title: Achnanthidium minutissimum (Bacillariophyta) valve deformities as indicators of metal enrichment in diverse widely-distributed freshwater habitats.
abstract: In the presence of different environmental stressors, diatoms can produce frustules presenting different types of deformities. Metals and trace elements are among the most common causes of these teratological forms. Metal enrichment in water bodies can be attributed to the geological setting of the area or to pollution. The widespread benthic diatom Achnanthidium minutissimum (ADMI) is one of the most metal-tolerant species. In the present study, ADMI teratologies were defined from samples taken from eight very diverse, widely-distributed inland-water habitats: streams affected by active and abandoned mining areas, a metal-contaminated stream, a spring in an old chalcopyrite mine, a mineral-water fountain, and a sediment core taken from a lake affected by metal contamination in the past. Deformed frustules of ADMI were characterised mainly by one (sometimes two) more or less bent off ending, conferring to the specimens a cymbelloid outline (cymbelliclinum-like teratology, CLT). Marked teratologies were distinguished from slight deformities. Hydrochemical analyses, including metals and trace elements, were carried out and enrichment factors (EF) relative to average crustal composition were calculated. To improve our knowledge on the potential of different metals and trace elements to trigger the occurrence of ADMI CLT, we carefully selected 15 springs out of 110 (CRENODAT dataset) where both ADMI and above-average metal or metalloid concentrations occurred, and re-analysed these samples. The results from the eight widely-distributed core sites as well as from the 15 selected CRENODAT springs led to the hypothesis that two metals (copper and zinc) and a metalloid (antimony) were the most likely triggers of ADMI CLT formation. From a quantitative point of view, it is worth noting that the lowest concentrations triggering ADMI CLT can be fairly low, particularly in the case of copper contamination. The antimony-rich site was characterised by a marked-teratology variant where both ends of ADMI were bent off.
authors.affiliation: Museo delle Scienze - MUSE, Limnology and Phycology Research Unit, Corso del Lavoro e della Scienza 3, I-38123 Trento, Italy. Electronic address: marco.cantonati@muse.it.
authors.forename: Marco
authors.initials: M
authors.lastname: Cantonati
authors.affiliation: Museo delle Scienze - MUSE, Limnology and Phycology Research Unit, Corso del Lavoro e della Scienza 3, I-38123 Trento, Italy.
authors.forename: Nicola
authors.initials: N
authors.lastname: Angeli
authors.affiliation: University of Helsinki, Dept. of Environmental Sciences, Aquatic Community Ecology Group, Biocenter 3, Viikinkaari 1, P.O. Box 65, FI-00014 Helsinki, Finland.
authors.forename: Laura
authors.initials: L
authors.lastname: Virtanen
authors.affiliation: Polish Academy of Sciences, Institute of Botany, Lubicz 46, 31-512 Kraków, Poland.
authors.forename: Agata Z
authors.initials: AZ
authors.lastname: Wojtal
authors.affiliation: University Ca' Foscari of Venice, IDPA-CNR, Calle Larga Santa Marta, 2137, 30123 Venice, Italy.
authors.forename: Jacopo
authors.initials: J
authors.lastname: Gabrieli
authors.affiliation: University of Turin, Dipartimento di Scienze della Vita e Biologia dei Sistemi, Laboratorio di Ecologia, Via Accademia Albertina 13, 10123 Torino, Italy.
authors.forename: Elisa
authors.initials: E
authors.lastname: Falasco
authors.affiliation: Institut National de la Recherche Scientifique, Centre Eau Terre Environnement, 490 de la Couronne, Québec, Québec G1K 9A9, Canada.
authors.forename: Isabelle
authors.initials: I
authors.lastname: Lavoie
authors.affiliation: Irstea, UR REBX, 50 Avenue de Verdun, 33612 Cestas Cedex, France.
authors.forename: Soizic
authors.initials: S
authors.lastname: Morin
authors.affiliation: CNR Institute of Ecosystem Study, L.go Tonolli 50, I 28922 Verbania Pallanza, Italy.
authors.forename: Aldo
authors.initials: A
authors.lastname: Marchetto
authors.affiliation: Institut National de la Recherche Scientifique, Centre Eau Terre Environnement, 490 de la Couronne, Québec, Québec G1K 9A9, Canada.
authors.forename: Claude
authors.initials: C
authors.lastname: Fortin
authors.affiliation: Komarov Botanical Institute RAS, Professor Popov Street 2, 197376, St. Petersburg, Russia.
authors.forename: Svetlana
authors.initials: S
authors.lastname: Smirnova
mesh_terms: D017377:Diatoms / Q000502:physiology*; D017753:Ecosystem; D004784:Environmental Monitoring / Q000379:methods*; D005618:Fresh Water / Q000737:chemistry*; D019216:Metals, Heavy / Q000032:analysis* / Q000633:toxicity; D014874:Water Pollutants, Chemical / Q000032:analysis* / Q000633:toxicity
chemical_list: D019216:Metals, Heavy; D014874:Water Pollutants, Chemical
keywords: Antimony; Bioassessment; Copper; Diatoms; Zinc; “Cymbelliclinum”-like teratologies (CLT)