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Characteristics of indoor air quality at urban elementary schools in Seoul, Korea: Assessment of effect of surrounding environments Texte intégral
2015
Yang, Jinho | Nam, Insick | Yun, Hyunjun | Kim, Jinman | Oh, Hyeon-Ju | Lee, Dohee | Jeon, Si-Moon | Yoo, Seung-Ho | Sohn, Jong-Ryeul
The indoor environment of schools where children stay for long periods of time is a matter of primary concern due to the vulnerability and sensibility of children to air pollutant exposure. The aims of this study were to characterize the indoor air quality of elementary schools in Seoul, Korea, to compare the indoor levels according to the surrounding environments and year of remodeling. The air pollutants, including particle matter (PM10), nitrogen dioxide (NO2), carbon monoxide (CO), carbon dioxide (CO2), total bacteria count (TBC), total volatile organic compounds (TVOC) and formaldehyde (HCHO), were sampled during autumn from classrooms and laboratories at 116 elementary schools employing natural ventilation. The schools were selected based on their surrounding environments: surrounded by buildings (SB), roadways (RW), and mountains (MT). The indoor air quality measured at elementary schools in Seoul, Korea showed generally low levels of pollutants due to low occupancy and adequate ventilation and the indoor levels of PM10 and TBC in schools near roadways were significantly lower than other surrounding environments due to dispersion of pollutants, without obstruction by buildings and mountains. TVOC and HCHO concentrations of schools remodeled within a year were significantly higher. Therefore, suitable management for school building characteristics is needed.
Afficher plus [+] Moins [-]Multivariate methods to predict ground level ozone during daytime, nighttime, and critical conversion time in urban areas Texte intégral
2015
Awang, Norrimi Rosaida | Nor Azam Ramli, | Yahaya, Ahmad Shukri | Elbayoumi, Maher
Ground–level ozone (O3) is known to exhibit strong daily variations that lead to complexity of the pollutants’ analysis and predictions. This study aimed to introduce and explore the variations in O3 concentrations during daytime (DT), nighttime (NT), and critical conversion time (CCT) using multiple linear regression (MLR) and principal component regression (PCR) analyses. The original variables and principal component analysis (PCA) results were used as the input for MLR analysis. Hourly averages of six air pollutants and four meteorological parameters at Shah Alam during 1999–2009 were selected for this study. The monitoring records in 2010 were used to assess the developed models using several performance indicators. Results showed that the MLR model during DT exhibited optimal performance in terms of normalized absolute error, index of agreement, prediction accuracy, and coefficient of determination (R2) with values of 0.2762, 0.9211, 0.8581, and 0.7354, respectively. PCR during CCT also showed significantly higher performance than that during DT and NT. This result was evidenced by higher percentage of total variances, which could be explained by the selected variables in PCA during CCT.
Afficher plus [+] Moins [-]More bang for your monitoring bucks: Detection and reporting of non-indigenous species Texte intégral
2015
Whomersley, P. | Murray, J.M. | McIlwaine, P. | Stephens, D. | Stebbing, P.D.
‘Collect once, use often’ is a frequently cited principle in both national and international efforts to promote the collection, archiving and sharing of marine monitoring data. Since the implementation of the Marine Conservation Zone (MCZ) evidence collection programme, 67 recommended MCZ sites have been visited and a suite of marine data collected. Here we present how this dataset was utilised outside of the MCZ programme to identify occurrences of non-indigenous species (NIS) around the UK coast. One hundred and thirty-five aquatic species from the Non-native Species Information Portal (NNSIP) register were used to produce a standard list of NIS against which, infauna and epifaunal data records from the MCZ project were compared. A total of 20 NIS were identified across 42 of the 67 sites surveyed. This study demonstrates that with sufficient coordination and management data collected for other purposes can be easily utilised to address additional policy requirements.
Afficher plus [+] Moins [-]Foraminiferal assemblages as bioindicators to assess potential pollution in mangroves used as a natural biofilter for shrimp farm effluents (New Caledonia) Texte intégral
2015
Debenay, J. P. | Marchand, C. | Molnar, N. | Aschenbroich, A. | Meziane, T.
In New Caledonia, semi-intensive shrimp farms release untreated effluents into the mangrove. Foraminiferal assemblages were analyzed for assessing the impact of effluent release on the benthic compartment. Comparison was made between samples collected (1) in an effluent receiving mangrove before and after the rearing cycle, and (2) for one-year monitoring an effluent receiving and a control mangrove. The distribution of foraminiferal assemblages was primarily driven by the gradient between Rhizophora stands and salt-flats, related to salinity and tidal elevation, and by seasonal cycles. The potential impact of effluent release was due to the combined effects of normal-saline effluents on surface salinity, and of nutrient input and microbial stimulation on food availability. Foraminiferal assemblages did not indicate a substantial impact of farm effluents and suggest that semi-intensive shrimp farming using mangrove for effluent discharge may appear as a sustainable solution in New Caledonia, when considering only the impact on the mangrove itself.
Afficher plus [+] Moins [-]Estimating the willingness to pay to protect coral reefs from potential damage caused by climate change—The evidence from Taiwan Texte intégral
2015
Tseng, William Wei-Chun | Hsu, Shu-Han | Chen, Chi-Chung
Coral reefs constitute the most biologically productive and diverse ecosystem, and provide various goods and services including those related to fisheries, marine tourism, coastal protection, and medicine. However, they are sensitive to climate change and rising temperatures. Taiwan is located in the central part of the world's distribution of coral reefs and has about one third of the coral species in the world. This study estimates the welfare losses associated with the potential damage to coral reefs in Taiwan caused by climate change. The contingent valuation method adopted includes a pre-survey, a face-to-face formal survey, and photo illustrations used to obtain reliable data. Average annual personal willingness to pay is found to be around US$35.75 resulting in a total annual willingness to pay of around US$0.43 billion. These high values demonstrate that coral reefs in Taiwan deserve to be well preserved, which would require a dedicated agency and ocean reserves.
Afficher plus [+] Moins [-]Levels and spatial distribution of perfluoroalkyl substances in China Liaodong Bay basin with concentrated fluorine industry parks Texte intégral
2015
Chen, Hong | Zhang, Can | Han, Jianbo | Sun, Ruijun | Kong, Xiangyun | Wang, Xiaomeng | He, Xin
Eighteen different perfluoroalkyl substances (PFASs) were investigated in 35 river water samples and 34 sediment samples collected from rivers in the Liaodong Bay basin containing two fluorine industry parks. Perfluorooctanoate (PFOA) and perfluorooctane sulfonate (PFOS) were the predominant PFASs in freshwater, with median concentrations of 26.5ng/L and 1.87ng/L, respectively. However, perfluorobutane sulfonate (PFBS) had the highest maximum concentration (up to 124.1ng/L, approximately two orders of magnitude higher) in water at a site which is the nearest to the industrial source of PFASs. Total PFASs in water at this site were also the highest. In contrast, PFOA and perfluorooctadecanoate (PFOcDA) were the most abundant PFASs in sediment, with median concentrations of 1.19ng/g and 0.35ng/g, respectively. Total PFAS concentrations in sediment from the site near to the industrial park were significantly higher than the other rivers. Mass loading of total PFASs from the rivers flowing into Liaodong Bay was estimated to be 506kg/year.
Afficher plus [+] Moins [-]Underwater noise assessment in the Gulf of Trieste (Northern Adriatic Sea, Italy) using an MSFD approach Texte intégral
2015
Codarin, Antonio | Picciulin, Marta
In the marine environment, underwater noise is one of the most widespread input of man-made energy. Recently, the European Commission has stressed the necessity of establishing threshold levels as a target for the descriptor 11.2.1 “Continuous low frequency sounds” in the Marine Strategy Framework Directive (MSFD). In 2012, a monthly underwater noise monitoring programme was conducted in the Gulf of Trieste (Northern Adriatic Sea, Italy); the collected acoustic samples (frequency range: 10–20,000Hz) were analysed in the 1/3 octave bands. The stations have been further clustered following the 63 and 125Hz bands noise levels. Average SPL levels resulted similar to those previously computed for proximate areas, indicating that the Adriatic Sea sub-region experiences high noise pressure in the marine waters. In its turn this claims for a scientific and technical international cooperation, as requested by the EU programme. No seasonal variation in local noise levels has been found.
Afficher plus [+] Moins [-]Mussel farming in Maliakos Gulf and quality indicators of the marine environment: Good benthic below poor pelagic ecological status Texte intégral
2015
Dimitriou, Panagiotis D. | Karakassis, Ioannis | Pitta, Paraskevi | Tsagaraki, Tatiana Margo | Apostolaki, Eugenia T. | Magiopoulos, Iordanis | Nikolioudakis, Nikolaos | Diliberto, Santi | Theodorou, John A. | Tzovenis, Ioannis | Kagalou, Ifigenia | Beza, Paraskevi | Tsapakis, Manolis
Biological and geochemical variables in the water column and sediments were monitored along a transect of a mussel farm located in a transitional environment in Maliakos Gulf, a semi-enclosed gulf in eastern Mediterranean. Analyses of water, sediment and macrofauna samples were used to calculate ecological status indicators in the context of the European Water Framework Directive. The water column ecological status was “Poor” or “Bad” showing little change with distance from the farm, but the ecological status of the benthic communities was found to be “Good,” although there were quantitative changes in macrofaunal indices with distance from the farm.
Afficher plus [+] Moins [-]Physiological perturbations in juvenile cuttlefish Sepia officinalis induced by subchronic exposure to dissolved zinc Texte intégral
2015
Le Pabic, Charles | Caplat, Christelle | Lehodey, Jean-Paul | Dallas, Lorna | Koueta, N. (Noussithé)
Although cephalopod early life stage development often occurs in coastal areas where contamination is real and continuous, the physiological perturbations induced by contaminants have been rarely investigated. This study focused on the Zn as it is one of the trace metals the most concentrated in coastal waters, worldwide. As Zn-tolerance limits were unknown in juvenile Sepia officinalis, the aim of this study was to estimate the threshold inducing mortality during the 2-first weeks post-hatching, and to determine its sensitivity using digestive and immune enzymatic assays, as well as growth and behavior follow-up during the first 5weeks post-hatching. Our study highlighted a Zn-mortality threshold lying between 185 and 230μgl−1, and growth reductions occurring after 5-week at 108μgl−1 and above, associated with enzymatic perturbations. These results underline a relatively important sensitivity of juvenile cuttlefish to Zn, pointed out by a wide diversity of biomarkers.
Afficher plus [+] Moins [-]Inputs of anthropogenic nitrogen influence isotopic composition and trophic structure in SE Australian estuaries Texte intégral
2015
Mazumder, Debashish | Saintilan, Neil | Alderson, Brendan | Hollins, Suzanne
Urban development in coastal settings has increased the input of nitrogen into estuaries globally, in many cases changing the composition of estuarine ecosystems. By focussing on three adjacent estuaries with a gradient of anthropogenic N loadings, we used stable isotopes of N and C to test for changes due to increased anthropogenic N input on the structure of some key trophic linkages in estuaries. We found a consistent enrichment in δ15N corresponding to increased anthropogenic N at the three ecosystem levels studied: fine benthic organic matter, grazing invertebrate, and planktivorous fish. The degree of enrichment in δ15N between fine benthic organic matter and the grapsid crab Parasesarma erythrodactyla was identical across the three sites. The glassfish Ambassis jacksoniensis showed lower levels of enrichment compared to basal food sources at the higher N-loaded sites, suggesting a possible effect of anthropogenic N in decreasing food-chain length in these estuaries.
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