内蒙古荒漠生物土壤结皮及下层土壤微生物多样性和群落结构研究

发布时间：2018-03-28 12:17

本文选题：内蒙古荒漠　切入点：BSCs　出处：《内蒙古农业大学》2015年硕士论文

【摘要】：荒漠化是全球最重要的生态和环境问题之一,荒漠化对我国的危害和影响也极其严重。而内蒙古又多荒漠,常被指为“沙尘暴”的祸源,是我国防治荒漠化的重点地区。生物土壤结皮(biological soil crusts, BSCs)能够遏制土壤荒漠化,在荒漠生态系统稳定、修复和重建中具有重要意义。微生物是BSCs的重要组成成分,在其发育形成过程中扮演重要角色。但是,内蒙古荒漠BSCs及其相邻下层土壤微生物群落组成尚不清楚,进行相关研究可为明确微生物在BSCs的作用和功能提供佐证,并为相关微生物资源的开发和利用奠定基础,具有重要的理论意义和实践价值。基于Miseq高通量测序,本研究对比分析库布齐和毛乌素荒漠在不同季节、不同类型BSCs及其紧邻下层土壤中微生物群落结构,并结合理化性质测定进行微生物群落和环境因子关系的分析。研究结果和结论如下：(1)土壤理化性质：BSCs的pH值、含水量小于其相应下层土壤的,而有机质、速效氮、叶绿素含量却相反；同一地点同一类型样品的相比较,pH为5月份高于9月份；BSCs速效氮含量为5月份低于9月份,而速效磷和有机质含量变化相反；下层土壤速效氮、速效磷含量为5月份低于9月份,有机质含量则相反。(2)微生物多样性时空差异明显：9月份的高于5月份的；BSCs中细菌的多样性一般高于下层土壤的,而多数BSCs真菌多样性低于下层土壤：毛乌素微生物多样性高于库布齐的。(3)群落结构：5月份12个样品细菌OTU有585-1130个,优势群落有Proteobacteria (9.46%-39.99%)、Firmicutes (0.000035%-63.48%)、Acidobacteria (0.13%-40.89%)、ctinobacteria (4.71%-30.89%)、Bacteroidetes (1.92%-27.68%)、 Chloroflexi (0.19%-7.05%)、Cyanobacteria (0.034%-45.54%)、Gemmatimonadetes (0.013%-11.53%)。BSCs中以Proteobacteria、Cyanobacteria及Bacteroidetes为优势菌群,而下层土壤以Proteobacteria、 Acidobacteria和Actinobacteria为优势菌群；9月份11个样品,细菌OTU有4348-7439个,优势群落有Proteobacteria (26.91%-48.86%)、Bacteroidetes (2.52%-13.39%)、 Actinobacteria (7.33%-44.61%)、 Fusobacteria (0.00%-5.61%)、Acidobacteria (7.62%-23.50%)、Gemmatimonadetes (1.15%-6.77%)、Firmicutes (0.23%-9.35%)。BSCs中以Proteobacteria, Actinobacteria, Bacteroidetes及Cyanobacteria而下层土壤以Proteobacteria、Actinobacteria, Bacteroidetes为优势菌群。9月份真菌OTU有90-417个,主要划分为5个门,分别有Zygomycota(接合菌门)(0.00%-9.770%)、Basidiomycota(担子菌门)(0.00%-30.69%)、Glomeromycota(球囊菌门)(0.00%-0.12%)、Chytridiomycota(壶菌门)(0.00%-1.6%)、Ascomycota(子囊菌门)(7.28%-50.50%)及大部分未分类类群。(4)微生物群落与环境因子关系：土壤含水量、有机质、叶绿素和pH对微生物群落组成影响较大,速效氮和速效磷对微生物群落分布影响较小。
[Abstract]:Desertification is one of the most important ecological and environmental problems in the world, and the damage and impact of desertification on China is extremely serious. Biological soil crusts (BSCs) can contain soil desertification and play an important role in the stabilization, restoration and reconstruction of desert ecosystems. Microbes are important components of BSCs. However, the composition of microbial communities in desert BSCs and its adjacent subsoil in Inner Mongolia is not clear. The relevant studies can provide evidence for determining the role and function of microbes in BSCs. It is of great theoretical and practical value for the exploitation and utilization of related microbial resources. Based on the high throughput sequencing of Miseq, this study compared and analyzed the desert of Kubuqi and Maowusu in different seasons. The relationship between microbial community and environmental factors in different types of BSCs and its adjacent subsoil was analyzed with physicochemical properties. The results and conclusions are as follows: (1) pH value of soil physical and chemical properties of BSCs. The contents of organic matter, available nitrogen and chlorophyll in the soil were lower than those in the corresponding subsoil, and the pH value in May was higher than that in September, and the content of available nitrogen in May was lower than that in September. The contents of available phosphorus and organic matter were opposite, and the available nitrogen and phosphorus contents in the lower soil were lower in May than in September. The difference of microbial diversity in September was higher than that in May, and the diversity of bacteria in BSCs was generally higher than that in lower soil. The majority of BSCs fungi diversity is lower than that of the lower soil: the structure of 12 samples of OTU in May is 585-1130, and the dominant community is Proteobacteria 9.46-39.9999. The dominant community is Proteobacteria 9.46-39.9999. The dominant community is Proteobacteria 9.46-39.9999. The dominant community is Proteobacteria 9.46-39.999. Firmicutes 0.000035-63.48. I am in the lower soil. I am in the position of 4.71-30.89Bacteroidetes 1.92-27.68m, Chloroflexi 0.19-7.05Cyanobacteria 0.034-45.5454. Gemmatimonianobacteria and Bacteroidetes are the dominant groups in BSCs. In the lower soil, there are 11 samples of Proteobacteria, Acidobacteria and Actinobacteria as dominant flora in September, and 4348-7439 in bacterial OTU. The dominant communities are Proteobacteria 26.91-48.86tes 2.52- 13.3939, Actinobacteria 7.33-44.61, Fusobacteria 0.00-5.61a, Fusobacteria 0.00-5.61acidobacteria 7.62-23.50. Gemmatimonadetes 1.15-6.77Micutes 0.23-9.35.Bin order of Proteteria, Actinobacteria, Bacteroidetes and Cyanobacteria, there are OTU OTU Bacteroidetes in the lower soil. There are five main divisions, Zygomycota (0.00-9.7707) and Basidiomycotaa (Basidiomycotaa). The relationship between microbial community and environmental factors: soil water content, organic matter, soil water content, organic matter, Chlorophyll and pH had great influence on the composition of microbial community, and available nitrogen and phosphorus had little effect on the distribution of microbial community.
【学位授予单位】：内蒙古农业大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：S154

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