Method Improvements And Applications For Ecological Networks Based On Least Cost Paths Model

The construction of ecological networks between remained habitats can improve landscape connectivity and alleviate the problem effectively by providing linkages between isolated habitat patches.In the landscape ecology,the target species ecological network is often constructed by the least-cost path model(hereafter LCPM)to improve the landscape connectivity among the discrete habitats and mitigate the negative impact of habitat fragmentation.Nevertheless,this traditional ecological network method based on LCRM is generally considered to have insufficient understanding of landscape structure changes and ecological processes of research site.Therefore,we used the landscape pattern index and the connectivity probability index to quantitatively evaluate the landscape structure and connectivity characteristics of the research area before and after the construction of the ecological network.The ecological network of the habitat of Trachypithecus francoisi,located in Fusui country,Guangxi Province,was used as an example to describe the optimization and application process of this ecological network method in detail.The following is the detailed process.1)to recognizes the habitat patches of target species.2)to divides different land use types of study area.3)to identifies the stepping stones of target species.4)to evaluates the landscape metrics and connectivity level of current situation.5)the resistant value setting of different land use,and generates landscape resistant surface.6)to constructs the ecological networks between each habitat using LCPM.7)to evaluates the landscape metrics and connectivity level of planning situation.8)the correlation analytical method was used to probes the relationships between landscape structure and connectivity.9)to identifies the important stepping stone patches which is the key strategic point.The results of this case application showed in the case that ecological network of the habitat of Trachypithecus francoisi was generated,LCRM could effectively improve habitat integrity and continuity,reduce overall fragmentation level,improve habitat quality and based on the structural and functional connectivity evaluation by landscape pattern index and connectivity probability index.Correlation results indicated that,the relationship between landscape structure changes and functional connectivity caused by the network was not strong,and the relationship between these two types of indices was not as significant as the inherent relationship between their structure and function.The innovations of the study are following: 1)This study improves the traditional method for ecological networks that was based on LCPM,and then that comes up with a systematic frame.2)This study generates ecological networks for target species by way of identifying stepping stones priority in conventional method.3)Different approaches that the landscape metrics and the landscape connectivity were used to quantitative analysis the changes of structural pattern and functional connectivity,before and after construction of ecological networks.Hence the evaluation of ecological networks was achieved.4)The correlation analytical method was used in this study,by analyzing the relationships between landscape structure changes and functional connectivity caused by ecological networks.5)The important stepping stones was identified by using patch importance index.