Analysis of spatial-temporal evolution and it's driving forces of construction land and cultivated landscape in Taihu Lake Basin

Based on the land-use satellite image datasets of 2000,2010,and 2015,the grid transformation,landscape gradient,logistic regression model,and CLUE-S model were integrated to analyze the spatial-temporal evolution and driving mechanisms of construction land and cultivated landscape in Taihu Lake Basin. The results showed that the areas of the construction land increased significantly,while the areas of cultivated land decreased in the basin from 2000 to 2015,respectively. The cities and areas along the Shanghai-Nanjing traffic line showed high construction landscape gradient,with construction land gradually expanding to the surrounding areas,especially in the peripheral areas of metropolis. Among them,in Suzhou,Wuxi,Changzhou,Shanghai,and Hangzhou,the areas of construction land and cultivated land changed more prominently. The maximum increase in construction land was 0.92 km~2 per unit area,and the proportion of construction land with high landscape gradient( 50 < DI ≤ 100) increased from 3. 02% to 31. 27%. The maximum diminution of the cultivated land was 0. 95 km~2. However,the landscape changes for the center of original metropolis and the western and southwestern hilly areas of the basin keep relatively small. Such changes for both landscape types were deeply influenced by the natural environment and socio-economic factors,and the latter were shown to be the dominant driving forces. According to the CLUE-S model simulation,there were significant differences in the spatial-temporal evolution of both landscapes withdifferent scenarios in 2030. The area of high construction landscape gradient in the natural developmental scenario would be the largest. Under the ecological protection scenario,the increase in construction land would slow down,but the cultivated land would still be reduced significantly,and most of it would be converted to ecological land. However,the area of high cultivated landscape gradient under the situation of cultivated land protection would be the largest. This study revealed spatial laws of conversion from cultivated land into construction land in Taihu Lake Basin. Thus,these results can provide bases for land management decision-making and urban planning and construction,and can also provide references to resolve the contradiction between economic development and land-use balance.