utilize the materials produced by the autotrophic (and chemotrophic) organisms and via respiration will remineralise the compounds from the organic form back to inorganic, making them available for primary producers again. For most areas of the ocean, the highest rates of carbon remineralisation occur at depths between in the water column, decreasing down to about 1,200 m where remineralisation rates remain pretty constant at 0.1 μmol kg−1 yr−1. As a result of this, the pool of remineralised carbon (which generally takes the form of carbon dioxide) tends to increase in the photic zone. Most remineralisation is done with dissolved organic carbon (DOC). Studies have shown that it is larger sinking particles that transport matter down to the sea floor while suspended particles and dissolved organics are mostly consumed by remineralisation. This happens in part due to the fact that organisms must typically ingest nutrients smaller than they are, often by orders of magnitude. With the microbial community making up 90% of marine biomass, it is particles smaller than the microbes (on the order of ) that will be taken up for remineralisation. See also Biological pump Decomposition f-ratio John D. Hamaker (soil remineralisation) Mineralization (biology) Mineralization (soil science) Immobilization (soil science) References Biogeochemistry Oceanography Limnology