南京市景观格局演变与廊道网络构建研究

Study on the Changes of Landscape Pattern and Construction of Corridor Network of Nanjing City

以南京市1990、2000和2010年TM遥感影像为数据源,选取合适的景观格局指数,运用景观生态学原理和RS、GIS技术,揭示南京市20年的景观格局演变特征。通过生态源点信息提取、最小累计距离耗费模型,构建南京市廊道生态网络。结果表明:①1990—2010年,南京市景观格局变化显著,在斑块类型尺度水平上表现为农田面积大量减少、破碎程度增加,建设用地面积增加、趋向集聚化发展,林地面积增加、斑块形状复杂化,水体景观比例先减后增、形状趋于规则化。在景观尺度水平上表现为景观整体多样性、破碎程度增加,自然景观空间异质性增强,各景观类型斑块形状相似化发展;②在累计耗费距离大的源地间构建垫脚石,可以有效增强景观的连通性、优化生态网络结构、发挥其生态服务功能。

Based on the three TM images of 1990, 2000, 2010 and selected landscape pattern index, the changes of landscape pattern of Nanjing city in the past twenty years were studied by techniques of remote sensing （RS）, geographical information system （GIS） and landscape ecology theory. The ecological corridor network was built on basis of extracted ecological source regions and the least-cost distance model. The results showed that： The changes of landscape pattern of Nanjing city were notable. Class-level indexes indicated that the area of farmland landscape decreased and the degree of patch fragmentation aggravated. The area of construction land increased, and it tended to distribute intensively. The proportion of forest increased and the shape of patches was more complex. The proportion of water firstly decreased, then increased, and the shape of them became more regular. Landscape-level indexes indicated that biological diversity and the degree of fragmentation increased. Spatial heterogeneity of the whole landscape was enhanced and the shape of these four landscape patch types became similar; Stepping-stones which were used to enhance the connectivity and optimize the ecological network should be built, which can help improve the ecological services.