太湖不同湖区真核微型浮游生物基因多样性的研究  

Genetic Diversity of Eukarytic Microplankton in Different Areas of Lake Taihu

作　　者：陈美军[1] 孔繁翔[1] 陈非洲[1] 邢鹏[1] 

机构地区：[1]中国科学院南京地理与湖泊研究所湖泊与环境国家重点实验室

出　　处：《环境科学》2008年第3期769-775,共7页Environmental Science

基　　金：国家自然科学基金项目(40671068,30600069);国家重点基础研究发展规划(973)项目(2002CB412300)

摘　　要：用DGGE（denatured gradient gel electrophoresis）和构建18SrDNA克隆文库2种方法对太湖不同湖区的真核微型浮游生物（0.8-20μm）多样性及组成结构进行了研究.DGGE结果表明,不同湖区真核微型浮游生物的DGGE指纹图谱存在明显差异,其中营养水平较低的东太湖和贡湖DGGE条带数最多,分别为23和24,香农多样性指数分别为3.135和3.178,而营养水平较高的梅梁湾和五里湖最少,均为18,香农多样性指数为2.890,表明营养水平较低湖区的多样性高于营养水平较高的湖区.克隆测序结果表明太湖中真核微型浮游生物种类丰富,占优势的主要是一些鞭毛藻、异养鞭毛虫、纤毛虫和真菌,而营养水平不同的梅梁湾、湖心、东太湖中真核微型浮游生物组成明显不同.在营养水平较高的梅梁湾,28.6%的OUT（operational taxonomicunit）属于异养鞭毛虫,另外隐藻、金藻分别占22.9%和14.3%;在湖心,金藻的比例最大,占25.7%,另外比较多的是异养鞭毛虫和隐藻,分别为20.0%和14.3%;而营养水平较低的东太湖各类纤毛虫所占比份最大,为26.8%,异养鞭毛虫较少,仅占4.9%,另外真菌含量较高,占12.2%.The methods of DGGE and cloning/sequencing were used to study the diversity and community structures of small planktons （0.8 - 20 μm） in different areas of Lake Taihu. DGGE indicated that there were markly various fingerprints in different areas and the diversities were higher in areas with low trophic status than those with relatively high trophic status. There were 23, 24 DGGE bands in East Taihu and Gonghu Bay, respectively （Shannon index were 3.135 and 3.178） and 18 bands in both Meiliang Bay and Wuli Bay （Both shannon index were 2.890）. The result of cloning/sequencing indicated that there was a high diversity of small planktons in Lake Taihu and most of them phototrophic flagellate, heterotrophic flagellate, ciliate and fungi. There were various community structures in the three different clone libraries. In Meilang Bay, 28.6 % OTUs（operational taxonomic unit）belonged to heterotrophic flagellate, followed by Cryptophyta （22.9 % ） and Chrysophyta （14.3%）. In Central Lake, 25.7% OTUs belonged to Chrysophyta, followed by heterotrophic flagellate （20.0%） and Cryptophyta （14.3 % ）. In East Taihu, ciliates were the dominant group and only a few heterotrophic flagellates （40.9 % ） were detected. In addition, fungi were relatively abundant （12.2%） in this area.

关 键 词：微食物网 真核微型浮游生物 DGGE 18SrDNA克隆文库 基因多样性 

分 类 号：X174[环境科学与工程—环境科学]