Prokaryote Communities at Active Chimney andIn SituColonization Devices After a Magmatic Degassing Event (37°N MAR, EMSO‐Azores Deep‐Sea Observatory)

Authors:
Open Access
Publisher website
Google Scholar
Abstract
The mixing zone between high‐temperature hydrothermal fluids and seawater produces redox gradients, promoting the development of unique ecosystems based on chemotrophy. The structure of microbial communities depends on their environment, which can vary according to space and time. Hydrothermal circulation within the oceanic crust determines the chemical composition and flow of fluids, depending on underground events (earthquakes, volcanic episodes, etc.) and impacts the development of microbial communities. This link between hydrothermal vent communities and deep geological events is the focus of the present study, the first of its kind for slow‐spreading ridge. In this study, we present a unique set of multidisciplinary data collected from 2008 to 2011 on the Eiffel Tower hydrothermal site (Lucky Strike vent field, Mid‐Atlantic Ridge, MAR). We benefit from continuous geophysical monitoring (temperature and seismicity) of the site, annual sampling of hydrothermal fluids (hot and diffuse) for geochemistry analyses, sampling of hydrothermal chimneys, and an in situ microbial colonization experiment over a year for microbial study. The high CO2content and concentrations of major elements (Cl, Ca, and Si) and SO4in the end‐member fluids collected in 2010 indicate that a magmatic degassing occurred between 2009 and 2010 under the Lucky Strike hydrothermal field. This is supported by the large temperature variations observed in March–April 2010. These magmatic CO2inputs seem to have affected microbial communities colonizing the high‐temperature chimney, as well as the basalts in the more diffuse and mixed zone, promoting the development of thermophilic/anaerobicArchaeaandBacteria(Archaeoglobales, Nautiliales, and Nitratiruptoraceae).
Funding Information
  • Centre National de la Recherche Scientifique
  • Institut Français de Recherche pour l'Exploitation de la Mer
  • Institut National des Sciences de l'Univers, Centre National de la Recherche Scientifique
  • Ministère de l'Education Nationale, de l'Enseignement Supérieur et de la Recherche

This publication has 133 references indexed in Scilit: