鉴江口潮间带春季底栖双壳贝类多样性与群落结构特征初探

Preliminary study on the diversity and community structure characteristics of benthic bivalves during spring in the intertidal zone of Jianjiang Estuary

为探究鉴江口潮间带底栖双壳贝类资源现状、多样性和群落结构特征,评估其受扰动状态。基于2022年5月鉴江口潮间带5个断面的底栖双壳贝类调查数据,分析了其种类组成、丰度、生物量和物种多样性指数及生态功能组的组成模式,利用聚类分析和非度量多维尺度分析法(nMDS)探究了其群落结构特征,并利用物种丰度/生物量比较曲线(ABC曲线)揭示了其受扰动状况。本研究共采集到双壳贝类25种,隶属于8科17属,其中帘蛤科种类占比最高(44.0%),为11种;蚶科次之,共5种(20.0%);其他种类贝类物种占比较少,未发现曾经盛产于鉴江口的尖紫蛤(Sanguinolaria acuta)。优势种为直竹蛏(Solen strictus)、文蛤(Meretrix meretrix)、等边浅蛤(Gomphina aequilatera)、粗肋蛤蜊(Mactra aphrodina)和丽文蛤(Meretrix lusoria)。根据物种对扰动的敏感度,可以将鉴江口潮间带双壳贝类分为敏感种、不敏感种和二阶机会种3个生态组,其中敏感种在种类和数量方面均占绝对优势。等级聚类和nMDS分析结果表明鉴江口潮间带底栖双壳贝类可以划分为2个亚群,其中断面S1—S4构成1个亚群,断面S5单独构成1个亚群。ABC曲线结果表明鉴江口潮间带底栖双壳贝类群落受到中等扰动。本研究可为鉴江口贝类资源利用和保护提供理论依据。

To explore the current resources,diversity,and community structure characteristics of intertidal bivalves in the Jianjiang Estuary and evaluate the disturbed state of their communities.Based on the survey data of benthic bivalves from five sections of intertidal zones in the Jianjiang Estuary in May 2022,the species composition,abundance,biomass,species diversity index,and patterns of ecological functional groups of benthic bivalves were analyzed.Subsequently,cluster analysis and nonmetric multidimensional scaling scale analysis(nMDS)were used to explore the characteristics of their community structures.Finally,the species abundance/biomass comparison curve(ABC curve)was used to reveal the disturbance status of the benthic bivalve community in the Jianjiang Estuary.This study recorded a total of 25 bivalve species in the intertidal zone of the Jianjiang Estuary,belonging to eight families and 17 genera,of which 11 species belonged to the family Veneridae,accounted for the highest proportion(44.0%),followed by the family Arcidae,with a total of five species(20.0%);other bivalve species accounted for a relatively small proportion,and no Sanguinolaria acuta that once abundant have been discovered.The dominant species were Solen strictus,Meretrix meretrix,Gomphina aequilatera,Mactra aphrodina,and Meretrix lusoria.The sampled bivalves in the intertidal zone of the Jianjiang Estuary can be divided into three ecological groups based on the sensitivity of species to disturbance:sensitive,indifferent,and second-order opportunistic species,of which the sensitive species have absolute advantages in terms of richness and abundance.Hierarchical cluster analysis and nMDS results show that benthic bivalves in the intertidal zone of the Jianjiang Estuary can be divided into two subgroups,of which Sections S1–S4 form a subgroup and Section S5 forms a subgroup alone.The ABC curve results revealed that the benthic bivalve community was moderately disturbed in the intertidal zone of Jianjiang Estuary.The results of this study can provide a theoretical basis for the utilization and protection of bivalve resources in the Jianjiang Estuary.