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Beach debris on Aruba, Southern Caribbean: Attribution to local land-based and distal marine-based sources Texte intégral
2016
de Scisciolo, Tobia | Mijts, Eric N. | Becker, Tatiana | Eppinga, Maarten B.
Accumulation of marine (plastic) debris from local land-based and distal marine-based sources along coastlines is a pressing modern issue. Hitherto, assessing the relative contribution of pollution sources through beach surveys is methodologically challenging. We surveyed ten beaches along the leeward and windward coastlines of Aruba (southern Caribbean) to determine differences in macro- and meso-debris densities. Differences were quantified using three metrics: 1) the gradient in macro-debris density away from the waterfront; 2) the proportion of plastic within macro-debris; 3) the meso-:macro-debris ratio. Overall 42,585 macro-debris items and 884 meso-debris items were collected. The density of near-shore macro-debris, proportion of plastic debris herein, and meso-:macro-debris ratio were highest on the windward coastline. These results suggest that southern Caribbean windward coastlines are mainly exposed to debris originating from distal marine-based sources, and leeward coastlines to local land-based sources. Our metrics clearly reflect these differences, providing novel means to survey debris source origin.
Afficher plus [+] Moins [-]Crop protection and environmental health: legacy management and new concepts Texte intégral
2016
Devault, Damien A. | Macarie, Hervé | Lemoine, Soazig | Archéologie Industrielle, Histoire, Patrimoine - Géographie, Développement, Environnement de la Caraïbe [UR6_1] (AIHP-GEODE) ; Université des Antilles (UA) | Ecologie Systématique et Evolution (ESE) ; Université Paris-Sud - Paris 11 (UP11)-AgroParisTech-Centre National de la Recherche Scientifique (CNRS) | Institut méditerranéen de biodiversité et d'écologie marine et continentale (IMBE) ; Avignon Université (AU)-Aix Marseille Université (AMU)-Institut de recherche pour le développement [IRD] : UMR237-Centre National de la Recherche Scientifique (CNRS) | Institut de recherche pour le développement [IRD] : UMR237 | Biologie des Organismes et Ecosystèmes Aquatiques (BOREA) ; Université de Caen Normandie (UNICAEN) ; Normandie Université (NU)-Normandie Université (NU)-Muséum national d'Histoire naturelle (MNHN)-Institut de Recherche pour le Développement (IRD)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université des Antilles (UA)
International audience | This the Editorial of the special issue of the journal "Environmental Science and Pollution Research" dedicated to the annual congress of the French Group on Pesticide (GFP with its initials in French) that was held in Martinique in May 2014.
Afficher plus [+] Moins [-]Dynamics of phytoplankton communities in eutrophying tropical shrimp ponds affected by vibriosis Texte intégral
2016
Lemonnier, Hugues | Lantoine, Francois | Courties, Claude | Guillebault, Delphine | Nezan, Elisabeth | Chomerat, Nicolas | Escoubeyrou, Karine | Galinie, Christian | Blockmans, Bernard | Laugier, Thierry
Dynamics of phytoplankton communities in eutrophying tropical shrimp ponds affected by vibriosis Texte intégral
2016
Lemonnier, Hugues | Lantoine, Francois | Courties, Claude | Guillebault, Delphine | Nezan, Elisabeth | Chomerat, Nicolas | Escoubeyrou, Karine | Galinie, Christian | Blockmans, Bernard | Laugier, Thierry
Tropical shrimp aquaculture systems in New Caledonia regularly face major crises resulting from outbreaks of Vibrio infections. Ponds are highly dynamic and challenging environments and display a wide range of trophic conditions. In farms affected by vibriosis, phytoplankton biomass and composition are highly variable. These conditions may promote the development of harmful algae increasing shrimp susceptibility to bacterial infections. Phytoplankton compartment before and during mortality outbreaks was monitored at a shrimp farm that has been regularly and highly impacted by these diseases. Combining information from flow cytometry, microscopy, pigment and phylogenetic analysis, the presence of Picocyanobacteria, Prasinophyceae and Diatomophyceae were detected as dominant phytoplankton groups and Cryptophyceae, Prymnesiophyceae and Dinophyceae as minor components. At the onset of the first shrimp mortalities, Bacillariophyceae increased while Cyanobacteria, Prymnesiophyceae and Dinophyceae decreased in the water column, followed by proliferation of Prasinophyceae. Several taxa were identified as potential harmful algae (Cyanobacteria, dinoflagellates and Phaeocystis).
Afficher plus [+] Moins [-]Dynamics of phytoplankton communities in eutrophying tropical shrimp ponds affected by vibriosis Texte intégral
2016
Lemonnier, Hugues | Lantoine, François | Courties, Claude | Guillebault, Delphine | Nézan, Elizabeth | Chomérat, Nicolas | Escoubeyrou, Karine | Galinié, Christian | Blockmans, Bernard | Laugier, Thierry
Tropical shrimp aquaculture systems in New Caledonia regularly face major crises resulting from outbreaks of Vibrio infections. Ponds are highly dynamic and challenging environments and display a wide range of trophic conditions. In farms affected by vibriosis, phytoplankton biomass and composition are highly variable. These conditions may promote the development of harmful algae increasing shrimp susceptibility to bacterial infections. Phytoplankton compartment before and during mortality outbreaks was monitored at a shrimp farm that has been regularly and highly impacted by these diseases. Combining information from flow cytometry, microscopy, pigment and phylogenetic analysis, the presence of Picocyanobacteria, Prasinophyceae and Diatomophyceae were detected as dominant phytoplankton groups and Cryptophyceae, Prymnesiophyceae and Dinophyceae as minor components. At the onset of the first shrimp mortalities, Bacillariophyceae increased while Cyanobacteria, Prymnesiophyceae and Dinophyceae decreased in the water column, followed by proliferation of Prasinophyceae. Several taxa were identified as potential harmful algae (Cyanobacteria, dinoflagellates and Phaeocystis).
Afficher plus [+] Moins [-]Investigation of fungal volatile organic compounds in hospital air Texte intégral
2016
Pantoja, Lydia Dayanne Maia | do Nascimento, Ronaldo Ferreira | de Araújo Nunes, Ana Barbara
Fungal growth within the structure of buildings or in ventilation filters generates “hidden contamination”, which cannot be detected only through visual inspection. At the beginning of development, the fungi release fungal volatile organic compounds (FVOCs) into the atmosphere, which can originate from metabolic pathways or from the enzymatic degradation of materials. This study analyzed the air quality of a public referral hospital in Fortaleza, Ceará, Brazil in terms of FVOCs, to establish ways to improve methods of monitoring and control of specific sectors in the hospital. For that, we created and validated a protocol for detection of FVOCs, using GC/MS, while fungal samples were identified by analysis of macro and micromorphology. In total, 48 samples (60.5% positive) were analyzed for FVOCs; 7 were detected in at least one of the sectors analyzed, with 2-heptanone (179.5 μg/m3) and 2-methyl-1-propanol (121.5 μg/m3) as the most abundant. With respect to fungal findings, 24 samples were analyzed, with a high number of colony-forming units per cubic meter (CFU/m3) observed in all sectors. The airborne fungal spectrum revealed the existence of 19 genera, composed predominantly by hyaline filamentous deuteromycetes. Analysis with periodic monitoring is still needed to allow improvement in the data quality. Also, further discussion on the subject in the academic and legislative environment is needed to contribute to the systematic study of aerobiology.
Afficher plus [+] Moins [-]Characterization of microplastic and mesoplastic debris in sediments from Kamilo Beach and Kahuku Beach, Hawai'i Texte intégral
2016
Young, Alan M. | Elliott, James A.
Sediment samples were collected from two Hawai'ian beaches, Kahuku Beach on O'ahu and Kamilo Beach on the Big Island of Hawai'i. A total of 48,988 large microplastic and small mesoplastic (0.5–8mm) particles were handpicked from the samples and sorted into four size classes (0.5–1mm, 1–2mm, 2–4mm, 4–8mm) and nine color categories. For all sizes combined the most common plastic fragment color was white/transparent (71.8%) followed by blue (8.5%), green (7.5%), black/grey (7.3%), red/pink (2.6%), yellow (1.2%), orange (0.6%), brown (0.3%) and purple (0.2%). Color frequency distribution based on both numbers and mass of particles was not significantly different among the various size classes nor between the two beaches. White and black/grey resin pellets accounted for 11.3% of the particles collected from Kahuku Beach and 4.2% of the particles from Kamilo Beach. Plastic type based on Raman Spectrometer analysis of a small representative subsample indicated that most of the fragments were polyethylene and a few were polypropylene.
Afficher plus [+] Moins [-]Assessment of heavy metal contamination in surface sediments of the west Guangdong coastal region, China Texte intégral
2016
Zhao, Guangming | Lu, Qingyuan | Ye, Siyuan | Yuan, Hongming | Ding, Xigui | Wang, Jin
Heavy metals (As, Cd, Cr, Cu, Hg, Pb, Zn), organic carbon and grain size of 237 surface sediment samples and one sediment core, taken from the west Guangdong coastal region in January 2008, were analyzed to evaluate the spatial distribution and pollution status. Results show that the ranges of the measured heavy metal concentrations in sediments are as follows: 8.33–39.49mg/kg for As, 0.1–1.49mg/kg for Cd, 33–108mg/kg for Cr, 11.5–78.8mg/kg for Cu, 0.04–0.26mg/kg for Hg, 21–73mg/kg for Pb, 56–248mg/kg for Zn. The heavy metal enrichment is closely associated with Corg and grain size. Both the metal enrichment factor and geoaccumulation index indicate that there was no detected pollution on metals As, Cr, Cu, Pb in our study area and a slight to moderate contamination of Cd, Hg and Zn. However, As, Cr and Cu have showed a certain risk.
Afficher plus [+] Moins [-]Hydrodynamic properties of San Quintin Bay, Baja California: Merging models and observations Texte intégral
2016
Melaku Canu, Donata | Aveytua-Alcázar, Leslie | Camacho-Ibar, Victor F. | Querin, Stefano | Solidoro, Cosimo
We investigated the physical dynamics of San Quintin Bay, a coastal lagoon located on the Pacific coast of northern Baja California, Mexico. We implemented, validated and used a finite element 2-D hydrodynamic model to characterize the spatial and temporal variability of the hydrodynamic of the bay in response to variability in the tidal regime and in meteorological forcing patterns. Our analysis of general circulation, residual currents, residence times, and tidal propagation delays allowed us to characterize spatial variability in the hydrodynamic basin features. The eulerian water residence time is –on average and under reference conditions– approximately 7days, although this can change significantly by region and season and under different tidal and meteorological conditions. Ocean upwelling events that bring colder waters into the bay mouth affect hydrodynamic properties in all areas of the lagoon and may affect ecological dynamics. A return to pre-upwelling conditions would take approximately 10days.
Afficher plus [+] Moins [-]Effect and mechanism of a High Gradient Magnetic Separation (HGMS) and Ultraviolet (UV) composite process on the inactivation of microbes in ballast water Texte intégral
2016
Ren, Zhijun | Zhang, Lin | Shi, Yue | Leng, Xiaodong | Shao, Jingchao
The patented technology of a High Gradient Magnetic Separation (HGMS)-Ultraviolet (UV) composite process was used to treat ballast water. Staphylococcus aureus (S. aureus) was selected as the reference bacteria. After treatment by the HGMS-UV process, the concentration of S. aureus on the log 10 scale was lower than 2 at different flow rates, S. aureus suffered the most serious damage, and K+ leakage of the bacteria was 1.73mg/L higher than separate 60min UV irradiation (1.17mg/L) and HGMS (0.12mg/L) processes. These results demonstrated that the HGMS-UV composite process was an effective approach to treat ballast water. Further, the HGMS process had synergistic action on the subsequent UV irradiation process and accelerated cell membrane damage. Meanwhile, the results of superoxide dismutase (SOD) activities of bacteria and DNA band analyses indicated that the inactivation mechanisms were different for HGMS and UV irradiation.
Afficher plus [+] Moins [-]Mercury concentration in fine atmospheric particles during haze and non-haze days in Shanghai, China Texte intégral
2016
Bo, Dandan | Cheng Jinping, | Xie, Haiyun | Zhao, Wenchang | Wei, Yuqing | Chen, Xiaojia
Concentrations of fine particulate mercury (PHg), particulate matter ≤2.5 μm (PM2.5), and particulate matter ≤10 μm (PM10) were monitored for the whole year of 2013 in Shanghai, China. The average concentrations of PHg were 1270 ± 716 pg/m3 and 341 ± 187 pg/m3 during haze and non-haze days respectively. The average PHg concentration throughout the whole year 2013 was 642 ± 616pg/m3. It was observed that PHg concentrations on haze days were 3 times higher than on non-haze days. The concentration of PHg on non-haze days in 2013 varied from 0.25 to 0.48 ng/m3. The mean monthly PHg concentration was highest in December (1.92 ng/m3), while the minimum mean concentration was observed in February and August (0.80 ng/m3), and there was a clear seasonal variation: winter (1.67 ng/m3), autumn (1.08 ng/m3), spring (1.02 ng/m3), and summer (1.00 ng/m3) during haze days. The correlation between PHg and PM2.5 was strong (r = 0.96 on haze days; r = 0.90 on non-haze days), while the correlation between PHg and PM10 was weaker (r = 0.85 on haze days; r = 0.57 on non-haze days). The PHg concentration on haze days was always higher than on non-haze days, indicating that haze conditions were accelerating the formation of PHg. The result also indicated that PHg was inclined to combine with fine particles. The existence of strong correlations between the concentrations of PM2.5, PM10, and PHg indicated the commonality of the contributing sources, such as traffic, industrial emissions, and the combustion of coal.
Afficher plus [+] Moins [-]SPECIEUROPE: The European data base for PM source profiles Texte intégral
2016
Pernigotti, Denise | Belis, Claudio A. | Spanò, Luca
A new database of atmospheric particulate matter emission source profiles in Europe (SPECIEUROPE) developed in the framework of the Forum for air quality modeling in Europe (FAIRMODE, Working Group 3) is accessible at the website http://source-apportionment.jrc.ec.europa.eu/Specieurope/index.aspx. It contains the chemical composition of particulate matter emission sources reported in the scientific literature and reports drafted by competent authorities. The first release of SPECIEUROPE consists of 151 measured (original), 13 composite (merging different subcategories of similar sources), 6 calculated (from stoichiometric composition) and 39 derived (results of source apportionment studies) profiles. Each profile is related to one or more source categories or subcategories. The sources with the highest PM relative mass toxic pollutants such as PAHs are fuel oil burning, ship emissions, coke burning and wood burning. Heavy metals are most abundant in metal processing activities while halogens are mostly present in fertilizer production, coal burning and metallurgic sector. Anhydrosugars are only measured in biomass and wood burning source categories, because are markers for these categories. The alkaline earth metals are mostly present in road dust, cement production, soil dust and sometimes coal burning. Source categories like traffic and industrial, which contain heterogeneous subcategories, show the greatest internal variability.The relationships between sources profiles were also explored using a cluster analysis approach based upon the Standardized Identity Distance (SID) indicator. The majority of profiles are allocated in 8 major clusters. Some of the clusters include profiles mainly from one source category (e.g. wood burning) while others, such as industrial source profiles, are more heterogeneous and spread over three different clusters.
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