内蒙古十大孔兑区土地利用类型变化与生态环境效应

Changes in Land Use Type and Ecological Environment Effect at Ten Tributaries in Inner Mongolia

[目的]研究十大孔兑区土地利用变化与生态过程之间的关系,揭示人类活动和土地利用与生态环境效应,为研究区土地利用结构优化和区域生态环境保护提供依据。[方法]选取2000,2010,2020年landsat影像,采用监督分类的方法结合地统计模块来获取不同时期土地利用数据和转移矩阵,对土地利用动态度、土地利用程度综合指数进行分析,在此基础上,运用数理统计等方法,选取NDVI值、生态环境质量指数等指标,对十大孔兑区生态环境质量进行综合评价。[结果]①研究期内,林地和草地面积比例变化幅度最大,水域面积比例最小,各土地利用类型之间转换频繁,林地“涨势”和草地、未利用地“落势”,十分明显。②十大孔兑区2000,2010,2020年土地利用类型转化的生态环境质量指数分别为0.5261,0.5373,0.5433,整体呈现上涨趋势;在空间分布方面,生态环境质量东高西低、南高北低。③年平均降水量、年平均风速会对生态环境质量产生显著的正向影响,年平均气温会对生态环境质量产生显著的负向影响。[结论]2000—2020年,城镇化快速发展的同时,十大孔兑区生态环境质量也在向好发展,研究区范围内生态环境质量呈现整体改善,局部恶化的局面,建设用地、林地、草地、未利用地之间的转化是主要原因,退耕还林等环境保护政策使研究区环境质量不断上升。

[Objective]The relationship between land use change and ecological process in the ten tributaries area in Inner Mongolia was studied to reveal the relationship between human activities,land use,and ecological environment in order to provide a basis for the optimization of land use structure and regional ecological environment protection.[Methods]Landsat images from 2000 to 2020 were selected.Land use data and transfer matrices in different periods were obtained by using the method of supervised classification combined with a land statistical module.The dynamic change of land use and the comprehensive index of land use degree were analyzed.On this basis,the NDVI value,ecological environment quality index,and other indicators were selected by using mathematical statistics and other methods to comprehensively evaluate the ecological environment quality of the ten tributaries.[Results]①During the 20 years of the study period,the proportion of forest land and grassland area changed the most,and the proportion of water area was the smallest,with frequent transitions between land use types,An obvious“upward trend”for forest land and an obvious“downward trend”for grassland and unused land were observed;②The ecological environment quality indexes of the transformation of land use types in 2000,2010,and 2020 in the ten tributaries were 0.5261,0.5373 and 0.5433,showing an overall upward trend.In terms of spatial distribution,the ecological environment quality was high in the east and low in the west,and high in the south and low in the north;③The annual average precipitation and annual average wind speed had significant positive impacts on the ecological environment quality.The annual average temperature had a significant negative impact on the ecological environment quality.[Conclusion]With the rapid development of urbanization occurring from 2000 to 2020,the ecological environment quality of the ten tributaries has also developed in a good direction.The ecological environment quality in the study area has improved overall and deteriorated locally.The transformation between construction land,forest land,grassland,and unused land is the main reason for changes in ecological environment quality.Environmental protection policies such as returning farmland to forest have continuously improved the environmental quality of the study area.