夏季庙岛群岛大型底栖动物群落特征

Community characteristics of macrozoobenthos in the Miaodao Archipelago in summer

根据2022年8月大潮期间庙岛群岛岛屿的潮间带和潮下带大型底栖动物的调查结果,对其种类组成、数量分布、优势种、多样性以及群落结构特点进行了研究。结果表明:本次潮间带定量调查共鉴定大型底栖动物52种,其中甲壳动物最多(17种);定性调查共鉴定42种,软体动物最多(30种)。潮下带定量调查共鉴定大型底栖动物39种,低于潮间带定量调查,其中软体动物最多(26种)。潮间带大型底栖动物平均丰度为234个/m^(2),平均生物量为82.82 g/m^(2)。潮下带平均丰度为180.2个/m^(2),平均生物量为708.02 g/m^(2)。潮间带大型底栖动物多样性指数(H′)、丰富度指数(D)和均匀度指数(J′)平均值分别为1.187、1.723和0.540;潮下带H′、D和J′平均值均高于潮间带,分别为1.301、2.204和0.669。在本次潮间带定量调查中,大型底栖动物优势种为施氏玻璃钩虾(Hyale schmidti)、平背蜞(Gaetice depressus)、潮间海钩虾(Pontogeneia littorea)等。潮下带优势种与潮间带不同,为紫贻贝(Mytilus galloprovincialis)、东方缝栖蛤(Hiatella orientalis)、锈凹螺(Chlorostoma rustica)等。聚类分析和nMDS分析表明,在20%的相似性水平上,庙岛群岛潮间带和潮下带大型底栖动物分别可划分为4个和3个群落。与周边海域潮间带历史资料相比,调查区域的大型底栖动物在物种数量、平均丰度和平均生物量方面处于中等水平。

The macrozoobenthos present in the intertidal and subtidal zones of the islands of the Miaodao Archipelago were investigated in August 2022 to study the composition of species,quantitative distribution,dominant species,biodiversity,and community structure.A total of 52 macrozoobenthic species were identified during the quantitative intertidal survey,and crustaceans were the richest taxon(17 species).A total of 42 species were identified during the qualitative intertidal survey,and mollusks were the richest taxon(30 species).Overall,39 macrozoobenthos species were identified in the subtidal zone,which was less than the number of species identified in the intertidal zone,and mollusks were the richest taxon(26 species).The average abundance and biomass of macrozoobenthos in the intertidal zone were 234 ind./m^(2) and 82.82 g/m^(2),respectively,and those in the subtidal zone were 180.20 ind./m^(2) and 708.02 g/m^(2),respectively.The average values of the diversity index(H'),richness index(D),and evenness index(J')of the macrozoobenthos in the intertidal zone were 1.187,1.723,and 0.540,respectively.The mean values of H',D,and J'in the subtidal zone were 1.301,2.204,and 0.669,respectively,which were higher than those in the intertidal zone.Hyale schmidti,Gaetice depressus,and Pontogeneia littorea were the dominant species in the intertidal zone.In contrast,the dominant species in the subtidal zone were Mytilus coruscus,Hiatella orientalis,and Chlorostoma rustica.The results of cluster and nonmetric multidimensional scaling analyses showed that macrozoobenthos could be classified into four and three communities in the intertidal and subtidal zones,respectively.Compared with the previous reports of the adjacent areas,the surveyed area had a moderate species number with average abundance and biomass.