%0 Journal Article %J Marine Environmental Research %D 2019 %T Trophic importance of microphytobenthos and bacteria to meiofauna in soft-bottom intertidal habitats: A combined trophic marker approach %A van der Heijden, L.H. %A Graeve, M. %A R. Asmus %A Rzeznik-Orignac, J. %A Nathalie Niquil %A Bernier, Q. %A Guillou, G. %A H Asmus %A Lebreton, B. %K Article %K Bacillariophyta %K bacteria %K bacterium %K Benthic copepods %K Benthic diatoms %K Biological materials %K biomarker %K Biomass %K carbon 13 %K coastal zone %K controlled study %K Copepoda %K delta carbon 13 %K delta nitrogen 15 %K Diatom %K Ecosystems %K fatty acids %K Feeding Behavior %K food supply %K France %K Free livings %K Freeze Drying %K Frisian Islands %K Germany %K high performance liquid chromatography %K intertidal environment %K isotope analysis %K Isotopes %K lipid composition %K Marennes-Oleron Bay %K Meiofauna %K microbial activity %K Microphytobenthos %K mudflat %K Mudflats %K Nematoda %K nitrogen 15 %K nonhuman %K North Frisian Islands %K Nouvelle-Aquitaine %K Organic matter %K Phytobenthos %K Plants (botany) %K Sandflats %K seagrass %K Seagrass beds %K Sediment %K soft-bottom environment %K species habitat %K substrate %K suspended particulate organic matter %K Sylt-Romo Bight %K trophic environment %K Trophic markers %K Trophic structure %K unclassified drug %X Meiofauna can play an important role in the carbon fluxes of soft-bottom coastal habitats. Investigation of their feeding behavior and trophic position remains challenging due to their small size. In this study, we determine and compare the food sources used by nematodes and benthic copepods by using stable isotope compositions, fatty acid profiles and compound specific isotope analyses of fatty acids in the mudflats, seagrass beds and a sandflat of the Marennes-Oléron Bay, France, and the Sylt-Rømø Bight, Germany. Suspended particulate organic matter was much more 13C-depleted than other food sources and meiofauna, highlighting its poor role in the different studied habitats. The very low proportions of vascular plant fatty acid markers in meiofauna demonstrated that these consumers did not rely on this food source, either fresh or detrital, even in seagrass beds. The combined use of stable isotopes and fatty acids emphasized microphytobenthos and benthic bacteria as the major food sources of nematodes and benthic copepods. Compound specific analyses of a bacteria marker confirmed that bacteria mostly used microphytobenthos as a substrate. © 2019 Elsevier Ltd %B Marine Environmental Research %I Elsevier Ltd %V 149 %P 50-66 %G eng %U https://www.sciencedirect.com/science/article/abs/pii/S0141113618304744 %R 10.1016/j.marenvres.2019.05.014