Carbon pool

Carbon pool is a reservoir of carbon in defined part of earth system. Carbon stock is absolute quantity of carbon in mass unit held within a pool at a specified time. Often "pool" and "stock" are used as synonyms.

Largest global carbon pools are earth crust mainly as sedimentary rocks (e.g. carbonates in limestone) and oceans mainly in the form of inorganic dissolved C. In terrestrial ecosystem carbon is mainly in organic form with largest stock in soil (1500...2000 Pg, 1 billion metric ton = 1 gigaton). Pool of living plants aboveground and root biomass is ca 560 Pg. In global scale studies smaller sub-pools (animals, microorganisms) are often ignored.