【作者】 陈威；

【导师】 王振宇； 李培睿；

【作者基本信息】 河南师范大学 ， 微生物学， 2010， 硕士

【摘要】 富营养化已经成为水体环境中的普遍问题,由富营养化带来的一系列问题也日益引起人们的关注。与其他修复方法相比生物方法具有无副作用并且容易操作等优点,因此成为水体富营养化修复研究的热点。而微生物作为生态系统中物质转化的主体,在水环境有机物的降解与转化过程中发挥着重要作用。因此,开展对淡水生境中水华暴发不同阶段时细菌群落结构、功能和多样性的变化研究,对于富营养化的治理以及丰富湖沼学理论具有重要的意义。本研究以洋河水库和密云水库的表层水作为实验材料,分别在两地连续采集水样。使用显微镜镜检技术对水样中藻的总量进行统计,并结合水质数据以衡量水华的不同状态。采用现代分子生物学技术分别对洋河水库和密云水库不同水华状态下细菌群落结构的变化进行了研究,并对不同生境条件下细菌群落结构的变化进行了比较分析。采用显微镜计数和DAPI染色相结合的方法分别对两地不同水样进行了总细菌的计数。结果表明,在水华前期藻类的大量增殖过程中,总细菌的含量呈降低的趋势,而在水华高峰期至逐渐消减的过程中总细菌的含量则相对稳定。洋河水库水华的程度要甚于密云水库。分别采用PCR-DGGE和16S rDNA克隆技术对两水库不同水华状态下细菌的群落结构进行分析。PCR-DGGE分析结果表明:水华暴发前和水华基本消失时的细菌群落结构与水华暴发高峰期差别很大;放线菌在洋河水库不同水华阶段稳定存在,而在密云水库不同的水华阶段其存在量差别明显;α-proteobacteria在两水库的不同水华阶段均有存在,在洋河水库水华的末期α-proteobacteria的存在量要高于其它阶段,而在密云水库α-proteobacteria存在量较高时期出现在水华的早期阶段。16S rDNA克隆文库分析结果表明:在两水库不同水华阶段放线菌门类群的分布比例与PCR-DGGE分析结果一致;α-proteobacteria、β-proteobacteria、γ-proteobacteria、Verrucomicrobia、Fibrobacteres、Planctomycetes、Chloroflexi类群在两水库中伴随藻类的增减过程具有不同的演替规律;Bacteroidetes类群的个体无论是种类还是数量上,在藻的暴发与休眠时期均存在明显的差异,藻类暴发期的种类和数量均低于休眠期;在洋河水库水华发生过程中,细菌的均度变化较大,而密云水库在水华发生的过程中,细菌的均度变化不大。更多还原

【Abstract】 Eutrophication in the water environment, which would result in a series of problems, had become an environmental and scientific project. Biological treatment method has obvious advantage in contrast to physico-chemical methods because of no side effects and easy operation. And also microorganisms are responsible for the degradation and transformation of organic matter in water environment. Therefore, the researches about the bacterial community structure, function and diversity during the water bloom have great significances for the eutrophication remediation and enriching the limnology theory.This study choosed Yanghe Reservoir and Miyun reservoir as the experimental spots. Five surface water samples were collected continuously in the two Reservoirs, respectively. Different states of water bloom are measured by water quality and total amount of algae in water samples which were calculated by microscopy technique. The bacterial community structure of all the samples was studied by molecular biology techniques. And also the microbial community structure in the two reservoirs was compared.The total number of bacteria was examined respectively in different water samples by using microscopy technique and DAPI staining. The results showed that the total number of bacteria decreased in the early stage of water bloom, while there were no changes in the later period of water bloom. The eutrophication degree in Yanghe reservoir was higher than that of Miyun Reservoir.The bacterial community structure during different water bloom stages was studied by PCR-DGGE and 16S rDNA cloning technique. The results by PCR-DGGE indicated that the occurrence of water bloom had a significant impact on the Bacterial community structure. The content of Actinomycetes in Yanghe reservoir was stable during different stages of bloom, while in Miyun reservoir it was fluctuated between different stages of water bloom. Theα-proteobacteria existed in each stage of water bloom in the two reservoirs. Its abundance is higher in the later stage of water bloom in Yanghe reservoir. But in Miyun reservoir it was higher in the early stage. Furthermore, the results by 16S rDNA clone confirmed that the proportion of actinomycetes in different stages of water bloom in the two reservoirs was consistent with the result by PCR-DGGE. Theα-proteobacteria,β-proteobacteria,γ-proteobacteria, Verrucomicrobia, Fibrobacteres, Planctomycetes and Chloroflexi have different rules of succession in different reservoirs in the process of water bloom. But both species and quantity of Bacteroidetes were less in the outbreak period of algae than that in the rest period which showed different rule as other populations. The evenness of bacteria changed greatly in Yanghe reservoir, while little change was happened in Miyun Reservoir during the water bloom cycle.更多还原