Microbial Transformations at Deep-Sea Hydrothermal Vents

深海热液喷口的微生物种群将地热能的转移与有机碳的生产联系起来，即化学合成。游离菌是滤食和放牧喷口动物的颗粒有机食物来源，是这部分喷口群落食物链的化学合成基础。在RIDGE计划继续进行期间，该项目将重点研究热液喷口中的细菌。Jannasch博士将回答这个问题——在热液喷口的产量方面，哪种化学合成细菌在数量上是最重要的？为了回答这个问题，新开发的技术将用于评估各种排气环境下的好氧和厌氧化学合成细菌。生长和化学合成的速率将通过各种原位和实验室实验来测量。假设这些天然微生物种群对环境条件的反应非常灵敏，因此它们代表了喷口系统的时间地球物理-地球化学变化。在大西洋中脊喷口的工作将处理覆盖多金属硫化物矿床的微生物种群的化学合成活动的原位速率测量的新方法。此外，还计划在Guaymas盆地Beggiatoa地垫开展工作。这些研究将涉及使用阿尔文号和JASON/ medea号两艘潜水器

Microbial populations at deep-sea hydrothermal vents link the transfer of geothermal energy to the production of organic carbon, known as chemosynthesis. As the particulate organic food source for the filter-feeding and grazing vents animals, free-living bacteria function as the chemosynthetic base of the food chain for this part of the vent communities. During the continuation of the RIDGE Initiative, this project will focus on those bacteria from hydrothermal vents. Dr. Jannasch will address the question - which chemosynthetic bacteria are quantitatively the most important in terms of productivity at hydrothermal vents? To answer this question, newly-developed techniques will be used to assess aerobic and anaerobic chemosynthetic bacteria at a large variety of vent environments. Rates of growth and chemosynthesis will be measured by a variety of in situ and laboratory experiments. It's assumed that these natural microbial populations are highly responsive to environmental conditions and, therefore, representative of temporal geophysical-geochemical changes of vent systems. Work at the Mid- Atlantic Ridge vent sites will deal with new approaches for in situ rate measurements of chemosynthetic activity by microbial populations covering the polymetal sulfide deposits. In addition, work is also planned for the Guaymas Basin Beggiatoa mats. These studies will involve the use of two submersibles, the ALVIN and JASON/MEDEA.//