title: Experimental assessment of the water quality influence on the phosphorus uptake of an invasive aquatic plant: biological responses throughout its phenological stage.
abstract: Understanding how an invasive plant can colonize a large range of environments is still a great challenge in freshwater ecology. For the first time, we assessed the relative importance of four factors on the phosphorus uptake and growth of an invasive macrophyte Elodea nuttallii (Planch.) St. John. This study provided data on its phenotypic plasticity, which is frequently suggested as an important mechanism but remains poorly investigated. The phosphorus uptake of two Elodea nuttallii subpopulations was experimentally studied under contrasting environmental conditions. Plants were sampled in the Rhine floodplain and in the Northern Vosges mountains, and then maintained in aquaria in hard (Rhine) or soft (Vosges) water. Under these conditions, we tested the influence of two trophic states (eutrophic state, 100 μg x l(-1) P-PO4(3-) and hypertrophic state, 300 μg x l(-1) P-PO4(3-)) on the P metabolism of plant subpopulations collected at three seasons (winter, spring and summer). Elodea nuttallii was able to absorb high levels of phosphorus through its shoots and enhance its phosphorus uptake, continually, after an increase of the resource availability (hypertrophic > eutrophic). The lowest efficiency in nutrient use was observed in winter, whereas the highest was recorded in spring, what revealed thus a storage strategy which can be beneficial to new shoots. This experiment provided evidence that generally, the water trophic state is the main factor governing P uptake, and the mineral status (softwater > hardwater) of the stream water is the second main factor. The phenological stage appeared to be a confounding factor to P level in water. Nonetheless, phenology played a role in P turnover in the plant. Finally, phenotypic plasticity allows both subpopulations to adapt to a changing environment.
authors.affiliation: Laboratoire d'Hydrologie et de Géochimie de Strasbourg (LHyGeS UMR 7517 UdS / CNRS), Institut de Botanique, 28 rue Goethe, F-67083, Strasbourg Cedex, France; Aix Marseille Université, CNRS, IRD, Avignon Université, Institut Méditerranéen de Biodiversité et d'Ecologie IMBE UMR 7263, CS 80249, 13331, Marseille, Cedex 03, France.
authors.forename: Virginie
authors.initials: V
authors.lastname: Baldy
authors.affiliation: Laboratoire Ecosystèmes-Biodiversité-Evolution-ECOBIO-UMR CNRS 6553, 263 av. Général Leclerc, F-35042, Rennes Cedex, France.
authors.forename: Gabrielle
authors.initials: G
authors.lastname: Thiebaut
authors.affiliation: Aix Marseille Université, CNRS, IRD, Avignon Université, Institut Méditerranéen de Biodiversité et d'Ecologie IMBE UMR 7263, CS 80249, 13331, Marseille, Cedex 03, France.
authors.forename: Catherine
authors.initials: C
authors.lastname: Fernandez
authors.affiliation: Epidemiology and ecology of microorganisms, Crop Research Institute, Prague, Czech Republic.
authors.forename: Marketa
authors.initials: M
authors.lastname: Sagova-Mareckova
authors.affiliation: Aix Marseille Université, CNRS, IRD, Avignon Université, Institut Méditerranéen de Biodiversité et d'Ecologie IMBE UMR 7263, CS 80249, 13331, Marseille, Cedex 03, France; Irstea, UR EFNO, centre de Nogent-sur-Vernisson, F-45290, Nogent-sur-Vernisson, France.
authors.forename: Nathalie
authors.initials: N
authors.lastname: Korboulewsky
authors.affiliation: Aix Marseille Université, CNRS, IRD, Avignon Université, Institut Méditerranéen de Biodiversité et d'Ecologie IMBE UMR 7263, CS 80249, 13331, Marseille, Cedex 03, France; INRA, UMR AMAP, Montpellier, F-34000, France.
authors.forename: Yogan
authors.initials: Y
authors.lastname: Monnier
authors.affiliation: Aix Marseille Université, CNRS, IRD, Avignon Université, Institut Méditerranéen de Biodiversité et d'Ecologie IMBE UMR 7263, CS 80249, 13331, Marseille, Cedex 03, France.
authors.forename: Thierry
authors.initials: T
authors.lastname: Perez
authors.affiliation: Laboratoire d'Hydrologie et de Géochimie de Strasbourg (LHyGeS UMR 7517 UdS / CNRS), Institut de Botanique, 28 rue Goethe, F-67083, Strasbourg Cedex, France.
authors.forename: Michele
authors.initials: M
authors.lastname: Tremolieres
mesh_terms: D001692:Biological Transport; D002118:Calcium / Q000032:analysis; D031321:Hydrocharitaceae / Q000254:growth & development / Q000378:metabolism*; D058865:Introduced Species; D007700:Kinetics; D010641:Phenotype; D010758:Phosphorus / Q000378:metabolism*; D018520:Plant Shoots / Q000254:growth & development / Q000378:metabolism; D014867:Water / Q000737:chemistry; D060753:Water Quality
chemical_list: D014867:Water; D010758:Phosphorus; D002118:Calcium