Collaborative Research: In Situ Measurement of Rates of Chemoautotrophic Carbon Production at Deep-Sea Hydrothermal Vents

国际海洋局要求提供资金，以开发喷口时间序列潜水孵化装置，这是一个供海洋学界常规应用的机器人微型实验室，用于测量在原地压力和温度下热液喷口的相关代谢过程的速率。关于在深海热液喷口进行二氧化碳固定的微生物的原位新陈代谢知识非常有限。尤其缺乏测量原地自养固碳速率的研究，这是限制这些生态系统生产的最终需要的测量。尽管最近的数据表明，硝酸盐还原为N_2(反硝化)或NH_4+(硝酸盐异化还原为氨氮，DNRA)可能是很大一部分化学自养产物的原因，但在热液喷口中，NO_3~-还原速率从未被现场测量过。更广泛的影响：根据这项拟议工作开发的喷口-TSSID将提供给研究界，供其他深海喷口使用。这笔赠款将资助两名研究生，一名在世界卫生组织，另一名在布朗大学。PI还让本科生参与他们的研究项目，并计划继续这样做。西弗特博士目前参与了世界卫生组织科学和技术教育伙伴关系，里奇博士一直是布朗环境研究员计划的积极参与者。

The PI's request funding to develop a Vent-Time Series Submersible Incubation Device (Vent-TSSID), a robotic micro-laboratory for routine application by the oceanographic community for measuring rates of relevant metabolic processes at hydrothermal vents at both in situ pressures and temperatures. Knowledge of the in situ metabolism of microorganisms carrying out CO2-fixation at deep-sea hydrothermal vents is very limited. Particularly lacking are studies measuring rates of autotrophic carbon fixation in situ, which is a measurement ultimately needed to constrain production in these ecosystems. Although recent data suggests that nitrate reduction either to N2 (denitrification) or to NH4 + (dissimilatory reduction of nitrate to ammonium, DNRA) might be responsible for a significant fraction of chemoautotrophic production, NO3 --reduction rates have never been measured in situ at hydrothermal vents. Broader Impacts: The Vent-TSSID developed from this proposed work will be made available to the research community for use at other deep sea vents. This grant would fund 2 graduate students, one at WHOI and the other at Brown University. The PIs also have involved undergraduates in their research programs and plan to continue to do so. Dr. Sievert currently participates in the WHOI Science and Technology Education Partnership, and Dr. Rich has been an active participant in the Brown Environmental Fellows program.