滇池不同湖区浮游植物群落结构特征及与环境因子的关系

CHARACTERISTICS OF PHYTOPLANKTON COMMUNITIES STRUCTURE AND CORRELATIONS WITH ENVIRONMENTAL FACTORS IN DIFFERENT AREAS OF DIANCHI LAKE

为了解滇池不同湖区浮游植物群落结构特征及其与环境因子的关系。基于2021年1-12月滇池浮游植物和部分水质理化指标的监测数据,分析研究了浮游植物群落结构特征及其影响因子。结果表明:1)滇池草海、外海两个湖区的水质状况、浮游植物群落结构存在明显差异。综合评价认为,草海水质状况优于外海。绿藻在两个湖区种类数均最多,蓝藻门微囊藻属在外海全年和草海夏秋季占绝对优势,硅藻门小环藻属、直链藻属会在秋冬季的草海中形成优势;同时草海浮游植物种属数、生物多样性指数、生物量显著高于外海,而细胞密度显著低于外海。2)同一湖区浮游植物群落结构特征和生物多样性指数(H)存在不同程度的季节变化。在细胞密度上,草海、外海藻类细胞密度夏秋季较高,冬春季较低。在生物量上,草海藻类生物量春夏季较高,秋冬季较低;外海夏秋季高于冬春季。在生物多样性上,草海春冬季高于夏秋季,而外海秋冬季高于春夏季。同时外海浮游植物细胞密度和生物量呈现出南低北高的态势。3)影响草海、外海浮游植物群落结构的环境因子有所不同,但水温的季节变化是导致这两个湖区浮游植物群落结构季节变化的主要环境因子。

In order to understand the structural characteristics of phytoplankton communities and correlations with environmental factors in different areas of Dianchi Lake.Based on the monitoring data of phytoplankton and water quality indicators in Dianchi Lake from January to December 2021,this paper analyzes the characteristics of phytoplankton communities structure and its influencing factors.The results showed that there were significant differences in water quality and phytoplankton community structure between Caohai and outer sea in Dianchi Lake.The comprehensive evaluation shows that the water quality of Caohai is better than that of Dianchi outer Lake.Among the algae species in Dianchi Lake,Chlorophyta accounts for the largest proportion.Cyanobacteria Microcystis is absolutely dominant in Dianchi outer Lake all year round.Melosira and Cyclotella will form dominance in Caohai in autumn and winter.The phytoplankton communities structure characteristics and biodiversity index(H)in the same lake area have different degrees of seasonal variations.In the same time,the algae densities and biomass in the northern part are more than those in the southern part of Dianchi outer Lake.The environmental factors that affect the phytoplankton communities structure in Caohai and Dianchi outer are different,but the seasonal change of WT is the main environmental factor that leads to the seasonal variations of phytoplankton community structure in Dianchi Lake.