温岭海岛潮间带大型底栖生物的群落结构

Communitystructure of intertidal macrobenthos in islands of Wenling,Zhejiang,China

为了解浙江温岭海岛潮间带大型底栖生物在沿海经济快速发展背景下的群落结构变化,2011年10月和2012年4月对温岭8个海岛8条断面开展了春、秋季2个航次的调查。本次调查共鉴定出潮间带大型底栖生物96种,包括软体动物40种,藻类29种,甲壳动物15种,多毛类6种,棘皮动物6种;平均生物量为1 794.16±1 148.08g/m2,平均丰度为679±497ind/m2,生物量和丰度均为秋季高于春季。温岭潮间带大型底栖生物主要以藤壶-荔枝螺群落为主,主要优势种为日本笠藤壶Tetraclita japonica和疣荔枝螺Thais clavigera,其生物量和丰度占80%以上,优势度非常明显。运用ABC曲线、等级聚类和nMDS对大型底栖生物群落结构分析发现,群落结构已受到中度干扰,稳定性差;与周边的洞头列岛、南麂列岛和嵊泗列岛相比,物种数仅为其一半左右。这种分布情况与其所处的生境有关,同时也表明受到人类活动(如污染和采捕等)的影响,群落结构次生化。

8 sections in islands of Wenling were investigated in October 2011 and April 2012 to assess impacts of disturbance on intertidal macrohenthos community structure. 96 species are identified, including 40 species of molluscs, 29 of macroalgae, 15 of carapaces, 6 of polychaetes, and 6 of echinoderms. The average biomass and abundance of macrobenthos are 1 794.16＋_1 148.08 g · m 2and 679_＋497 ind · m-2, respectively. The biomass and abundance in autumn are higher than those in spring. There is one main community structures in islands of Wenling, Tetraclita japonica-Thais clavigera. For all of the sections, T. japonica and T. clavigera are the dominant species and occupy over 80% of the whole biomass and abundance. According to hierarchical clustering analysis, MDS diagrams and ABC curve, macrobenthic community structure has suffered moderate disturbance with the consequence of poor stability in islands of Wenling. Compared to some neighbor islands （e. g. Dongtou, Nanji and Shengsi） in Zhejiang Province, the numbers of species are significantly less in islands of Wenling. Such distributional pattern of the habituating species in islands of Wenling appears to be closely attributed to the surrounding environment as well as to the impacts from anthropogenic activities （e. g. pollution, capturing, etc. ）, leading to the community structure degradation.