| Land use and land cover changes(LUCC) has been the focus and the frontier problem of global change research and it has been paid great attention by scientists all over the world. With the rapid development of our country economy and the increase of population, the pattern of land use and land cover has changed. The contradiction of the economical development and the ecological environment is more and more prominent. The study on the dynamic change of LUCC in typical areas is one of the important ways to understand global changes.In view of our country fast urbanization, on the basis of databases of land use in 1990, 2005 and 2007, temporal-spatial characteristics of urban land use change and land use types of Tai'an urban were analyzed systematically by use of the advanced 3S technique. The spatial character of landscape pattern for land use was studied based on method and theory of landscape ecology tendency of the land use change from 2005 to 2035 was predicted. Using PCA, recursive analysis and BP neural network method, an indexes system which showed the driving factors effect on land use change was designed according to factors analysis. Through above analysis, the land use impact in the eco-environment of the study area was integrative appraised by method of Analytic Hierarchy Process (AHP), ecological service value and GIS mapping. The main results and conclusions were as follows:1) Agriculture land is the main land use structure in Tai'an urban in 2005 and the ratios to total area were respectively: cropland 41.94%, orchard land 15.58%, forestland 20.21%, urban land 8.39%, residence area 7.38%, water area 3.68%, and unutilized land 2.82%.2) In the sight of the change range of land use from 1990 to 2005, the area of arable land, unutilized land and water area decreased, but the urban land, forestland and orchard land increased. In the change speed of land use, the decreasing speed were respectively arable land, water area and unutilized land from fastest to slowest, and the increasing speed were respectively urban land, orchard land and forestland from fastest to slowest. Among them, urban land changed fast and others were changed very slowly.3) There was an obvious differentiation of spatial distribution of relative change rate in Tai'an urban. Land use degree index which was smaller than 300 increased in study periods. The ratio of land use degree was bigger than zero. As a whole, the land use in Tai'an urban was in an expansion period, but there was also an obvious differentiation of spatial distribution of land use degree change. Land use degree of various villages and towns was in the expansion period, but that of individual villages and towns was in the adjustment period.4) In the sight of the conversion of land use, the significant changes took place in study period. The reduced area of arable land mostly converted to orchard land, forestland and urban land. The increase of urban land and residence area mostly came from arable land and orchard land and that of forestland mostly came from arable land and orchard land. Meanwhile the increase of orchard land mostly came from arable land and the decrease of unutilized land mostly converted to orchard land and forestland.5) Based on the methods of quantitative analysis and fractal theory, the urban landscape mosaic structure of the study area was studied and the results were given as follow. The patches shape of the landscape structure types tend to complexity and diversity. The degree of the landscape fragmentation and that of the interference of mankind on landscape increased. The area of the dominant landscape type and the degree of dominance were descent and the diversity index was ascent. The arable landscape which disappeared in large scale was affected greatly. The scale of orchard landscape increased and the effect of human intervention on its patches structure was not obvious. The forest landscape distributed in large area and the respond of the landscape pattern to human intervention was not sensitive. The effect of human activity on the water landscape was not obvious. The urban land was a landscape type whose change scale was the largest and change speed was the fastest and the structure of urban land was affected greatly by the urbanization.6)Using Markov model to calculate the probability matrix of land use and conversion, the change trend of land use was forecasted. In the following 30 years, the area of arable land will continue to decrease and that of water area will slightly reduce. Corresponding, the area of urban land, residence area, orchard land and forestland will all continue to increase. Using the Grey Model of GM(1,1) to predict the change trend of urban land, if current trends continue, the area of urban land in Tai'an urban will increase 17.03%,that is to say , it will increase 107.86 hectare per year on average. 7)The dynamic mechanics of driving force for the land use change in Tai'an urban was studied by the integration of qualitative analysis and quantitative calculation, principal component analysis, BP neural network and canonical correlation analysis. The results showed that the driving force of the land use change was population and economic development factor and the interaction of the factors on the land use change of Tai'an urban was different.8)Using the model of eco-region risk index, the relationship of land use structure and ecological risk was set up and the ecological risk index was calculated at different range of spatial and temporal scales. The ecological risk index of Tai'an urban increased slightly from 0.1409 in 1990 to 0.1414 in 2005. The distribution of ecological risk was different significantly. In 1990-2005, the regions whose ecological risk were high were respectively Daimiao agency, Caiyuan agency, Shengzhuang town, Qiujiadiaan town, Xujialou agency and Shanggao agency in Taishan District, Fan town, Jiaoyu town, Beijipo town, Manzhuang town, Shankou town and Tianping agency in Daiyue District. The ecological risk index was lower than that of others in the regions which were far from the urban, especially the northeast of Tai'an urban, because there was more forest land and less proportion of industrial and mining, residential land and traffic lands, so the environment effect was less. From the space distribution pattern, the value of ecological risk index distributed in a line way or spots along the urban and main lines of communication and the distribution area decreased gradually from inside to outside.9) The effects of land use changes to ecological service value in Tai'an urban was analyzed by the Costanza method from 1990 to 2005. The results indicated that the total ecological service value was descent,the differentiation of the spatial distribution was obvious,and the contribution of the towns was various. The total value of the ecology service lost 281,163,700 Yuan during 15 years and it lost 13.87 Yuan per hectare on average.
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