近三十年保安湖大型底栖动物群落结构演变及其构建机制  

Community succession and mechanisms of community assembly of macroinvertebrates over the past three decades in Lake Baoan

作　　者：刘洋[1,2] 李正飞 鲍少攀[1] 葛奕豪[1,2] 刘振元 谢志才 张君倩[1] Liu Yang;Li Zhengfei;Bao Shaopan;Ge Yihao;Liu Zhenyuan;Xie Zhicai;Zhang Junqian(Key Laboratory of Aquatic Biodiversity and Conservation of Chinese Academy of Sciences,Institute of Hydrobiology,Chinese Academy of Sciences,Wuhan 430072,P.R.China;University of Chinese Academy of Sciences,Beijing 100049,P.R.China)

机构地区：[1]中国科学院水生生物研究所,中国科学院水生生物多样性与保护重点实验室,武汉430072 [2]中国科学院大学,北京100049

出　　处：《湖泊科学》2023年第4期1397-1407,I0017-I0021,共16页Journal of Lake Sciences

基　　金：中国科学院水生生物研究所“生态文明”特色研究所服务性项目(Y85Z0511);湖北省生物多样性本底调查观测评估项目(SZZC-2021-0155)联合资助。

摘　　要：保安湖是江汉湖群的一个典型浅水湖泊。近几十年来,随着经济的快速发展,保安湖面临多重人类压力影响,富营养化问题日趋严重。历史上曾开展过数次的保安湖底栖动物调查,但有关群落结构的长期变化及其驱动机制改变的认知仍为空白。本研究基于30余年(19862019)的多次调查数据,探索保安湖底栖动物的群落演变规律及其群落构建机制。研究共记录保安湖底栖动物5门10纲25目49科110属170种(历史记录154种,现场调查51种)。总物种数由1992年的107种降为2019年的51种;平均密度由1992年的433 ind./m 2增加到2019年的2177.6 ind./m 2;平均生物量由2001年的160.6 g/m 2降低为2019年的26.7 g/m 2。优势种在1987年有寡毛类、水生昆虫和软体动物多个类群,其后逐步演变为现阶段少数几种耐污的寡毛类和摇蚊类,如霍甫水丝蚓(Limnodrilus hoffmeisteri)、中国长足摇蚊(Tanypus chinensis)、红裸须摇蚊(Propsilocerus akamusi)等,而多年生大型软体动物衰退明显。PERMANOVA和SIMPER分析结果表明,2001和2019年底栖动物群落结构差异显著,不同时期特征种差异较大。近20年间,底栖动物群落构建机制发生变化,主要驱动力由环境过滤(2001年)转变为中性过程(质量效应)(2019年)。现阶段(2019年),不同季节的群落结构存在一定差异,春冬两季的物种数、密度以及生物量均大于夏秋两季,但不同季节的特征种相似。同时,群落构建的关键因子及驱动机制在不同季节间也存在一定差异,除秋季外,其他季节的空间因子解释率均大于环境因子解释率。As a typical shallow lake along the middle-lower reach of the Changjiang River,Lake Baoan,located in the Lake Jianghan District,has been suffered from multiple anthropogenic pressures for several decades,leading to severe eutrophication.As a consequence,its macroinvertebrate fauna has experienced biodiversity decline and compositional change.Our understanding of the community succession associated with community assembly shift,however,remains limited,although several investigations have been carried out in this lake.Here,we explored community succession and mechanisms of macroinvertebrate community assembly based on combined datasets of historical records and field investigations in 2019-2020.A total of 170 taxa(154 from historical records and 51 in the field investigations)were recorded,belonging to 49 families and 110 genera.Species richness declined significantly over the recent three decades,from the peak value 107 in 1992 to 51 now,but aquatic insects were still the dominant groups at various times.The variation trend of average density increased,from the peak value 433 ind./m 2 in 1992 to 2177.6 ind./m 2 now,while average biomass was in the opposite trend,from 160.6 g/m 2 in 2001 to 26.7 g/m 2 now.The dominant species were changed from multiple groups comprising oligochaeta,aquatic insects and mollusks to those highly pollution-tolerant and widespread species,including Limnodrilus hoffmeisteri,Tanypus chinensis and Propsilocerus akamusi,while long-life and large mollusks communities deteriorated gradually.In addition,the PERMANOVA and SIMPER analyses revealed significant variations in the community structure of macroinvertebrates and characteristic species among the different years.Variance partitioning analysis showed that in the recent 20 years,the mechanisms of the community assembly had changed,and spatial processes(mass effect)had stronger effects on macroinvertebrate community structure than environmental filtering processes.RDA/CCA results demonstrated that environmental variables(total nitrogen and

关 键 词：浅水湖泊 保安湖 富营养化 大型底栖动物 群落演变 驱动机制 

分 类 号：Q958.8[生物学—动物学]