红树林林分空间结构健康指数的测度与应用

Health index of spatial structure of mangrove forest stand

为了进行红树林林分结构与功能健康的量化研究,应用混交度、大小比数、角尺度和竞争指数等空间结构指标,构建了红树林林分空间结构健康指数;同时运用该指数分析了湛江港特呈岛白骨壤林分空间结构健康状况。结果表明:全林地白骨壤空间结构健康指数为0.53,为亚健康等级;外带的白骨壤纯林空间结构健康指数为0.40,为亚健康等级,但接近不健康或濒临崩溃;中带的白骨壤和红海榄混交林空间结构健康指数为0.50,为亚健康等级,但接近中等健康水平;内带的白骨壤、红海榄和木榄混交林的空间结构健康指数为0.59,处于中等健康水平。因此,特呈岛全林地白骨壤空间结构健康状况较差,混交林空间结构健康比纯林好。

A healthy quantitative research on mangrove forest structure and function was conducted in this paper. The health index（ HI） of spatial structure of mangrove forest stand was constructed by using spatial structure indicators including mingling,neighborhood comparison,neighborhood pattern and competition index. The HI was used to analyze the health of spatial structure of Aricennia marina forest in Techeng Island. The results indicated that： the HI of A. marina full woodland was 0. 53,belonging to the sub-health grade; the HI of pure A. marina forest was 0. 40 in outside tidal zone,belonging to the sub-health grade,close to unhealthy or on the verge of collapse; the HI of A. marina and Rhizophora mixed forest was 0. 50 in middle tidal zone,belonging to the sub-health grade,close to medium health grade; the HI of A. marina,Rhizophora and Bruguiera gymnorrhiza mixed forest was 0. 59 in inside tidal zone,belonging to the medium health grade. Therefore,the health of spatial structure of A. marina in whole island was relatively poor. The health of spatial structure of mixed forest was better than that of pure forest.