【摘要】 2010年对洞庭湖6个典型断面进行了浮游藻类生物调查,共鉴定出7门72属(种),浮游藻类的密度范围在67.2×104～161.9×104cell·L-1;各典型断面间浮游藻类组成以硅藻和隐藻占优势,藻类群落结构存在着明显的差异。藻类Margalef指数及Shannon-Wienner指数范围分别为3.64～4.03和3.03～3.24,水体水质状况良好。应用CANOCO4.5软件对获得的浮游植物数据和环境因子数据进行典范相关分析(CCA),作出物种与环境因子关系的二维排序图。结果显示,典型断面藻类群落分布受水环境因子影响较为明显,整体上,DO和TN是影响洞庭湖典型断面藻类物种分布格局的主要因素。更多还原

【Abstract】 This research was performed in 2010 at 6 sections of Dongting Lake,aiming to investigate the algal species.A total of 72 kinds of algal genera(species) belonging to 7 phyla were identified.The algae had an abundance ranging from 67.2×104 cells·L-1 to 161.9×104 and obviously different across the sampling sections in the three seasons,for example,Nanzui had the highest and Wanzi Lake had the lowest mean algal abundance across the 6 sampling sections.The algal community was dominated by Bacillariophyta and Cryptophyta,and significant difference was found on algal composition across 6 sampling sections.Overall,Margalef values varied from 3.64 to 4.03,while Shannon-Wienner varying from 3.03 to 3.24,both showing well water quality.Canonical correspondence analysis(CCA) was applied to explore the relationship between algal species and environmental parameters by CANOCO 4.5.The species-environment biplots were drawn based by the result of CCA.The result showed that dissolved oxygen(DO) and total nitrogen(TN) were the most important factors influencing the distribution of algal species across the 6 typical sections,for example,Cymbella sp.,Merismopedia sp.,Navicula sp.,Nitzschia sp.,and Gyrosigma sp.were chiefly influenced by DO,while Melosira sp.,Cyclotella sp.,Cryptomonas sp.,Euglena sp.,Peridinium sp.,and Stephanodiscus sp.were chiefly influenced by TN,and Ankistrodesmus sp.,Scenedesmus sp.and Synedra sp.were chiefly influenced by both DO and TN.Besides these,the other factors just like biochemical and chemical oxygen demand,total phosphorus(TP) and pH were also important to the algal species.更多还原