兴凯湖当壁镇湖区夏季浮游植物群落结构变化

2009年夏季对兴凯湖当壁镇湖区浮游植物群落结构进行研究。结果表明,兴凯湖当壁镇湖区浮游植物共计7门41种属,绿藻、硅藻的种类为主,分别占39.0%、24.4%;数量、生物量均值分别为192.97×104ind.L-1、2.4605mg.L-1,硅藻的数量、生物量最多（147.47×104ind.L-1、2.2818 mg.L-1）。优势种中硅藻、绿藻、蓝藻、黄藻门的种类均有,分别为扭曲小环藻（Cyclotella comta）、颗粒直链藻最狭变种（Melosira granulata）;普通小球藻（Chlorella vulgaris）、湖生卵囊藻（O觟cystis lacustris）;小形色球藻（Chroococcus minor）以及黄丝藻（Tribonemnsp.）。调查湖区,浮游植物的多样性较丰富（H＇均值2.09,J均值0.56）。比较2001年研究结果,兴凯湖当壁镇湖区夏季浮游植物的种类组成、数量变化不大;硅藻、隐藻优势种的比例下降,绿藻增加,优势种中丝状藻类比例增加;浮游植物的生物量有所上升,调查湖区鱼产潜力有升高趋势。

Variations of Phytoplankton Community Structure in Dangbi Town of Xingkai Lake in Summer

Variations of phytoplankton community structure in Dangbi Town of Xingkai Lake was investigated in July 2009.The results showed that the phytoplankton assemblage was composed of 41 species in total,belonging to seven taxonomic groups.Chlorophyta were represented by the highest percentage of taxa（39.0%） followed by Bacillariophyta（24.4%）.The average cell density of phytoplankton was 192.97×104ind·L-1 and the average biomass was 2.4605mg·L-1.Bacillariophyta were represented by the highest cell density（147.47×104ind·L-1） and biomass（2.2818mg·L-1）.Dominant species concluded Bacillariophyta,Chlorophyta,Cyanophyta,Xanthophyta.Dominant species were Cyclotella comta,Melosira granulate,Chlorella vulgaris,Ocystis lacustris,Chroococcus minor and Tribonemn sp...The diversity of phytoplankton in that lake was abundant（the value of H’ was 2.09;the value of J was 0.56）.Over time,there was little change in dominant species and large change in species composition,cell density and biomass.The later time was the lower X index was.Compared with data between 2001 and 2009,species composition and cell density of phytoplankton in Xingkai Lake declined slightly.Dominant species of Bacillariophyta and Cryptophyta declined and dominant species of Chlorophyta increased.The percentage of filamentous algae in dominant species was increasing.In addition,the biomass of phytoplankton rose in Xingkai Lake.At the same time,fish production potential tended to increase in Dangbi Town of Xingkai Lake.There were two purposes of this study.One purpose was to accumulate basic data of phytoplankton resources in Dangbi Town of Xingkai Lake.The other purpose was to provide reference data for fish feeding habits that was studied by co-workers in Xingkai Lake.