山东半岛南部中国明对虾放流前后渔业资源群落结构

Community Structure of Fishery Resources in the Bays of Southern Shandong Peninsula Pre-and Post-releasing of Chinese Shrimp Fenneropenaeus chinensis

根据2010年在山东南部各海湾分别就中国明对虾放流前、后渔业资源进行了调查,共鉴定渔业资源种类72种,对虾放流前、后渔业资源单位网次渔获量分别为13.4、14.2kg/h。一些生命周期短、个体小、资源更新快的小型低质鱼类或无脊椎动物,成为目前山东半岛海湾内渔业资源的主体。通过聚类分析、多维排序尺度、丰度生物量比较曲线分析,结果表明,渔业资源种类若以20%的相似性来划分,可划分为2个组群,生物群落处于中度及以上程度干扰。中国明对虾放流后渔业资源丰富度指数较放流前有所降低,而多样性指数和均匀度指数却高于放流前。该海域对虾放流后吸引了大量花鲈洄游至此索饵,对放流幼对虾成活造成一定威胁,且部分渔业资源优势种与对虾存在着食物竞争关系。

Community structure of fishery resources was studied in the bays of southern Shandong peninsula pre-and post-releasing of Chinese shrimp Fenneropenaeus chinensis by the bottom trawl surveys in 2010,in which there were 72 species collected from the two trawl surveys.The mean relative catches of the shrimp was found 13.4 kg/h pre-releasing,and 14.2kg/h post-releasing.The low-value small fishes and invertebrates with short life span and generation were the predominant fishery resources in the bays of southern Shandong peninsular.CLUSTER analysis,Multi-Dimensional scaling,and Abundance biomass comparison revealed that macrobenthic communities were divided into two groups depending on the similarity level of 20%.Macrobenthic communities were disturbed on either moderate or heavy level.Species richness of Chinese shrimp was lower pre-releasing than post-releasing,while the shrimp showed higher Shannon diversity index and evenness index pre-releasing than post-releasing.The Chinese shrimp released into the bay were threaten to survival by large population of sea perch aggregating to feed and by to some extent competition with food from the dominant species.