title: Before-After analysis of the trophic network of an experimental dumping site in the eastern part of the Bay of Seine (English Channel).
abstract: An experimental study was conducted to assess the physical and biological impacts of muddy fine sand dredged material dumped on a medium sand site Machu offshore the Seine Estuary. Complementary trophic web modelling tools were applied to the Machu ecosystem to analyse the effects of dumping operations. Results show that, after the dumping operations, the biomass of fish increased while invertebrate biomass remained relatively stable through time. Nevertheless, the biomasses of benthic invertebrates, omnivores/scavengers and predators showed some increases, while non-selective deposit feeders and filter feeders decreased. At the ecosystem level, results show that the total ecosystem activity, the ascendency and the overall omnivorous character of the food-web structure increased after dumping operations, whereas recycling subsequently decreased. Finally, the fine and medium sand habitat offshore from the Seine estuary, which undergoes regular natural physical perturbations, shows a high resilience after a short dumping phase.
authors.affiliation: Normandie Univ., UNICAEN, UNIROUEN, CNRS UMR 6143 M2C, Laboratoire Morphodynamique Continentale et Côtière, 24 rue des Tilleuls, 14000 Caen, France. Electronic address: jean-philippe.pezy@unicaen.fr.
authors.forename: Jean-Philippe
authors.initials: JP
authors.lastname: Pezy
authors.affiliation: Normandie Univ., UNICAEN, UNIROUEN, CNRS UMR 6143 M2C, Laboratoire Morphodynamique Continentale et Côtière, 24 rue des Tilleuls, 14000 Caen, France; Normandie Univ., UNICAEN, UMR BOREA (MNHN, UPMC, CNRS-7208, IRD-207), Esplanade de la Paix, 14032 Caen CEDEX 5, France.
authors.forename: Aurore
authors.initials: A
authors.lastname: Raoux
authors.affiliation: Normandie Univ., UNICAEN, UNIROUEN, CNRS UMR 6143 M2C, Laboratoire Morphodynamique Continentale et Côtière, 24 rue des Tilleuls, 14000 Caen, France.
authors.forename: Stella
authors.initials: S
authors.lastname: Marmin
authors.affiliation: Cellule de Suivi du Littoral Normand, CSLN, 53 Rue de Prony, 76600 Le Havre, France.
authors.forename: Pierre
authors.initials: P
authors.lastname: Balay
authors.affiliation: Normandie Univ., UNICAEN, UMR BOREA (MNHN, UPMC, CNRS-7208, IRD-207), Esplanade de la Paix, 14032 Caen CEDEX 5, France.
authors.forename: Nathalie
authors.initials: N
authors.lastname: Niquil
authors.affiliation: Normandie Univ., UNICAEN, UNIROUEN, CNRS UMR 6143 M2C, Laboratoire Morphodynamique Continentale et Côtière, 24 rue des Tilleuls, 14000 Caen, France.
authors.forename: Jean-Claude
authors.initials: JC
authors.lastname: Dauvin
mesh_terms: D000818:Animals; D061006:Bays; D018533:Biomass; D004784:Environmental Monitoring; D004787:Environmental Pollution; D063366:Estuaries; D005399:Fishes; D020387:Food Chain; D005602:France; D019015:Geologic Sediments; D007448:Invertebrates; D012037:Refuse Disposal
keywords: Bay of Seine; Dredged material disposal; Ecological Network Analysis; Ecopath; Trophic model