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Risk assessment of oil spills in the Chinese Bohai Sea for prevention and readiness 全文
2018
Yu, Fangjie | Xue, Songyuan | Zhao, Yang | Chen, Ge
Oil spill accidents occur with increasing frequency in the Chinese Bohai Sea because of the presence of extensive number of oil platforms and oil pipelines the Chinese Bohai region. An appropriate risk assessment for oil spill prevention and readiness is necessary. Risk assessment for the entire Chinese Bohai Sea based on a quantitative method is proposed. We created a hypothetical simulation of oil spill trajectories based on an oil spill model for 28 oil platforms in the Chinese Bohai region in 2010. Then, we mapped a risk index in the study areas based on a combination of oil spill trajectories and shoreline susceptibility data. Five high-risk areas were identified in the entire Chinese Bohai Sea. Detailed suggestions for prevention and readiness are described here. These results can help in developing a risk assessment of oil spills in the Chinese Bohai Sea and serve as a useful analytic tool for slick-related emergencies.
显示更多 [+] 显示较少 [-]Biomonitoring coastal environments with transplanted macroalgae: A methodological review 全文
2018
García-Seoane, R. | Aboal, J.R. | Boquete, M.T. | Fernández, J.A.
The use of macroalgae transplants is a recent technique used in pollution biomonitoring studies in marine ecosystems. Only 60 articles published between 1978 and 2017 reported the use of this environmental tool for the active biomonitoring of inorganic pollutants and nutrients worldwide. In this review paper, we evaluated studies on this topic in relation to the development of methodological aspects of the technique and the degree of standardization of the protocols used. On the basis of findings of this review, we conclude that the technique is not yet standardized and that uniformisation of protocols is required to enable comparison of the results of different studies. We propose a new protocol for applying the technique, in which each suggestion has been carefully and rigorously compared with the relevant findings reported in the available literature.
显示更多 [+] 显示较少 [-]Insights of the Removal Mechanisms of Pharmaceutical and Personal Care Products in Constructed Wetlands 全文
2018
Vo, Hoang-Nhat-Phong | Bui, Xuan-Thanh | Nguyen, Thi-Minh-Hong | Koottatep, T. | Bandyopadhyay, Amitava
PURPOSE OF REVIEW: Pharmaceutical and personal care products (PPCPs) are chemicals employed in human healthcare, veterinary, medical diagnosis, and cosmetics, which have increasingly polluted water sources. Extensive research has demonstrated constructed wetlands (CWs) technology as a low-cost but efficient approach for PPCPs removal. There has been a growing interest to better understand the degradation mechanisms of PPCPs in wetland cells. Data corroborated in this review show that these degradation mechanisms include photolytic degradation, adsorption, phytodegradation, and microbial degradation. Each of these degradation mechanisms performs differently in wetland cells. This review also highlights the lack of research works to quantify the contribution of these degradation mechanisms to the overall efficiency of CWs to remove PPCPs as a major bottleneck for further application of this technology. The ultimate goal is to apply and prioritize a suitable degradation mechanism for successfully eliminating corresponding PPCPs. This review, therefore, provides further insights to (i) elucidate the importance of these removal mechanisms, and (ii) quantify their contribution in overall PPCPs removal processes. This review aims to understand the importance and contribution of degradation mechanisms of PPCPs removal in constructed wetlands. RECENT FINDINGS: The degradation mechanisms of PPCPs in constructed wetlands depended on various conditions; yet, which factors are preferred? Furthermore, the number of research works, related to quantifying the contribution of degradation mechanisms, is limited. The hydrophobic/hydrophilic character, reflecting as log Kₒw (or log Dₒw), is the most commonly used. The photolytic degradation is appropriate with low and moderate hydrophobic values (log Dₒw from − 2.3 to 3). The role of adsorption is moderate, while it is more efficient with the higher hydrophobic compounds. The media is important for plant growth and micro-organism community development. The plant uptake is better for PPCPs with higher hydrophobicity (log Kₒw from 1 to 4). However, it is difficult to quantify their contribution and the number of related studies is limited.
显示更多 [+] 显示较少 [-]Release of PAHs and heavy metals in coastal environments linked to leisure boats 全文
2018
Egardt, Jenny | Mørk Larsen, Martin | Lassen, Pia | Dahllöf, Ingela
Release of PAHs and heavy metals in coastal environments linked to leisure boats 全文
2018
Egardt, Jenny | Mørk Larsen, Martin | Lassen, Pia | Dahllöf, Ingela
Leisure boats are responsible for elevated levels of heavy metals and PAHs in sediments in- and near marinas and natural harbours. As these compounds are released directly into the water column they also pose a threat to organisms in the pelagic environment.Passive samplers were deployed during peak and post tourist season in the water column of natural harbours, leisure boat waterways and small marinas to measure the dissolved fraction of PAHs and metal ions.Differences between seasons indicative of leisure boat activities were found as PAH composition differed between peak and post season for natural harbours and waterways, where heavier PAHs increased during peak season. During peak season, metal samplers were covered by biofouling, which likely affected the uptake. Post season metal concentrations differ between locations, with concentrations exceeding quality standards at near mainland locations where boats are maintained, compared to the sites in the archipelago.
显示更多 [+] 显示较少 [-]Impacts of recreational boating in coastal seascapes and implications for management 全文
2018
Egardt, Jenny
Kosterhavet National Park, a marine protected area on the Swedish west coast, is a popular destination for tourists and attracts over half a million visitors annually. Many of the tourists arrive by boat, and the natural harbours are frequently visited. Boat presence may affect bottom substrates through anchoring, and pollution could also occur in the form of leaching antifouling paints, fuel residue (PAHs) and litter. This thesis set out to investigate if there are any lingering impacts resulting from boat tourism in Kosterhavet and suggests management efforts in those cases there are. Through studies using a video sled, data from two consecutive years revealed visible anchor traces on soft unvegetated bottoms, and number of traces were also linked to number of bottom anchoring boats. Furthermore, it was found that visitors engage in bottom anchoring at locations where sensitive habitats like eelgrass and oyster beds are located, which may result in harm to both habitat types. Sediment samples taken in both natural harbours and small marinas unexpectedly showed presence of long since banned antifouling products like TBT, but also more recently prohibited biocides like irgarol and diuron. This suggests that they are still in use. Moreover, water samples from the area show that the currently used antifouling compound copper, is likely to exceed threshold values set by the Swedish Agency for Marine and Water Management (SwAM) during peak boat season. Concentrations of PAHs were found to be below threshold values for water, but they are also known to have low water solubility and are more likely to be bound to particles. From the video data, occurrence of seafloor litter was also obtained, and data on beach litter from reference sites on the Swedish west coast was downloaded from the OSPAR beach litter database. Seafloor litter, in contradiction to beach litter, was at a much higher degree found to have an origin related to recreational activities. This suggest that beach litter stem from other activities in the park, or are brought to the area by currents. A threat analysis based on the leisure boat related threats; anchoring, antifouling, PAHs and litter were performed. Threats were analysed with respect to their potential impact to the soft bottom values; eelgrass, oysters and blue mussels. The sum of these threats showed that eelgrass was highly impacted by anchoring, but oysters were more severely affected when all threats were considered. This type of threat analysis can be of great value to park managers, as they need to make prioritizations regarding how to use their often limited resources. Based on these finding, it is, among others, suggested that bottom anchoring should not be allowed at locations where eelgrass and oyster beds occur, and that bottom friendly mooring solutions should be made available to avoid negative impact on these habitats.
显示更多 [+] 显示较少 [-]Statistical models of fecal coliform levels in Pacific Northwest estuaries for improved shellfish harvest area closure decision making 全文
2018
Zimmer-Faust, Amity G. | Brown, Cheryl A. | Manderson, Alex
There is a substantial need for tools that effectively predict spatial and temporal fecal pollution patterns in estuarine waters. In this study, statistical models of exceedances of shellfish fecal coliform (FC) water quality criteria were developed using a 10-year dataset of FC levels and environmental data. Performance (sensitivity, specificity, and predictive capacity) of five different types of models was tested (MLR regression, Tobit (censored) regression, Firth's binary logistic regression (BLR), classification trees, and mixed-effects regression) for each of three conditionally managed shellfish-harvesting areas in Tillamook Bay, Oregon (USA). The most influential variables were related to precipitation and river stage height in the wet season and wind and tidal-stage in the dry season. Classification tree and Firth's BLR approaches better explained exceedances of shellfish water quality standards than the current closure thresholds. Findings demonstrate the utility of statistical modeling approaches for improved management of shellfish harvesting waters.
显示更多 [+] 显示较少 [-]Occurrence and virulence of Vibrio parahaemolyticus isolated from seawater and bivalve shellfish of the Gyeongnam coast, Korea, in 2004–2016 全文
2018
Park, Kunbawui | Mok, Jong Soo | Ryu, A Ra | Kwon, Ji Young | Ham, In Tae | Shim, Kil Bo
We determined the abundance and virulence of Vibrio parahaemolyticus in seawater and bivalves from the Gyeongnam coast in Korea, a major area for the seafood industry, during 2004–2016. V. parahaemolyticus is one of the most common pathogen causing seafood-borne illnesses in Korea, and increases during the summer. Its occurrence in seawater and bivalve samples was seasonally dependent, with high levels during the summer to early autumn. There were more strains in the area of sea continually exposed to inland wastewater. Only 5.1% and 3.5% of V. parahaemolyticus isolates from seawater and bivalves, respectively, had the trh gene, and only the bivalve isolates produced the tdh gene at levels below 2%. Continuous monitoring is clearly needed to reduce seafood-borne outbreaks of disease caused by V. parahaemolyticus, and to reveal the occurrence patterns and the presence of toxic genes of the strains in different marine environments.
显示更多 [+] 显示较少 [-]Impact of anthropogenic activities on mussel (Mytella guyanensis) in the Gulf of Paria, Trinidad 全文
2018
Balgobin, Aaron | Ramroop Singh, Natasha
This body of work demonstrated the levels of selected contaminants (as well as their potential sources), in mussels (Mytella guyanensis) - a known bio-indicator of pollution, along the west coast (Gulf-of-Paria) of Trinidad. The findings demonstrated that polyaromatic hydrocarbons levels in the mussels investigated were moderate to high (201.80–1200.08 μg/kg). Notably, benzo(a)pyrene levels (1.15–9.32 μg/kg) exceeded the European Union guidelines at various sites. The distribution of PAHs and trace elements in the Gulf of Paria are impacted by tidal currents and local source discharge. Significant risks were identified from toxic carcinogenic equivalent levels (3.01 to 22.37 μg/kg) and mutagenic equivalent levels (3.98 to 38.61 μg/kg). The concentration of trace elements, Zn (46.05–56.36 mg/kg) and Cd (0.46–1.17 mg/kg), exceeded both local and international guidelines at certain sites investigated. The analysis revealed a high bioavailability of the identified pollutants in the Gulf of Paria from industrial, urban and marine activities.
显示更多 [+] 显示较少 [-]Synthetic lipids as a biocide candidate for disinfection of ballast water 全文
2018
Batista, William R. | Fernandes, Flavio C. | Neves, Maria H.C.B. | Nascimento, Thiana S. | Lopes, Rosangela S.C. | Lopes, Claudio C. | Ziegler, Gregory P. | Soler-Figueroa, Brenda M. | Sparks, Darrick | Fontaine, Diana N. | Carney, Katharine J. | Quiñones-Oquendo, Luz E. | Ruiz, Gregory M.
The objective of this study is to propose the use of specific synthetic lipid as an active substance (biocide) in the control of harmful aquatic microorganisms, such as pathogens and non-indigenous species, transported in ships' ballast water. The biocide candidate, without metal or halogen components, was produced from a sub-product of the edible oil industry, the lecithin. Laboratory assays were conducted with phytoplankton, zooplankton, and marine bacteria to evaluate the efficiency of the biocide. The study also considers specific biocide's characteristics related to environmental risks, such as chemical composition, persistence, bioaccumulation, and toxicity. Results showed that, in the first 24 h of treatment, the biocide effectively reduced the concentration of the planktonic micro-organisms to very low levels. Additionally, a preliminary risk evaluation pointed that biocide candidate has a low residual toxicity, also a low potential for persistence and bioaccumulation in the environment.
显示更多 [+] 显示较少 [-]Changes to polychlorinated biphenyl (PCB) signatures and enantiomer fractions across different tissue types in Guillemots 全文
2018
Megson, David | Brown, Thomas A. | O'Sullivan, Gwen | Robson, Matthew | Ortiz, Xavier | Worsfold, Paul J. | Comber, Sean | Lohan, Maeve C. | Reiner, Eric J.
Two Guillemot carcases were dissected, each providing 12 discrete tissue samples and 3 samples of partially digested food. One hundred and five PCBs from the 209 PCBs determined by GCxGC-ToFMS were detected. The relative proportions of individual PCBs did not vary greatly within tissue types, although the PCB profile from undigested food could be distinguished. Enantiomer fractions (EFs) were determined for CB-95, CB-136 and CB-149 by GC-HRqToFMS. EFs in the partially digested food were near racemic, with high levels of enrichment for E1 CB-95 in the kidneys and liver (EF of 0.80 and 0.84 respectively). This provides some of the clearest evidence to date that fractionation takes place in the organs where metabolic biotransformation and elimination of PCBs occurs. Our findings also confirm the ability of non-lethal sampling techniques, such as collection of small (<1 g) blood samples, to provide PCB signatures that are representative of an individual organism.
显示更多 [+] 显示较少 [-]Evaluating the impact of sewage discharges on the marine environment with a lightweight AUV 全文
2018
Bonin-Font, Francisco | Lalucat, Jordi | Oliver-Codina, Gabriel | Massot-Campos, Miquel | Font, Eric Guerrero | Carrasco, Pep Lluis Negre
Environmental studies that use small Autonomous Underwater Vehicles (AUVs) can survey wider and deeper areas, compared to traditional methods, at a reasonable cost. Thanks to the precise vehicle navigation systems, the data collected can be accurately geolocalized. Besides, lightweight vehicles can be deployed from the shore or from small boats and programmed by means of user-friendly graphical interfaces, thus reducing and simplifying the need of human resources and infrastructures. Based on such a technology, this paper presents a framework to assess the environmental impact of a marine sewage outfall set in the Bay of Palma (Mallorca, Spain). We report the results of the analysis of the images recorded in the course of six missions conducted with an AUV. The plan was designed after a microbiological analysis detected the presence of cyanobacteria in a sample of sand and water collected by scuba divers close to the sewer pipe mouth.
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