The graph is showing how primary production decreases as deep increases. It is due to the amount of available light in the water.
<h3>Primary production on the ocean</h3>
The primary production in the ocean is performed by microorganisms known as phytoplankton.
Phytoplankton populations are primary producers that include bacteria and algae, which use photosynthesis to produce biomass and release oxygen.
In a similar manner to plants, phytoplankton communities also contain chlorophyll in order to convert sunlight into biomass.
As ocean deep increases, the amount of available light in the water decreases, thereby also decreasing the primary production of the phytoplankton populations.
Learn more about primary production here:
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