title: Silver nanoparticles uptake by salt marsh plants - Implications for phytoremediation processes and effects in microbial community dynamics.
abstract: This study investigated the uptake of silver nanoparticles (AgNPs) by a salt marsh plant, Phragmites australis, as well as AgNPs effects on rhizospheric microbial community, evaluating the implications for phytoremediation processes. Experiments were carried out with elutriate solution doped with Ag, either in ionic form or in NP form. Metal uptake was evaluated in plant tissues, elutriate solutions and sediments (by AAS) and microbial community was characterized in terms of bacterial community structure (evaluated by ARISA). Results showed Ag accumulation but only in plant belowground tissues and only in the absence of rhizosediment, the presence of sediment reducing Ag availability. But in plant roots Ag accumulation was higher when Ag was in NP form. Multivariate analysis of ARISA profiles showed significant effect of the absence/presence of Ag either in ionic or NP form on microbial community structure, although without significant differences among bacterial richness and diversity. Overall, P. australis can be useful for phytoremediation of medium contaminated with Ag, including with AgNPs. However, the presence of Ag in either forms affected the microbial community structure, which may cause disturbances in ecosystems function and compromise phytoremediation processes. Such considerations need to be address regarding environmental management strategies applied to the very important estuarine areas.
  The form in which the metal was added affected metal uptake by Phragmites australis and rhizosediment microbial community structure, which can affect phytoremediation.
authors.affiliation: CIMAR/CIIMAR - Centro Interdisciplinar de Investigação Marinha e Ambiental, Universidade do Porto, Terminal de Cruzeiros do Porto de Leixões, Av. General Norton de Matos s/n, 4450-208 Matosinhos, Portugal.
authors.forename: Joana P
authors.initials: JP
authors.lastname: Fernandes
authors.affiliation: CIMAR/CIIMAR - Centro Interdisciplinar de Investigação Marinha e Ambiental, Universidade do Porto, Terminal de Cruzeiros do Porto de Leixões, Av. General Norton de Matos s/n, 4450-208 Matosinhos, Portugal.
authors.forename: Ana P
authors.initials: AP
authors.lastname: Mucha
authors.affiliation: Faculdade de Ciências, Universidade do Porto, Rua do Campo Alegre, s/n, 4169-007 Porto, Portugal.
authors.forename: Telmo
authors.initials: T
authors.lastname: Francisco
authors.affiliation: CIMAR/CIIMAR - Centro Interdisciplinar de Investigação Marinha e Ambiental, Universidade do Porto, Terminal de Cruzeiros do Porto de Leixões, Av. General Norton de Matos s/n, 4450-208 Matosinhos, Portugal; Faculdade de Ciências, Universidade do Porto, Rua do Campo Alegre, s/n, 4169-007 Porto, Portugal.
authors.forename: Carlos Rocha
authors.initials: CR
authors.lastname: Gomes
authors.affiliation: CIMAR/CIIMAR - Centro Interdisciplinar de Investigação Marinha e Ambiental, Universidade do Porto, Terminal de Cruzeiros do Porto de Leixões, Av. General Norton de Matos s/n, 4450-208 Matosinhos, Portugal. Electronic address: calmeida@ciimar.up.pt.
authors.forename: C Marisa R
authors.initials: CMR
authors.lastname: Almeida
mesh_terms: D001673:Biodegradation, Environmental; D053768:Metal Nanoparticles; D053758:Nanoparticles; D018517:Plant Roots / Q000737:chemistry; D006109:Poaceae; D012834:Silver / Q000493:pharmacokinetics; D053833:Wetlands
chemical_list: D012834:Silver
keywords: Bacterial community structure; Phytoremediation; Remediation of ecosystems; Silver; Silver nanoparticles