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Impact of cigarette butt leachate on tidepool snails
2015
Booth, David J. | Gribben, Paul | Parkinson, Kerryn
In urban areas, cigarette butts are the most common discarded refuse articles. In marine intertidal zones, they often fall into tidepools. We tested how common intertidal molluscs were affected by butt leachate in a laboratory experiment, where snails were exposed to various leachate concentrations. Mortality was very high, with all species showing 100% mortality at the full leachate concentration (5 butts per litre and 2h soak time) after 8days. However, Austrocochlea porcata showed higher mortality than the other 2 species at lower concentrations (10%, 25%) which may affect the relative abundance of the 3 snails under different concentrations of leachate pollution. Also, sublethal effects of leachate on snail activity were observed, with greater activity of Nerita atramentosa than the other 2 species at higher concentrations, suggesting it is more resilient than the other 2 species.While human health concerns predominate with respect to smoking, we show strong lethal and sublethal (via behavioural modifications) impacts of discarded butts on intertidal organisms, with even closely-related taxa responding differently.
Afficher plus [+] Moins [-]Ranking the suitability of common urban tree species for controlling PM2.5 pollution
2015
Yang, Jun | Chang, Yamin | Yan, Pengbo
Pollution caused by particles with aerodynamic diameters less than 2.5μm (PM2.5) is now a major environmental problem in many Asian cities. Planting more trees has been suggested as an unconventional approach to alleviate the problem. In this study, we developed a ranking approach to evaluate the PM2.5 removal efficiency, negative impacts on air quality, and the suitability to urban environments of commonly occurring urban tree species. The results showed that the most frequently occurring tree species in global cities were not the best performers in removing PM2.5. Among the ten most frequently occurring tree species, only London plane (Platanus acerifolia (Aiton) Wild.), silver maple (Acer saccharinum L.) and honey locust (Gleditsia triacanthos L.) were ranked above average. However, there is great potential for improving the removal of PM2.5 from urban air by using species that have high PM2.5 removal efficiency, especially conifer species. Use of conifer species requires choosing the correct gender and matching trees with appropriate sites. The results from this study can assist environmental management agencies in the selection of tree species for urban greening projects focusing on PM2.5 control.
Afficher plus [+] Moins [-]Urban air quality management-A review
2015
Gulia, Sunil | Shiva Nagendra, S.M. | Khare, Mukesh | Khanna, Isha
Urban air quality management plan (UAQMP) is an effective and efficient tool employed in managing acceptable urban air quality. However, the UAQM practices are specific to a country’s needs and requirements. Majority of the developed countries have full–fledged UAQMP with a regulatory management framework. However, developing countries are still working in formulating the effective and efficient UAQMPs to manage their deteriorating urban air environment. The first step in the process of formulation of UAQMP is to identify the air quality control regions based on ambient air quality status and second, initiate a time bound program involving all stakeholders to develop UAQMPs. The successful implementation of UAQMPs depends on the strength of its key components, e.g. goal/objective, monitoring network, emission inventory, air quality modeling, control strategies and public participation. This paper presents a comprehensive review on UAQMPs, being implemented worldwide at different scales e.g., national (macro), city (medium), and local (micro).
Afficher plus [+] Moins [-]Modelling the transport and accumulation of floating marine debris in the Mediterranean basin
2015
Mansui, J. | Molcard, A. | Ourmières, Y.
In the era of plastic and global environmental issues, when large garbage patches have been observed in the main oceanic basins, this work is the first attempt to explore the possibility that similar permanent accumulation structures may exist in the Mediterranean Sea. The questions addressed in this work are: can the general circulation, with its sub-basins scale gyres and mesoscale instabilities, foster the concentration of floating items in some regions? Where are the more likely coastal zones impacted from open ocean sources?Multi-annual simulations of advected surface passive debris depict the Tyrrhenian Sea, the north-western Mediterranean sub-basin and the Gulf of Sirte as possible retention areas. The western Mediterranean coasts present very low coastal impact, while the coastal strip from Tunisia to Syria appears as the favourite destination. No permanent structure able to retain floating items in the long-term were found, as the basin circulation variability brings sufficient anomalies.
Afficher plus [+] Moins [-]Evaluation of the relationship between allergic diseases in school children at Seoul's roadside elementary schools and air pollution
2015
Lee, Chungsoo | Kim, Hohyun | Lim, Youngwook | Yang, Jiyeon | Yu, Seungdo | Lee, Jungsub | Chang, Junyoung | Son, Hyerim | Park, Jungwon | Shin, Dongchun
An elementary school is an important public place for children and it is where they spend most of their days. The objective of this study was to survey the environmental conditions at schools and to assess the relationship between air pollution and allergic diseases using the International Study of Asthma and Allergies in Childhood questionnaire. Nine elementary schools were selected and subsequently classified into three groups. The selection included two schools with no traffic-related or other pollutants, four schools situated near roads with six lanes, and three schools situated near beltways. Allergic diseases were assessed in a total of 6301 students. School zones with critical exposure to pollutants were selected within each school and were evaluated based on the levels of particulate matter, fine particulate matter, ozone, carbon monoxide, carbon dioxide, nitrogen dioxide, sulfur dioxide and black carbon. O3 and PM10 exposures were significantly associated with the prevalence of lifetime symptoms and diagnosis of asthma. O3 and PM10 exposures were also associated with lifetime symptoms, diagnosis, and 1-year physician diagnosis prevalence of allergic rhinitis. BC exposure was significantly associated with the rates of 1-year treatment of disease for allergic rhinitis. For schools located near sources of air pollution, the prevalence of lifetime symptoms for atopic dermatitis was significantly increased. Some symptoms of allergies were significantly increased at schools surrounded by a higher traffic volume. This study provides additional evidence that exposure to school zone air pollutants and traffic volume put school children at risk for childhood allergic diseases. Thus, strategies and actions are necessary to protect children in schools from exposure to environmental pollutants. In addition, future analysis to evaluate the relationship between traffic-related air pollution and the development of allergic diseases at more advanced ages are needed to confirm or refute these associations.
Afficher plus [+] Moins [-]Determinants on ambient PM2.5 infiltration in non-heating season for urban residences in Beijing: Building characteristics, interior surface coverings and human behavior
2015
Huang, Lihui | Hopke, Philip K. | Zhao, Weiping | Li, Mu
Ambient fine particulate matter (PM2.5) pollution is currently a major public health concern in Chinese urban areas. However, assessment of ambient PM2.5 exposure and its health effects is challenging in China because the exposure primarily occurs indoors. There is large inter-home variability of the fraction of ambient PM2.5 that penetrates indoors and remains airborne (Finf), and the factors influencing this variability are unknown. In this study, 24-h real-time indoor and outdoor PM2.5 mass concentrations were concurrently collected for 41 urban residences in the non-heating season. The Finf were estimated with steady-state and dynamic models derived from mass balance considerations. Multivariate statistical analyses were employed to examine the associations between Finf and 78 factors related to building characteristics, motor vehicle traffic, human behavior, meteorology, furnishings, and atmospheric/indoor chemistry. The estimate of Finf over the 24-h monitoring period with the steady-state model was 0.72 ± 0.01; the Finf estimate for single residences, using the dynamic model, were 0.59 ± 0.13 (N = 33). Two predictive models for Finf were constructed with categorical and numerical variables, respectively. The results revealed that building characteristics, traffic, wall and floor coverings, and human behavior had substantial influence on Finf in the non-heating season. The variance contributions of the determinants of traffic, wall and floor coverings, and human behavior were comparable to or even greater than those of the building characteristics.
Afficher plus [+] Moins [-]Tracking the origins of plastic debris across the Coral Sea: A case study from the Ouvéa Island, New Caledonia
2015
Maes, Christophe | Blanke, Bruno
Contamination of the marine environment by human-made plastic litter is a growing and global problem. Our study attempts to explain the presence of two plastic bottles beached on the Ouvéa Island, in the southwest Pacific Ocean, with trademarks from the Solomon Islands and Papua New Guinea (PNG). We simulate the oceanic drift tracks and associated transit times with a Lagrangian interpretation of the surface currents of a high-resolution ocean model. Our results show that it takes less than 2–3months for drifting objects to connect these archipelagos (New Caledonia, Solomon Islands and PNG) and highlight the role of the meridional component of the circulation rather than the dominant zonal jets. This study shows that the origin or traceability of trash represent valuable information that can be used to test and, ultimately, improve our understanding of ocean circulation.
Afficher plus [+] Moins [-]Satellite-based observations of unexpected coastal changes due to the Saemangeum Dyke construction, Korea
2015
Lee, Yoon-Kyung | Ryu, Joo-Hyung | Choi, Jong-Kuk | Lee, Seok | Woo, Han-Jun
Spatial and temporal changes around an area of conventional coastal engineering can be easily observed from field surveys because of the clear cause-and-effect observable in the before and after stages of the project. However, it is more difficult to determine environmental changes in the vicinity of tidal flats and coastal areas that are a considerable distance from the project. To identify any unexpected environmental impacts of the construction of Saemangeum Dyke in the area, we examined morphological changes identified by satellite-based observations through a field survey on Gomso Bay tidal flats (15km from Saemangeum Dyke), and changes in the suspended sediment distribution identified by satellite-based observations through a hydrodynamic analysis in the Saemangeum and Gomso coastal area. We argue that hydrodynamic changes due to conventional coastal engineering can affect the sedimentation pattern in the vicinity of tidal flats. We suggest that the environmental impact assessment conducted before a conventional coastal engineering project should include a larger area than is currently considered.
Afficher plus [+] Moins [-]Polluter identification with spaceborne radar imagery, AIS and forward drift modeling
2015
Longépé, N. | Mouche, A.A. | Goacolou, M. | Granier, N. | Carrère, L. | Lebras, J.Y. | Lozach, P. | Besnard, S.
This study defines and assesses a new operational concept to identify the origin of pollution at sea, based on Synthetic Aperture Radar, Automatic Identification System, and a forward drift model. As opposed to traditional methodologies where the SAR detected pollution is backtracked in the past, our approach assumes that all the vessels pollute all along their way. Based on all the AIS data flows, the forward-tracked simulated pollutions are then compared to the detected pollution, and the potential polluter can be finally identified. Case studies are presented to showcase its usefulness in a variety of maritime situations with a focus on orphan pollutions in a dense traffic area. Out of the identification of the suspected polluters, the age and eventually the type of the pollution can be retrieved.
Afficher plus [+] Moins [-]Sedimentology and geochemistry of mud volcanoes in the Anaximander Mountain Region from the Eastern Mediterranean Sea
2015
Talas, Ezgi | Duman, Muhammet | Küçüksezgin, Filiz | Brennan, Michael L. | Raineault, Nicole A.
Investigations carried out on surface sediments collected from the Anaximander mud volcanoes in the Eastern Mediterranean Sea to determine sedimentary and geochemical properties. The sediment grain size distribution and geochemical contents were determined by grain size analysis, organic carbon, carbonate contents and element analysis. The results of element contents were compared to background levels of Earth’s crust. The factors that affect element distribution in sediments were calculated by the nine push core samples taken from the surface of mud volcanoes by the E/V Nautilus. The grain size of the samples varies from sand to sandy silt. Enrichment and Contamination factor analysis showed that these analyses can also be used to evaluate of deep sea environmental and source parameters. It is concluded that the biological and cold seep effects are the main drivers of surface sediment characteristics from the Anaximander mud volcanoes.
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