Minerals Report - International Seabed Authority

Figure 2 Simplified representation of major components involved in the production and consumption of
organic matter in hydrothermal vent ecosystems. A food chain is based on organic matter produced by
free-living and chemosynthetic microbes. Some food may be exported to the surrounding deep sea.
Other hydrothermal habitats
Microbial chemosynthesis also occurs in subsurface hydrothermal
conduits 5 , and in the plumes 6 that overlie vent fields, but faunal exploitation
of microbial biomass produced in these two environments has not been
extensively examined. Interaction between biological and geochemical
processes has been most clearly documented in hydrothermal plumes. For
example, recent studies show that oxidation of dissolved manganese in
hydrothermal plumes is mostly microbial mediated 6, 7 . High concentrations of
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