环境条件变化下滇池冬春季节浮游植物的演替特征  

Winter and Spring Succession of the Phytoplankton Community in Dianchi Lake under the Influences of Environment Change

作　　者：李莉杰 李国辉 李根保[1] LI Li-jie;LI Guo-hui;LI Gen-bao(State Key Laboratory of Freshwater Ecology and Biotechnology,Institute of Hydrobiology,Chinese Academy of Sciences,Wuhan 430072,P.R.China;The University of Chinese Academy of Sciences,Beijing 100049,P.R.China)

机构地区：[1]中国科学院水生生物研究所淡水生态与生物技术国家重点实验室,武汉430072 [2]中国科学院大学,北京100049

出　　处：《水生态学杂志》2020年第3期57-68,共12页Journal of Hydroecology

基　　金：FEBL国家重点实验室“全球气候变化与人为干预下蓝藻水华的区域特征与控制策略”项目(2016FBZ07)。

摘　　要：富营养化和气候变暖是影响浮游藻类结构组成以及物候学等特征的两大重要环境条件。为探讨在人为干预和全球变化影响下富营养化湖泊滇池浮游植物的演替特征,2017-2019年2个冬春季在滇池选择北(D1)、中(D2)、南(D3)3个采样点对浮游植物群落进行监测。研究结果表明,滇池浮游植物在冬春季呈现与以往不同的演替特征。第一、滇池在冬春季仍以蓝藻占优势,但优势种组成发生了变化。蓝藻中占主要生物量的是微囊藻,而且,惠氏微囊藻(Microcystis wesenbergii)取代铜绿微囊藻(Microcystis aeruginosa)占绝对优势。近20年来(2001-2019年),滇池冬春季微囊藻优势种经历了从铜绿微囊藻到绿色微囊藻(Microcystis viridis)再到惠氏微囊藻的转变。在水温较低的2-3月份,蓝藻生物量比例下降,绿藻和硅藻生物量比例上升,在此时期,香农威纳指数也相对升高。第二,束丝藻(Aphanizomenon)和鱼腥藻(Anabaena)的物候特征发生了改变。曾经春季的优势水华藻种束丝藻提前在秋季出现,且2018年秋季峰值较2017年约提前2周。2018年春季鱼腥藻在滇池北部发生了小型的水华,取代了往年发生束丝藻水华的现象,2019年春季鱼腥藻没有出现较高的生物量,但仍在春季达到峰值,其峰值约提前1周出现。本研究结果为揭示在全球变化和人为干预影响下湖泊冬春季节浮游植物群落演替特征及响应策略提供了基础数据支撑。Eutrophication and climate warming are affecting the structure and phenology of phytoplankton.In the past two decades,large scale cyanobacterial blooms have occurred frequently in Dianchi Lake,but water quality in Dianchi Lake is gradually improving due to pollution control.Since 2016,the water quality status of Dianchi Lake has improved from inferior Class V to Class V and the trophic level index(TLI)has decreased by 4.8%.In recent years,global warming has been strengthening and the average temperature of Dianchi Lake is clearly increasing,with the largest increase in winter.To explore the effects of human intervention and climate change on Dianchi Lake,seasonal succession of the phytoplankton community was investigated.Samples were collected at three sites in Dianchi Lake,D1(north),D2(central)and D3(south)during winter and spring of 2017,2018and 2019.Water environmental parameters were monitored simultaneously,including total nitrogen(TN),total phosphorous(TP),chlorophyll a(Chl-a),pH,conductivity and water temperature.Redundancy analysis(RDA)and Pearson correlation analysis were used to analyze the relationship between phytoplankton cell density and the environmental factors.The winter-spring successional characteristics of the phytoplankton community were found to be shifting.Cyanobacteria were still dominant in Dianchi Lake,but the dominant species had changed.Microcystis still made the largest contribution to cyanobacterial biomass,but M.wesenbergii replaced M.aeruginosa as the absolute dominant species.In the 20years from 2001to 2019,during winter and spring,the dominant species in Dianchi Lake shifted from M.aeruginosa to M.viridis and then to M.wesenbergii.From February to March,when water temperature is low,the relative biomass of cyanobacteria decreased,while those of Chlorophyta and diatoms increased.During this period,the Shannon Weiner index increased proportionately.The phenology of Aphanizomenon and Anabaena is also shifting.Aphanizomenon,formerly the dominant bloom-forming species in spring,appear

关 键 词：人为干预 全球气候变化 滇池 浮游植物 季节演替 

分 类 号：Q145[生物学—生态学]