Turnover time of plant organic matter in the oceans

Range 2-6 days
Organism Biosphere
Reference Field CB, Behrenfeld MJ, Randerson JT, Falkowski P. Primary production of the biosphere: integrating terrestrial and oceanic components. Science. 1998 Jul 10 281(5374)237-40. p.238 middle column 2nd paragraphPubMed ID9657713
Primary Source P. G. Falkowski and J. A. Raven, Aquatic Photosynthesis (Blackwell, Oxford, UK, 1997). p.389 3rd paragraph
Method (Primary source p.389 3rd paragraph): "The average chlorophyll concentration of the world ocean is 0.32 mg/m^3 and the average euphotic zone depth is 63m. Thus, the average, integrated chlorophyll concentration is about 19mg/m^2 (Morel 1991). Carbon to chlorophyll ratios of phytoplankton typically range between 40:1 and 100:1 by weight (Banse 1977). Given the total area of the ocean of 3.1×10^8 km^2, the total carbon biomass in phytoplankton is between 0.25 to 0.65 Pg. If net primary production is about 50 Pg/yr, and assuming the ocean is in steady state (a condition [investigators] will discuss in more detail), the living phytoplankton biomass turns over between 60-150 times per year, which is equivalent to a turnover time of 2 to 6 days."
Comments Ref p.238 middle column 2nd paragraph:"Although primary producers in the ocean are responsible for nearly half of the biospheric NPP, they represent only 0.2% of global primary producer biomass (refs 3,16, 21). This uncoupling between NPP and biomass is a consequence of the more than three orders of magnitude faster turnover time of plant organic matter in the oceans (average 2 to 6 days) (primary source) than on land (average 19 years) (42)."
Entered by Uri M
ID 102947