Patterns of Microbial Community Structure Within and Between Hadal Environments

深渊环境内部和之间的微生物群落结构模式

• 批准号: 1536776
• 负责人: Douglas Bartlett
• 金额: $ 14.11万
• 依托单位: University of California-San Diego Scripps Inst of Oceanography
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-09-01 至 2019-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1536776&HistoricalAwards=false
• 关键词: Patterns; Microbial; Community; Structure; Within

The deepest portion of the ocean is present in ocean trenches, whose steep walls descend from approximately 4 miles down to depths that in some cases are close to 7 miles below the seawater surface. At these locations Earth's crust is recycled. Perhaps not surprisingly given their remoteness, deep ocean trenches are the least understood habitats in the ocean. The researchers participating in this project are working to characterize the microbes present in two of the deepest trenches present on Earth, both in the Pacific Ocean, the Kermadec Trench located north of New Zealand, and the Mariana Trench, located east and south of the island of Guam. Most of the Mariana Trench is located within the United States Mariana Trench Marine National Monument. Relatively little is known about the diversity and adaptations of the microorganisms in deep ocean trenches. An unknown fraction of the microbes present have descended from shallow waters above and are unlikely to participate in any nutrient cycles in the deep sea. Others are adapted to near freezing temperatures and up to pressures greater than 10e7 kilograms per square meter (16,000 pounds per square inch). These latter microbes perform important roles recycling organic matter. But who are they? This project is contributing to the training of diverse undergraduate and graduate students participating in research, additional undergraduate students learning about microbes inhabiting extreme environments in a web-based class, and additional graduate students and postdoctoral scientists participating in an advanced training course being offered in Antarctica.Experiments being performed include direct counts of prokaryotes and viruses in seawater and sediments, analyses of the abundance and phylogenetic breadth of culturable heterotrophic bacteria at a range of pressures, measurements of bacterial community species diversity and richness both within and across seawater and sediment samples, as well as within and across the two trench systems, measurements of microbial activity as a function of pressure and the identification of high pressure-active cells. The data generated from these analyses are being integrated into the results of additional chemical, geological and biological measurements performed by others as a part of the National Science Foundation funded Hadal Ecosystems Studies Project. Two of the working hypotheses are that prokaryote numbers and diversity are generally positively correlated with surface productivity and proximity to the trench axis and that bacterial taxa exist which are endemic to specific trenches, present in multiple trenches and more widely distributed in deep-sea environments.

海洋最深的部分存在于海沟中，海沟的陡壁从大约 4 英里处下降到某些情况下接近海水表面以下 7 英里的深度。 在这些地方，地壳被回收。 考虑到地处偏远，深海海沟是海洋中最不为人所知的栖息地，这也许并不奇怪。 参与该项目的研究人员正在努力表征地球上两个最深海沟中存在的微生物，这两个海沟都位于太平洋，位于新西兰北部的克马德克海沟和位于该岛东部和南部的马里亚纳海沟关岛。 马里亚纳海沟的大部分位于美国马里亚纳海沟海洋国家保护区内。 人们对深海海沟微生物的多样性和适应性知之甚少。 存在的微生物中有一小部分是从上面的浅水区下降的，不太可能参与深海的任何营养循环。 其他的则适应接近冰点的温度和高于每平方米 10e7 公斤（每平方英寸 16,000 磅）的压力。 后面这些微生物在回收有机物方面发挥着重要作用。 但他们是谁？ 该项目有助于培训参与研究的多元化本科生和研究生，更多本科生在网络课程中了解栖息在极端环境中的微生物，以及更多研究生和博士后科学家参加在南极洲提供的高级培训课程正在进行的实验包括对海水和沉积物中的原核生物和病毒进行直接计数、在一定压力下分析可培养异养细菌的丰度和系统发育广度、测量细菌群落物种多样性和海水和沉积物样品内部和之间以及两个沟渠系统内部和之间的丰富度、作为压力函数的微生物活性测量以及高压活性细胞的识别。这些分析生成的数据正在被整合到其他人进行的额外化学、地质和生物测量的结果中，作为国家科学基金会资助的深渊生态系统研究项目的一部分。 其中两个工作假设是，原核生物的数量和多样性通常与表面生产力和与海沟轴的接近程度呈正相关，并且存在特定海沟特有的细菌类群，存在于多个海沟中，并且更广泛地分布在深海环境中。