潮间带古菌介导的甲烷厌氧氧化过程研究

发布时间：2018-01-24 02:31

本文关键词： ANME-2d古菌 ANMEs古菌硝酸盐型甲烷厌氧氧化(Nr-DAMO) 硫酸盐型甲烷厌氧氧化(SAMO) 潮间带环境因子　出处：《浙江大学》2017年硕士论文　论文类型：学位论文

【摘要】：潮间带生态系统富含有机质,在厌氧条件下分解产生大量的甲烷和含氮无机物,潮间带在海洋生态系统碳氮循环中扮演重要角色。在海洋生态系统中甲烷主要通过硫酸盐型甲烷厌氧氧化(SAMO)过程去除,SAMO过程由甲烷厌氧氧化古菌(ANMEs)与硫酸盐还原细菌(SRB)共同完成,而其他甲烷厌氧氧化过程一直被忽略。研究发现,除归属于NC10门的细菌M.oxyfera和M.sinica能通过亚硝酸盐型厌氧甲烷氧化(N-DAMO)反应去除潮间带产生的甲烷,归属于ANME-2d的古菌M.nitrorucens也可以通过逆向产甲烷途径耦合硝酸盐的还原去除潮间带中的甲烷和硝酸盐(Nr-DAMO)。ANMEs古菌及ANME-2d古菌在自然生境中分布广泛,而关于两类古菌在潮间带生态系统中分布及活性的研究较少。本文就ANMEs古菌及ANME-2d古菌在潮间带生态系统中的数量、多样性、群落结构、活性、相关环境影响因子及其在甲烷氧化中的相对贡献做了详细研究,主要研究结果如下:1.探索了舟山潮间带生态系统中ANME-2d古菌及NC10门细菌的数量、多样性、群落组成、活性及主要影响因子。1)稳定同位素示踪发现,在不同潮间带采样点潜在Nr-DAMO活性为0-1.57 nmol 13CO2 g'1(dry sediment)day-1。Nr-DAMO过程在甲烷厌氧氧化过程中对甲烷去除的贡献率为22.3%-60.6%,表明Nr-DAMO过程在潮间带生态系统中是之前被忽略的重要甲烷汇。2)系统发育分析表明,舟山潮间带沉积物中的ANME-2d古菌具有较高的多样性。通过qPCR,检测到不同潮间带采样点ANME-2d古菌的16S rRNA基因拷贝数分别为 4.34×104-1.18×105 copies g-1(dry sediment)。3)皮尔逊相关性分析及RDA分析表明,硝氮与硫酸盐是该区域影响ANME-2d古菌多样性及Nr-DAMO活性的主要环境因子。2.探索了舟山潮间带生态系统中ANMEs古菌的数量、多样性、群落组成、活性及主要影响因子。1)稳定同位素示踪发现,由ANMEs古菌介导的SAMO过程的潜在甲烷厌氧氧化活性为0-0.77 nmol 13CO2 g-1(dry sediment)day-1,占总甲烷厌氧氧化过程的比例为0.345,表明SAMO过程是潮间带生态系统重要的不可忽视的甲烷汇。2)通过定量PCR和Illumina高通量测序发现,在舟山潮间带沉积物中含有大量的ANMEs古菌,其16S rRNA基因拷贝数为9.10× 105-1.13×107 copies(g dry sediment)-1。潮间带生境中ANMEs古菌多样性较高,这是由潮间带独特的环境条件决定的。3)皮尔逊相关性分析及RDA分析表明,温度、ORP、硫酸盐及TOM是影响潜在SAMO活性、ANMEs古菌数量和群落组成的主要环境因子。3.探索了模拟生境中ANME-2d古菌及ANMEs古菌的数量、多样性、群落组成、活性及主要影响因子。1)稳定同位素示踪发现,模拟生境中潜在Nrr-DAMO活性为0.16-1.4913CO2 g-1(dry sediment)day-1;潜在 SAMO 活性为 0.00-2.78 13CO2 g-1(dry sediment)day-1,占总甲烷厌氧氧化过程的比例分别为21.28%-56.15%与19.90%-53.12%,表明Nr-DAMO过程及SAMO过程在模拟土柱生态系统中对甲烷的去除同样具有重要作用。2)定量PCR和Illumina高通量测序发现,在模拟生境样品中含有大量的甲烷厌氧氧化古菌。其中ANMEs古菌及ANME-2d古菌的16S rRNA基因拷贝数分别为 1.11 ×106-2.13×107 copies(g dry sediment)-1及 1.07×104-2.60×105 copies(gdrysediment)1。模拟生境中甲烷厌氧氧化古菌多样性较高,氧气浓度是影响其多样性及数量的重要因素。3)皮尔逊相关性分析及RDA分析表明,模拟实验验证了在原位潮间带生境中沉积物溶解氧浓度、硫酸盐、硝氮及TOM是影响甲烷厌氧氧化古菌数量、活性及群落结构的主要影响因素。
[Abstract]:The ecosystem is rich in organic matter in intertidal zone, produce large amounts of methane and inorganic nitrogen compounds under anaerobic conditions, decomposition, play an important role in the carbon and nitrogen cycling in the marine ecosystem, intertidal zone. Methane in the marine ecosystem mainly through sulfate type anaerobic oxidation of methane (SAMO) removal process, SAMO process by anaerobic methane oxidizing archaea (ANMEs) and sulfate reducing bacteria (SRB) together, and other anaerobic methane oxidation process has been neglected. The study found that, in addition to belong to the NC10 gate M.oxyfera and M.sinica by nitrite bacteria anaerobic methane oxidation (N-DAMO) reaction to remove methane from the intertidal zone, archaea belong to M.nitrorucens ANME-2d can also through the reduction of methane and nitrate in the intertidal reverse pathway of methane production coupled nitrate (Nr-DAMO).ANMEs and ANME-2d ancient Archaea were widely distributed in the natural habitat, and Study on the distribution and activity of ecological system of two kinds of Archaea in the intertidal zone is less. The ANMEs and ANME-2d Archaea Archaea in the intertidal zone number, ecosystem diversity, community structure, activity, related environmental impact factors and their relative contributions in methane oxidation are studied in detail, the main the results are as follows: 1. to explore the number of ANME-2d and NC10 bacteria Archaea door ecosystem in the intertidal zone of Zhoushan consists of diversity, community activities, and the main influence factor.1) stable isotope tracer, with sampling point potential Nr-DAMO activity was 0-1.57 nmol 13CO2 g'1 in different intertidal (dry sediment) day-1.Nr-DAMO removal process the methane in anaerobic oxidation of methane in the process of the contribution rate of 22.3%-60.6%, Nr-DAMO in the intertidal ecosystem that is important before being ignored methane sink.2) phylogenetic analysis indicated that the intertidal zone of Zhoushan The sediment ANME-2d in archaea has higher diversity. Through the qPCR, detected the copies of 16S rRNA gene with different sampling point ANME-2d Archaea intertidal were 4.34 * 104-1.18 * 105 copies g-1 (dry sediment).3) Pearson correlation analysis and RDA analysis showed that nitrate and sulfate in the region is the main influence environmental factors.2. ANME-2d archaeal diversity and Nr-DAMO activity and exploration of the number of ANMEs ecosystem Archaea in the intertidal zone of Zhoushan's diversity, community composition, activity and the main influence factor.1) stable isotope tracer showed that potential anaerobic methane oxidation activity of SAMO by ANMEs mediated the Archaea 0-0.77 nmol 13CO2 g-1 (dry sediment day-1), accounting for the anaerobic oxidation process of total methane ratio of 0.345, showed that the SAMO process is the intertidal ecosystem very important sink for methane.2) by quantitative PCR and Illumina high throughput test The order found in Zhoushan intertidal sediments contain a large number of ANMEs archaea, 16S copy number of the rRNA gene is 9.10 * 105-1.13 * 107 copies (g dry sediment) ANMEs habitats in the archaeal diversity of -1. high intertidal zone, which is composed of the intertidal zone of the unique environmental conditions decide.3) Pearson correlation analysis and RDA analysis showed that the temperature, ORP, and TOM is the impact of potential sulfate SAMO activity, ANMEs Archaea quantity and composition of the main environmental factors of.3. in simulated habitat quantity, ANME-2d and ANMEs of the archaeal diversity of archaea, community activity and the main influencing factors of.1 stable isotope tracer found) the activity of Nrr-DAMO, the potential for 0.16-1.4913CO2 g-1 in simulated habitat (dry sediment) day-1 SAMO 0.00-2.78 13CO2; the potential activity of g-1 (dry sediment day-1), the proportion of the total process of anaerobic oxidation of methane were 21.28% -56.15% and 19.90%-53.12% table The Nr-DAMO process and SAMO process in soil column simulated ecosystem on the removal of methane also plays an important role in.2 and Illumina PCR) quantitative high-throughput sequencing found that Archaea contain anaerobic oxidation of methane in a large number of simulated habitat samples. Which copies of the 16S rRNA gene ANMEs ANME-2d and archaeal Archaea were 1.11 * 106-2.13 * 107 copies (g dry sediment) -1 and 1.07 * 104-2.60 * 105 copies (gdrysediment) 1. in simulated habitat anaerobic methane oxidizing archaea diversity is higher, the oxygen concentration is an important factor affecting the diversity and number of.3) Pearson correlation analysis and RDA analysis showed that the simulations with the dissolved oxygen concentration in sediments in situ intertidal habitats, sulfate, nitrate and TOM affect the number of anaerobic methane oxidizing archaea, main factors affecting the activity and community structure.

【学位授予单位】：浙江大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：X172

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