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Marine debris ingestion by sea turtles (Testudines) on the Brazilian coast: an underestimated threat? 全文
2015
de Carvalho, Robson Henrique | Lacerda, Pedro Dutra | da Silva Mendes, Sarah | Barbosa, Bruno Corrêa | Paschoalini, Mariana | Prezoto, Fabio | de Sousa, Bernadete Maria
Assessment of marine debris ingestion by sea turtles is important, especially to ensure their survival. From January to December 2011, 23 specimens of five species of sea turtles were found dead or dying after being rehabilitated, along the coast of the municipality of Rio de Janeiro, Brazil. To detect the presence of marine debris in the digestive tract of these turtles, we conducted a postmortem examination from the esophagus until the distal portion of the large intestine for each specimen. Of the total number of turtles, 39% had ingested marine debris such as soft plastic, hard plastic, metal, polyethylene terephthalate (PET) bottle caps, human hair, tampons, and latex condoms. Five of the seven sea turtles species are found along the Brazilian coast, where they feed and breed. A large number of animals are exposed to various kinds of threats, including debris ingestion.
显示更多 [+] 显示较少 [-]Metal(loid)s in sediment, lobster and mussel tissues near historical gold mine sites 全文
2015
Walker, Tony R. | Grant, Jon
Previous studies near historical gold mining districts in Nova Scotia have identified significant enrichment of metal(loid)s in coastal marine sediments. Most of this inventory is buried below biologically active zones, although in some areas arsenic has bioaccumulated in marine biota resulting in localised bivalve shellfish closures. Isaacs Harbour is poised for future industrial development, but before potential impacts are predicted, current marine baseline conditions must be determined. To address this gap, this study established a baseline using surface sediments and biota (mussel and lobster tissues), to provide a broader picture of metal(loid)s in the marine environment. Results confirmed previous studies showing that most sediment metal(loid) concentrations still exceeded Canadian Marine Sediment Quality Guidelines, and also provided evidence of Canadian Food Inspection Agency fish tissue exceedances of arsenic in lobster and lead in mussel tissues indicating that some bioaccumulation of legacy contaminants in marine biota continues to the present day.
显示更多 [+] 显示较少 [-]Heavy metals distribution and environmental quality assessment for sediments off the southern coast of the Shandong Peninsula, China 全文
2015
Liu, Shanshan | Zhang, Yong | Bi, Shipu | Zhang, Xiaobo | Li, Xiaoyue | Lin, Manman | Hu, Gang
A systematic study was conducted on the distribution characteristics of heavy metals and on associated influencing factors in sediments off the southern coast of the Shandong Peninsula, China, based on the results of a heavy metals analysis on 157 surface sediment samples from coastal waters of the study area and on 46 samples from surrounding rivers flowing into the sea. An environmental quality assessment of heavy metals was performed using the Nemerow index. The results show that the distribution characteristics of sediment heavy metals in coastal waters outside of Qingdao can be divided into three classes: (1) Class I – Cr, Cu and Zn, with high-value areas extending from the northeast to the southwest in a banded or tongue-like pattern; (2) Class II – As, Cd and Pb, with high-value areas mainly distributed off the southeastern coast of Mt. Lao; and (3) Class III – Hg only, with high-value areas mainly in the northern area of Jiaozhou Bay. Integrated assessment based on the Nemerow index reveals that heavy metals pollution has occurred in surface sediments in a number of coastal water areas outside of Qingdao. This pollution is mainly found off the southeastern coast of Mt. Lao and in the northeastern section of Jiaozhou Bay. Results show that grain size of surface sediments, surrounding rivers and human activities are the main reasons for the element distribution pattern.
显示更多 [+] 显示较少 [-]Spatial representativeness of air quality monitoring stations: A grid model based approach 全文
2015
Piersanti, Antonio | Vitali, Lina | Righini, Gaia | Cremona, Giuseppe | Ciancarella, L. (Luisella)
A methodology for quantifying areas of spatial representativeness of air quality monitoring station is here proposed, exploiting the wide spatial and temporal coverage of chemical transport models results. The method is based on the analysis of time series of model concentrations, extracted at monitoring sites and around, by means of a Concentration Similarity Function (CSF). The method was tested on AMS-MINNI model results, covering Italy and three reference years (2003, 2005, 2007), for assessing the spatial representativeness of PM2.5 and O3 rural background monitoring stations. The CSF methodology shows good performances in describing both the extension and the shape of representativeness areas, taking into account the difference between pollutants and the dependence on averaging time and temporal interval of concentration data. Results show a large variability in the size and shape of the selected stations in Italy, ranging from 220 to 4500 km2. This confirms the importance of carrying out ad-hoc analyses on monitoring stations, as general a priori classifications and qualitative assessments of spatial representativeness are not able to fully capture the complexity of different territorial contexts.
显示更多 [+] 显示较少 [-]Development and laboratory evaluation of a compact swirling aerosol sampler (SAS) for collection of atmospheric bioaerosols 全文
2015
Wubulihairen, Maimaitireyimu | Lü, Xiaoying | Lee, Patrick K.H. | Ning, Zhi
Inhalation of infectious bioaerosols has been linked to a variety of respiratory diseases. However, efficient sampling techniques to allow high temporal resolution sampling are limited to collect and study bioaerosols in the various occupational and ambient micro–environmental atmospheres. This study introduces a medium flow swirling bioaerosol sampler (SAS) approach that collects atmospheric bioaerosols at the flow rate of 167 Lpm (10 cubic meter per hour). The collection of bioaerosols is achieved through a combination of impaction and cyclonic centrifugal motion. Aerosol deposition efficiency tests were performed with monodispersive polystyrene latex (PSL) particles ranging from 0.1 to 10 μm. Results have shown that the sampler has cut–off size of 0.7 μm and 1.5 μm, with and without the assistance of added water vapor, respectively. The bioaerosol collection and viability tests were performed with comparison to the commercially–available BioSampler, and the results show that the collection efficiency of the SAS is 97% at the designed flow rate, while the higher flow of the new system yields more than 13 times of the collection rate compared to the BioSampler. The high collection efficiency and observed viability preservation of the SAS make it an attractive alternative for high time resolution bioaerosol sampling for atmospheric, occupational and indoor air quality monitoring.
显示更多 [+] 显示较少 [-]Legal and institutional tools to mitigate plastic pollution affecting marine species: Argentina as a case study 全文
2015
González Carman, Victoria | Machain, Natalia | Campagna, Claudio
Plastics are the most common form of debris found along the Argentine coastline. The Río de la Plata estuarine area is a relevant case study to describe a situation where ample policy exists against a backdrop of plastics disposed by populated coastal areas, industries, and vessels; with resultant high impacts of plastic pollution on marine turtles and mammals. Policy and institutions are in place but the impact remains due to ineffective waste management, limited public education and awareness, and weaknesses in enforcement of regulations. This context is frequently repeated all over the world. We list possible interventions to increase the effectiveness of policy that require integrating efforts among governments, the private sector, non-governmental organizations and the inhabitants of coastal cities to reduce the amount of plastics reaching the Río de la Plata and protect threatened marine species. What has been identified for Argentina applies to the region and globally.
显示更多 [+] 显示较少 [-]Metal and metalloid concentrations in the tissues of dusky Carcharhinus obscurus, sandbar C. plumbeus and white Carcharodon carcharias sharks from south-eastern Australian waters, and the implications for human consumption 全文
2015
Gilbert, Jann M. | Reichelt-Brushett, Amanda J. | Butcher, Paul A. | McGrath, Shane P. | Peddemors, Victor M. | Bowling, Alison C. | Christidis, Les
Shark fisheries have expanded due to increased demand for shark products. As long-lived apex predators, sharks are susceptible to bioaccumulation of metals and metalloids, and biomagnification of some such as Hg, primarily through diet. This may have negative health implications for human consumers. Concentrations of Hg, As, Cd, Cu, Fe, Se and Zn were analysed in muscle, liver and fin fibres (ceratotrichia) from dusky Carcharhinus obscurus, sandbar Carcharhinus plumbeus, and white Carcharodon carcharias sharks from south-eastern Australian waters. Concentrations of analytes were generally higher in liver than in muscle and lowest in fin fibres. Muscle tissue concentrations of Hg were significantly correlated with total length, and >50% of sampled individuals had concentrations above Food Standards Australia New Zealand’s maximum limit (1mgkg−1ww). Arsenic concentrations were also of concern, particularly in fins. Results warrant further investigation to accurately assess health risks for regular consumption of shark products.
显示更多 [+] 显示较少 [-]Coastal waters environmental monitoring supported by river basin pluviometry and offshore wave data 全文
2015
Abramic, Andrej | Martínez-Alzamora, Nieves | González del Rio Rams, Julio | Ferrer Polo, José
Environmental monitoring in the scope of the Water Framework Directive 2000/60/EC (WFD) is usually expensive and requires considerable human effort. In this study, we analyzed data obtained by a WFD coastal waters monitoring network over a three-year period (35 campaigns), with the aim to ascertain is it possible to increase the monitoring efficiency and obtain more accurate results. As the trophic condition of the coastal waters of Valencia is primarily, but not entirely, determined by continental loads and hydrodynamic conditions, additionally we analyzed related river basin pluviometry (daily frequency) and oceanographic (one hour frequency) data. Chlorophyll a, salinity, rain and wave data time series were analyzed separately, to identify any possible pattern. Analyzing coastal water bodies integrating all four parameters, it is found strong interactions between coastal waters trophic conditions, sea hydrodynamics and related basin pluviometry. Eight phytoplankton biomass scenarios associated to environmental conditions are identified and finally developed basis for a new efficient monitoring strategy and more accurate coastal waters assessment.
显示更多 [+] 显示较少 [-]Evaluation of steelmaking slag as basal media for coastal primary producers 全文
2015
Akiyama, Yoshihiro B. | Yano, Hitomi | Koba, Kyohei | Katayama, Takahiro | Asaoka, Satoshi | Okuda, Tetsuji | Nakai, Satoshi | Yamamoto, Tamiji | Nishijima, Wataru
The use of granular steelmaking slag as a substitute for natural sand in the construction of tidal flats was investigated. Using an intertidal flat simulator, we evaluated dephosphorization slag mixed with 8% by dry weight of dredged sediment (DPS+DS) as a basal medium for the growth of benthic macro- and microalgae in comparison with silica sand mixed with 8% dredged sediment (SS+DS). Species compositions of macro- and microalgae were distinctly different between DPS+DS and SS+DS. The mean dry weight of macroalgae on DPS+DS was three orders of magnitude higher than that on SS+DS. Sediment shear strength and pH were higher in DPS+DS than in SS+DS or in the sediment of natural tidal flats. These results suggest that DPS contributes to changing the sediment environment, thereby changing the algal composition compared to the composition on natural tidal flats.
显示更多 [+] 显示较少 [-]Mapping the Global Dust Storm Records: Review of Dust Data Sources in Supporting Modeling/Climate Study 全文
2015
Wang, Julian X. L.
Dust storms, as extreme environmental events, are one of the Earth’s major natural hazards. Their impact on socio-economics can range from local urban to (trans-) continental and from minutes to decades, such as the dust bowl of the 1930s in the United States. Research on dust storms can be traced back for several decades as a meteorological extension. Latest technology developments have enabled comprehensive studies on dust storms, including sampling improvement, analytic studies, and numerical modeling. However, inhomogeneity of the data has hampered and sometimes even misguided research on comprehensive understanding of dust storms and exploring their feedbacks with climate. This review will focus on currently available observations of dust activities, which include routine meteorological records, in situ air chemistry observations, and satellite remote sensing. The aim is to show data sources and the status of their usage in a common framework for global dust regions. Emphasis is placed on data continuity and the spatial and temporal coverage of dust storms, since it is anticipated that this brief summary of dust data will benefit modeling and climate studies. Therefore, it must be noted that field campaign data are outside of the scope of the current review, although they play an important role in research and understanding.
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