it differed in Fengjie district and Wuxi district. From the land use and land cover changed in the types of view, the ralative variety ratio of the cultivated land, wood land and grass land were more than the others, it dispersed on the study areas, but the water body and built-up areas are more concentrated. We can find out the land use and land cover types change (forest landscape succession, the transform between the grass land and the cultivated land, the quickly expand of the old urban areas, the new town come into being) by the RS imagine. We use the model to predict the trend of the land use and land cover change in the future. The cultivated land and the grass land will be reduced, and the wood land, water body and built-up area will increased in the future. It distinguished in the 4 typical districts, Jiangjin district and zhong district had the same LUCC trend of land use and land cover changed with the Three Gorge reservoir region; but in the Fengjie district, the cultivated land, wood land and grass land keep lost, the water body, built-up area increased; in the Wuxi district, the cultivated land, wood land, water body and the built-up area continued to increase, the grass land reduced. By the cultivated index, we study on the cultivated land's area change, from 1986 to 1995, it had tiny transformation, from 1995 to 2007, it increased so fast, also it distinguished in the spatial area, the index in the chongqing main city zone upriver of the study area increased on the negative, but it rose on the downstream region of the study area. The trend of the cultivated area changed on the 4 typical district were same with the Three Gorge reservoir region, the variety extent of cultivated landm in Jiangjin district and Zhong district were more than it on the Fengjie district and Wuxi district. To the wood land, because of the high elevation, the positive change focus on the east, south and northwest of the study area, and the negative change distributed in somewhere of the study areas.3. The result of the drive force of the land use and land cover change of the study area show: The land use and land cover types distributed in different elevation and slop area, the cultivated land were distributed throughout the middle high and even place, it reversed in the wood land and the grass land, the water body and built-up areas distributed in the low and even place. From 1995, the cultivated area in the low and even place reduced in evidence, but it increased in steep slope areas; in high altitude areas, a plenty of wood land had been increased, the grass land reduced, the water body and the built-up area had increased, From a geomorphological point of view type, Cultivated area were more in the low mountains, hills, and karst plains, wood land were distributed in the low mountain district with the largest areas, grassland in the knap and low mountains in the distribution of apparent, the more concentrated the distribution of built-up area in the karst hills and plains. From the soil types, the area of Purple soil, Yellow soil, Paddy soil were lager than others. From 1986 to 1995, the land use/cover change in different soil and physiognomy types were not obvious. Since 1995, change had accelerated noticeably, in the hills and low mountains had the fastest land-use change. Purple soil and paddy soil area were the most widely distributed, it had a better eco-environ-ment, with heavier human disturbance and a strong land use changed. From cultivated land changes of typical districts in the Three Gorges reservoir area (Chongqing), we find out the Jiangjin district is located in the upper reaches of the reservoir area and it's fastest growing economy and the rapid growth pressure of Non-agricultural population were the main driving factors of the cultivated land changed; The main driving factors of the cultivated land changed were the scientific and technological advancement factors and the impact of population movements by theThree Gorges Reservoir migrants; The first driving force of cultivated land changed in Wuxi district were the total population, and followed by the man-made policy factors (eg, agriculture, industrial structure adjustment); Zhong district is located in middle reaches of the reservoir area, which suffered the most strong impact of human policy factors.4. Here is one of the regions in China with high biodiversity, where the land use and land cover change impact the biodiversity obviously.â‘ Before the 1980's, widespread destruction of forest vegetation makes it a decrease in biodiversity, from the 1990's, although the forest area had been restored, but here's biological diversity there was no obvious increased.â‘¡Grassland area was reduced, the quality of the grass was decreased, the diversity reduced.â‘¢The bio-diversity had suffered the disturb come from the human activity of the engineering project, migration and the urban expand, and so on.â‘£The Three Gorges Project reservoir formed some water-fluctuation-zone, it would impact the the algae, vascular plants in the water-fluctuation-zone, on the other hand, on the other side; it could provides a variety of living environment for aquatic organisms. Land-use types affect the level of soil erosion, in the Three Gorges reservoir area (Chongqing), the highest soil erosion was on the cultivated land, and wood land was on the lowest soil erosion. In different regions, in the reservoir area downstream (Wuxi district and Fengjie district) soil erosion on cultivated land was strongest, followed by grassland and woodland; in upstream (Jiangjin District), the the higest soil erosion was on the grass land; The middle region (Zhongxian) had a higher soil erosion in the wood land.According to the fragmentation of land-use type situation, we had classified the 22 districts of the Three Gorges reservoir area (Chongqing), They belong to the eastern, central and western regions, Soil erosion decreased from east to west, They correspond to the fragmentation zone of agricultural-grassland, woodland area and the construction-water. Strong soil erosion (erosion intensity, very intensity of erosion and severe erosion) will increase the extent of land-use fragmentation, But the land-use landscape fragmentation increased the rate of soil erosion with the level was on the opposite side.5. From the landscape ecology, The Three Gorges reservoir area (Chongqing) Landscape heterogeneity was increased, the landscape was more stable, and it resisting ten days bounded disturbances capacity greatly increased, and it can resistant to the disturb of the outside more. From 1986 to 1995, the 'EVI'changed was every slow, but from 1995 to 2007, it increased so fast. by the model, we can find that the value of "EVI" index would increased in varying degrees, after 2007. The regional land use had a obvious sustainability. From the ecological risk, The upper and middle reaches of the reservoir area of ecological risk were more higher than the reservoir downstream. From 1986 to 2007, The Three Gorges reservoir area (Chongqing) had been to increased the overall ecological risk, but the high ecological risk areas will be more dispersed, and Reservoir downstream areas of ecological risk hasd increased.
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