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Spatiotemporal characteristics and health effects of air pollutants in Shenzhen Texte intégral
2016
Wu, Yongsheng | Zhang, Fengying | Shi, Yu | Pilot, Eva | Lin, Lanyu | Fu, Yingbin | Krafft, Thomas | Wang, Wuyi
In this study, spatiotemporal patterns and health effects in all-cause mortality of air pollutants (CO, NO2, and SO2) during 2013 in Shenzhen were investigated. Spatiotemporal characteristics of air quality index (AQI) and air quality are also addressed. The results show that daily averages were 10.9 μg/m3 for SO2, 39.6 μg/m3 for NO2, and 1.2 mg/m3 for CO. Daily AQI ranged from 24 to 179. There were approximately 39 days of air pollution in Shenzhen. NO2 was the third major air pollutant. Monthly/hourly average AQI and concentrations of NO2 and SO2 in the city center area were higher than in tourist areas. Annual AQI and NO2 concentration were higher in western parts of Shenzhen, whereas SO2 was higher in eastern portions. The lowest CO concentration was in the Luohu District. Relative risks of mortality number increased with SO2/NO2 levels. When SO2/NO2 concentration changed, female individuals were more sensitive than male individuals, and people aged older than 65 years were more affected than younger people.
Afficher plus [+] Moins [-]Assessment of bioavailable hydrocarbons in Pribilof Island rock sandpiper fall staging areas and overwintering habitat Texte intégral
2016
Nesvacil, Kelly | Carls, Mark | Holland, Larry | Wright, Sadie
At present, significant adverse hydrocarbon influence on the Pribilof Island rock sandpiper (Calidris ptilocnemis ptilocnemis) is unlikely. Almost the entire population overwinters in Cook Inlet and breeds on four Bering Sea islands. Passive samplers deployed several times in a three year period and corresponding sediment and soft tissue samples on St. Paul Island and in Cook Inlet generally accumulated small quantities of polycyclic aromatic hydrocarbons (PAHs). Composition was consistent with oil in <15% of the passive samplers and rarely in soft tissue. Total PAH concentrations in corresponding sediment were very low (<42ng/g dry weight); composition was consistent with oil in 39% of these samples and biomarker composition confirmed this on St. Paul Island. However, composition was dominated by normal alkanes from natural sources.
Afficher plus [+] Moins [-]Controlling populations of invasive pygmy mussel (Xenostrobus securis) through citizen science and environmental DNA Texte intégral
2016
Miralles, Laura | Dopico, Eduardo | Devlo-Delva, Floriaan | García Vázquez, Eva
Controlling populations of invasive pygmy mussel (Xenostrobus securis) through citizen science and environmental DNA Texte intégral
2016
Miralles, Laura | Dopico, Eduardo | Devlo-Delva, Floriaan | García Vázquez, Eva
Early detection of dangerous exotic species is crucial for stopping marine invasions. The New Zealand pygmy mussel Xenostrobus securis is a problematic species in coasts of temperate regions in the northern hemisphere. In this study we have controlled a population of this invader that recently expanded in a north Iberian estuary with both a participatory approach involving researchers and citizens, and employing a sensitive eDNA-based tool to monitor the population expansion in the estuary. Results demonstrate successful eradication of pygmy mussels in the outer part of the estuary with citizen science and the practical utility of eDNA for controlling biological invasions.
Afficher plus [+] Moins [-]Controlling populations of invasive pygmy mussel (Xenostrobus securis) through citizen science and environmental DNA Texte intégral
2016
Miralles López, Laura | Dopico Rodríguez, Eduardo Vicente | Devlo-Delva, F. | García Vázquez, Eva
This study has been supported by the Port of Aviles Authorities (contract FUO-EM-261-15), and the Spanish Ministry of Economy and Competitiveness Grant CGL-2013-42415-R. This is a contribution from the Asturias Marine Observatory. FDD is grateful to EMBC (Marine Biodiversity and Conservation Master).
Afficher plus [+] Moins [-]Underwater soundscape of marine protected areas in the south Brazilian coast Texte intégral
2016
Sánchez-Gendriz, I. | Padovese, L.R.
The Laje de Santos Marine State Park (LSMSP) and Xixová-Japuí State Park (XJSP) are two protected areas (PA), close to the Santos Bay in the south Brazilian coast. The region encompasses both important biodiversity and anthropogenic activities. This study aims to serve as a first reference survey of the underwater soundscape of these PAs. Additionally it evaluates the presence of the anthropogenic and biological sound in these areas. One month of continuous recorded underwater sound, at selected locations in XJSP and LSMSP, is used in this study. The data were characterized by its spectral content and by the temporal evolution of Sound Pressure Levels (SPL). Both locations showed sound events with daily periodicities, mainly related with boats and fish chorus.
Afficher plus [+] Moins [-]Aliphatic and polycyclic aromatic hydrocarbons risk assessment in coastal water and sediments of Khark Island, SW Iran Texte intégral
2016
Akhbarizadeh, Razegheh | Moore, Farid | Keshavarzi, Behnam | Moeinpour, Alireza
The potential sources and ecotoxicological risks of 26 aliphatic hydrocarbons (AHs), 16 polycyclic aromatic hydrocarbons (PAHs) and total petroleum hydrocarbons (TPHs) were investigated in coastal water and sediments of Khark Island, SW Iran. The major sources of the contamination were petroleum and petroleum combustion based on the PCA analysis and diagnostic indices of AHs and PAHs, and also ring classification of PAHs. The ecological risk of both individual and multiple PAHs was quite low in sediments compared with screening benchmarks. Likewise, the low concentration of TEQ, MEQ and TEQcarc of sediments suggest low toxicity of PAHs in the study area. However, environmental control is recommended to reduce the pollution burden of PAHs in seawater. The human health risk assessment for PAHs through dermal adsorption indicated that the possibility of negative adverse effects of PAHs in sediments is rare but swimming in the vicinity of industrial facilities should be done cautiously.
Afficher plus [+] Moins [-]Predicting pollutant concentrations in the water column during dredging operations: Implications for sediment quality criteria Texte intégral
2016
Wasserman, Julio Cesar | Wasserman, Maria Angélica V. | Barrocas, Paulo Rubens G. | Almeida, Aline Mansur
The development of new dredging techniques that can reduce, or at least predict, the environmental impacts, is in high demand by governments in developing countries. In the present work, a new methodology was developed, to evaluate the level of metals contamination (i.e. cadmium, lead and zinc) of the water column, during a dredging operation. This methodology was used to evaluate the impacts of the construction of a new maritime terminal in Sepetiba Bay, Brazil. The methodology quantifies the amount of resuspended sediments and calculates the expected contaminants concentrations in the water column. The results indicated that sediment quality criteria were not compatible with water quality criteria, because the dredging of contaminated sediments does not necessarily yield contaminated water. It is suggested that the use of sediment quality criteria for dredging operations might be abandoned, and the methodology presented in this study applied to assess dredging's environmental impacts, predicting water contamination levels.
Afficher plus [+] Moins [-]Organochlorine compounds in surface sediments from the northern coast of Cyprus, Eastern Mediterranean: Levels, possible sources and potential risk Texte intégral
2016
Kucuksezgin, F. | Pazi, I. | Gonul, L.T. | Duman, M.
Organochlorines (OCs) were determined in sediments collected from different regions of northern coast of Cyprus. The OCPs and Aroclors had a wide range from 2.78 to 306 and 15 to 325ngg−1, respectively. The highest level was found at Yedi Dalga site. DDE was the most abundant compound. The ratios of metabolites to parent DDT showed that DDTs were derived mostly from the aged and weathered inputs. Comparing our results with the previous studies showed that POPs in sediments were found to be lower than those in samples for Mediterranean and Black Sea coasts. The SQG implied that, Aroclor1254 exceeded the TEL values, showing that adverse biological effects are expected occasionally at some of the sediment samples. DDTs were dominant and more ecotoxicological concern in the northern Cyprus. Altogether, it may be summarized that DDTs will impose ecologically hazardous impacts in the sedimentary environment at the present.
Afficher plus [+] Moins [-]Horizontal gene transfer versus biostimulation: A strategy for bioremediation in Goa Texte intégral
2016
Pasumarthi, Rajesh | Mutnuri, Srikanth
Bioaugmentation, Biostimulation and Horizontal gene transfer (HGT) of catabolic genes have been proven for their role in bioremediation of hydrocarbons. It also has been proved that selection of either biostimulation or bioremediation varies for every contaminated site. The reliability of HGT compared to biostimulation and bioremediation was not tested. The present study focuses on reliability of biostimulatiion, bioaugmentation and HGT during biodegradation of Diesel oil and Non aqueous phase liquids (NAPL). Pseudomonas aeruginosa (AEBBITS1) having alkB and NDO genes was used for bioaugmentation and the experiment was conducted using seawater as medium. Based on Gas chromatography results diesel was found to be degraded to 100% in both presence and absence of AEBBITS1. Denturing gradient gel electrophoresis result showed same pattern in presence and absence of AEBBITS1 indicating no HGT. NAPL degradation was found to be more by Biostimulated Bioaugmentation compared to biostimulation and bioaugmentation alone. This proves that biostimulated bioaugmentation is better strategy for oil contamination (tarabll) in Velsao beach, Goa.
Afficher plus [+] Moins [-]The effects of urbanization and household-related factors on residential direct CO2 emissions in Shanxi, China from 1995 to 2014: A decomposition analysis Texte intégral
2016
Zang, Xueling | Zhao, Tao | Wang, Juan | Guo, Fang.
Multiple household-related driving factors of residential direct carbon emissions (RDCE) in China at regional level have not yet been sufficiently addressed or quantified. In this paper, a logarithmic mean Divisia index (LMDI) decomposition analysis was employed to examine the factors (e.g., the number of households, per capita household income, household size, urbanization, energy intensity, energy structure and emission coefficient) impacting the changes in RDCE in Shanxi province of China from 1995 to 2014. The results showed that the increase in RDCE mainly attributed to the growing per capita household income and the increasing number of households. Additionally, the expansion of urbanization also contributed marginally to the increase in emissions. However, the shrinking household size was a main inhibitory factor and the decline in energy intensity was also responsible for the diminishing emissions. Based on the results, four emission reduction measures and strategies were identified: (i) using market economic mechanism to regulate household consumption behaviors towards environment protection and low carbon development, as well as encouraging the use of energy-efficiency domestic appliances and less energy-intensive lifestyles; (ii) setting strict divorce processes to lower divorce rates and encouraging people to live with their children and parents; (iii) realizing green transformation development of urbanization; (iv) promoting a shift to renewable and clean energy in people's daily life and power generation, e.g., wind, solar, hydro, nuclear and biogas.
Afficher plus [+] Moins [-]One-century decline of mollusk diversity as consequence of accumulative anthropogenic disturbance in a tropical estuary (Cuban Archipelago) Texte intégral
2016
Armenteros, Maickel | Díaz-Asencio, Misael | Fernández-Garcés, Raúl | Hernández, Carlos Alonso | Helguera-Pedraza, Yusmila | Bolaños-Alvarez, Yoelvis | Agraz-Hernández, Claudia | Sanchez-Cabeza, Joan-Albert
In order to infer changes in sediments and mollusk assemblages for the last century, we used biogeochemical data from two 210Pb dated cores collected in Sagua La Grande estuary, Cuban Archipelago. We found evidences of cumulative anthropogenic disturbance during the last century, causing considerable depletion of mollusk assemblage diversity and enhancement of the dominance of deposit feeding species. The sequence of impacts assessed was i) eutrophication due to nutrient releases from urban settlements, ii) habitat alteration due to water channeling and damming, and iii) mercury pollution. These successive impacts caused a steady diversity depletion from ca. 70 mollusk species in 1900 to less than five in 2010. Only two species persisted in the estuary: Nuculana acuta and Finella dubia. Hurricanes did not impact the molluscan fauna in the long term. The effects of the anthropogenic impacts suggest that the resilience of this estuarine system is compromised.
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