1. Estimating ecosystem metabolism from continuous multi-sensor measurements in the Seine River
- Author
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Nicolas Escoffier, Nathaniel Bensoussan, Nicolas Flipo, Alexis Groleau, A. David, François Métivier, Lauriane Vilmin, Vincent Rocher, Institut de Physique du Globe de Paris (IPGP), Centre National de la Recherche Scientifique (CNRS)-Université de La Réunion (UR)-Université Paris Diderot - Paris 7 (UPD7)-IPG PARIS-Institut national des sciences de l'Univers (INSU - CNRS), IPSO FACTO, SCOPARL, Pôle Océanologie et Limnologie, Centre de Géosciences (GEOSCIENCES), MINES ParisTech - École nationale supérieure des mines de Paris-PSL Research University (PSL), SIAAP - Direction du Développement et de la Prospective, SIAAP, Institut de Génomique Fonctionnelle - Montpellier GenomiX (IGF MGX), Institut de Génomique Fonctionnelle (IGF), Université de Montpellier (UM)-Université Montpellier 1 (UM1)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Université Montpellier 2 - Sciences et Techniques (UM2)-Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-Université Montpellier 1 (UM1)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Université Montpellier 2 - Sciences et Techniques (UM2)-Centre National de la Recherche Scientifique (CNRS), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-IPG PARIS-Université Paris Diderot - Paris 7 (UPD7)-Université de La Réunion (UR)-Centre National de la Recherche Scientifique (CNRS), IPGP, Université Paris Diderot - Paris 7 (UPD7), Milieux Environnementaux, Transferts et Interactions dans les hydrosystèmes et les Sols (METIS), Centre National de la Recherche Scientifique (CNRS)-École pratique des hautes études (EPHE)-Université Pierre et Marie Curie - Paris 6 (UPMC), Siaap - Direction du développement et de la prospective, NKE instrumentation, entreprise, Institut national des sciences de l'Univers (INSU - CNRS)-IPG PARIS-Université de La Réunion (UR)-Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP), IPSO FACTO [Marseille], MINES ParisTech - École nationale supérieure des mines de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL), École pratique des hautes études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Geochemistry, and Bio-, hydro-, and environmental geochemistry
- Subjects
0106 biological sciences ,Ecosystem respiration ,010504 meteorology & atmospheric sciences ,Health, Toxicology and Mutagenesis ,[SDE.MCG]Environmental Sciences/Global Changes ,[SDU.STU]Sciences of the Universe [physics]/Earth Sciences ,01 natural sciences ,Continuous monitoring ,Phytoplankton ,Environmental Chemistry ,River metabolism ,Ecosystem ,14. Life underwater ,Continuous monitoring . River metabolism . Primary production . Ecosystemrespiration . Phytoplankton . Urban pressures ,[SDU.STU.HY]Sciences of the Universe [physics]/Earth Sciences/Hydrology ,ComputingMilieux_MISCELLANEOUS ,0105 earth and related environmental sciences ,Hydrology ,Primary production ,010604 marine biology & hydrobiology ,General Medicine ,Plankton ,Annual cycle ,Pollution ,6. Clean water ,Productivity (ecology) ,13. Climate action ,[SDE]Environmental Sciences ,Environmental science ,Urban pressures ,Eutrophication - Abstract
International audience; Large rivers are important components of the global C cycle. While they are facing an overall degradation of their water quality, little remains known about the dynamics of their metabolism. In the present study, we used continuous multi-sensors measurements to assess the temporal variability of gross primary production (GPP) and ecosystem respiration (ER) rates of the anthropized Seine River over an annual cycle. Downstream from the Paris urban area, the Seine River is net heterotrophic at the annual scale (−226 gO2m−2 year−1 or −264 gC m−2 year−1). Yet, it displays a net autotrophy at the daily and seasonal scales during phytoplankton blooms occurring from late winter to early summer. Multivariate analyseswere performed to identify the drivers of river metabolism. Daily GPP is best predicted by chlorophyll a (Chla), water temperature (T), light, and rainfalls, and the coupling of daily GPP and Chla allows for the estimation of the productivity rates of the different phytoplankton communities. ER rates are mainly controlled by T and, to a lesser extent, by Chla. The increase of combined sewer overflows related to storm events during the second half of the year stimulates ER and the net heterotrophy of the river. River metabolism is, thus, controlled at different timescales by factors that are affected by human pressures. Continuous monitoring of river metabolism must, therefore, be pursued to deepen our understanding about theresponses of ecosystem processes to changing human pressures and climate.
- Published
- 2018
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