太湖表层底泥中产毒蓝藻群落结构和种群丰度的时空变化  

Temporal-spatial changes in community structure and abundance of microcystin-producing cyanobacteria in surface sediments of Lake Taihu

作　　者：李大命[1,2,3] 于洋[2] 张民[2] 阳振[2] 孔繁翔[2] 

机构地区：[1]江苏省淡水水产研究所,南京210017 [2]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,南京210008 [3]中国科学院研究生院,北京100039

出　　处：《环境科学学报》2012年第11期2827-2835,共9页Acta Scientiae Circumstantiae

基　　金：国家重点基础研究发展计划(No.2008CB418000)~~

摘　　要：为了研究太湖底泥中产毒蓝藻群落结构和种群丰度的时空变化,分别于2010年冬季(2月)、春季(4月)和夏季(6月)采集太湖不同湖区底泥样品,应用基于mcyA基因的聚合酶链式反应-变性梯度凝胶电泳(PCR-DGGE)和实时定量PCR(QPCR)技术分析底泥样品.结果表明,产毒蓝藻在太湖底泥中分布广泛,其群落结构和种群丰度存在空间和季节差异性:不同湖区间群落组成相似性系数变化范围为67%～97%;冬季、春季和夏季底泥中产毒蓝藻群落结构的香农多样性指数变化范围分别为2.774～3.392、1.649～2.619和0.681～1.996,呈逐渐下降趋势;且香农多样性指数与样品中优势基因型所占比例呈极显著负相关(p<0.01,r=-0.95);从冬季到夏季,底泥中蓝藻复苏进入水体中,产毒蓝藻种群丰度逐渐降低.底泥中产毒蓝藻群落结构和种群丰度的动态变化与温度、光照、溶解氧、电导率和pH值密切相关.In order to investigate the temporal-spatial changes in community structure and abundance of microcystin-produeing cyanobacteria in surface sediments （0 ～ 3 cm） of Lake Taihu, Polymerase Chain Reaction-Denaturing gradient gel electrophoresis （PCR-DGGE） was used to investigate the community structure of potential toxic cyanobacteria and quantitative real-time PCR （QPCR） was used to analyze the dynamics of this population based on the presence of the mcyA gene in sediment samples. Sediment samples were collected in eight locations in winter （February） , spring （April） and summer （June） of 2011. The results revealed that toxic cyanobaeteria were widely distributed in all sediment samples; PCR-DGGE profile patterns showed that there were temporal-spatial changes in community structure of toxic cyanobacteria and the community composition similarity varied from 67% to 97% in the composition of rncyA genotypes in sediment samples ; Shannon diversity index of toxic cyanobacteria in winter, spring and summer gradually decreased, and the values ranged from 2. 774 to 3. 392, from 1. 649 to 2. 619 and from 0. 681 to 1. 996, respectively; and Shannon diversity index was negatively correlated with the ratio of dominant genotype in Sediment samples （p 〈 0.01, r = - 0. 95）. QPCR data suggested that the abundance of mcyA genotypes in sediment samples gradually decreased from winter to summer as a result of cyanobaeteria entering into water column from sediment. The dynamics and composition of toxic cyanobacteria in surface sediment were related to temperature, irradiance, DO content, conductivity and pH.

关 键 词：产毒蓝藻 群落结构 种群丰度 香农多样性指数 定量PCR 

分 类 号：X524[环境科学与工程—环境工程]