中文摘要：

2010年1、5、9月对洞庭湖6个典型断面进行了底栖动物调查,共鉴定出3门40属（种）,底栖动物的密度范围在16~320 ind/m2;各典型断面间底栖动物组成以软体动物占优势,底栖动物群落结构存在着明显差异.底栖动物Shannon-Wienner指数及Margalef指数范围分别为0.95~2.22和0.75~1.99.对获得的底栖动物数据和环境因子数据进行典范相关分析（CCA）.结果显示,典型断面底栖动物群落分布受水环境因子影响较为明显,整体上,pH值和DO是影响洞庭湖典型断面底栖动物种类分布格局的主要因素.

英文摘要：

This research was performed in 2010 at 6 sections of Dongting Lake,aiming to investigate the structure of macroinvertebrate communities.A total of 40 macroinvertebrate taxa belonging to 3 phyla were identified.The macroinvertebrate abundance ranged from 16 to 320 ind/ m2 and obviously different across the sampling sections in the three seasons,for example,Nanzui had the highest and Muping Lake had the lowest mean macroinvertebrate abundance across the 6 sampling sections.The macroinvertebrate community was dominated by Mollusca,and significant difference was found on macroinvertebrate composition across 6 sampling sections.Overall,Shannon-Wienner diversity varied from 0.95 to 2.22,while Margalef diversity varying from 0.75 to 1.99.Canonical correspondence analysis（CCA） was applied to explore the relationship between macroinvertebrate community and environmental parameters.pH and dissolved oxygen（DO） were the most important factors influencing the distribution of macroinvertebrate species across the 6 typical sections,for example,Bellamya puificata,Bellamya aeruginosu,Semisulospira cancellata,Corbicula fluminea,Alocinma longicornis,Aulodrilus prothecatus and Gammarus were chiefly influenced by pH,while Tendipes plumosus,Stictotenddipes sp.,Branchiura sowerbyi,Limnodrilus hoffmeisteri and Limnodrilus grandisetosus were chiefly influenced by DO,and Psectrocladius was chiefly influenced by both pH and DO.Furthermore,the other factors just like biochemical and chemical oxygen demand,total phosphorus（TP）,total nitrogen（TN） and ammonia nitrogen（NH3-N） were also important to the macroinvertebrate species.