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The short-term effects of farmed fish food consumed by wild fish congregating outside the farms 全文
2017
Gonzalez-Silvera, D. | Guardiola, F.A. | Cordero, H. | Cuesta, A. | Esteban, M.A. | Martínez-López, F.J. | López-Jiménez, J.A.
The short-term effects of farmed fish food consumed by wild fish congregating outside the farms 全文
2017
Gonzalez-Silvera, D. | Guardiola, F.A. | Cordero, H. | Cuesta, A. | Esteban, M.A. | Martínez-López, F.J. | López-Jiménez, J.A.
We simulated in the laboratory the possible effects on fatty acids and immune status of wild fish arriving for the first time in the vicinity of a sea-cage fish farm, shifting their natural diet to commercial feed consumption, rich in fatty acids of vegetable origin. The flesh fatty acid profile of golden mullet specimens was altered after 2weeks of commercial feed consumption, showing an increase in fatty acids of vegetable origin. The serum peroxidase and bactericidal activities, and head-kidney leucocyte phagocytic capacity, increased after eight weeks of the new diet, while the respiratory burst activity decreased. The extent of these changes cannot be considered large enough to regard them as compromising the health status of fish. More research is needed in order to elucidate whether the rapid assimilation of the dietary fatty acids could harm the immune status of fish when feeding for longer periods than two months.
显示更多 [+] 显示较少 [-]The short-term effects of farmed fish food consumed by wild fish congregating outside the farms 全文
2017 | 2016
Gonzalez-Silvera, D. | Guardiola Abellán, Francisco Antonio | Cordero, H. | Cuesta Peñafiel, Alberto | Esteban Abad, María Ángeles | Martínez-López, F.J. | López-Jiménez, J.A. | Facultades, Departamentos, Servicios y Escuelas::Departamentos de la UMU::Fisiología
We simulated in the laboratory the possible effects on fatty acids and immune status of wild fish arriving for the first time in the vicinity of a sea-cage fish farm, shifting their natural diet to commercial feed consumption, rich in fatty acids of vegetable origin. The flesh fatty acid profile of golden mullet specimens was altered after 2 weeks of commercial feed consumption, showing an increase in fatty acids of vegetable origin. The serum peroxidase and bactericidal activities, and head-kidney leucocyte phagocytic capacity, increased after eight weeks of the new diet, while the respiratory burst activity decreased. The extent of these changes cannot be considered large enough to regard them as compromising the health status of fish. More research is needed in order to elucidate whether the rapid assimilation of the dietary fatty acids could harm the immune status of fish when feeding for longer periods than two months.
显示更多 [+] 显示较少 [-]The estimation for ballast water discharged to China from 2007 to 2014 全文
2017
Zhang, Xiaofang | Bai, Mindong | Tian, Yiping | Du, Huan | Zhang, Zhitao
Ballast water has been identified as one of the main causes for worldwide transfer of non-indigenous marine species. The volume and source of ballast water are the fundamental elements for an evaluation of the risk posed. However, it is difficult to obtain the volume of ballast water discharged to China, because of the absence of information platform, and until now there is no public report. In this paper, the total volume of ballast water discharged to China and Chinese five major port-groups were estimated. Results showed: the total volume of ballast water exhibited a trend of slow increase from 2007 to 2014, and reached 311 million tons in 2014. Yangtze River Delta received the highest volume of ballast water among all port-groups. The information provided in this research may play an important role in helping policy decision-makers manage such coastal discharges.
显示更多 [+] 显示较少 [-]Assessment of nutrient and heavy metal contamination in the seawater and sediment of Yalujiang Estuary 全文
2017
Li, Hongjun | Lin, Lin | Ye, Sheng | Li, Hongbo | Fan, Jingfeng
Yalujiang River is a famous border river between China and North Korea. In this study, 22 sample sites (seawater and sediments) were investigated to determine the concentrations of nutrients (dissolved inorganic nitrogen and soluble reactive phosphorus) and trace elements (Hg, As, Pb, Cu, Cd, Cr, and Zn) during the flood season (August). Generally, the concentration of nutrients were higher in the entrance of the estuary than that in the downstream region and the trophic index ranged from moderate to high production, indicating a potential eutrophication risk. With the exception of Cd, the mean concentrations of most metals attained the first level of seawater quality. Sediment pollution assessment was undertaken using contamination factor (CF) and geoaccumulation index (Igeo). The CF values of the seven trace elements were in the following order: Cd>Hg>Pb>As>Cu>Zn>Cr. Both CF and Igeo values indicated the elevated Cd and Hg concentrations in the region. Cluster analysis indicated that the sources of Cu, Cd, Cr, and Zn were mainly derived from copper mine and coastal industrial effluents, whereas Pb, Hg, and As were mainly from vehicle emissions and oil combustion. This study could provide a basis for the sustainable management of the marine ecosystem in this region.
显示更多 [+] 显示较少 [-]Micro- and mesoplastics in Northeast Levantine coast of Turkey: The preliminary results from surface samples 全文
2017
Gündoğdu, Sedat | Çevik, Cem
The determination of the microplastic distribution will be beneficial as a measure of the potential effects on the environment. The Mediterranean Sea had a high risk of pollution as it was enclosed by highly populated and industrialized countries. Here, we determined the level of micro- and mesoplastic pollution in Iskenderun and Mersin Bays, located in the Northeastern Levantine coast of Turkey. The average level of both micro- and mesoplastic was determined to be 0.376 item/m2 at seven stations. The highest level was determined in Mersin Bay at the mouth of the Seyhan river (Station no. 7, with 906 items), and the lowest level was found in Station no. 4 in Iskenderun Bay (78 items). As a result of this study, it was determined that the microplastic pollution level in the Mediterranean coast of Turkey was similar to the other regions of the Mediterranean Sea.
显示更多 [+] 显示较少 [-]Distribution, sources and toxicity potential of hydrocarbons in harbor sediments: A regional assessment in SE Brazil 全文
2017
Pinheiro, Pedro P.O. | Massone, Carlos G. | Carreira, Renato S.
Aliphatic and polycyclic aromatic hydrocarbons (PAHs) were quantified in harbors sediments from SE Brazil. The aims were to (i) compare harbors with distinct sizes and under the influence of different environmental pressures with respect to the sources and level of hydrocarbon contamination and (ii) evaluate the potential of adverse biological effects of sediment contamination by PAHs, based on sediment quality guidelines and toxicity equivalence quotient. The concentrations of total aliphatics (39.9μgg−1; 22.9–113μgg−1) and total PAHs (727ngg−1; 366–1760ngg−1) varied according to the size of and urban development around each harbor. Mixed contamination by petrogenic and pyrolytic hydrocarbons, and input of biogenic compounds, indicated the influence of both harbor activities and a myriad of urban, industrial and atmospheric inputs. The quality of sediment poses a risk to benthic biological communities, and, if dredged, this material may cause environmental damage in the waste disposal area.
显示更多 [+] 显示较少 [-]Calculating in situ degradation rates of hydrocarbon compounds in deep waters of the Gulf of Mexico 全文
2017
Thessen, Anne E. | North, Elizabeth W.
Biodegradation is an important process for hydrocarbon weathering that influences its fate and transport, yet little is known about in situ biodegradation rates of specific hydrocarbon compounds in the deep ocean. Using data collected in the Gulf of Mexico below 700m during and after the Deepwater Horizon oil spill, we calculated first-order degradation rate constants for 49 hydrocarbons and inferred degradation rate constants for an additional 5 data-deficient hydrocarbons. Resulting calculated (not inferred) half-lives of the hydrocarbons ranged from 0.4 to 36.5days. The fastest degrading hydrocarbons were toluene (k=−1.716), methylcyclohexane (k=−1.538), benzene (k=−1.333), and C1-naphthalene (k=−1.305). The slowest degrading hydrocarbons were the large straight-chain alkanes, C-26 through C-33 (k=−0.0494 through k=−0.007). Ratios of C-18 to phytane supported the hypothesis that the primary means of degradation in the subsurface was microbial biodegradation. These degradation rate constants can be used to improve models describing the fate and transport of hydrocarbons in the event of an accidental deep ocean oil spill.
显示更多 [+] 显示较少 [-]Seasonal variability of different biomarkers in mussels (Mytilus galloprovincialis) farmed at different sites of the Gulf of La Spezia, Ligurian sea, Italy 全文
2017
Balbi, Teresa | Fabbri, Rita | Montagna, Michele | Camisassi, Giulia | Canesi, Laura
Mussels (Mytilus spp.) are worldwide utilized in marine biomonitoring by a multi-biomarker approach. However, for a correct interpretation of different biomarker responses, information is needed on their natural seasonal variability due to environmental/physiological factors.In this work, the seasonal variations of different biomarkers were investigated in M. galloprovincialis from 4 different sites from the gulf of La Spezia (Ligurian sea, Italy), an intensive rearing area in the north-western Mediterranean near La Spezia harbor, an important commercial and touristic port. Lysosomal membrane stability-LMS, stress on stress-SoS, phagocytosis, tissue metallothionein-MT content, oxidative stress related enzyme activities (GST, catalase), and nitric oxide (NO) production were evaluated. The results underline the importance of LMS and SoS as core descriptors of the mussel health status in relation to seasonal variations in temperature and reproduction. These data represent the baseline information for ongoing biomonitoring studies related to dredging activities in this area.
显示更多 [+] 显示较少 [-]Heavy metal bioaccumulation in mangrove ecosystem at the coral triangle ecoregion, Southeast Sulawesi, Indonesia 全文
2017
Analuddin, Kangkuso | Sharma, Sahadev | Jamili, | Septiana, Andi | Sahidin, Idin | Rianse, Usman | Nadaoka, Kazuo
This study aimed to determine the role of mangroves as a biofilter of heavy metals. The concentrations of heavy metals, namely copper, mercury, cadmium, zinc, and lead, in the mangroves Rhizophora apiculata, Ceriops tagal, Bruguiera gymnorrhiza, Lumnitzera racemosa, Xylocarpus granatum, Sonneratia alba, and Bruguiera parviflora at RAWN Park were determined using a Flame atomic absorption spectrophotometer. High concentrations of Cu (83.85μgg−1) and Hg (0.52μgg−1) were found in the tissues of L. racemosa, while high concentrations of Cd (10.81μgg−1), Zn (70.41μgg−1), and Pb (1.36μgg−1) were found in the tissues of B. gymnorrhiza, B. parviflora and C. tagal, respectively. The translocation and bioaccumulation factors of heavy metals by mangroves showed a variety of trends, which indicated the different partitioning and uptake capability of heavy metals in the tissues of various mangrove species. Thus, maintaining high diversity of mangroves is crucial to ensure the health and productivity of coastal zones.
显示更多 [+] 显示较少 [-]Feasibility of potable water generators to meet vessel numeric ballast water discharge limits 全文
2017
Albert, Ryan J. | Viveiros, Edward | Falatko, Debra S. | Tamburri, Mario N.
Ballast water is taken on-board vessels into ballast water tanks to maintain vessel draft, buoyancy, and stability. Unmanaged ballast water contains aquatic organisms that, when transported and discharged to non-native waters, may establish as invasive species. Technologies capable of achieving regulatory limits designed to decrease the likelihood of invasion include onboard ballast water management systems. However, to date, the treatment development and manufacturing marketplace is limited to large vessels with substantial ballast requirements. For smaller vessels or vessels with reduced ballast requirements, we evaluated the feasibility of meeting the discharge limits by generating ballast water using onboard potable water generators. Case studies and parametric analyses demonstrated the architectural feasibility of installing potable water generators onboard actual vessels with minimal impacts for most vessel types evaluated. Furthermore, land-based testing of a potable water generator demonstrated capability to meet current numeric discharge limits for living organisms in all size classes.
显示更多 [+] 显示较少 [-]Characterization of organic compounds in winter PM1 aerosols in a small industrial town 全文
2017
Křůmal, K. | Mikuška, P. | Večeřa, Z.
PM1 aerosol, collected during winter campaign in urban area situated close to a large automobile factory, was analysed on content of selected organic compounds, namely monosaccharide anhydrides, diterpenoids (including retene and resin acids), n-alkanes (including pristane and phytane), polycyclic aromatic hydrocarbons (including picene), monosaccharides, disaccharides, polyols, hopanes and steranes.Monosaccharide anhydrides (MAs, markers for biomass burning) were the most abundant organic compounds (the mean sum of concentration of 513 ng m−3). The sum of MAs constituted in average 70.0% of the mass of all analysed organic compounds and 1.91% of the PM1 mass. Diterpenoids, markers for softwood combustion, were the second most abundant analysed organic compounds (the mean concentration of 119 ng m−3). The mean concentrations of other studied organic compounds were smaller, namely saccharides 31.6 ng m−3, n-alkanes, including isoprenoids 35.3 ng m−3, PAHs 15.6 ng m−3 and hopanes, including one sterane 1.54 ng m−3.Combustion of solid fuels (coal and wood) for household heating was the dominant emission source of carbonaceous aerosols sampled during the campaign. The composition of aerosols collected in the studied locality was affected by local emissions and also by regional transport of polluted air from small villages nearby Mladá Boleslav.Two unit risks (WHO and CalEPA) were applied for the estimation of carcinogenic risk of PAHs exposure. The computed lifetime cancer risk at the studied locality during the campaign period was 1.93 × 10−4 (WHO unit risk) and 2.43 × 10−6 (CalEPA unit risk) on average. However, the real cancer risk for the lifetime exposure (70 years) is lower at the studied locality because our measurement lasted only 2 weeks in winter when the concentrations of PAHs were higher than in other seasons of the year.
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