舟山岩相潮间带动物群落结构的研究

Studies on the benthic fauna community structure of the intertidal zone of rocky shore in Zhoushan waters

本文应用数理统计方法研究了舟山海区岩岸潮间带中26个测站的春季动物群落结构。根据26个站的位置分为近岸区、近外海区和外海区3个区域。各站均以软体动物和甲壳动物为群落主要组成成分,群落种类组成数从近岸到外海呈增长趋势,且优势种亦从低盐种类向高盐种类演替。近岸区群落主要优势种为短滨螺Littorina brevicula、粗糙滨螺L.scabra、僧帽牡蛎Ostrea cucullata、白脊藤壶Balanus albicostatus等;近外海区为短滨螺、粒结节滨螺Nodilittorinaexigua、僧帽牡蛎、鳞笠藤壶Tetraclita squamosa squamosa、白脊藤壶等;外海区为粒结节滨螺,疣荔枝螺Purpura clavigera、条纹隔贻贝Septifer virgatus、日本笠藤壶T.japonica及藻类等。但群落个体密度和生物量从近岸到外海呈减少趋势。从近岸到外海,群落的Shannon-Wiener多样性指数H和Pielou均匀度J均增加,而McNaughton优势度D减少。群落结构从近岸到外海渐趋复杂。但整体上,舟山海区岩岸春季动物群落结构是比较简单的(绝大多数断面H值小于2.50,J值小于0.5。而D值大于0.6)。近外海区的群落结构比较相似于外海区的群落。根据平均聚类分析,这26个群落可以分为三个生态类型,即隐蔽性岩岸群落,半隐蔽性岩岸群落及开敞性岩岸群落。

The benthic fauna community structures in spring of the intertidal zone of rocky shore of 26 sampling sections in Zhoushan waters have been studied with statistical methods. These 26 stations lie in three ecotopes: neritic zone (8 stations), near off coast zone (8 stations) and off coast zone (10 stationns) . Mollusca and Crustacea predominate absolutely in all these fauna communities. The number of species in communities increases gradually from neritic zone to off coast zone, and at the same time the dominant species in communities evolve from low-salinity species to high-salinity species. The dominant species of communities in neritic zone are Littorina brevicula, L. scabra, Ostrea cucullata and Balanus albicostatus; in near off coast zone are L, brevicula, Nodilittorina exigua, O. cuculata, Tetraclita squamosa squamosa; and in off coast zone are N. exigua, Purpura clavigera, Septifer virgatus and T. japonica. But the individual densities and biomass of communities decrease from neritic zone to off coast zone. From neritic zone to off coast zone, the values of diversity index (Shannon-Wiener, 1949) and evenness index (Pielou, 1966) increase and the values of dominant indax (McNaughton) decrease and the benthic fauna community structures become more complicate. In general, the benthic fauna community of the intertidal zone of rocky shore in Zhoushan waters is very simple (in most stations, H'<2.50, J<0.5, and D> 0.6) . The community structure near off coast zone is similar to those off coast zone. According to the results of average cluster analysis, these 26 rocky communities can be divided into three types: sheltered rocky shores, half- sheltered rocky shores and exposed rocky shores.