基于GIS的滇池流域景观格局优化

景观格局优化是景观生态学中的难点和热点问题。选择滇池流域为研究区域,在RS和GIS的支持下对2008年Landsat TM影像进行解译判读,获得景观类型图,运用最小耗费距离模型对区域景观格局进行优化。结合景观各组分生态系统服务功能价值和空间作用,构建了生态源地、生态廊道和生态节点等景观组分,以加强生态网络的空间连通性,提高景观格局稳定性,完善生态功能。源地具有较高的生态系统服务功能,需要维持和增大源斑块面积。所构建城市区域廊道、森林生态廊道、农业生产廊道应采取保持廊道规模,建立缓冲区,加强植被绿化,减少污染物的排放等措施以提高整个廊道的连通性。节点位于景观生态流和连通的重要位置上,需要加强控制。该研究对流域生态规划和土地利用优化布局有一定的参考价值。

A GIS-Based Landscape Pattern Optimization Approach for Lake Dianchi Watershed

Relationship between landscape pattern and ecological processes is a key issue of landscape ecology.By adjusting the components of landscape pattern,landscape pattern optimization aims to maximize the landscape eco-efficiency and enhance the ecosystem stability.The existing researches can not establish quantitative relationships between landscape pattern,functions and processes.The least-cost distance model describes the work or cost for the transformation from one landscape pattern to another with different resistance,and can interpret the relationships between landscape pattern and processes.In this study,the Lake Dianchi Watershed was chosen as a study area for landscape pattern optimization.With the supports of remote sensing(RS) and geographical information system(GIS),the landscape pattern was obtained through visual interpretation to the Landsat TM image of year 2008.The resistance was determined according to the valuation per unit area of ecosystem services.Taking the large water body as sources,the minimum cumulative resistance through the cost-distance model in ArcGIS was calculated.Combined with ecosystem services and spatial interactions of landscape types,a landscape functional network with sources,corridors and ecological function nodes was constructed.The optimization of landscape pattern strengthened the spatial connection of ecological network,maintained landscape stability,and improved the ecosystem services.The optimization measures and countermeasures for Lake Dianchi Watershed were proposed.For the high ecosystem services,important material support for regional economic and social development,and heavily vulnerability to human disturbance,it’s very important to maintain and increase the area of natural water body.In order to maintain high landscape connectivity,the urban area corridor,forest ecological corridor and agricultural production corridor should be built in Lake Dianchi Watershed.Intervention strategies,such as maintenance of the corridor scale,establishment of buffer zones,strengthening the green vegetation,reduce the emission of pollutants,and so on,can increase the connectivity of the entire corridor.The nodes,which are critical to the ecological flow and connectivity of landscape,should be controlled strictly.This study,which optimized the landscape pattern for the Lake Dianchi Watershed through the least-cost model with combination of ecosystem services and spatial interactions of landscape types would provide scientific basis and reference to ecological planning and optimal layout of land use in basin scale.