海底熱水系の物理・化学的多様性と化学合成微生物生態系の存在様式

抄録

 Deep-sea hydrothermal vents are among the habitats that host the most diverse microbial communities on the Earth. It is promised that hydrothermal vent microbial communities play a major role in the circulation of energy and materials in the global oceanic and suboceanic environments, and even provide important insights into the origin and early evolution of life on the Earth and extraterrestrial life on other planets and moons. Deep-sea hydrothermal vent ecosystems are strongly dependent on the primary production of symbiotic and free-living chemolithoautotrophic microorganisms that can obtain energy from inorganic substances such as H₂S, CO₂, H₂, and CH₄ derived from hydrothermal vent fluids. The diversity and abundance of these energy and carbon sources at hydrothermal vent fluids are, in turn, controlled by subseafloor physical and chemical processes such as fluid–rock interactions and phase-separation and -partition of fluids. Therefore, linkage between rock (magma), hydrothermal fluid, and ecosystem is a key to understanding how deep-sea hydrothermal ecosystems are generated and sustained. In this article, we approach this whole “Rock–Fluid–Ecosystem linkage” with the two separate sub-linkages of “Rock–Fluid linkage” and “Fluid–Ecosystem linkage”, which have not been addressed by the individual research fields of the Geochemistry of Hydrothermal Systems and Hydrothermal Vent Microbiology, respectively. Here, we overview the progress of understanding the “Rock–Fluid” and “Fluid–Ecosystem” linkages, both of which will establish the basis for an integrated “Rock–Fluid–Ecosystem linkage”.
 
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