TY - JOUR
T1 - Buffering of Ocean Export Production by Flexible Elemental Stoichiometry of Particulate Organic Matter
AU - Tanioka, Tatsuro
AU - Matsumoto, Katsumi
PY - 2017/10
Y1 - 2017/10
N2 - One of the most important factors that determine the ocean-atmosphere carbon partitioning is the sinking of particulate organic matter (POM) from the surface ocean to the deep ocean. The amount of carbon (C) removed from the surface ocean by this POM export production depends critically on the elemental ratio in POM of C to nitrogen (N) and phosphorus (P), two essential elements that limit productivity. Recent observations indicate that P:N:C in marine POM varies both spatially and temporally due to chemical, physical, and ecological dynamics. In a new approach to predicting a flexible P:C ratio, we developed a power law model with a stoichiometry sensitivity factor, which is able to relate P:C of POM to ambient phosphate concentration. The new factor is robust, measurable, and biogeochemically meaningful. Using the new stoichiometry sensitivity factor, we present a first-order estimate that P:C plasticity could buffer against a generally expected future reduction in global carbon export production by up to 5% under a future warming scenario compared to a fixed, Redfield P:C. Further, we demonstrate that our new stoichiometry model can be implemented successfully and easily in a global model to reproduce the large-scale P:N:C variability in the ocean.
AB - One of the most important factors that determine the ocean-atmosphere carbon partitioning is the sinking of particulate organic matter (POM) from the surface ocean to the deep ocean. The amount of carbon (C) removed from the surface ocean by this POM export production depends critically on the elemental ratio in POM of C to nitrogen (N) and phosphorus (P), two essential elements that limit productivity. Recent observations indicate that P:N:C in marine POM varies both spatially and temporally due to chemical, physical, and ecological dynamics. In a new approach to predicting a flexible P:C ratio, we developed a power law model with a stoichiometry sensitivity factor, which is able to relate P:C of POM to ambient phosphate concentration. The new factor is robust, measurable, and biogeochemically meaningful. Using the new stoichiometry sensitivity factor, we present a first-order estimate that P:C plasticity could buffer against a generally expected future reduction in global carbon export production by up to 5% under a future warming scenario compared to a fixed, Redfield P:C. Further, we demonstrate that our new stoichiometry model can be implemented successfully and easily in a global model to reproduce the large-scale P:N:C variability in the ocean.
KW - biogeochemical cycles, processes, and modeling
KW - carbon cycling
KW - phytoplankton
UR - http://www.scopus.com/inward/record.url?scp=85031732024&partnerID=8YFLogxK
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U2 - 10.1002/2017GB005670
DO - 10.1002/2017GB005670
M3 - Article
AN - SCOPUS:85031732024
VL - 31
SP - 1528
EP - 1542
JO - Global Biogeochemical Cycles
JF - Global Biogeochemical Cycles
SN - 0886-6236
IS - 10
ER -