BIOL1012 Lecture Notes - Lecture 29: Chemosynthesis, Autotroph, Photic Zone
Document Summary
Net primary production (npp) = gpp - ra: npp is the amount of energy/matter available to consumers in an ecosystem. Figure 55. 10: this primary (1o) consumer might use ~50% of the energy represented by the plant material ingested, and pass half as feces, production efficiency is the ingested amount that is stored as growth, production efficiency here is. 0: estimates vary but global npp is ~100-110 gt c y-1, 100 x 1015 g c y-1 (100 000 000 000 000 000, 100 petagrams, split roughly equally between terrestrial and ocean systems. A few specifics, just because: marine phytoplankton account for ~50 x 1015 grams c per year (50 billion tonnes) of npp, marine coastal production is much higher than open ocean productivity, ~20x on a water volume basis, ~5x on an area basis. Chavez et al. (2011) annual review of marine science 3:227-60. A few specifics, just because: tropical forest npp estimates range from 3-30.
