三峡库区消落带湿地反硝化型厌氧甲烷氧化菌的存在与分布特征

发布时间：2018-01-25 10:57

本文关键词： 反硝化型厌氧甲烷氧化菌群落结构丰度三峡库区消落带湿地　出处：《武汉纺织大学》2015年硕士论文　论文类型：学位论文

【摘要】：由“Candidatus Methylomirabilis oxyfera”(M.oxyfera)介导的反硝化型厌氧甲烷氧化(nitrate/nitrite dependent anaerobic methane oxidation,n-damo)过程发现于2006年,它的发现对完善全球碳氮循环理论有着重要意义。目前对n-damo的研究主要集中在不同类型生境和污水处理反应器中,该过程在三峡库区消落带这一高扰动生境中是否存在仍未知。本文利用分子生物学手段与理化性质分析对三峡库区消落带中n-damo的存在、分布与多样性进行了研究,结果如下:(1)本研究通过定量PCR方法成功定量出三峡库区消落带湿地中n-damo菌的丰度,并采用基因克隆文库技术在库区消落带中成功检测出n-damo菌特异性序列,证实了n-damo菌在该大幅水位波动背景下的消落带湿地中的存在。(2)三峡库区消落带湿地中存在多个与M.oxyfera亲缘关系较近的分支。在所研究的无人为干扰的自然消落带湿地和受人为影响的消落带湿地中,仅水下沉积物中检测到属Group a的n-damo菌,同时所选两个消落带湿地中的优势n-damo菌均属Group b。(3)通过q PCR技术在两个库区消落带湿地不同高程样品中菌检测到了一定数量的n-damo菌,丰度范围为102~105 copies g-1干土。在库区消落带湿地沉积物中n-damo菌丰度大多明显高于土壤样品中n-damo菌丰度(2013年10月自然消落带中沉积物、土壤样品n-damo菌丰度变化范围分别为1.05×103~1.45×103copies g-1干土和4.79×102~5.16×102 copies g-1干土,2014年4月则为4.21×104~5.32×104 copies g-1干土和3.17×103~7.69×103 copies g-1干土,2013年10月受人为干扰的消落带湿地分别为2.01×103~3.54×103 copies g-1干土和8.98×102~1.09×102 copies g-1干土),表明水下沉积物是消落带中n-damo菌的主要分布区域。相关性分析结果显示,自然消落带湿地中n-damo菌丰度与环境因子无明显相关性,受人为影响的消落带湿地中有机质含量与n-damo菌群丰度相关性显著。
[Abstract]:Denitrifying anaerobic methane Oxidation mediated by "Candidatus Methylomirabilis oxyfera" M. oxyfera. Nitrate/nitrite dependent anaerobic methane oxidation. The n-damo) process was discovered in 2006. The discovery of n-damo is of great significance to improve the global carbon and nitrogen cycle theory. At present, the research on n-damo is mainly focused on different types of habitats and sewage treatment reactors. It is still unknown whether this process exists in the highly disturbed habitat of the three Gorges reservoir area. In this paper, the existence of n-damo in the collapse zone of the three Gorges reservoir area is analyzed by molecular biological methods and physicochemical properties. The distribution and diversity were studied. The results were as follows: 1) in this study, the abundance of n-damo bacteria in the wetland of the three Gorges Reservoir area was determined by quantitative PCR method. The specific sequence of n-damo bacteria was successfully detected by gene cloning library technique in the banding zone of reservoir area. It is confirmed that n-damo bacteria exist in the wetland of the subsidence zone under the background of large water level fluctuation. There are many branches close to M. oxyfera in the wetland of the three Gorges Reservoir area. Only n-damo bacteria belonging to Group a were detected in underwater sediments. The dominant n-damo bacteria in the wetland of the two decaying zones were all Group B. A certain number of n-damo bacteria were detected by Q PCR technique in different elevation samples of wetland in two reservoir areas. The abundance of n-damo bacteria in wetland sediments of reservoir area is significantly higher than that in soil samples (P < 0.05). The abundance range of n-damo bacteria in dry soil is 102 ~ 10 ~ 5 copies g ~ (-1). In October 2013, sediments in the natural subsidence zone. The variation ranges of n-damo abundance in soil samples were 1.05 脳 10 ~ (3) C ~ (-1) and 4.79 脳 10 ~ (2) ~ (2) C _ (5.16) 脳 10 ~ (2), respectively. Copies g-1 dry soil. In April 2014, it was 4.21 脳 104 copies g-1 dry soil and 3.17 脳 10 3 copies g -1 dry soil and 3.17 脳 10 3 脳 10 4 copies g -1 dry soil and 3.17 脳 10 3 脳 10 3 copies g -1 dry soil. G-1 dry soil. In October 2013, the number of artificial disturbance wetlands was 2.01 脳 10 ~ 3 ~ 3.54 脳 10 ~ (3) copies, respectively. G-1 dry soil and 8.98 脳 102 copies g-1 dry soil. . The results of correlation analysis showed that there was no significant correlation between the abundance of n-damo bacteria and environmental factors. There was a significant correlation between the content of organic matter and the abundance of n-damo flora.
【学位授予单位】：武汉纺织大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：X172

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