浙江瓯飞围填海区渔业资源优势种生态位分析

生态位体现了物种在群落中利用资源的能力及种间关系,在生态学研究中具有重要的意义。为探求浙江瓯飞围填海区渔业资源群落结构的形成和影响因素,于2014年5月对浙江瓯飞围填海区渔业资源进行调查。通过相对重要性指数确定资源群落优势种,结合非度量多维标度法和Bray-Curtis相似性分析法对优势种的生态位宽度、生态位重叠值进行分析,并以典范对应分析(CCA)研究生态位分化状况。结果表明:(1)该海域优势鱼种为12种,与围填海工程开始前(2007年)相近,主要优势鱼种为白姑鱼;(2)优势种生态位变化范围为0.31~2.32,生态位较宽的有白姑鱼、皮氏叫姑鱼、银鲳、口虾姑、三疣梭子蟹、棘头梅童鱼和龙头鱼,优势种间的生态重叠值为0.01~0.95,差异较大,其中班与绿鳍红娘鱼的重叠值最高,为0.95,CCA分析结果显示优势种生态位的宽度、优势种间的重叠值与物种的功能类群及生境状况密切相关,并非简单正相关;(3)影响围填海区渔业资源物种分布的最主要因子是悬浮物和叶绿素,其次为p H、水温和盐度,溶解氧的影响最小,这些环境因素综合解释了此区域渔业资源群落种类组成59.0%的总变异。

Niche analysis of dominant species of fishery resources in Zhejiang Oufei reclamation area

Ecological niche can be used as an indicator to symbolize the resources utilization capability of certain groups of related species and inter-species relationship, and it's essential for ecology research.A survey to determine the fishery in the Zhejiang Oufei reclamation area was conducted in May 2014. The index of relative importance (IRI) was measured to determine the dominant species of fish assemblage. The niche breadth and overlap of the dominant fish species were analyzed with the Bray-curtis similarity clustering and non-metric multidimensional scaling(MDS) analysis,and the differentiation of the niche was studied with canonical correspondence analysis(CCA),aiming to approach the community structure of fishery resources and related influencing factors in the area.The results showed that:(1)There are 12 dominant species,the main dominant species were Argyrosomus argentatus Houttuyn similar with that in 2007.(2)The niche breadth index varied from 0.31 to 2.32. Argyrosomus argentatus Houttuyn, Johnius belangerii,Pampus argenteus, Squilla orarotia,Portunus trituberculatus, Collichthys lucidus and Harpadon nehereus had large niche breadths.Niche overlaps varied from 0.01 to 0.95, Clupanodon punctatus and Lepidotrigla scaled searobins had a niche overlap value about 0.95. CCA results showed that the niche breadth and overlap of dominant species were closely related with the functional groups of species and habitat conditions, and they do not have a simple positive correlation. (3) Suspended matter had more important influence on the species spatial distribution than water temperature, salinity, pH and chlorophyll a, and the species spatial distribution was less affected by dissolved oxygen.These factors could account for 59% of the species variation.