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Phytoremediative urban design: Transforming a derelict and polluted harbour area into a green and productive neighbourhood Texto completo
2013
Wilschut, M. | Theuws, P.A.W. | Duchhart, I.
Many urban areas are polluted by industrial activities and waste disposal in landfills. Since conventional soil remediation techniques are costly and unsustainable, phytoremediation might offer an alternative. In this article, we explore how phytoremediation can be integrated into the transformation of urban post-industrial areas, while improving public space. Buiksloterham, a polluted and deprived industrial area in Amsterdam, serves as case study. Buiksloterham is polluted with heavy metals, with Zinc (Zn) concentrations being the highest. A regression-model for Alpine Pennycress (Thlaspi caerulescens) is used to estimate the time needed to remediate the site. This reveals a conflict in time between remediation and urban development. A research by design experiment shows how to overcome this conflict by dealing with polluted soil innovatively while emphasizing spatial and aesthetic qualities of the phytoremediation plant species. The resulting landscape framework integrates phytoremediation with biomass production and gives new ecological, economic and social value to Buiksloterham.
Mostrar más [+] Menos [-]Spatial distribution assessment of particulate matter in an urban street canyon using biomagnetic leaf monitoring of tree crown deposited particles Texto completo
2013
Hofman, Jelle | Stokkaer, Ines | Snauwaert, Lies | Samson, Roeland
Recently, biomagnetic monitoring of tree leaves has proven to be a good estimator for ambient particulate concentration. This paper investigates the usefulness of biomagnetic leaf monitoring of crown deposited particles to assess the spatial PM distribution inside individual tree crowns and an urban street canyon in Ghent (Belgium). Results demonstrate that biomagnetic monitoring can be used to assess spatial PM variations, even within single tree crowns. SIRM values decrease exponentially with height and azimuthal effects are obtained for wind exposed sides of the street canyon. Edge and canyon trees seem to be exposed differently. As far as we know, this study is the first to present biomagnetic monitoring results of different trees within a single street canyon. The results not only give valuable insights into the spatial distribution of particulate matter inside tree crowns and a street canyon, but also offer a great potential as validation tool for air quality modelling.
Mostrar más [+] Menos [-]Artifact weathering, anthropogenic microparticles and lead contamination in urban soils at former demolition sites, Detroit, Michigan Texto completo
2013
Howard, Jeffrey L. | Dubay, Brian R. | Daniels, W Lee
A chronological sequence of urban soils 3–92 years old was studied to determine the effects of time on morphogenesis, artifact weathering, and the geochemical partitioning of Pb. Key chronofunctions determined are an increase in ˆA horizon Development Index (defined herein based on soil color) and water-soluble Pb, and a decrease in pH and C/N, with increasing soil age. Key artifact weathering reactions are: 1) portlandite in mortar altered to calcite, 2) ferrite in wrought-iron altered to ferrihydrite and goethite, and 3) carbonaceous materials altered to water-soluble organic substances. Mortar and wrought-iron were found to be Pb-bearing, but weather to produce immobilizing agents. Hence, they are both a source and a sink for Pb. The origin and mobilization of water-soluble Pb is complex and probably includes microbial extracellular polymeric substances, biodegraded soil organic matter, and solubilized organic substances derived from carbonaceous anthropogenic microparticles (soot, char and coal-related wastes).
Mostrar más [+] Menos [-]Effects of elevated O3 exposure on nutrient elements and quality of winter wheat and rice grain in Yangtze River Delta, China Texto completo
2013
Zheng, Feixiang | Wang, Xiaoke | Zhang, Weiwei | Hou, Peiqiang | Lu, Fei | Du, Keming | Sun, Zhongfu
With the open-top chambers (OTCs) in situ in Yangtze River Delta, China in 2007 and 2008, the effects of elevated O3 exposure on nutrient elements and quality of winter wheat and rice grain were investigated. Grain yield per plant of winter wheat and rice declined in both years. The N and S concentrations increased under elevated O3 exposure in both years and C–N ratios decreased significantly. The concentrations of K, Ca, Mg, P, Mn, Cu and Zn in winter wheat and the concentrations of Mg, K, Mn and Cu in rice increased. The concentrations of protein, amino acid and lysine in winter wheat and rice increased and the concentration of amylose decreased. The increase in the nutrient concentration was less than the reduction of grain yield in both winter wheat and rice, and, hence, the absolute amount of the nutrients was reduced by elevated O3.
Mostrar más [+] Menos [-]Occurrence and distribution of pharmaceutically active and endocrine disrupting compounds in Singapore's marine environment: Influence of hydrodynamics and physical–chemical properties Texto completo
2013
The fate and exposure risks of pharmaceutically active compounds (PhACs) and endocrine disrupting chemicals (EDCs) in marine environments are not well-understood. In this study we developed a multi-residue analytical method for quantifying concentrations of forty target compounds in seawater from Singapore. Analyses of samples (n = 24) from eight sites showed the occurrence of several compounds, including gemfibrozil (<0.09–19.8 ng/L), triclosan (<0.55–10.5 ng/L), carbamazepine (<0.28–10.9 ng/L) and ibuprofen (<2.2–9.1 ng/L). A 3D hydrodynamic model for Singapore was used to predict residence time (tR). Principal Components Analysis revealed a strong relationship between tR and contaminant concentrations. While source emissions are undoubtedly important, proximate distance to a wastewater treatment plant had little influence on concentrations. The site with the greatest tR, which exhibited the highest concentrations, is adjacent to Singapore's largest protected wetland reserve. The results highlight an important linkage between hydrodynamic behavior and contaminant exposure risks in complex coastal marine ecosystems.
Mostrar más [+] Menos [-]Phytoremediation of hexachlorocyclohexane (HCH)-contaminated soils using Cytisus striatus and bacterial inoculants in soils with distinct organic matter content Texto completo
2013
Becerra-Castro, Cristina | Kidd, Petra S. | Rodríguez-Garrido, Beatriz | Monterroso, Carmela | Santos-Ucha, Paula | Prieto-Fernández, Ángeles
The performance of Cytisus striatus in association with different microbial inoculant treatments on the dissipation of the insecticide hexachlorocyclohexane (HCH) was studied. Two soils with different organic matter (A and B soil) content were spiked with 0 or 65 mg HCH kg−1. Plants were either not inoculated (NI), or inoculated with the endophyte Rhodococcus erythropolis ET54b and the HCH-degrader Sphingomonas sp. D4 separately or in combination (ET, D4 and ETD4). Unplanted pots were also established. HCH phytotoxicity was more pronounced in the B soil. Soil HCH concentrations in unplanted pots were similar to initial concentrations, whereas concentrations were reduced after plant growth: by 20% and 8% in A and B soil, respectively. Microbial inoculants also modified HCH dissipation, although effects were soil-dependent. Inoculation with the combination of strains (ETD4) led to a significant enhancement in HCH dissipation: up to 53% in the A soil and 43% in the B soil.
Mostrar más [+] Menos [-]In-situ assessment of metal contamination via portable X-ray fluorescence spectroscopy: Zlatna, Romania Texto completo
2013
Zlatna, Romania is the site of longtime mining/smelting operations which have resulted in widespread metal pollution of the entire area. Previous studies have documented the contamination using traditional methods involving soil sample collection, digestion, and quantification via inductively coupled plasma atomic emission spectroscopy or atomic absorption. However, field portable X-ray fluorescence spectroscopy (PXRF) can accurately quantify contamination in-situ, in seconds. A PXRF spectrometer was used to scan 69 soil samples in Zlatna across multiple land use types. Each site was georeferenced with data inputted into a geographic information system for high resolution spatial interpolations. These models were laid over contemporary aerial imagery to evaluate the extent of pollution on an individual elemental basis. Pb, As, Co, Cu, and Cd exceeded governmental action limits in >50% of the sites scanned. The use of georeferenced PXRF data offers a powerful new tool for in-situ assessment of contaminated soils.
Mostrar más [+] Menos [-]Communiquer le changement climatique: un voyage dans les stratégies et plans d'adaption
2013
Stoverinck, F. | Dubois, G. | Amelung, B.
Les stratégies d’adaptation au changement climatique devraient normalement s’appuyer sur la meilleure information climatique disponible. Or le constat scientifique initial est souvent transformé, interprété, mis en forme par le processus de politique publique. Le message original s’en trouve modifié, et la qualité de sa communication initiale peut d’ailleurs elle-même être discutée. La nature et les effets de ce processus de transmission sur la prise de décision sont encore peu connus. Cet article analyse un ensemble de vingt-cinq initiatives d’adaptation au changement climatique collectées en Europe et en Méditerranée. Il étudie à la fois le type de communication visuelle déployé par les scientifiques, et ces transformations du message dans le processus de prise de décision. Les résultats montrent une sous représentation des informations sur l’incertitude liée aux projections climatiques et aux analyses d’impact (études ne s’appuyant que sur un scénario ou oubliant la dispersion des résultats). Ils montrent également une fréquente inadéquation entre les objectifs recherchés et le choix des méthodes de visualisation. Ceci entraîne une réflexion sur le besoin d’une meilleure formation à la communication des climatologues, et d’une sensibilisation au climat des décideurs, et rappelle le besoin de stratégies d’adaptation prudentes et robustes.
Mostrar más [+] Menos [-]Risk assessment of herbicides and booster biocides along estuarine continuums in the Bay of Vilaine area (Brittany, France) Texto completo
2013
Caquet, Thierry | Roucaute, Marc | Mazzella, Nicolas | Delmas, François | Madigou, C. | Farcy, E. | Burgeot, Th. | Allenou, J. -P. | Gabellec, R. | Écologie et santé des écosystèmes (ESE) ; Institut National de la Recherche Agronomique (INRA)-AGROCAMPUS OUEST | Réseaux épuration et qualité des eaux (UR REBX) ; Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA) | Unité Biogéochimie et Ecotoxicologie (BE) ; Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER) | Laboratoire Environnement Ressources Morbihan Pays de Loire (LERMPL) ; Unité Observation et écologie de la restauration des écosystèmes littoraux (COAST) ; Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER) | French National Research Agency in the framework of the program Ecotoxicology and Ecodynamics of Contaminants (ECODYN)
Risk assessment of herbicides and booster biocides along estuarine continuums in the Bay of Vilaine area (Brittany, France) Texto completo
2013
Caquet, Thierry | Roucaute, Marc | Mazzella, Nicolas | Delmas, François | Madigou, C. | Farcy, E. | Burgeot, Th. | Allenou, J. -P. | Gabellec, R. | Écologie et santé des écosystèmes (ESE) ; Institut National de la Recherche Agronomique (INRA)-AGROCAMPUS OUEST | Réseaux épuration et qualité des eaux (UR REBX) ; Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA) | Unité Biogéochimie et Ecotoxicologie (BE) ; Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER) | Laboratoire Environnement Ressources Morbihan Pays de Loire (LERMPL) ; Unité Observation et écologie de la restauration des écosystèmes littoraux (COAST) ; Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER) | French National Research Agency in the framework of the program Ecotoxicology and Ecodynamics of Contaminants (ECODYN)
A 2-year study was implemented to characterize the contamination of estuarine continuums in the Bay of Vilaine area (NW Atlantic Coast, Southern Brittany, France) by 30 pesticide and biocide active substances and metabolites. Among these, 11 triazines (ametryn, atrazine, desethylatrazine, desethylterbuthylazine, desisopropyl atrazine, Irgarol 1051, prometryn, propazine, simazine, terbuthylazine, and terbutryn), 10 phenylureas (chlortoluron, diuron, 1-(3,4-dichlorophenyl)-3-methylurea, fenuron, isoproturon, 1-(4-isopropylphenyl)-3-methylurea, 1-(4-isopropylphenyl)-urea, linuron, metoxuron, and monuron), and 4 chloroacetanilides (acetochlor, alachlor, metolachlor, and metazachlor) were detected at least once. The objectives were to assess the corresponding risk for aquatic primary producers and to provide exposure information for connected studies on the responses of biological parameters in invertebrate sentinel species. The risk associated with contaminants was assessed using risk quotients based on the comparison of measured concentrations with original species sensitivity distribution-derived hazardous concentration values. For EU Water Framework Directive priority substances, results of monitoring were also compared with regulatory Environmental Quality Standards. The highest residue concentrations and risks for primary producers were recorded for diuron and Irgarol 1051 in Arzal reservoir, close to a marina. Diuron was present during almost the all survey periods, whereas Irgarol 1051 exhibited a clear seasonal pattern, with highest concentrations recorded in June and July. These results suggest that the use of antifouling biocides is responsible for a major part of the contamination of the lower part of the Vilaine River course for Irgarol 1051. For diuron, agricultural sources may also be involved. The presence of isoproturon and chloroacetanilide herbicides on some dates indicated a significant contribution of the use of plant protection products in agriculture to the contamination of Vilaine River. Concentration levels and associated risk were always lower in estuarine sites than in the reservoir, suggesting that Arzal dam reduces downstream transfer of contaminants and favors their degradation in the freshwater part of the estuary. Results of the additional monitoring of two tidal streams located downstream of Arzal dam suggested that, although some compounds may be transferred to the estuary, their impact was probably very low. Dilution by marine water associated with tidal current was also a major factor of concentration reduction. It is concluded that the highest risks associated to herbicides and booster biocides concerned the freshwater part of the estuary and that its brackish/saltwater part was exposed to a moderate risk, although some substances may sometimes exhibit high concentration but mainly at low tide and on an irregular basis.
Mostrar más [+] Menos [-]Risk assessment of herbicides and booster biocides along estuarine continuums in the Bay of Vilaine area (Brittany, France) Texto completo
2013
Caquet, Th. | Roucaute, M. | Mazzella, N. | Delmas, F. | Madigou, C. | Farcy, E. | Burgeot, Thierry | Allenou, Jean-pierre | Gabellec, Raoul
A 2-year study was implemented to characterize the contamination of estuarine continuums in the Bay of Vilaine area (NW Atlantic Coast, Southern Brittany, France) by 30 pesticide and biocide active substances and metabolites. Among these, 11 triazines (ametryn, atrazine, desethylatrazine, desethylterbuthylazine, desisopropyl atrazine, Irgarol 1051, prometryn, propazine, simazine, terbuthylazine, and terbutryn), 10 phenylureas (chlortoluron, diuron, 1-(3,4-dichlorophenyl)-3-methylurea, fenuron, isoproturon, 1-(4-isopropylphenyl)-3-methylurea, 1-(4-isopropylphenyl)-urea, linuron, metoxuron, and monuron), and 4 chloroacetanilides (acetochlor, alachlor, metolachlor, and metazachlor) were detected at least once. The objectives were to assess the corresponding risk for aquatic primary producers and to provide exposure information for connected studies on the responses of biological parameters in invertebrate sentinel species. The risk associated with contaminants was assessed using risk quotients based on the comparison of measured concentrations with original species sensitivity distribution-derived hazardous concentration values. For EU Water Framework Directive priority substances, results of monitoring were also compared with regulatory Environmental Quality Standards. The highest residue concentrations and risks for primary producers were recorded for diuron and Irgarol 1051 in Arzal reservoir, close to a marina. Diuron was present during almost the all survey periods, whereas Irgarol 1051 exhibited a clear seasonal pattern, with highest concentrations recorded in June and July. These results suggest that the use of antifouling biocides is responsible for a major part of the contamination of the lower part of the Vilaine River course for Irgarol 1051. For diuron, agricultural sources may also be involved. The presence of isoproturon and chloroacetanilide herbicides on some dates indicated a significant contribution of the use of plant protection products in agriculture to the contamination of Vilaine River. Concentration levels and associated risk were always lower in estuarine sites than in the reservoir, suggesting that Arzal dam reduces downstream transfer of contaminants and favors their degradation in the freshwater part of the estuary. Results of the additional monitoring of two tidal streams located downstream of Arzal dam suggested that, although some compounds may be transferred to the estuary, their impact was probably very low. Dilution by marine water associated with tidal current was also a major factor of concentration reduction. It is concluded that the highest risks associated to herbicides and booster biocides concerned the freshwater part of the estuary and that its brackish/saltwater part was exposed to a moderate risk, although some substances may sometimes exhibit high concentration but mainly at low tide and on an irregular basis.
Mostrar más [+] Menos [-]Risk assessment of herbicides and booster biocides along estuarine continuums in the Bay of Vilaine area (Brittany, France) | L'évaluation du risque écotoxique d'herbicides et de biocides le long du continuum de l'estuaire de la baie de Vilaine (Bretagne, France) Texto completo
2013
Caquet, Thierry | Roucaute, Marc | Mazzella, Nicolas | Delmas, François | Madigou, Céline | Farcy, E. | Burgeot, Thierry | Allenou, J.P. | Gabellec, R. | Institut National de la Recherche Agronomique (INRA) | Réseaux épuration et qualité des eaux (UR REBX) ; Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA) | Hydrosystèmes et Bioprocédés (UR HBAN) ; Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA) | Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)
[Departement_IRSTEA]Eaux [TR1_IRSTEA]BELCA | International audience | Estuarine areas represent complex and highly changing environments at the interface between freshwater and marine aquatic ecosystems. Therefore, the aquatic organisms living in estuaries have to face highly variable environmental conditions. The aimof this work was to study the influence of environmental changes from either natural or anthropogenic origins on the physiological responses of Mytilus edulis. Mussels were collected in theVilaine estuary during early summer because this season represents a critical period of active reproduction in mussels and of increased anthropogenic inputs from agricultural and boating activities into the estuary. The physiological status of the mussel M. edulis was evaluated through measurements of a suite of biomarkers related to: oxidative stress (catalase, malondialdehyde), detoxication (benzopyrene hydroxylase, carboxylesterase), neurotoxicity (acetylcholinesterase), reproductive cycle (vitelline, condition index, maturation stages), immunotoxicity (hemocyte concentration, granulocyte percentage, phagocytosis, reactive oxygen species production, oxidative burst), and general physiological stress (lysosomal stability). A selection of relevant organic contaminant (pesticides, (polycyclic aromatic hydrocarbons, polychlorobiphenyls) was measured as well as environmental parameters (water temperature, salinity, total suspended solids, turbidity, chlorophyll a, pheopigments) and mussel phycotoxin contamination. Two locations differently exposed to the plume of the Vilaine River were compared. Both temporal and inter-site variations of these biomarkers were studied. Our results show that reproduction cycle and environmental parameters such as temperature, organic ontaminants, and algal blooms could strongly influence the biomarker responses. These observations highlight the necessity to conduct integrated environmental approaches in order to better understand the causes of biomarker variations.
Mostrar más [+] Menos [-]Effect of water quality and confounding factors on digestive enzyme activities in Gammarus fossarum Texto completo
2013
Charron, L. | Geffard, Olivier | Chaumot, Arnaud | Coulaud, Romain | Quéau, H. | Geffard, A. | Dedourge-Geffard, O. | Université de Reims Champagne-Ardenne (URCA) | Biologie des écosystèmes aquatiques (UR BELY) ; Centre national du machinisme agricole, du génie rural, des eaux et forêts (CEMAGREF) | Milieux aquatiques, écologie et pollutions (UR MALY) ; Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA) | Stress Environnementaux et BIOsurveillance des milieux aquatiques (SEBIO) ; Institut National de l'Environnement Industriel et des Risques (INERIS)-Université de Reims Champagne-Ardenne (URCA)-Université Le Havre Normandie (ULH) ; Normandie Université (NU)-Normandie Université (NU)-SFR Condorcet ; Université de Reims Champagne-Ardenne (URCA)-Centre National de la Recherche Scientifique (CNRS)-Université de Reims Champagne-Ardenne (URCA)-Centre National de la Recherche Scientifique (CNRS) | Laboratoire d'Eco-Toxicologie ; Université de Reims Champagne-Ardenne (URCA) | Unité de Recherche Interactions Animal-Environnement - EA 4689 (IAE) ; Université de Reims Champagne-Ardenne (URCA)
[Departement_IRSTEA]Eaux [TR1_IRSTEA]BELCA | International audience | The feeding activity and subsequent assimilation of the products resulting from food digestion allow organisms to obtain energy for growth, maintenance and reproduction. Among these biological parameters, we studied digestive enzymes (amylase, cellulase and trypsin) in Gammarus fossarum to assess the impact of contaminants on their access to energy resources. However, to enable objective assessment of a toxic effect of decreased water quality on an organisms’ digestive capacity, it is necessary to establish reference values based on its natural variability as a function of changing biotic and abiotic factors. To limit the confounding influence of biotic factors, a caging approach with calibrated male organisms from the same population was used. This study applied an in situ deployment at 23 sites of the Rhone basin rivers, complemented by a laboratory experiment assessing the influence of two abiotic factors (temperature and conductivity). The results showed a small effect of conductivity on cellulase activity and a significant effect of temperature on digestive enzyme activity but only at the lowest temperature (7 °C). The experimental conditions allowed us to define an environmental reference value for digestive enzyme activities to select sites where the quality of the water impacted the digestive capacity of the organisms. In addition to the feeding rate, this study showed the relevance of digestive enzymes as biomarkers to be used as an early warning tool to reflect organisms’ health and the chemical quality of aquatic ecosystems.
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