Studies on the Physiological Ecology of Hydrothermal Vent Chemoautotrophic Symbioses

与深海热液喷口有关的动物代表了海洋中全球分布的古老动物群。这些群落的存在取决于一些无脊椎动物/细菌共生组织的能力，它们利用来自周围深海的氧化剂（如氧或硝酸盐）氧化热液喷口的还原性化学物质（硫化物或甲烷），为这种环境中的初级生产提供动力。共生关系与喷口环境的化学性质的相互作用能力是支持这些生态系统的初级生产的基础。该项目的中心目标是确定二氧化碳浓度（PCO2）作为影响热液喷口化学自养共生初级生产速率的环境因素的重要性。该项目由三个部分组成，每个部分都有自己的目标：对不同的通风口和渗漏环境进行调查，以确定这些栖息地中化学自养共生生物暴露于高浓度二氧化碳和体内高浓度二氧化碳的程度。2. 船上研究支持共生喷口动物初级生产力的生理，以评估二氧化碳浓度是否是一个限制共生关系初级生产力的变量。3. 为了描述长时间尺度的共生生态位，以评估这些环境中初级生产力的长期比率，在13oN的一个站点进行了时间变化的观测和测量。该项目将极大地增加我们对喷口动物与其化学环境之间相互作用的本质的理解，特别是与pH和无机碳的相互作用，有助于我们理解喷口和其他化学自养支持生态系统的功能。＊＊＊

9301374 CHILDRESS The animals associated with deep-sea hydrothermal vents represent an ancient fauna of global distribution within the oceans. The very existence of these communities depends upon the ability of a few invertebrate/bacterial symbiotic associations to oxidize the reduced chemical species (sulfide or methane) from the hydrothermal vents using oxidants (such as oxygen or nitrate) from the surrounding deep-sea water to power primary production in this environment. The capacity for interaction of the symbiotic association with the chemical properties of the vent environments is fundamental to the primary production which supports these ecosystems. The central objective of this project is the determination of the importance of the concentration of carbon dioxide (PCO2) as an environmental factor affecting the rates of primary production by hydrothermal vent chemoautotrophic symbioses. This project is composed of there components, each with its own objectives: 1. A survey of diverse vent and seep environments to determine the extent to which chemoautotrophic symbioses in these habitats are exposed to elevated carbon dioxide and have high concentrations of carbon dioxide in their bodies. 2. Shipboard studies of the physiology supporting primary productivity in symbiotic vent animals in order to evaluate whether the concentration of carbon dioxided is a variable which limits primary production by the symbiotic associations. 3. The observation and measurement of temporal changes at a station located at 13oN in order to describe the niches of the symbioses over long time scales to assess long term rates of primary productivity in these environments. This project will greatly increase our understanding of the nature of the interactions between the vent animals and their chemical environment, in particular the interactions with pH and inorganic carbon, contributing to our understanding of the functioning of the vent and other chemoautotrophic ally supported ecosystems. ***