Hydrothermal energy transfer and the ocean carbon cycling
N. Le Bris, UPMC - CNRS, France
Hydrothermal vents are considered isolated from the surrounding pelagic and benthic ecosystems. There are however several reasons to reconsider this idea. In the last 10 years the number of hydrothermal vent fields discovered on the seafloor has more than doubled, with a large number of the known vent fields lying on Arc and Back-Arc (ABA). Chemoautotrophy is known to set the base of the food web in a variety of habitats, that can extend far away from vents, and support microbial ecosystems in ecosystem as diverse as vent plume, hydrothermal sediments, or subseafloor ridge flanks. Furthermore, hydrothermal settings are now recognized to provide a significant contribution to global ocean biochemical processes. While deep-sea hydrothermal vent systems are increasingly explored, and their mineral resources considered for exploitation, their role in the broader deep-sea requires a reassessment. This presentation will consider the most recent knowledge on vent-derived chemosynthetic energy transfer in view of a better integration of deep-sea hydrothermal vent system in the larger picture of deep-ocean biogeochemistry and related ecosystem services. It will also contribute to identify gaps in the current understanding and set the frame for multidisciplinary and multiscale approaches.
