艾比湖湿地氨氧化微生物多样性和丰度及其对环境响应的研究

发布时间：2018-06-01 11:25

本文选题：氨氧化细菌 + 氨氧化古菌　；参考：《石河子大学》2017年硕士论文

【摘要】：目的:艾比湖湿地国家自然保护区是国内最具代表性的温带干旱区湿地荒漠生态系统,在调节气候、维持区域生态平衡等方面有着非常重要的作用。氨氧化反应是硝化作用的限速步骤,而参与这一反应的氨氧化微生物是氨氧化细菌(AOB)和氨氧化古菌(AOA)。本研究旨在揭示艾比湖湿地不同植物根际和非根际土壤氨氧化微生物多样性和丰度及其与湿地环境因子的相互关系。方法:本文采集盐节木,芦苇和花花柴根际与非根际的土壤,通过测定土壤理化因子来了解土壤环境的状况。通过构建AOB amoA基因和AOA amoA基因文库来研究不同植物根际氨氧化微生物的多样性。利用实时荧光定量PCR(qPCR)来确定不同植物根际和非根际氨氧化微生物,古菌,细菌的丰度,同时利用冗余分析(redundancy analysis,RDA)揭示氨氧化微生物多样性指数和丰度与土壤环境因子的相关性。结果:土壤理化因子结果显示,盐节木(8.64),芦苇(8.2)、花花柴(8.61)根际土壤的pH均高于其非根际土壤的p H,均为碱性土壤。含水量为:芦苇根际土壤盐节木花花柴;盐节木的根际土壤中电导率最高,芦苇的次之,花花柴的非根际土壤中最低;有机质,全氮,硝态氮,铵态氮的含量在不同植物根际和非根际土壤中均较低,而有效磷和速效钾的含量较高。文库多样性分析显示各植物根际土壤中AOB文库的丰富度、Chao1指数、ACE指数、Shannon-Wiener指数均高于AOA文库的多样性指数。系统发育树结果显示,AOA的序列主要聚为两大簇:Nitrosopumilus和Nitrososphaera cluster。大约92.92%AOA amoA序列都隶属于Nitrosopumilus cluster,是AOA的主要优势种群。AOB的序列主要聚类为Nitrosomonas和Nitrosospira。然而,只有9.76%AOB amoA序列隶属于Nitrosospira genus,90.24%AOB amoA序列隶属于Nitrosomonas genus。Nitrosomonas genus包括四个簇:Nitrosomonas oligotropha cluster,Nitrosomonas-like cluster,Nitrosomonas communis cluster和Nitrosomonas sp.Nm143 cluster。qPCR结果表明,AOA的丰度为(2.09×104-2.94×105)拷贝数/克,其中花花柴根际AOA的丰度最高,是盐节木根际AOA丰度的14.07倍。AOB的丰度为(2.91×105-1.05×106)copies/g,其中芦苇根际AOB的丰度最高。而AOB/AOA的值2.09(花花柴的根际)-29.92(芦苇的非根际)。古菌的丰度范围为(8.78×105-5.15×107)拷贝数/g,而细菌的范围为(4.74×104-4.8×108)拷贝数/g,发现古菌和细菌丰度最低的均在花花柴的非根际土壤中,最高的均在盐节木的根际土壤中。RDA分析表明,电导率,有机质,全氮,铵态氮等与氨氧化微生物的多样性和丰度相关。结论:艾比湖湿地土壤的盐碱程度较高,含水量较低,土壤营养较为贫瘠。根际土壤中AOB的多样性高于AOA。AOA amoA序列隶属于Nitrosopumilus和Nitrososphaera clusters.,AOB amoA隶属于Nitrosospira sp.和Nitrosomonas sp.,其中Nitrosomonas oligotropha cluster和Nitrosomonas communis cluster是AOB的优势种群。AOB的丰度高于AOA的丰度。由此可知AOB在艾比湖湿地氨氧化反应的过程中起着至关重要的作用。电导率,有机质,铵态氮等可能会影响氨氧化微生物的群落结构和丰度。
[Abstract]:Objective: the National Nature Reserve of IBI Lake wetland is the most representative temperate arid region wetland ecosystem, which plays a very important role in regulating the climate and maintaining the regional ecological balance. The ammonia oxidation reaction is the rate limiting step of nitrification, and the ammoxidation bacteria (AOB), which is involved in the reaction, is a ammonia oxidizing bacteria. And ammonia oxidizing palaeobacteria (AOA). This study aims to reveal the interrelationship between the diversity and abundance of ammonia oxidizing microorganisms in the rhizosphere and non rhizosphere soil of different plants in the wetland of ABI lake and their relationship with the environmental factors of the wetland. Methods: This paper collected salt node, reed and flower wood root and non rhizosphere soil, and understand soil ring by measuring soil physical and chemical factors. The AOB amoA gene and the AOA amoA gene library were constructed to study the diversity of the rhizosphere ammonia oxidizing microorganisms in different plants. The real time fluorescence quantitative PCR (qPCR) was used to determine the abundances of the rhizosphere and non rhizosphere ammoxidation microorganisms, the Archaea and the bacteria in different plants, and the ammoxidation was revealed by the redundancy analysis (redundancy analysis, RDA). Results of the correlation between microbial diversity index and abundance and soil environmental factors. Results: the results of soil physical and chemical factors showed that the pH of salting wood (8.64), reed (8.2), flower wood (8.61) rhizosphere soil were all higher than P H in non rhizosphere soil, and all were alkaline soil. The highest conductivity, the second of the reed, the lowest in the non rhizosphere soil of the flower firewood. The content of organic matter, total nitrogen, nitrate nitrogen and ammonium nitrogen in the rhizosphere and non rhizosphere soils of different plants is lower, but the content of available phosphorus and available potassium is higher. The analysis of library diversity shows the richness of the AOB Library in the rhizosphere soil of each plant, the Chao1 index, ACE index, S The hannon-Wiener index is higher than the diversity index of the AOA library. The results of phylogenetic tree show that the sequence of AOA is mainly clustered into two large clusters: Nitrosopumilus and Nitrososphaera cluster. about 92.92%AOA amoA sequences are all subordinate to Nitrosopumilus cluster, which are the main dominant dominant species of.AOB. Ra., however, only the 9.76%AOB amoA sequence is subordinate to the Nitrosospira genus, and the 90.24%AOB amoA sequence is subordinate to the Nitrosomonas genus.Nitrosomonas genus including four clusters. 2.09 x 104-2.94 x 105) copy number / gram, among which, the abundance of AOA in interrhizosphere of flower wood is the highest, and the abundance of AOA abundance of 14.07 times.AOB (2.91 x 105-1.05 * 106) copies/g, which is the highest in reed rhizosphere AOB, while AOB/AOA is 2.09 (rhizosphere of flower firewood). The abundance of palaeo bacteria is (8.78 * 105-5.). 15 * 107) copy number /g, and the range of bacteria (4.74 x 104-4.8 x 108) copy number /g, found that palaeo and bacteria abundances are the lowest in the non rhizosphere soil of flower firewood. The highest.RDA analysis in the rhizosphere soil of salt sawwood shows that the conductivity, organic matter, total nitrogen, ammonium nitrogen and so on are related to the diversity and abundance of ammoxide microorganism. The salinity of the wetland soil in Ebinur Lake is high, the water content is low, and the soil nutrition is relatively poor. The diversity of AOB in the rhizosphere soil is higher than that of the AOA.AOA amoA sequence belonging to Nitrosopumilus and Nitrososphaera clusters.. AOB amoA is subordinate to Nitrosospira sp. and Nitrosomonas sp.. Mmunis cluster is the dominant population of AOB and the abundance of.AOB is higher than that of AOA. Thus, AOB plays a vital role in the process of ammoxidation of the wetland of Ebinur Lake. Electrical conductivity, organic matter, ammonium nitrogen and so on may affect the community structure and abundance of ammoxide microorganism.
【学位授予单位】：石河子大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：S154.3

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