Уточнить поиск
Результаты 661-670 из 2,529
Real time observation system for monitoring environmental impact on marine ecosystems from oil drilling operations Полный текст
2014
Godø, Olav Rune | Klungsøyr, Jarle | Meier, Sonnich | Tenningen, Eirik | Purser, Autun | Thomsen, Laurenz
Environmental awareness and technological advances has spurred development of new monitoring solutions for the petroleum industry.This paper presents experience from a monitoring program off Norway. To maintain operation within the limits of the government regulations Statoil tested a new monitoring concept. Multisensory data were cabled to surface buoys and transmitted to land via wireless communication. The system collected information about distribution of the drilling wastes and the welfare of the corals in relation to threshold values.The project experienced a series of failures, but the backup monitoring provided information to fulfil the requirements of the permit. The experience demonstrated the need for real time monitoring and how such systems enhance understanding of impacts on marine organisms. Also, drilling operations may improve by taking environmental information into account. The paper proposes to standardize and streamline monitoring protocols to maintain comparability during all phases of the operation and between drill sites.
Показать больше [+] Меньше [-]Severity of killer whale behavioral responses to ship noise: A dose–response study Полный текст
2014
Critical habitats of at-risk populations of northeast Pacific “resident” killer whales can be heavily trafficked by large ships, with transits occurring on average once every hour in busy shipping lanes. We modeled behavioral responses of killer whales to ship transits during 35 “natural experiments” as a dose–response function of estimated received noise levels in both broadband and audiogram-weighted terms. Interpreting effects is contingent on a subjective and seemingly arbitrary decision about severity threshold indicating a response. Subtle responses were observed around broadband received levels of 130dB re 1μPa (rms); more severe responses are hypothesized to occur at received levels beyond 150dB re 1μPa, where our study lacked data. Avoidance responses are expected to carry minor energetic costs in terms of increased energy expenditure, but future research must assess the potential for reduced prey acquisition, and potential population consequences, under these noise levels.
Показать больше [+] Меньше [-]The distribution of dissolved lead in the coastal waters of the East China Sea Полный текст
2014
The distribution of dissolved lead in the coastal waters of the East China Sea was investigated seasonally. The average concentrations in surface waters during the spring and autumn were 0.52nM and 0.27nM, respectively. In the spring, the concentration of dissolved Pb in the surface waters and bottom waters ranged from 0.13 to 1.86nM and from 0.15 to 0.94nM, respectively. For both the surface water and the bottom water, the highest values were observed at the Yangtze River Estuary. Seasonal variability of D-Pb between spring and autumn in the ECS was observed. These results suggested that riverine inputs and atmospheric inputs may be the main sources of lead in this area, while adsorption and co-precipitation on suspended particles at the river estuary and biological process may be the major sinks.
Показать больше [+] Меньше [-]Out of sight but not out of mind: Harmful effects of derelict traps in selected U.S. coastal waters Полный текст
2014
Arthur, Courtney | Sutton-Grier, Ariana E. | Murphy, Peter | Bamford, Holly
There is a paucity of data in the published literature on the ecological and economic impacts of derelict fishing traps (DFTs) in coastal ecosystems. We synthesized results from seven NOAA-funded trap fisheries studies around the United States and determined that DFT-caused losses to habitat and harvestable annual catch are pervasive, persistent, and largely preventable. Based on this synthesis, we identified key gaps to fill in order to better manage and prevent DFTs. We conclude with suggestions for developing a U.S. DFT management strategy including: (1) targeting studies to estimate mortality of fishery stocks, (2) assessing the economic impacts of DFTs on fisheries, (3) collaborating with the fishing industry to develop solutions to ghost fishing, and (4) examining the regional context and challenges resulting in DFTs to find effective policy solutions to manage, reduce, and prevent gear loss.
Показать больше [+] Меньше [-]Microbial release from seeded beach sediments during wave conditions Полный текст
2014
Phillips, Matthew C. | Feng, Zhixuan | Vogel, Laura J. | Reniers, Ad J.H.M. | Haus, Brian K. | Enns, Amber A. | Zhang, Yifan | Hernandez, David B. | Solo-Gabriele, Helena M.
Beach sands can sustain indigenous and introduced populations of enterococci. The objective of this study was to evaluate wave action in promoting the release of introduced bacteria. To accomplish this objective this study developed a method to assess attachment and identified conditions under which introduced bacteria are integrated into the sand. A new “shearing assay” showed that attachment of the introduced spike mimicked that of the natural sand when the spike was allowed to integrate into the sand for 24h at room temperature at a sand moisture content of 20%. Experiments in a wave flume showed that waves were capable of releasing about 60% of the total bacteria added. This suggests that for the range of wave conditions evaluated (height: 1.9–10.5cm, period:1–2.7s), waves were incapable of releasing all of the bacteria. Further study is needed to evaluate bacteria attachment mechanisms.
Показать больше [+] Меньше [-]The interaction between organic phosphate ester and p53: An integrated experimental and in silico approach Полный текст
2014
Li, Fei | Li, Renmin | Yang, Xianhai | You, Liping | Zhao, Jianmin | Wu, Huifeng
Concerns have been raised in regards to the environmental impact of the more used organophosphate flame retardants (OPFRs). In this study, to better understand the relationship between molecular structural features of OPFRs and binding affinity for the tumor suppressor p53, an integrated experimental and in silico approach was used. From docking analysis, hydrogen bonding and hydrophobic interactions were found to be the dominant interactions, which implied the binding affinities of the compounds. The binding constants of 5 OPFRs were determined by surface plasmon resonance technology (SPR). Based on the observed interactions, appropriate molecular structural parameters were adopted to develop a quantitative structure-activity relationship (QSAR) model. The developed QSAR model had good robustness, predictive ability and mechanism interpretability. The interactions between the OPFRs and p53 (Ebinding) and the partition ability of the OPFRs into the bio-phase are main factors governing the binding affinities.
Показать больше [+] Меньше [-]Polychlorinated biphenyls (PCBs) and hexachlorobenzene (HCB) in the equatorial Indian Ocean: Temporal trend, continental outflow and air–water exchange Полный текст
2014
Nineteen pairs of air and seawater samples collected from the equatorial Indian Ocean onboard the Shiyan I from 4/2011 to 5/2011 were analyzed for PCBs and HCB. Gaseous concentrations of ∑ICESPCBs (ICES: International Council for the Exploration of the Seas) and HCB were lower than previous data over the study area. Air samples collected near the coast had higher levels of PCBs relative to those collected in the open ocean, which may be influenced by proximity to source regions and air mass origins. Dissolved concentrations of ∑ICESPCBs and HCB were 1.4–14pgL−1 and 0.94–13pgL−1, with the highest concentrations in the sample collected from Strait of Malacca. Fugacity fractions suggest volatilization of PCBs and HCB from the seawater to air during the cruise, with fluxes of 0.45–34ngm−2d−1 and 0.36–18ngm−2d−1, respectively.
Показать больше [+] Меньше [-]Carbonyl concentrations from sites affected by emission from different fuels and vehicles Полный текст
2014
Concentrations of carbonyl compounds were evaluated on places impacted by emissions from different fuels and vehicles. In order to evaluate the concentrations, four campaigns during the winter and summer of 2011 and 2012 were performed, inside a covered parking area in a commercial establishment where mainly gasohol and ethanol vehicles are in circulation. Also, measurements were done inside a semi–closed bus station, which is the direct source of emissions from heavy duty vehicles (i.e. buses) burning B3–diesel (3% biodiesel and 97% diesel). The results indicated that acetaldehyde is the main aldehyde emitted by light vehicles due to large use of ethanol in Brazil by these vehicles. In addition, the concentrations found in the bus station revealed that B3–diesel fuel increases the emissions of carbonyl compounds and that of acetaldehyde when compared with results from B0–diesel at same bus station. Possible impacts of changing diesel to B3–diesel indicate an increase of ozone formation. In terms of health, a lower impact was estimated considering only the changes in formaldehyde concentrations.
Показать больше [+] Меньше [-]Microplastic pollution in the Northeast Atlantic Ocean: Validated and opportunistic sampling Полный текст
2014
Levels of marine debris, including microplastics, are largely un-documented in the Northeast Atlantic Ocean. Broad scale monitoring efforts are required to understand the distribution, abundance and ecological implications of microplastic pollution. A method of continuous sampling was developed to be conducted in conjunction with a wide range of vessel operations to maximise vessel time. Transects covering a total of 12,700km were sampled through continuous monitoring of open ocean sub-surface water resulting in 470 samples. Items classified as potential plastics were identified in 94% of samples. A total of 2315particles were identified, 89% were less than 5mm in length classifying them as microplastics. Average plastic abundance in the Northeast Atlantic was calculated as 2.46particlesm−3. This is the first report to demonstrate the ubiquitous nature of microplastic pollution in the Northeast Atlantic Ocean and to present a potential method for standardised monitoring of microplastic pollution.
Показать больше [+] Меньше [-]Radioactivity concentrations in mussel (Mytilus galloprovincialis) of Turkish Sea coast and contribution of 210Po to the radiation dose Полный текст
2014
Kılıç, Önder | Belivermiş, Murat | Çotuk, Yavuz | Topçuoğlu, Sayhan
Radionuclides levels were determined in indigenous and transplanted mussels (Mytilus galloprovincialis) collected from Turkish marine environment. Radioactivity concentrations of 137Cs, 40K, 226Ra, 228Ra, 210Po and 210Pb were determined in the soft tissues of the mussel samples collected in Bosphorus Strait, Coasts of Black Sea, Marmara Sea and Aegean Sea. Mussel transplantation was carried out by using mussel cages in Levantine Sea coast since M. galloprovincialis did not naturally adapt along the coast. The average activity concentrations of 137Cs, 40K, 226Ra, 228Ra, 210Po and 210Pb in the coastline of Turkey were found to be 0.7±0.1, 469±24, 0.9±0.1, 1.0±0.1, 122±4 and 10.9±0.9Bqkg−1 in dry weight (dw), respectively. The average of 210Po/210Pb ratio was found to be ∼14. Total annual effective 210Po dose was calculated to be in the range of 0.25–3.30 μSv due to mussel consumption. Radioactivity and dose levels were compared with those of similar studies carried out in Mediterranean countries.
Показать больше [+] Меньше [-]