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Mapping widespread and increasing underwater noise pollution from acoustic deterrent devices Texte intégral
2018
Findlay, C.R. | Ripple, H.D. | Coomber, F. | Froud, K. | Harries, O. | van Geel, N.C.F. | Calderan, S.V. | Benjamins, S. | Risch, D. | Wilson, B.
Acoustic deterrent devices (ADDs) are used in attempts to mitigate pinniped depredation on aquaculture sites through the emission of loud and pervasive noise. This study quantified spatio-temporal changes in underwater ADD noise detections along western Scotland over 11 years. Acoustic point data (‘listening events’) collected during cetacean line-transect surveys were used to map ADD presence between 2006 and 2016. A total of 19,601 listening events occurred along the Scottish west coast, and ADD presence was recorded during 1371 listening events. Results indicated a steady increase in ADD detections from 2006 (0.05%) to 2016 (6.8%), with the highest number of detections in 2013 (12.6%), as well as substantial geographic expansion. This study demonstrates that ADDs are a significant and chronic source of underwater noise on the Scottish west coast with potential adverse impacts on target (pinniped) and non-target (e.g. cetaceans) species, which requires further study and improved monitoring and regulatory strategies.
Afficher plus [+] Moins [-]Effects of temperature and salinity on Ruppia sinensis seed germination, seedling establishment, and seedling growth Texte intégral
2018
Gu, Ruiting | Zhou, Yi | Song, Xiaoyue | Xu, Shaochun | Zhang, Xiaomei | Lin, Haiying | Xu, Shuai | Zhu, Shuyu
As typical submerged aquatic vegetation, Ruppia species are facing population reductions due to anthropogenic impacts. In this study, we investigated the effects of temperature and salinity on seed germination and seedling establishment of Ruppia sinensis seeds collected from northern China. The effects of seven salinities (0–50) and six water temperatures (0–30°C) on seed germination were investigated to identify the environmental conditions that could potentially limit survival and growth. We found that: 1) optimum seed germination was salinity 5 at 30°C; 2) high salinity (salinity 40–50) and low temperature (0°C) significantly inhibited seed germination; 3) seed germination with increasing temperature showed a bimodal pattern at suitable salinities (5–10); 4) storing seeds at high salinities (40–50) or low temperature (0°C) promoted germination after transferal to optimal germination conditions. These findings may serve as useful information for R. sinensis habitat establishment and restoration programs.
Afficher plus [+] Moins [-]Radioactive cesium concentrations in coastal suspended matter after the Fukushima nuclear accident Texte intégral
2018
Kubo, Atsushi | Tanabe, Kai | Suzuki, Genta | Itō, Yukari | Ishimaru, Takashi | Kasamatsu-Takasawa, Nobue | Tsumune, Daisuke | Mizuno, Takuji | Watanabe, Yutaka W. | Arakawa, Hisayuki | Kanda, Jota
Radioactive cesium concentrations in the suspended matter of the coastal waters around the Fukushima Daiichi Nuclear Power Plant (FDNPP) were investigated between January 2014 and August 2015. The concentrations of radioactive cesium in the suspended matter were two orders higher in magnitude than those determined in the sediment. In addition, we discovered highly radioactive Cs particles in the suspended matter using autoradiography. The geometrical average radioactivity of particles was estimated to be 0.6 Bq at maximum and 0.2 Bq on average. The contribution ratio of highly radioactive Cs particles to each sample ranged from 13 to 54%, and was 36% on average. A major part of the radioactive Cs concentration in the suspended matter around the FDNPP was strongly influenced by the highly radioactive particles. The subsequent resuspension of highly radioactive Cs particles has been suggested as a possible reason for the delay in radioactive Cs depuration from benthic biota.
Afficher plus [+] Moins [-]Assessing the effectiveness of surrogates for species over time: Evidence from decadal monitoring of a Mediterranean transitional water ecosystem Texte intégral
2018
Bevilacqua, S. | Mistri, M. | Terlizzi, A. | Munari, C.
The use of higher taxa or alternative approach to species surrogacy, such as the BestAgg procedure, could represent cost-effective solutions to avoid expensive species-level identifications in monitoring activities, especially on the long term. However, whether a set of surrogates would be effective in subsequent reiteration of the same assessment remains largely unsolved. We used a long-term dataset on macro-benthic assemblages to test the hypothesis that family-level and BestAgg surrogates which are effective for a limited period of monitoring could be successfully applied to quantify community patterns also in subsequent monitoring programmes. The effectiveness of surrogates in detecting temporal variations in assemblage structure as at species level remained basically unaffected over a decade. Recognizing once and for all if species surrogacy may have a practical value for monitoring will strongly depend on future assessments of the potential of surrogates to reflect community changes and to retain this prerogative over time.
Afficher plus [+] Moins [-]Modeling atmospheric volatile organic compound concentrations resulting from a deepwater oil well blowout – Mitigation by subsea dispersant injection Texte intégral
2018
Crowley, Deborah | French-McCay, Deborah | Santos, L. (Lynne) | Chowdhury, Biswanath | Markussen, Robin
The atmospheric concentrations of volatile organic compounds (VOCs) generated by surface slicks during an oil spill have not been extensively studied. We modeled oil transport and fate, air emissions, and atmospheric dispersion of VOCs from a hypothetical deepwater well blowout in De Soto Canyon of the Gulf of Mexico assuming no intervention and use of SubSea Dispersant Injection (SSDI) at the source during three week-long periods representing different atmospheric mixing conditions. Spatially varying time histories of atmospheric VOCs within ~2 km from the release site were estimated. As compared to the no-intervention case, SSDI dispersed the discharged oil over a larger water volume at depth and enhanced VOC dissolution and biodegradation, thereby reducing both the total mass of VOCs released to the atmosphere and the concentration of VOCs within 2 km from the release site. Atmospheric conditions also influenced the VOC concentrations, although to a lesser degree than SSDI.
Afficher plus [+] Moins [-]Taiwan's legal framework for marine pollution control and responses to marine oil spills and its implementation on T.S. Taipei cargo shipwreck salvage Texte intégral
2018
Fan, Chihhao | Hsu, Cheng-Jui | Lin, Jia-Yu | Kuan, Yung-Kai | Yang, Chieh-Chung | Liu, Ruixiang | Yeh, Jiunn-Horng
Many shipwreck events occur in the neighboring areas of Taiwan due to the volume of maritime traffic and geographical conditions around Taiwan. The oil spills from such events can be devastating for the surrounding sea and coastal areas. The government realized the importance of marine pollution prevention and enforced the Marine Pollution Control Act and the Major Marine Oil Pollution Emergency Response Plan to mitigate the impact of oil spill pollution. The T.S. Taipei shipwreck highlighted the effectiveness of the national marine pollution prevention system. Inter-departmental cooperation and collaboration with private sectors are the keys for effective response. This article is the first detailed documentation of an oil spill response for a maritime incident from the beginning to the final termination of shipwreck removal. It shows the people in Taiwan intend to collaborate with other states to make a significant contribution to marine environment conservation and sustainability.
Afficher plus [+] Moins [-]Biomarkers of physiological responses of Octopus vulgaris to different coastal environments in the western Mediterranean Sea Texte intégral
2018
Sillero-Ríos, J. | Sureda, A. | Capó, X. | Oliver-Codorniú, M. | Arechavala-Lopez, P.
The increase of pollutants in coastal seawater could produce several harmful biological effects on marine organisms related to the production of reactive oxygen species (ROS) causing cellular and tissue damages through oxidative stress mechanisms. Common octopuses (Octopus vulgaris) inhabiting coastal areas under high anthropogenic activity of Mallorca (W-Mediterranean Sea) have the ability to control oxidative damage by triggering antioxidant enzyme responses. Analyzing the digestive glands, octopuses from human-altered coastal areas showed higher activity of superoxide dismutase (SOD), catalase (CAT) and glutathione S-transferase (GST) compared to octopuses from non-influenced coastal waters (i.e. marine reserve area). Higher metallothionein (MT) concentrations and lack of malondialdehyde (MDA) variations also reflect adaptations of O. vulgaris to polluted areas. This is the first study assessing the levels of the oxidative stress biomarkers on O. vulgaris in the Mediterranean Sea, revealing their usefulness to assess diverse environmental pollution effects on this relevant ecological and commercial species.
Afficher plus [+] Moins [-]Threat of plastic ageing in marine environment. Adsorption/desorption of micropollutants Texte intégral
2018
Kedzierski, Mikaël | D'Almeida, Mélanie | Magueresse, Anthony | Le Grand, Adélaïde | Duval, Hélène | César, Guy | Sire, Olivier | Bruzaud, Stéphane | Le Tilly, Véronique
Ageing of various plastics in marine environment was monitored after immersion of two synthetic (polyvinylchloride, PVC, and polyethylene terephthalate, PET) and one biodegradable (poly(butylene adipate co-terephtalate), PBAT) plastics for 502days in the bay of Lorient (Brittany, France). Data analysis indicates that aged PVC rapidly releases estrogenic compounds in seawater with a later adsorption of heavy metals; PET undergoes a low weakening of the surface whereas no estrogenic activity is detected; PBAT ages faster in marine environment than PVC. Aged PBAT exhibits heterogeneous surface with some cavities likely containing clay minerals from the chlorite group. Besides, this degraded material occasionally shows a high estrogenic activity. Overall, this study reports, for the first time, that some aged plastics, without being cytotoxic, can release estrogenic compounds in marine environment.
Afficher plus [+] Moins [-]High zinc exposure leads to reduced dimethylsulfoniopropionate (DMSP) levels in both the host and endosymbionts of the reef-building coral Acropora aspera Texte intégral
2018
Deschaseaux, Elisabeth | Hardefeldt, Jannah | Jones, Graham | Reichelt-Brushett, Amanda
Dimethylsulfoniopropionate (DMSP) is a biogenic compound that could be involved in metal detoxification in both the host and endosymbionts of symbiotic corals. Acropora aspera, a common reef-building coral of the Great Barrier Reef, was exposed to zinc doses from 10 to 1000μg/L over 96h, with zinc being a low-toxic trace metal commonly used in the shipping industry. Over time, significantly lower DMSP concentrations relative to the control were found in both the host and symbionts in the highest zinc treatment where zinc uptake by both partners of the symbiosis was the highest. This clearly indicates that DMSP was consumed or stopped being produced under high and extended zinc exposure. This drop in DMSP was first observed in the host tissue, suggesting that the coral host was the first to respond to metal contamination. Such decrease in DMSP concentrations could influence the long-term health of corals under zinc exposure.
Afficher plus [+] Moins [-]Distribution characteristics, sources, and ecological risk assessment of polycyclic aromatic hydrocarbons in sediments from the Qinhuangdao coastal wetland, China Texte intégral
2018
Lin, Faxiang | Han, Bin | Ding, Yu | Li, Qian | Gao, Wei | Zheng, Li
Sixteen USEPA priority polycyclic aromatic hydrocarbons (PAHs) were analyzed by gas chromatography–mass spectrometry. Twenty-three samples were collected from the surface sediments of Qinhuangdao coastal wetlands in this survey. This research aimed to identify the PAHs contamination level, composition pattern, pollution sources, and assess the ecological risk of PAHs. The results showed that the sum of PAH concentrations ranged from 341.61ng/g to 4703.80ng/g (mean: 1367.80ng/g), which is higher than the reported values for different wetlands worldwide. Five- and four-ring PAHs (34.08% and 32.97% of Ʃ16PAHs, severally) were predominant in the wetland sediment. The PAH source distribution in the surface sediments was determined using diagnostic ratio and PCA/MLR. Consequently, multiple PAH sources were found. Of the total PAHs, 70.01% was derived from vehicular emission, 25.73% from coke oven, and 4.26% from petroleum-based product spills. The effect range low/effect range median (ERL/ERM) values indicated a low toxicity risk level. However, the DBahA concentrations exceeded the ERL level, and even the ERM level, in some stations. The mean effects range–median quotient (M-ERM-Q) suggests a low ecological risk for the PAHs, but a medium risk for some stations in the coastal wetland sediments.
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