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RETRACTION: Energy direct inputs and greenhouse gas emissions of the main industrial trawl fishery of Brazil
2014
Port, Dagoberto | Alvarez Perez, Jose Angel | de Menezes, João Thadeu
This article has been retracted: please see Elsevier Policy on Article Withdrawal (http://www.elsevier.com/locate/withdrawalpolicy).This article has been retracted at the request of the Editor-in-Chief and the Authors.This paper has to be retracted as the authors have noticed a procedural error with regards to their data which affects the results and discussion of the paper. It is important to note that this is not considered to be the result of scientific misconduct, but rather honest errors by the authors.
显示更多 [+] 显示较少 [-]The use of cholinesterase as potential biomarker: In vitro characterization in the polychaete Capitella teleta
2014
Gomes, Isa D.L. | Lemos, Marco F.L. | Soares, Amadeu M.V.M. | Barata, Carlos | Faria, Melissa
The ecological relevance of polychaetes coupled with their easy culture and maintenance in the laboratory, has led them to become increasingly used in marine ecotoxicological studies, raising the need to validate frequently applied monitoring tools at various biological levels. The present study was aimed to characterize the cholinesterases (ChE) activity in the polychaete Capitella teleta, using three substrates (acetylthiocholine iodide, propionylthiocholine iodide, and S-butyrylthiocholine iodide) and four known inhibitors (eserine hemisulfate, BW284c51, iso-OMPA and chlorpyrifos-oxon). Results showed that most of the measured cholinesterase activity was acetylcholinesterase (AChE). Inhibition of enzyme kinetic experiments denoted that sensitivity of C. teleta’s ChE to the organophosphorous metabolite chlorpyrifos-oxon (IC50=60.72nM) was analogous to some fish species. This study highlights the relevance of ChE characterization before its use as a biomarker in ecotoxicology and biomonitoring studies.
显示更多 [+] 显示较少 [-]Marine mammals and ocean noise: Future directions and information needs with respect to science, policy and law in Canada
2014
Williams, Rob | Ashe, Erin | Blight, Louise | Jasny, Michael | Nowlan, Linda
Marine mammals are ecologically and culturally important species, and various countries have specific legislation to protect the welfare of individual marine mammals and the conservation of their populations. Anthropogenic noise represents a particular challenge for conservation and management. There is a large and growing body of research to support the conclusion that anthropogenic noise can affect marine mammal behavior, energetics, and physiology. The legal, policy, and management issues surrounding marine mammals and noise are similarly complex. Our objective is twofold. First, we discuss how policy and legal frameworks in Canada have some important differences from other jurisdictions covered in previous reviews, and provide a useful general case study. Secondly, we highlight some priority research areas that will improve marine mammal conservation and management. Our examples focus on the research needed to meet stated conservation objectives for marine mammal species in waters under Canadian jurisdiction.
显示更多 [+] 显示较少 [-]Assessment of photochemical processes in marine oil spill fingerprinting
2014
Radović, Jagoš R. | Aeppli, Christoph | Nelson, Robert K. | Jiménez, Nuria | Reddy, Christopher M. | Bayona, Josep M. | Albaigés, Joan
Understanding weathering processes plays a critical role in oil spill forensics, which is based on the comparison of the distributions of selected compounds assumed to be recalcitrant and/or have consistent weathering transformations. Yet, these assumptions are based on limited laboratory and oil-spill studies. With access to additional sites that have been oiled by different types of oils and exposures, there is a great opportunity to expand on our knowledge about these transformations. Here, we demonstrate the effects of photooxidation on the overall composition of spilled oils caused by natural and simulated sunlight, and particularly on the often used polycyclic aromatic hydrocarbons (PAHs) and the biomarker triaromatic steranes (TAS). Both laboratory and field data from oil released from the Macondo well oil following the Deepwater Horizon disaster (2010), and heavy fuel-oil from the Prestige tanker spill (2002) have been obtained to improve the data interpretation of the typical fingerprinting methodology.
显示更多 [+] 显示较少 [-]Dependence of eelgrass (Zostera marina) light requirements on sediment organic matter in Massachusetts coastal bays: Implications for remediation and restoration
2014
Kenworthy, W.J. | Gallegos, C.L. | Costello, Charles | Field, Donald | di Carlo, Giuseppe
Using a calibrated bio-optical model we determined that the optical water quality conditions in several nitrogen-impaired embayments and in one unimpaired system were within the range of values known to support eelgrass growth. We also used the model to identify a range of light requirements for eelgrass (Zostera marina). Higher eelgrass light requirements, expressed as a percentage of surface-incident irradiance, corresponded with higher sediment organic matter content. These results corroborated findings by previous studies which indicate a generalized relationship: seagrasses growing in turbid conditions with poorer water and sediment quality have higher light requirements than those growing in less degraded conditions. The mechanistic reason for the variation in light requirements is still not completely explained and cannot be attributed to a single independent variable. Varying light requirement have important implications for eelgrass protection and should be considered when setting restoration targets for eelgrass in water quality and nitrogen remediation programs.
显示更多 [+] 显示较少 [-]Analysis of total column ozone in Peninsular Malaysia retrieved from SCIAMACHY
2014
Tan, Kok Chooi | Lim, Hwee San | Mat Jafri, Mohd Zubir
Due to lack of observational studies on greenhouse gases in Malaysia, most studies in this field were carried out based on ground station data. These studies did not utilize satellite data from the equatorial area. Satellite remote sensing is one of the most effective approaches for greenhouse gas distribution monitoring on a global scale. As such, satellite remote sensing exhibits a very high spatial and temporal resolution. Variations of ozone concentrations in Peninsular Malaysia were observed and investigated by means of data retrieved from the Scanning Imaging Absorption Spectrometer for Atmospheric Chartography (SCIAMACHY). The aim of this study was to determine the monthly and seasonal ozone concentrations in Peninsular Malaysia from January 2003 to December 2009. We utilized total column ozone at level 2 of the WFMD version 1.0. A spatial resolution value of 1°×1.25° was used. Analysis indicated that the five selected sites exhibited strong seasonal atmospheric ozone concentration variations. These variations resulted from the significant differences between the northeast monsoon (NEM) and the southwest monsoon (SWM). As the NEM prevails, cold air breaks out from Siberia and spreads to the equatorial region in the form of northeasterly cold surge winds. These winds manifest in low–level anticyclones over Southeast Asia. Inversely, the air masses from the southwest contribute to long–range air pollution. During SWM, the transport of atmospheric ozone by wind is associated with biomass burning in Sumatra, Indonesia. HYSPLIT was also utilized to identify the air pollutant transport between NEM and SWM toward Peninsular Malaysia. Comparisons were made between the ozone data from five sites in 2009. Data were retrieved from SCIAMACHY and the Atmospheric Infrared Sounder (AIRS). The relative difference average of the ozone data measured by SCIAMACHY and AIRS was approximately 6%.
显示更多 [+] 显示较少 [-]Using principal component analysis and fuzzy c–means clustering for the assessment of air quality monitoring
2014
Dogruparmak, Senay Cetin | Keskin, Gulsen Aydin | Yaman, Selin | Alkan, Atakan
Determining whether a reduction can be made in the total number of monitoring stations within the Air Quality Monitoring Network is very important since in case of necessity, the devices at one group of stations having similar air pollution characteristics can be transferred to another zone. This would significantly decrease the capital investment and operational cost. Therefore, the objective of this study was grouping the monitoring stations that share similar air pollution characteristics by using the methods of principal component analysis (PCA) and fuzzy c– means (FCM). In addition, this study also enables determining the emission sources, evaluating the performances of the methods and examining the zone in terms of pollution. In the classification of monitoring stations, different groups were formed depending on both the method of analysis and the type of pollutants. As a result of PCA, 5 and 3 classes have been determined for SO2 and PM10, respectively. This shows that the number of monitoring stations can be decreased. When reduced classes were analyzed, it was observed that a clear distinction cannot be made considering the affected source type. During the implementation of the FCM method, in order to facilitate comparison with the PCA, the monitoring stations were classified into 5 and 3 groups for SO2 and PM10, respectively. When the results were analyzed, it was seen that the uncertainty in PCA was reduced. When the two methods are compared, FCM was found to provide more significant results than PCA. The evaluation in terms of pollution, the results of the study showed that PM10 exceeded the limit values at all the monitoring stations, and SO2 exceeded the limit values at only 3 of the 22 stations.
显示更多 [+] 显示较少 [-]The PAH level, distribution and composition in surface sediments from a Mediterranean Lagoon: The Marano and Grado Lagoon (Northern Adriatic Sea, Italy)
2014
Acquavita, Alessandro | Falomo, Jari | Predonzani, Sergio | Tamberlich, Francesco | Bettoso, Nicola | Mattassi, Giorgio
The Marano and Grado Lagoon is one of the best conserved transitional environment in the whole Mediterranean area. On the other hand, it suffers from industrial, agricultural and fisheries activities, which could have an important impact on its environmental quality. With the application of the WFD, the sediment chemical status was investigated. In this work, 16 polycyclic aromatic hydrocarbons included by the US EPA within the priority pollutants were considered. PAHs values ranged from non-detectable to 1056ngg−1 showing the highest contamination close to the Aussa-Corno River mouth, which received the industrial inputs. The contamination level was comparable to that observed in low contaminated sites of the Mediterranean region, and lower than the adjacent Gulf of Trieste. The ratios of selected PAHs congeners pointed out the prevalence of pyrolitic sources. Moreover, the application of the ERL/ERM displayed an environment, which should not have a potential biological impact.
显示更多 [+] 显示较少 [-]Temporal trends and bioavailability assessment of heavy metals in the sediments of Deception Bay, Queensland, Australia
2014
Brady, James P. | Ayoko, G. A. (Godwin A.) | Martens, Wayde N. | Goonetilleke, Ashantha
Thirteen sites in Deception Bay, Queensland, Australia were sampled three times over a period of 7months and assessed for contamination by a range of heavy metals, primarily As, Cd, Cr, Cu, Pb and Hg. Fraction analysis, enrichment factors and Principal Components Analysis–Absolute Principal Component Scores (PCA–APCS) analysis were conducted in order to identify the potential bioavailability of these elements of concern and their sources. Hg and Te were identified as the elements of highest enrichment in Deception Bay while marine sediments, shipping and antifouling agents were identified as the sources of the Weak Acid Extractable Metals (WE-M), with antifouling agents showing long residence time for mercury contamination. This has significant implications for the future of monitoring and regulation of heavy metal contamination within Deception Bay.
显示更多 [+] 显示较少 [-]The impact of water temperature on water quality indexes in north of Liaodong Bay
2014
Kong, Xiangpeng | Ye, Shuhong
The north of Liaodong Bay is one of the most severely polluted areas in Bohai Sea. Because the self-purification capacity from the sea water exchange process is limited, the pollutants from the land and river sources cannot be completed degraded and an obviously contaminated zone was formed in the north of Liaodong Bay. Therefore the self-purification capacity from biological process is essential for maintaining ecosystem balance. Marine heterotrophic bacteria play an important role in degradation of the dissolved organic matters and constitution of the primary production in the coastal areas. The shift of water temperature between winter and summer is about 28°C in the north of Liaodong Bay, which causes changes in the self-purification capacity of the sea area. Certain indexes of water quality in Liaodong Bay were investigated in order to detect how these indexes response to the changing of water temperature. The experimental results show that COD, DO and the concentration of fecal coliform vary a little with the changing of water temperature; TBC increases dramatically when the water temperature is over 16°C; and TBC in summer is 30 times more than that in winter. By this study, the paper provides a reference to assess the environmental purification capacity of the sea area during different seasons.
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