title: Long-term survey of heavy-metal pollution, biofilm contamination and diatom community structure in the Riou Mort watershed, South-West France.
abstract: In a metal-polluted stream in the Riou Mort watershed in SW France, periphytic biofilm was analyzed for diatom cell densities and taxonomic composition, dry weight and metal bio-accumulation (cadmium and zinc). Periphytic diatom communities were affected by the metal but displayed induced tolerance, seen through structural impact (dominance of small, adnate species) as well as morphological abnormalities particularly in the genera Ulnaria and Fragilaria. Species assemblages were characterized by taxa known to occur in metal-polluted environments, and shifts in the community structure expressed seasonal patterns: high numbers of Eolimna minima, Nitzschia palea and Pinnularia parvulissima were recorded in Summer and Autumn, whereas the species Surirella brebissonii, Achnanthidium minutissimum, Navicula lanceolata and Surirella angusta were dominant in Winter and Spring. Commonly used indices such as the Shannon diversity index and Specific Pollution Sensitivity Index reflected the level of pollution and suggest seasonal periodicity, the lowest diversities being observed in Summer.
authors.affiliation: Unité de Recherche Réseaux, Epuration et Qualité des Eaux REQE, Cemagref, Cestas Cedex, France. soizic.morin@bordeaux.cemagref.fr
authors.forename: S
authors.initials: S
authors.lastname: Morin
authors.forename: T T
authors.initials: TT
authors.lastname: Duong
authors.forename: A
authors.initials: A
authors.lastname: Dabrin
authors.forename: A
authors.initials: A
authors.lastname: Coynel
authors.forename: O
authors.initials: O
authors.lastname: Herlory
authors.forename: M
authors.initials: M
authors.lastname: Baudrimont
authors.forename: F
authors.initials: F
authors.lastname: Delmas
authors.forename: G
authors.initials: G
authors.lastname: Durrieu
authors.forename: J
authors.initials: J
authors.lastname: Schäfer
authors.forename: P
authors.initials: P
authors.lastname: Winterton
authors.forename: G
authors.initials: G
authors.lastname: Blanc
authors.forename: M
authors.initials: M
authors.lastname: Coste
mesh_terms: D000818:Animals; D018441:Biofilms; D002104:Cadmium / Q000032:analysis; D017377:Diatoms; D017753:Ecosystem; D004784:Environmental Monitoring / Q000295:instrumentation / Q000379:methods*; D056890:Eukaryota; D005602:France; D019216:Metals, Heavy / Q000032:analysis*; D012621:Seasons; D014872:Water Movements; D014874:Water Pollutants, Chemical / Q000032:analysis*; D015032:Zinc / Q000032:analysis
chemical_list: D019216:Metals, Heavy; D014874:Water Pollutants, Chemical; D002104:Cadmium; D015032:Zinc