Net primary productivity (NPP)
Definition
The amount of carbon retained in an ecosystem (increase in biomass); it is equal to the difference between the amount of carbon produced through photosynthesis (GPP) and the amount of energy that is used for respiration (R).
Source
Glossary. M.S. Ashton et al. (eds.), Managing Forest Carbon in a Changing Climate,DOI 10.1007/978-94-007-2232-3, © Springer Science+Business Media B.V. 2012