The protection of the deep-sea ecosystems, the largest biome on the planet, is crucial for future generations and requires ambitious research projects. The deep ocean, covering more than 70% of the Earth’s surface, is a major source of oxygen and carbon dioxide absorption. It has attracted the attention of countries for its biodiversity and mineral resources, particularly in hydrothermal contexts. It is urgent to establish solid knowledge bases to manage these ecosystems within an interconnected framework.
Since 2014, our studies have focused on the hydrothermal fields of TAG and Snake Pit, located 3,600 meters deep on the Mid-Atlantic Ridge. These sites, separated by a transform fault, exhibit biological similarities and raise questions about their connectivity. Three oceanographic campaigns have allowed us to identify habitats and begin studying key species. Geochemical anomalies in the water column have revealed uncharted active hydrothermal fields, which are essential for understanding species dispersion.
In this project, we will develop integrated approaches to study the geological, geochemical, and biological functioning of deep-sea ecosystems. The work is divided into several components: • Exploration of ecosystem services related to sulfide deposits (WP2). • Study of the biogeochemical impacts of the hydrothermal plume in the deep ocean (WP3). • Study of the resilience and connectivity of communities (WP4). • Public outreach through workshops and citizen science (WP5).
Our research aims to provide data to understand the functioning of these environments, from both a geological and biological perspective. Our work aims to assist governments in legislating access to and the use of deep-sea waters based on informed decisions for sustainable management.

Funding: PPR Océan et Climat, Un océan de solutions - France 2030 : ANR-22-POCE-0007

Project coordinator: Marie-Anne Cambon, Ifremer, Marie.Anne.Cambon@ifremer.fr