滇池藻类生物量时空分布及其影响因子  

THE SPATIO-TEMPORAL DISTRIBUTION OF ALGAL BIOMASS IN DIANCHI LAKE AND ITS IMPACT FACTORS

作　　者：万能[1,2] 宋立荣[1] 王若南[3] 刘剑彤[1] 

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]中国科学院研究生院,北京100049 [3]云南大学生命科学学院,昆明650091

出　　处：《水生生物学报》2008年第2期184-188,共5页Acta Hydrobiologica Sinica

基　　金：中国科学院知识创新工程重要方向性项目(KZCX2-YW-426);国家重点基础研究发展规划项目(2002CB412306)资助

摘　　要：以滇池全湖选取的40个样点,从2001年9月到2002年8月对全湖水体中的叶绿素a的含量每月进行调查,对浮游植物的群落组成和细胞数每两个月进行分析。结果显示,叶绿素a的含量(月均值)从2002年1月的0.015mg/L增加到2002年8月的0.10mg/L呈现明显的上升趋势,水体温度也从1月的10℃上升到8月的28℃;叶绿素a含量的全湖均值则显示出南部水域低,北部水域高的态势,其中又以1号位点最高。滇池地区常年盛行的西南风导致藻类向北的水平运动加强对这一结果的形成有着重要的影响。种群优势度的结果也显示出蓝藻(Cyanobacterium)的优势度高达100%,其中以铜绿微囊藻(Microcystis aeruginosa)又最为常见。但在2002年3月,束丝藻成为了优势种群,表明滇池藻类的优势种群存在明显的季节演替。研究结果同时表明,在各项理化指标当中,叶绿素a(Chl.a)与水温(WT)、总氮(TN)及化学需氧量(CODMn)有极显著相关,Pearson相关系数分别为0.736、0.970和0.929,p<0.01。结果表明,氮已经取代磷成为滇池藻类生长的营养限制因子,表征有机污染物程度的CODMn也已成为藻类生物量的主要相关因子,由此可见滇池的富营养化程度极高,尤其是有机污染物浓度。Dianchi Lake is a typical plateau, unstratificated, eutrophic lake in southwest of China. It has been seriously polluted in the past decades. And it had not been investigated in the whole lake for phytoplankton since 1980s. Thus, a project was carried out to find out what happened to the phytoplankton biomass and its regime dominance in the lake now. In this study, Chlorophyll α （ Chl. α ） had been monthly investigated according to the national standard method at 40 sites in Dianchi Lake from September,2001 to August, 2002. Cell density and phytoplankton species composition had been investigated bimonthly as well. The results showed that Chl. a increased from 0.015mg/L to 0.10mg/L （monthly average values） during January to August,2002. Correspondingly, water temperature increased from 10℃ to 28℃. Chlorophyll concentrations of the south sites were lower than the north ones. Site one had the highest chlorophyll a value in all sites. We concluded that the southwester prevailing over the Dianchi Lake played a very important role. The horizontal movement of phytoplankton should be wind-induced. The water blooms mainly composed by cyanobacterial species. The percentage sometimes reaches to 100%. And Microcystis aeruginosa was the most common species. But in the spring of 2002, the dominance species was changed. Aphanizomenon spp. became dominant （69 % ） in March. It showed an obvious evidence for the seasonal succession. Moreover, the investigation indicated that the Pearson Correlation were high significant between chlorophyll a and water temperature （0.736, p 〈 0.01 ）, total nitrogen （0. 970, p 〈 0.01 ） and chemical oxygen demand （0.929, p 〈 0.01 ）. Therefore, we concluded that phosphorus was no longer the limited nutrition factor in Dianchi Lake to phytoplankton growth, nitrogen has taken the place. CODM,, which is considered the token of organism population level, become the main chemical factor affecting the algal biomass. All the results indicate that Dianchi Lake is extreme

关 键 词：生物量 叶绿素α 时空分布 相关性 

分 类 号：X173[环境科学与工程—环境科学]