太子河流域景观格局时空演变及其对水源涵养的影响

Spatial-temporal evolution of landscape pattern in the Taizi River Basin and its impact on water conservation

基于InVEST模型,研究了太子河流域2000—2020年水源涵养时空分布特征,定量评估了研究期土地利用变化及景观格局演变,并采用皮尔逊相关分析法和地理加权回归模型研究了景观格局和水源涵养量之间的关系。结果表明:景观水平上,最大斑块指数、蔓延度指数和聚集度指数越高,则水源涵养量越高;类型水平上,耕地数量越多、斑块密度越大、景观分离度越大,林地优势度越高,建设用地景观越分裂、斑块数量越少、斑块密度越小,则水源涵养力越高;空间上,流域大部分区域景观蔓延度指数对水源涵养起正向作用,耕地斑块数量、斑块密度分别在流域中南部和西北部对水源涵养起正向作用,林地斑块面积比在全域对水源涵养起正向作用,建设用地斑块数量、斑块密度、斑块面积比对水源涵养均以负向作用为主。

Based on the InVEST model,the spatial-temporal distribution characteristics of water conservation in the Taizi River Basin from 2000 to 2020 were explored,and the land use change and landscape pattern evolution during the study period were quantitatively evaluated.Using Pearson correlation analysis and geographical weighted regression model,the relationship between landscape pattern and water conservation was analyzed.The results show that,at the landscape level,the amount of water conservation increases with the largest patch index,contagion index,and aggregation index;at the landscape type level,the capacity of water conservation gets higher when the cultivated land has larger area,higher patch density,and higher degree of landscape fragmentation,the forest land has higher dominance degree,and the construction land has smaller number and lower density of patches,with landscape being more fragmented.Spatially,the landscape contagion index plays a positive role in water conservation in most area of the basin,the number and density of patches in cultivated land have positive effect on water conservation in the southern central part and the northwestern part of the basin,respectively.The percentage of landscape of forest land has a positive effect on water conservation in the whole region,while the number and density of patches and percentage of landscape of construction land mainly play a negative role in water conservation.