net_primary_mole_productivity_of_biomass_expressed_as_nitrogen_by_nanophytoplankton mol m-2 s-1 [M2MS] Vertically integrated primary (organic carbon) production by the nanophytoplankton component alone. Net primary production is the excess of gross primary production (rate of synthesis of biomass from inorganic precursors) by autotrophs ("producers"), for example, photosynthesis in plants or phytoplankton, over the rate at which the autotrophs themselves respire some of this biomass. "Productivity" means production per unit area. The phrase "expressed_as" is used in the construction "A_expressed_as_B", where B is a chemical constituent of A. It means that the quantity indicated by the standard name is calculated solely with respect to the B contained in A, neglecting all other chemical constituents of A. Total nitrogen means nitrogen in all chemical forms. Nanophytoplankton are phytoplankton in the size range 2 – 20 micrometers. Phytoplankton are algae that grow where there is sufficient light to support photosynthesis.