摘要
云南抚仙湖是我国典型的高原深水湖泊,为揭示该湖浮游植物群落特征及其对生态系统变化的响应,2005年6～7月对浮游植物及环境因子进行了调查。调查期间共采集浮游植物80种,隶属于7门32科56属,以绿藻、蓝藻和硅藻为主,种类数绿藻(46.0%)>蓝藻门(25.0%)>硅藻门(15.0%),密度绿藻(61.6%)>硅藻(16.1%)>蓝藻(9.1%)。群落平均密度为87.58×104ind./L,转板藻(Mougeotiasp.)占绝对优势,其相对密度为35.9%。在水平分布上,浮游植物平均密度北区大于南区(P<0.05),沿岸区大于湖心区(P<0.01)。在垂直分布上,浮游植物分层明显,主要分布在0～30 m水层,不同水层绿藻均占绝对优势。环境分析表明:抚仙湖浮游植物密度水平分布主要受营养盐的影响,而垂直分布主要受物理因子的影响。不同时期的调查结果比较表明,抚仙湖浮游植物种类数和密度呈增长趋势,与水体营养水平升高有关。20世纪90年代中期以来,大型丝状藻类转板藻发展成为绝对优势种,与其较强的竞争优势及太湖新银鱼摄食引发的下行效应有关。
Fuxian Lake is a typical deep plateau lake located in Yunnan Province,China.In order to describe phytoplankton community of the Fuxian lake and its response to ecological changes,investigation on phytoplankton community and its related environmental factors were carried out from June to July in 2005.there existed 56 genera,32 families and 7 phyla in totally eighty phytoplankton species from the survey.The dominant taxa were Cyanophyta,Chlorophyta and Bacillariophyta,with the species number in the order of Cyanophyta（46.0%） 〉 Chlorophyta（25.0%） 〉 Bacillariophyta（15.0%） and quantity in the order of Cyanophyta（61.6%） 〉 Bacillariophyta（16.1%） 〉 Chlorophyta（9.1%）.The abundance of phytoplankton community was 87.58×104 ind./L,and the dominant species was Mougeotia sp.with a relative abundance of 35.9%.The average density of phytoplankton community was higher in Northern lake than that in Southern lake（P〈0.05）,and the average density of phytoplankton community in littoral area is higher than that in lake centre area（P〈0.01）.The vertical distribution of phytoplankton demonstrated a significant stratification in the open waters.Phytoplankton mainly accumulated in 0-30 m depth,and Cyanophyta dominated the community in density from top to the bottom in lake.Environmental analysis indicated that the horizontal distribution of phytoplankton density is controlled by the nutrients while its vertical distribution is determined by the physical variables.The survey results in different periods showed the increased trends both on the species number and on the density of phytoplankton in Fuxian Lake.It is the increased nutrient levels of the lake that cause the change of phytoplankton community.Large filamentous Mougeotia sp.has growed as the dominant species of the community since the mid-1990s,due to its competitive advantages and the top-down control of zooplankton by Neosalanx taihuensis.
出处
《生态学报》
CAS
CSCD
北大核心
2009年第10期5376-5385,共10页
Acta Ecologica Sinica
基金
国家973计划资助项目(2008CB418005)
湖泊与环境国家重点实验室开放基金资助项目
国家水体污染控制与治理重大专项资助项目(2008ZX07101-007-05)
关键词
藻类
群落结构
空间分布
环境因子
深水湖泊
algae
community structure
spatial distribution
environmental factors
deep lake
