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

PI申请资金用于开发一个通气时间系列潜水孵化装置（Vent-TSSID），这是一个机器人微型实验室，用于海洋学社区的常规应用，用于测量热液喷口在原位压力和温度下相关代谢过程的速率。对在深海热液喷口进行二氧化碳固定的微生物的原位代谢的了解非常有限。尤其缺乏测量原地自养碳固定率的研究，这是限制这些生态系统生产最终需要的一种测量方法。虽然最近的数据表明硝酸盐还原成N2（反硝化）或NH4 +（硝酸盐的异化还原成铵，DNRA）可能是化学自养生产的重要原因，但在热液喷口的原位测量中从未测量过NO3 -还原速率。更广泛的影响：从这项拟议的工作中开发的喷口- tssid将提供给研究界，用于其他深海喷口。这笔拨款将资助两名研究生，一名在WHOI，另一名在布朗大学。这些pi还让本科生参与到他们的研究项目中，并计划继续这样做。西弗特博士目前参加了WHOI科技教育伙伴关系，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.