连云港南部近岸海域游泳生物群落结构调查

Study on the Changes of Community Structure of Nekton in the Southern Coastal Waters of Lianyungang

于2016—2020年春季,对连云港南部近岸海域游泳生物种类组成、资源密度、种类多样性和群落结构进行了调查。结果表明,5年间,连云港南部近岸海域共捕获游泳生物85种,其种类由55下降到39种,资源质量密度由229.57上升到1048.94 kg/km^(2)。Shannon-wiener多样性指数为0.19~3.95,Pielou均匀度指数为0.05~0.91,Margalef种类丰富度指数为0.59~3.56。采用聚类分析法,对各年度调查站位的游泳生物群落结构进行分析,将全部站位分为2个站位组,其中站位组1主要为2017年南部近岸海域的站位,站位组2为其余年份的站位;站位组间的典型种和分歧种主要为戴氏赤虾(Metapenaeopsis dalei)、口虾蛄(Oratosquilla oratoria)、三疣梭子蟹(Portunus trituberculatus)和赤鼻棱鳀(Thrissa kammalensis)等。结构冗余度结果表明,2016—2020年春季群落除2016和2019年有2个响应单元外,其余年份均只有1个;群落结构冗余度水平较低,游泳生物群落结构稳定性相比较差。应用GAM模型结果显示,资源质量密度与深度和温度有关联。

In order to gain an in-depth understanding of the differences in the composition of nekton in the southern coastal waters of Lianyungang in spring,the paper based on the survey data of the nekton in the southern coastal waters of Lianyungang in spring for five consecutive years from 2016 to 2020,the composition of biological species,resource density,species diversity and community structure were studied.The results showed that 85 species of nekton were caught in the past five years.From 2016 to 2020,the species of nekton in the southern coastal waters of Lianyungang dropped from 55 to 39,and the resource amount increased from 229.57 kg/km^(2) to 1048.94 kg/km^(2).The Shannon-wiener diversity index(H')is between 0.19 and 3.95,the Pielou uniformity index (J) is between 0.05 and 0.91,and the Margalef species richness index(d)is between 0.59 and 3.56.The community structure of nekton at each annual survey station was analyzed by cluster analysis,and all stations could be divided into two station groups,of which station group 1 was mainly the stations in the southern coastal waters in 2017,and station group 2 was the stations in other years.The typical and divergent species among the stations groups were mainly Metapenaeopsis dalei,Oratosquilla oratoria,Portunus trituberculatus and Thrssa kammalensis and so on.The analysis of structural redundancy results showed that there were 2 response units in 2016 and 2019,and only 1 response unit in 2017,2018,and 2020.The level of community structure redundancy was low,and the structural stability of nekton was relatively poor.According to the GAM model,resource weight density is related to depth and temperature.