05.02.2013 Views

Minerals Report - International Seabed Authority

Minerals Report - International Seabed Authority

Minerals Report - International Seabed Authority

SHOW MORE
SHOW LESS

Create successful ePaper yourself

Turn your PDF publications into a flip-book with our unique Google optimized e-Paper software.

Figure1: Schematic representation of the biogeochemical relationship between the photosynthetic<br />

production of organic matter in the surface ocean and the chemosynthesis of organic matter at deep-sea<br />

hydrothermal vents. In photosynthesis, solar energy is used to fix CO2 into organic material while<br />

microbes at vents use energy derived from the oxidation of hydrogen sulphide (H2S) for the same purpose.<br />

Since hydrothermal fluids are formed by reaction of seawater with hot<br />

rock, researchers quickly realized that vent ecosystems were ultimately<br />

powered by heat from the earth’s mantle. This was a startling conceptual<br />

challenge to the long held view that all of our planet’s ecosystems require<br />

sunlight and photosynthesis to create new biomass and nourish animal food<br />

chains.<br />

Vent ecosystems are not completely independent of sunlight. All<br />

animals and many microorganisms at vents require dissolved oxygen for their<br />

metabolism (Table 1).<br />

INTERNATIONAL SEABED AUTHORITY 275

Hooray! Your file is uploaded and ready to be published.

Saved successfully!

Ooh no, something went wrong!