基于MSPA的南京市绿色基础设施网络格局时空变化分析

Analysis of the temporal and spatial pattern of the green infrastructure network in Nanjing,based on MSPA

以南京市为研究区,通过对1988、2000、2013年的TM/ETM遥感影像数据进行监督分类,获取了研究区3个时期的土地利用类型图,并采用形态学空间格局分析(MSPA)方法,获取了研究区3个时期的绿色基础设施(GI)景观类型图,进而对其时空格局变化进行了定量分析;采用景观连通性指数和景观图谱理论,对研究区核心区的景观连通性格局变化进行了定量评价。结果表明:1988—2013年,研究区GI总面积以较慢的速度递增,表明南京市实施的一系列"绿色南京"战略性工程取得了一定的成效;1988—2013年,核心区、边缘面积有所增长,而桥接区、分支则持续减少,环岛区整体上有所减少,表明城市景观破碎化程度增加,景观连通性有所降低;基于景观连通性指数的GI网络分析结果表明,南京市GI网络整体连通性、可能连通性水平均先减后增,基于图谱理论的GI网络连接度水平先增后减,从总体上来看,研究区GI的连通性水平依然比较低;南京GI网络格局的案例分析结果表明,融合MSPA、景观连通性、图谱理论的GI格局变化研究为GI格局变化分析提供了新的框架。研究结果可为研究区GI网络的规划与优化提供参考,对其他地区GI网络的规划建设也具有一定的借鉴意义。

We analyzed the temporal and spatial patterns of the land use types in Nanjing using TM / ETM remote sensing image data from 1988,2000 and 2013. Then,using the morphological spatial pattern analysis（ MSPA） method,we obtained the landscape types of the green infrastructure（ GI） for each of the three periods,and quantitatively analyzed its spatial and temporal patterns of changes. Finally,changes in the landscape connectivity of the core area were quantitatively evaluated using landscape connectivity index and landscape graph theory. The results show that,from 1988 to 2013,the total area of GI in the study area had a slower rate of increase,showing that the implementation of a series of ＂green Nanjing＂strategic project had obtained certain achievements. From 1988 to 2013,core area and edge area increased,but the bridge zone,branch continued to decrease,loop zone overall decreased,indicating the increase in the degree of urban landscape fragmentation and the decrease of landscape connectivity. The analysis of GI network based on the landscape connectivity index showed that both of the integral index of connectivity and the probability of connectivity decreased at first and then increased; the level of GI network connectivity which was based on graph theory increased at first and then decreased. Generally speaking,the level of connectivity of GI in the study area was still relatively low. The caseanalysis of Nanjing GI network pattern results showed that the research which combined MSPA with landscape connectivity and graphic theory provided a new framework for the green infrastructure pattern change analysis. These results can serve as a reference for green infrastructure network planning and optimization in the study area,as well as important guidance for other regions.