title: Impact of a wastewater treatment plant on microbial community composition and function in a hyporheic zone of a eutrophic river.
abstract: The impact of the installation of a technologically advanced wastewater treatment plant (WWTP) on the benthic microbial community of a vinyl chloride (VC) impacted eutrophic river was examined two years before, and three and four years after installation of the WWTP. Reduced dissolved organic carbon and increased dissolved oxygen concentrations in surface water and reduced total organic carbon and total nitrogen content in the sediment were recorded in the post-WWTP samples. Pyrosequencing of bacterial 16S rRNA gene fragments in sediment cores showed reduced relative abundance of heterotrophs and fermenters such as Chloroflexi and Firmicutes in more oxic and nutrient poor post-WWTP sediments. Similarly, quantitative PCR analysis showed 1-3 orders of magnitude reduction in phylogenetic and functional genes of sulphate reducers, denitrifiers, ammonium oxidizers, methanogens and VC-respiring Dehalococcoides mccartyi. In contrast, members of Proteobacteria adapted to nutrient-poor conditions were enriched in post-WWTP samples. This transition in the trophic state of the hyporheic sediments reduced but did not abolish the VC respiration potential in the post-WWTP sediments as an important hyporheic sediment function. Our results highlight effective nutrient load reduction and parallel microbial ecological state restoration of a human-stressed urban river as a result of installation of a WWTP.
authors.affiliation: Laboratory of Microbiology, Wageningen University, Dreijenplein 10, 6703 HB Wageningen, The Netherlands.|Flemish Institute for Technological Research (VITO), Separation and Conversion Technology, Boeretang 200, 2400 Mol, Belgium.|KU Leuven, Division Soil and Water Management, Kasteelpark Arenberg 20, 3001 Heverlee, Belgium.
authors.forename: Siavash
authors.initials: S
authors.lastname: Atashgahi
authors.affiliation: Laboratory of Microbiology, Wageningen University, Dreijenplein 10, 6703 HB Wageningen, The Netherlands.
authors.forename: Rozelin
authors.initials: R
authors.lastname: Aydin
authors.affiliation: Laboratory of Microbiology, Wageningen University, Dreijenplein 10, 6703 HB Wageningen, The Netherlands.
authors.forename: Mauricio R
authors.initials: MR
authors.lastname: Dimitrov
authors.affiliation: Laboratory of Microbiology, Wageningen University, Dreijenplein 10, 6703 HB Wageningen, The Netherlands.
authors.forename: Detmer
authors.initials: D
authors.lastname: Sipkema
authors.affiliation: Flemish Institute for Technological Research (VITO), Separation and Conversion Technology, Boeretang 200, 2400 Mol, Belgium.
authors.forename: Kelly
authors.initials: K
authors.lastname: Hamonts
authors.affiliation: Laboratory of Microbiology, Wageningen University, Dreijenplein 10, 6703 HB Wageningen, The Netherlands.|Department of Veterinary Biosciences, University of Helsinki, PO Box 66, FI-00014, Finland.
authors.forename: Leo
authors.initials: L
authors.lastname: Lahti
authors.affiliation: Laboratory of Microbiology, Wageningen University, Dreijenplein 10, 6703 HB Wageningen, The Netherlands.
authors.forename: Farai
authors.initials: F
authors.lastname: Maphosa
authors.affiliation: Laboratory of Microbiology, Wageningen University, Dreijenplein 10, 6703 HB Wageningen, The Netherlands.
authors.forename: Thomas
authors.initials: T
authors.lastname: Kruse
authors.affiliation: Laboratory of Systems and Synthetic Biology, Wageningen University, Dreijenplein 10, 6703 HB, Wageningen, The Netherlands.
authors.forename: Edoardo
authors.initials: E
authors.lastname: Saccenti
authors.affiliation: KU Leuven, Division Soil and Water Management, Kasteelpark Arenberg 20, 3001 Heverlee, Belgium.
authors.forename: Dirk
authors.initials: D
authors.lastname: Springael
authors.affiliation: Flemish Institute for Technological Research (VITO), Separation and Conversion Technology, Boeretang 200, 2400 Mol, Belgium.
authors.forename: Winnie
authors.initials: W
authors.lastname: Dejonghe
authors.affiliation: Laboratory of Microbiology, Wageningen University, Dreijenplein 10, 6703 HB Wageningen, The Netherlands.
authors.forename: Hauke
authors.initials: H
authors.lastname: Smidt
mesh_terms: D001419:Bacteria / Q000378:metabolism*; D044822:Biodiversity; D019069:Cell Respiration / Q000187:drug effects; D005068:Eutrophication / Q000187:drug effects; D005819:Genetic Markers; D019015:Geologic Sediments / Q000382:microbiology; D054879:Halogenation / Q000187:drug effects; D010802:Phylogeny; D045483:Rivers / Q000382:microbiology*; D014752:Vinyl Chloride / Q000633:toxicity; D062065:Wastewater / Q000382:microbiology*; D018508:Water Purification / Q000379:methods*
chemical_list: D005819:Genetic Markers; D014752:Vinyl Chloride; D062065:Wastewater