云南杞麓湖浮游植物的群落特征及相关因子的研究

The Community Structure of Phytoplankton and Its Relationship to Environmental Factors in Qilu Lake,Yunnan

2020年1—12月,在杞麓湖选取了6个标准样点,调查浮游植物的群落组成和关键理化因子的时相变化,结合生物和非生物因子,分析杞麓湖浮游植物群落结构的演替规律及浮游动物对浮游植物群落结构的影响,揭示该湖浮游植物群落周年演替的动力因素。结果表明:杞麓湖属于高氮低磷的富营养化水体,其关键理化因子有明显的时相变化;参考近10年的调查数据,发现以丝状蓝藻占主导地位的浮游植物群落的相对丰度和相对生物量呈下降趋势,并且浮游植物群落结构存在明显的季节性演替,夏季(6—8月份)稳定性较低,处于蓝藻爆发阶段。优势物种的时相分布可分为水华束丝藻主导时期和阿氏浮丝藻主导时期,浮游植物受关键理化因子和浮游动物的共同影响。

In January and February 2020,6 sampling sites were selected in Qilu Lake to investigate the community composition of phytoplankton and temporal variation of key physicochemical factors.Combined with biotic and abiotic factors,the succession of phytoplankton community structure in Qilu Lake and the influence of zooplankton on phytoplankton community structure were analyzed,and the dynamic factors of annual succession of phytoplankton community in Qilu Lake were revealed.The results showed that Qilu Lake was a eutrophic water body with high nitrogen and low phosphorus,and its key physicochemical factors presented obvious spatial variations.Comparing with survey data from the last 10 years,the relative abundance and biomass of the phytoplankton community dominated by filamentous cyanobacteria displayed a decreasing trend in Qilu Lake.The phytoplankton community structure showed an obvious seasonal succession.Summer(June–August)is less stable,with cyanobacterial bloom.According to the temporal distribution characteristics of dominant species,it could be divided into the Aphanizomenon flos-aquae and Planktothrix agardhii dominant period.The phytoplankton community was influenced by both key physicochemical factors and zooplanktons.