滤食性鱼类控藻过程中的浮游甲壳动物群落结构研究

Study on the community structure of planktonic crustaceans in the process of controlling algae in filter feeding fish

针对巢湖夏季蓝藻水华暴发,水体富营养化的现状,使用生态调控的方法对巢湖水体进行生态修复试验。于2022年6月—2023年5月在巢湖马尾河入湖区设置围网,对围网内A区域和围网外B区域的浮游甲壳动物和水环境因子进行采样调查,并结合二者利用Pearson相关性分析和RDA(redundancy analysis)方法分别探讨了浮游甲壳动物群落结构与环境变量的关系。经鉴定,试验区域A记录浮游甲壳动物17属30种,枝角类8属19种,桡足类9属11种;区域B记录浮游甲壳动物19属32种,枝角类10属21种,桡足类9属11种。区域A年均密度和生物量分别为(84.31±11.76)ind·L^(–1)和(1.08±0.16)mg·L^(–1),区域B年均密度和生物量分别为(88.18±17.83)ind·L^(–1)和(1.34±0.31)mg·L^(–1),区域B的年均密度和生物量均高于区域A。浮游甲壳动物按照体型大小和食性可划分4个功能群,分别为SCF(小型浮游甲壳动物滤食者)、MCF(中型浮游甲壳动物滤食者)、MCC(中型浮游甲壳动物捕食者)和LCF(大型浮游甲壳动物滤食者)。Pearson相关性分析结果显示,浮游甲壳动物功能群既受水环境因子影响同时又受其他功能群的影响。冗余分析(RDA)结果表明,在区域A,SD和NO3--N为影响浮游甲壳动物功能群时空变化的主要环境因子,在区域B,Chl-a和TN为影响浮游甲壳动物功能群时空变化的主要环境因子。

In response to the summer outbreaks of cyanobacterial blooms and eutrophication in Chaohu Lake,ecological restoration experiments were conducted on the Chaohu Lake water using ecological regulation methods.From June 2022 to May 2023,a purse seine was set up in the Mawei River inflow area of Chaohu Lake.Zoop-lankton and aquatic environmental factors were sampled and investigated in two distinct areas:Area A,inside the seine,and Area B,outside the seine.The relationship between the structure of the zooplankton crustacean com-munity and environmental variables was explored by using Pearson's correlation analysis and RDA method,re-spectively,in conjunction with both of them.A total of 17 genera and 30 species of zooplanktonic crustaceans,8 genera and 19 species of cladocerans,and 9 genera and 11 species of copepods were identified in Area A.The annual average density and biomass in Area A were(84.31±11.76)ind·L^(–1)and(1.08±0.16)mg·L^(–1),respectively.Nineteen genera and 32 species of zooplanktonic crustaceans,10 genera and 21 species of branchiopods,and 9 genera and 11 species of copepods were identified in Area B.The annual average density and biomass in Area B were higher,at(88.18±17.83)ind·L^(–1)and(1.34±0.31)mg·L^(–1),respectively.Planktonic crustaceans were categorized into four functional groups based on their body size and feeding habits,namely SCF(small copepods and cladocera filter feeders),MCF(middle copepods and claocera filter feeders),MCC(middle copepods and cladocera carnivora),and LCF(large copepods and cladocera filter feeders).The Pearson correlation analysis results showed that the functional groups of planktonic crustaceans were influenced by both water environmental factors and interactions with other functional groups.The results of redundancy analysis(RDA)showed that in Area A,SD and NO3--N were the main environmental factors affecting the spatial and temporal variation of the functional groups of zooplanktonic crustaceans,while in Area B,Chla and TN were the main environmental factors affecting the spatial and temporal variability of the functional groups of zooplanktonic crustaceans.