Aquatic ecology and Biodiversity

Unit 5- Productivity

5.3.1. Net ecosystem production
NEP is the net amount of primary production after the costs of respiration by plants, heterotrophs and decomposers are all included. Therefore,
NEP = GPP - (R_p + R_h + R_d)
R_p =Respiration by autotrophs; R_h = Respiration by heterotrophs; R_d = Respiration by decomposers.

Note : Secondary production is the gain in biomass or reproduction of heterotrophs and decomposers. The rates of secondary production are very much lower than the rates of primary production.