Construction of an Ecological Security Pattern and the Evaluation of Corridor Priority Based on ESV and the “Importance–Connectivity” Index: A Case Study of Sichuan Province, China

Abstract

Constructing an ecological security pattern (ESP) is an important means to describe, manage, and control ecological security. However, there are few related studies on functional analyses and evaluations of landscape elements, and the distribution of identified elements cannot fully reflect reality. To accurately depict ecological security and strengthen the role of landscape planning for policy formulation, we used the spatial distribution patterns of ecosystem services to adjust the ecosystem service value to accurately identify the distribution of ecological sources. The gravity model and Centrality Mapper tool are used to build an “importance–connectivity” index that evaluates the importance of ecological corridors in linking the sources and the contribution to maintaining the overall connectivity of ecological networks. The results show that (1) spatial heterogeneity exists in seven kinds of ecosystem services in Sichuan Province, China, and the high-level areas are concentrated in the central region. Moreover, (2) a total of 179 ecological sources and 445 ecological corridors with woodland and grassland as the main land use types are identified, and (3) a total of 153, 49, 78, and 165 corridors are divided into high importance–high connectivity, low importance–high connectivity, high importance–low connectivity, and low importance–low connectivity ecological corridors, respectively. The study provides a new framework for the construction of an ESP and for the priority evaluation of ecological corridors. To achieve balance between economic development and environmental protection, priority should be given to the protection of high-priority corridors when maintaining ecological security.