title: Field application of a planted fixed bed reactor (PFR) for support media and rhizosphere investigation using undisturbed samples from full-scale constructed wetlands.
abstract: This study presents a novel method for investigations on undisturbed samples from full-scale horizontal subsurface-flow constructed wetlands (HSSFCW). The planted fixed bed reactor (PFR), developed at the Helmholtz Center for Environmental Research (UFZ), is a universal test unit for planted soil filters that reproduces the operational conditions of a constructed wetland (CW) system in laboratory scale. The present research proposes modifications on the PFR original configuration in order to allow its operation in field conditions. A mobile device to obtain undisturbed samples from real-scale HSSFCW was also developed. The experimental setting is presented with two possible operational configurations. The first allows the removal and replacement of undisturbed samples in the CW bed for laboratory investigations, guaranteeing sample integrity with a mobile device. The second allows the continuous operation of the PFR and undisturbed samples as a fraction of the support media, reproducing the same environmental conditions outside the real-scale system. Investigations on the hydrodynamics of the adapted PFR were carried out with saline tracer tests, validating the proposed adaptation. Six adapted PFR units were installed next to full-scale HSSFCW beds and fed with interstitial liquid pumped from two regions of planted and unplanted support media. Fourteen points were monitored along the system, covering carbon fractions, nitrogen and sulfate. The results indicate the method as a promising tool for investigations on CW support media, rhizosphere and open space for studies on CW modeling, respirometry, kinetic parameters, microbial communities, redox potential and plant influence on HSSFCW.
authors.affiliation: Department of Sanitary and Environmental Engineering, Federal University of Minas Gerais, Av. Antônio Carlos 6627 - Escola de Engenharia, Bloco 1 - sala 4622, Belo Horizonte 31270-901, Brazil E-mail: andrebaxterbarreto@gmail.com.
authors.forename: A B
authors.initials: AB
authors.lastname: Barreto
authors.affiliation: Department of Sanitary and Environmental Engineering, Federal University of Minas Gerais, Av. Antônio Carlos 6627 - Escola de Engenharia, Bloco 1 - sala 4622, Belo Horizonte 31270-901, Brazil E-mail: andrebaxterbarreto@gmail.com.
authors.forename: G R
authors.initials: GR
authors.lastname: Vasconcellos
authors.affiliation: Department of Sanitary and Environmental Engineering, Federal University of Minas Gerais, Av. Antônio Carlos 6627 - Escola de Engenharia, Bloco 1 - sala 4622, Belo Horizonte 31270-901, Brazil E-mail: andrebaxterbarreto@gmail.com.
authors.forename: M
authors.initials: M
authors.lastname: von Sperling
authors.affiliation: Helmholtz Center for Environmental Research (UFZ), Environmental Biotechnology UBT, Permoserstrasse, 15, Leipzig 04318, Germany.
authors.forename: P
authors.initials: P
authors.lastname: Kuschk
authors.affiliation: Helmholtz Center for Environmental Research (UFZ), Environmental Biotechnology UBT, Permoserstrasse, 15, Leipzig 04318, Germany.
authors.forename: U
authors.initials: U
authors.lastname: Kappelmeyer
authors.affiliation: Department of Science and Environmental Management, Unit Environment and Sanitation, University of Liege, Campus Arlon, Belgium.
authors.forename: J L
authors.initials: JL
authors.lastname: Vasel
mesh_terms: D019149:Bioreactors; D001938:Brazil; D004784:Environmental Monitoring / Q000379:methods*; D058441:Rhizosphere; D014874:Water Pollutants, Chemical / Q000032:analysis*; D053833:Wetlands
chemical_list: D014874:Water Pollutants, Chemical