title: Do the levels of industrial pollutants influence the distribution and abundance of dinoflagellate cysts in the recently-deposited sediment of a Mediterranean coastal ecosystem?
abstract: We studied the relationships between sediment industrial pollutants concentrations, sediment characteristics and the dinoflagellate cyst abundance within a coastal lagoon by investigating a total of 55 sampling stations within the Bizerte lagoon, a highly anthropized Mediterranean ecosystem. The sediment of Bizerte lagoon is characterized by a high dinocyst abundance, reaching a maximum value of 2742cysts·g-1of dry sediment. The investigated cyst diversity was characterized by the presence of 22 dominant dinocyst morphotypes belonging to 11 genera. Two dinoflagellate species dominated the assemblage: Alexandrium pseudogonyaulax and Protoperidinium claudicans, representing 29 to 89% and 5 to 38% of the total cyst abundance, respectively, depending on the station. Seven morphotypes belonging to potentially toxic species were detected, including Alexandrium minutum, A. pseudogonyaulax, Alexandrium catenella/tamarense species complex, Lingulodinium polyedrum, Gonyaulax cf. spinifera complex, Prorocentrum micans and Protoceratium reticulatum. Pearson correlation values showed a positive correlation (α=0.05) between cyst abundance and both water content and fine silt sediment content. Clustering revealed that the highest abundance of cysts corresponds to stations presenting the higher amounts of heavy metals. The simultaneous autoregressive model (SAM) highlighted a significant correlation (α=0.05) between cyst accumulation and two main factors: sediment water content and sediment content for several heavy metals, including Hg, Cd, Cu, Ni and Cr. These results suggest that the degree of heavy metal pollution could influence cyst accumulation patterns.
authors.affiliation: Institut Nationale Agronomique de Tunisie (INAT), IRESA - Université de Carthage, U.R Biologie Marine (FST El Manar I), 43 Avenue Charles Nicolle, 1082 Tunis, Tunisia. Electronic address: bibarouma@hotmail.fr.
authors.forename: Habiba Zmerli
authors.initials: HZ
authors.lastname: Triki
authors.affiliation: Laboratoire Ecologie des Systèmes Marins Côtiers (ECOSYM), UMR 5119 UM2-CNRS-IRD-IFREMER-UM1, Université Montpellier, Place Eugène Bataillon, 34095 Montpellier, France.
authors.forename: Mohamed
authors.initials: M
authors.lastname: Laabir
authors.affiliation: UMR 9190 MARBEC IRD-Ifremer-CNRS-Université de Montpellier, Place Eugène Bataillon, Case 093, 34095 Montpellier Cedex 5, France; Faculté des Sciences de Bizerte, Université de Carthage, 7021 Zarzouna, Tunisia.
authors.forename: Céline
authors.initials: C
authors.lastname: Lafabrie
authors.affiliation: Ecole Supérieure de la Statistique et de l'Analyse de l'Information, Tunisia.
authors.forename: Dhafer
authors.initials: D
authors.lastname: Malouche
authors.affiliation: UMR 5569 HydroSciences IRD-CNRS-Université de Montpellier, 163 rue Auguste Broussonnet, 34090 Montpellier, France.
authors.forename: Chrystelle
authors.initials: C
authors.lastname: Bancon-Montigny
authors.affiliation: Ecole des Mines d'Alès, LGEI, 6 Avenue de Clavîeres, 30319 Alès Cedex, France.
authors.forename: Catherine
authors.initials: C
authors.lastname: Gonzalez
authors.affiliation: Department of Geosciences, Université de Malte, Msida, Malta.
authors.forename: Alan
authors.initials: A
authors.lastname: Deidun
authors.affiliation: UMR 9190 MARBEC IRD-Ifremer-CNRS-Université de Montpellier, Place Eugène Bataillon, Case 093, 34095 Montpellier Cedex 5, France; Faculté des Sciences de Bizerte, Université de Carthage, 7021 Zarzouna, Tunisia.
authors.forename: Olivier
authors.initials: O
authors.lastname: Pringault
authors.affiliation: Institut Nationale Agronomique de Tunisie (INAT), IRESA - Université de Carthage, U.R Biologie Marine (FST El Manar I), 43 Avenue Charles Nicolle, 1082 Tunis, Tunisia.
authors.forename: Ons Kéfi
authors.initials: OK
authors.lastname: Daly-Yahia
mesh_terms: D004141:Dinoflagellida / Q000187:drug effects*; D017753:Ecosystem; D004784:Environmental Monitoring; D019015:Geologic Sediments / Q000737:chemistry*; D008522:Mediterranean Sea; D014416:Tunisia; D014874:Water Pollutants, Chemical / Q000032:analysis*
chemical_list: D014874:Water Pollutants, Chemical
keywords: Dinocyst assemblage; Interaction pollutants/cysts; Mediterranean Bizerte Lagoon; Organic/inorganic contaminants; Spatial distribution; Toxic/noxious species