%0 Journal Article
%9 ACL : Articles dans des revues avec comité de lecture répertoriées par l'AERES
%A Hunt, B. P. V.
%A Carlotti, F.
%A Donoso, K.
%A Pagano, Marc
%A D'Ortenzio, F.
%A Taillandier, V.
%A Conan, P.
%T Trophic pathways of phytoplankton size classes through the zooplankton food web over the spring transition period in the north-west Mediterranean Sea
%D 2017
%L fdi:010071051
%G ENG
%J Journal of Geophysical Research : Oceans
%@ 2169-9275
%K zooplankton ; isotopes ; food web ; phytoplankton ; trophic pathways
%K MEDITERRANEE
%M ISI:000410790600015
%N 8
%P 6309-6324
%R 10.1002/2016jc012658
%U https://www.documentation.ird.fr/hor/fdi:010071051
%> https://www.documentation.ird.fr/intranet/publi/2017/10/010071051.pdf
%V 122
%W Horizon (IRD)
%X Knowledge of the relative contributions of phytoplankton size classes to zooplankton biomass is necessary to understand food-web functioning and response to climate change. During the Deep Water formation Experiment (DEWEX), conducted in the north-west Mediterranean Sea in winter (February) and spring (April) of 2013, we investigated phytoplankton-zooplankton trophic links in contrasting oligotrophic and eutrophic conditions. Size fractionated particulate matter (pico-POM, nano-POM, and micro-POM) and zooplankton (64 to >4000 mu m) composition and carbon and nitrogen stable isotope ratios were measured inside and outside the nutrient-rich deep convection zone in the central Liguro-Provencal basin. In winter, phytoplankton biomass was low (0.28 mg m(-3)) and evenly spread among picophytoplankton, nanophytoplankton, and microphytoplankton. Using an isotope mixing model, we estimated average contributions to zooplankton biomass by pico-POM, nano-POM, and micro-POM of 28, 59, and 15%, respectively. In spring, the nutrient poor region outside the convection zone had low phytoplankton biomass (0.58 mg m(-3)) and was dominated by pico/nanophytoplankton. Estimated average contributions to zooplankton biomass by pico-POM, nano-POM, and micro-POM were 64, 28 and 10%, respectively, although the model did not differentiate well between pico-POM and nano-POM in this region. In the deep convection zone, spring phytoplankton biomass was high (1.34 mg m(-3)) and dominated by micro/nano phytoplankton. Estimated average contributions to zooplankton biomass by pico-POM, nano-POM, and micro-POM were 42, 42, and 20%, respectively, indicating that a large part of the microphytoplankton biomass may have remained ungrazed.
%$ 036