Differential effects of elevated p CO 2 and warming on marine phytoplankton stoichiometry

Phytoplankton stand at the base of marine food-web, and play a major role in global carbon cycling. Rising CO2 levels temperatures are expected to enhance growth alter carbon:nutrient stoichiometry phytoplankton, with possible consequences for functioning food-webs oceanic pump. To date, however, consistency phytoplankton stoichiometric responses remains unclear. We therefore performed meta-analysis on data from experimental studies elevated pCO2 3–5° warming under nutrient replete limited conditions. Our results demonstrate that increased overall C:N (by 4%) C:P 9%) molar ratios conditions, as well rates 6%). Nutrient limitation amplified effect ratios, increases 27% 17%, respectively. In contrast pCO2, did not consistently elemental composition. This could be attributed species- study-specific decreases response warming. While our observed moderate CO2-driven changes likely drive marked food web functioning, they same order magnitude current projected estimations export. Therefore, may indicate compensation mechanism reduced export due declining primary production near future.