静水压对水库沉积物磷循环转化微生物影响研究

发布时间：2018-11-15 17:55

【摘要】：水库内源磷释放是引发水体富营养化的关键诱因。本文针对黑河金盆水库水体-沉积物多相界面高静水压特性,通过采用传统平板稀释法和先进分子生物学手段(高通量测序技术、荧光定量PCR技术)相结合的方法,基于基本理化性质分析,探讨碱性磷酸酶活性、解磷菌丰度、微生物群落结构以及磷酸激酶表达量在不同静水压条件下的变化。旨在为水污染防治技术提供理论指导。主要结论如下:(1)不同静水压下微生物对多相界面磷转化过程的影响研究结果表明:上覆水中溶解性磷酸盐和总磷含量表现出未灭菌组高于灭菌组,沉积物中总磷含量表现出灭菌组高于未灭菌组。微生物参与磷的迁移转化;高静水压条件下释放进入上覆水的溶解性磷酸盐和总磷含量明显高于常压,常压下沉积物中总磷含量最高,随着静水压的增加,沉积物中总磷含量依次减小。可见,0.1~1.0MPa静水压范围内,高静水压促使沉积物表层中磷向上覆水体发生迁移转化。通过相关性分析再次证实了内源磷释放受到多重环境因子的影响,其中静水压对磷的循环转化具有重要作用。(2)静水压对界面处碱性磷酸酶活性及解磷菌丰度的影响研究结果表明:高静水压促使沉积物中的碱性磷酸酶活性显著增强;与常压条件下沉积物解磷菌数量相比较,0.2MPa、0.5MPa、1.0MPa静水压下沉积物中解磷菌数量均有所增加,尤其是有机解磷菌数量在不同静水压下数量差异明显。通过测定解磷菌解磷能力发现,在0.1~1.0MPa静水压范围内,高静水压下解磷菌的解磷能力明显高于常压;由相关性分析推断得出高静水压下无机解磷菌大量增殖导致其解磷能力增强,而有机解磷菌解磷能力则依靠碱性磷酸酶水解。(3)静水压对界面处微生物群落结构和磷酸激酶影响研究结果表明:在目、科、属、种水平分类上沉积物样品中含有的微生物平均类群数、微生物多样性均随着静水压增加逐渐增加;黑河金盆水库沉积物中的主要细菌类群为变形菌门,其次为拟杆菌门、绿弯菌门、放线菌门等水生生态系统中常见的细菌类群;静水压使沉积物中某些细菌的相对丰度发生规律的变化,例如:门分类水平上,放线菌门、拟杆菌门、疣微菌门表现了规律性,和静水压成响应关系;纲分类水平上,δ-变形菌纲随着静水压增大呈现增加的趋势,ε-变形细菌随着静水压增大呈现减小的趋势,等。磷酸激酶在不同静水压沉积物中均有表达,不同静水压下磷酸激酶在沉积物中的表达量从高到低依次是:0.2MPa、0.5MPa、1.0MPa、常压。
[Abstract]:The release of endogenous phosphorus from reservoir is the key inducement of eutrophication. In view of the high hydrostatic characteristics of the water-sediment multiphase interface in the Jinpan Reservoir of Heihe River, this paper combines the traditional plate dilution method with advanced molecular biology (high-throughput sequencing technique, fluorescent quantitative PCR technique). Based on the analysis of physical and chemical properties, the changes of alkaline phosphatase activity, phosphorus releasing bacteria abundance, microbial community structure and phosphokinase expression under different hydrostatic pressure were studied. The aim is to provide theoretical guidance for water pollution prevention and control technology. The main conclusions are as follows: (1) the effects of microbes on the process of phosphorus conversion at heterogeneous interface under different hydrostatic pressures showed that the contents of dissolved phosphate and total phosphorus in the overlying water were higher than those in the non-sterilized group. The total phosphorus content in sediment was higher in sterilizing group than in non-sterilized group. Microbes participate in the transport and transformation of phosphorus; The contents of dissolved phosphate and total phosphorus released into overlying water under high hydrostatic pressure were significantly higher than those in atmospheric pressure, and the total phosphorus content in sediment was the highest at normal pressure, and decreased in turn with the increase of hydrostatic pressure. In the range of 0.1~1.0MPa hydrostatic pressure, high hydrostatic pressure promoted the transport and transformation of phosphorus to the overlying water in the surface layer of sediment. The correlation analysis confirmed that the release of endogenous phosphorus was affected by multiple environmental factors. Among them, hydrostatic pressure plays an important role in phosphorus cycling. (2) the effect of hydrostatic pressure on alkaline phosphatase activity at the interface and the abundance of phosphorus releasing bacteria showed that high hydrostatic pressure significantly enhanced alkaline phosphatase activity in sediment; Compared with the amount of phosphorus releasing bacteria in sediment under atmospheric pressure, the amount of phosphorus releasing bacteria in sediment increased under 0.2MPA ~ (0.5) MPA hydrostatic pressure, especially in organic phosphorus bacteria under different hydrostatic pressure. It was found that in the range of hydrostatic pressure of 0.1~1.0MPa, the ability of phosphorus releasing bacteria in high hydrostatic pressure was significantly higher than that in normal pressure. It was inferred from the correlation analysis that the proliferation of inorganic phosphorus releasing bacteria under high hydrostatic pressure resulted in the enhancement of phosphorus releasing ability. However, the ability of organophosphorus to dissolve phosphorus was hydrolyzed by alkaline phosphatase. (3) the effect of hydrostatic pressure on microbial community structure and phosphokinase at the interface showed that: in order, family, genus, The average number of microbes contained in sediment samples and the microbial diversity increased with the increase of hydrostatic pressure. The main bacterial groups in the sediments of the Jinpan Reservoir of Heihe River were Proteus, followed by Bacteroides, Chlorophyta, Actinomycetes, and other common bacteria groups in aquatic ecosystems. Hydrostatic pressure changes the relative abundance of some bacteria in sediment. For example, at the phylum classification level, actinomycetes, Bacteroides and verruca microphylum show regularity, and hydrostatic pressure is responsive; At the taxonomic level, 未-Proteus increased with the increase of hydrostatic pressure, and 蔚-Proteus decreased with the increase of hydrostatic pressure, etc. Phosphokinase was expressed in sediment with different hydrostatic pressure. The order of phosphokinase expression in sediment was 0.2MPA, 0.5MPA, 1.0MPa, and normal pressure, respectively.
【学位授予单位】：西安科技大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：X524

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