基于3S的呼和浩特市土地利用变化及其生态效应

Land use change and its ecological effect in Huhhot City based on 3S technology

在3S技术及相关模型支持下,对呼和浩特市1987—2004年土地利用变化及其生态效应进行了研究。结果表明,草地和耕地是呼和浩特市的主要土地利用类型。研究期间耕地和建设用地面积有所增加,其他土地利用类型面积有不同程度的减少。耕地的拓展及植被的恢复是研究区土地利用方式改变的两大主要方向。1987—2004年,呼和浩特市生态环境综合指数由0.401增加到0.408,生态环境质量有所改善。造林种草是改善生态环境质量最主要的驱动因子,其贡献率为25.30%。拓展耕地是恶化生态环境最主要的驱动因子,其贡献率为20.50%。研究区生态环境质量变化的空间差异显著,清水河县生态环境改善速度最快,主要驱动因子为退耕还林还草,其贡献率达57.89%。武川县生态环境恶化速度最快,主要驱动因子为耕地拓展,其贡献率为62.15%。

The land use change and its ecological effect in Huhhot City from 1987 to 2004 were analyzed, based on 3S technology and relevant models. The results showed that grassland and cropland were the main land use types in Huhhot City. During the study period, cropland and construction land had an increased area, while other land use types were in adverse. Cropland expanding and vegetation restoration were the two major trends of land use pattern change. The eco-environmental quality index in 1987-2004 increased from 0. 401 to 0. 408, suggesting that the eco-environment quality was improved in a certain extent. Forestation and grassland-planting were the main driving factors of eco-environmental quality improvement, with the contribution ratio of 25.30% ; while cropland expanding was the main driving factor of eco-environmental quality exacerbating, with the contribution ratio of 20. 50%. The differences in eco-environment quality change were spatially remarkable. Qingshuihe County got the fastest improving speed of ecoenvironment quality, which was resulted from the transferring of cropland to woodland and grassland, with the contribution ratio of 57.89%. The eco-environment quality of Wuchuan County decreased most rapidly due to cropland expanding, with the contribution ratio of 62.15%.