海岛城市生态安全格局构建与优化策略研究——以舟山本岛为例

Construction and Optimization Strategy of Ecological Security Pattern in the Island City:A Case Study of Zhoushan Island

在当前全国开展国土空间规划时期,针对海岛城市的生态脆弱性和地理独特性,开展基于生态安全格局的精细化评估,对于规划编制具有重要的实践意义。以浙江省舟山市本岛为例,采用遥感生态指数(RSEI)评价整体生境质量;结合海岛地理特征和生态过程,运用最小积累阻力(MCR)模型,构建生态安全格局;基于要素叠置,研判空间冲突,提出国土空间的结构优化和分区管控策略。结果表明:(1)舟山本岛生态环境质量总体较好,但空间差异显著。RSEI高值比例达60.94%,由海岸向内陆呈三圈层递增趋势。(2)由“源地-廊道-缓冲区”构成的生态网络体系是全岛生态安全格局的关键。生态源地占比达43.32%,占据核心腹地;生态廊道67条,总长276.5 km,多位于南部源地斑块破碎区。(3)空间冲突集中于本岛中南部,主要与新城扩张和产业发展相关。在此基础上,研究提炼海岛城市“内源外廊周缓、集聚间有离析”的空间结构概念模型,并针对舟山本岛提出了“一轴四廊、五片九岬”的结构优化和“核心保育、缓冲修复、优化协调”的分区管控策略,旨在为海岛城市生态安全与科学编制国土空间规划提供借鉴。

In the current period of territorial spatial planning,island cities,as relatively independent natural geographical units,have fragile and unique ecosystems.Therefore,it is necessary to formulate spatial planning based on the refined assessment of ecological security pattern.In this paper,Zhoushan Island is taken as the study area,and the remote sensing ecological index(RSEI)is adopted to evaluate the ecological environment quality.Island geographical characteristics and ecological processes are considered for construction of ecological security pattern.Based on the analysis of factors overlapping and spatial conflict,the spatial optimization scheme and partition control strategy of territorial spatial structure are proposed.The research results show that:(1)The ecological environment quality of Zhoushan island is generally good,but the spatial difference is significant.The high-value coverage ratio of RSEI is 60.94%,showing a three-circle increasing structure from shore to land.(2)The core ecological elements of"source-corridor-buffer zone"stabilize the ecological security of the whole island.Ecological sources accounted for 43.32%,occupying the core hinterland;There are 67 ecological corridors with a total length of 276.5 km,which are concentrated in the patch fragmentation area of the southern ecological source area.(3)Spatial conflicts are concentrated in the central and southern parts of the island,mainly caused by the expansion of new towns and industrial development,the spatial optimization scheme of"one axis-four corridors-five areas-nine capes"and the strategy of ecological restoration zoning of"core conservation area,buffer restoration area and optimization coordination area"are constructed.By contrast between land and sea,this study forms two optimal patterns of island cities,namely"internal source-external corridor-peripheral buffer"and"aggregate with outlines",aiming at provide reference for the ecological security pattern and territorial spatial planning of island cities.