title: Assessment of PAH dissipation processes in large-scale outdoor mesocosms simulating vegetated road-side swales.
abstract: Biofilters have been implemented in urban areas due to their ability to improve road runoff quality. However, little is known about the role of soil microorganisms and plants on pollutant remediation in planted swales. Therefore, four large-scale outdoor mesocosms were built and co-contaminated with metals and model polycyclic aromatic hydrocarbons (PAHs) (phenanthrene (Phen), pyrene (Pyr) and benzo[a]pyrene (BaP)), to better understand the complex functioning of swale-like environments. Three macrophyte plant species were tested for enhanced remediation of PAHs: Juncus effusus, Iris pseudacorus, Phalaris arundinacea and a grass mix. Long-term dynamics of PAHs in water outflow and soil was studied. Results showed that only 0.07 to 0.22% of total PAHs were released in water outflow after one year. Two years after contamination, soil sample analyses showed a dissipation of 99.6% for Phen and 99.4% for Pyr whatever the mesocosm considered and ranging from 75.5 to 91% for BaP, depending on plant species. Furthermore, dissipation time-courses may be described by a biphasic process. Experiments showed that the grass mix facilitated BaP long-term biodegradation. Grass appeared also to be the best filter for suspended solids because of its dense rhizosphere, which prevents the transfer of BaP to groundwater.
authors: UMR CNRS 6014 COBRA, Université de Rouen, IUT d'Evreux, 55 rue Saint Germain, 27000 Evreux, France; Unité Agri'Terr, Esitpa - Ecole d'Ingénieurs en Agriculture, 3 rue du Tronquet, 76134 Mont-Saint-Aignan Cedex, France; INFRA Services, 55b rue Gaston Boulet, 76380 Canteleu, France. Electronic address: mcleroy@infraservices.fr.
authors: M C
authors: MC
authors: Leroy
authors: Unité Agri'Terr, Esitpa - Ecole d'Ingénieurs en Agriculture, 3 rue du Tronquet, 76134 Mont-Saint-Aignan Cedex, France. Electronic address: mlegras@esitpa.org.
authors: M
authors: M
authors: Legras
authors: COBRA UMR CNRS 6014, INSA de Rouen, avenue de l'Université, 76800 Saint-Etienne-du-Rouvray, France. Electronic address: stephane.marcotte@insa-rouen.fr.
authors: S
authors: S
authors: Marcotte
authors: INFRA Services, 55b rue Gaston Boulet, 76380 Canteleu, France. Electronic address: vmoncondhuy@infraservices.fr.
authors: V
authors: V
authors: Moncond'huy
authors: UMR CNRS 6014 COBRA, Université de Rouen, IUT d'Evreux, 55 rue Saint Germain, 27000 Evreux, France. Electronic address: nadine.merlet@univ-rouen.fr.
authors: N
authors: N
authors: Machour
authors: UMR CNRS 6014 COBRA, Université de Rouen, IUT d'Evreux, 55 rue Saint Germain, 27000 Evreux, France. Electronic address: franck.lederf@univ-rouen.fr.
authors: F
authors: F
authors: Le Derf
authors: UMR CNRS 6014 COBRA, Université de Rouen, IUT d'Evreux, 55 rue Saint Germain, 27000 Evreux, France. Electronic address: florence.koltalo@univ-rouen.fr.
authors: F
authors: F
authors: Portet-Koltalo
mesh_terms: D001673:Biodegradation, Environmental; D017753:Ecosystem; D004784:Environmental Monitoring; D018517:Plant Roots; D010944:Plants; D011084:Polycyclic Aromatic Hydrocarbons / Q000032:analysis*; D012987:Soil; D012988:Soil Microbiology; D012989:Soil Pollutants / Q000032:analysis*
chemical_list: D011084:Polycyclic Aromatic Hydrocarbons; D012987:Soil; D012989:Soil Pollutants
keywords: Biodegradation; Infiltration water; Mesocosms; Planted swales; Polycyclic aromatic hydrocarbons; Road runoff