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Occurrence of microplastics in the coastal marine environment: First observation on sediment of China
2015
Qiu, Qiongxuan | Peng, Jinping | Yu, Xubiao | Chen, Fangchaizi | Wang, Jundong | Dong, Fenqiang
Microplastics in sediments from the Beibu Gulf and the coastline of China Sea were investigated to evaluate the occurrence and abundance of microplastics in China for the first time. Microplastics (<5mm) were taken from sediments by a flotation method. The number of microplastics was counted by a fluorescence microscope, an instrument that is rarely used in the detection of microplastics in sediments. This instrument led to results that were satisfactory. Compared with other sampled areas, microplastics were found in massive concentrations in China. Four types of microplastics, HDPE, PET, PE and PS, were identified. The results will provide useful background information for further investigations.
显示更多 [+] 显示较少 [-]Histopathology and contaminant concentrations in fish from Kuwait’s marine environment
2015
Al-Zaidan, A.S. | Al-Sarawi, H.A. | Massoud, M.S. | Al-Enezi, M. | Smith, A.J. | Bignell, J.P. | Green, M.J. | Askem, C. | Bolam, T.P.C. | Barber, J.L. | Bersuder, P. | Lyons, B.P.
Kuwait has witnessed major socioeconomic and industrial development in recent decades. Consequently, a variety of contaminants related to these activities have been discharged directly into the marine environment. This paper describes the application of a histopathology baseline survey in two potential sentinel species, the Giant sea catfish (Arius thalassinus) and the Fourlined terapon (Pelates quadrilineatus) to assess the health of biota inhabiting Kuwait’s marine environment. Histological analysis revealed several lesion types in both species, although the prevalence was generally considered low with no discernible differences between sampling locations. The analysis of contaminant burdens (metals, PCBs, PBDEs, HBCDD) in A. thalassinus, along with the analysis of bile for PAH metabolites in both species, indicated that levels of contaminant exposure was low. Overall the data show that both species appear to be susceptible to pathologies associated with environmental contaminants and therefore suitable for further investigation as sentinel organisms for biological effects monitoring.
显示更多 [+] 显示较少 [-]A review of the status and development of Kuwait’s fisheries
2015
Al-Husaini, M. | Bishop, J.M. | Al-Foudari, H.M. | Al-Baz, A.F.
The status of Kuwait’s fisheries landings and relative abundance for major species was reviewed using research data from Kuwait Institute for Scientific Research and landing data from the Kuwait’s Central Statistical Bureau. Landing data showed significant decreases for major commercial species such as zobaidy (Pampus argenteus), suboor (Tenualosa ilisha), hamoor (Epinephelus coioides), newaiby (Otolithes ruber) and hamra (Lutjanus malabaricus) while abundance data for the shrimp Penaeus semisulcatus showed significant reduction in the recent years mainly because of overfishing. The catch-rate data showed continuous decline for major species such as zobaidy, newaiby and hamoor, which indicate that stock abundances of these species are low. The reduction in stock abundance in context with changes in habitat quality, particularly the effects of reduced discharge of the Shatt Al-Arab, is discussed.
显示更多 [+] 显示较少 [-]Impact of industrial effluents on geochemical association of metals within intertidal sediments of a creek
2015
Volvoikar, Samida P. | Nayak, G.N.
Metal speciation studies were carried out on three intertidal core sediments of the industrially impacted Dudh creek located along west coast of India. Metals indicated a drastic increase in the bioavailable fraction towards the surface of the cores, suggesting an increase in anthropogenic metal input in recent years as compared to the past. Also, when compared with Vaitarna estuary and Khonda creek of Thane district, the speciation of metals in Dudh creek sediments was observed to have been highly modified in recent years. High concentrations of metals associated with bioavailable fractions therefore suggested a risk of toxicity to sediment associated biota of Dudh creek.
显示更多 [+] 显示较少 [-]Trace metals in the surface sediments of the eastern continental shelf of Hainan Island: Sources and contamination
2015
Xu, Fangjian | Tian, Xu | Yin, Xuebo | Yan, Huimei | Yin, Feng | Liu, Zhaoqing
Major (Al) and trace metal (Cu, Pb, Zn, Cr, Ni, Cd, and As) concentrations in 29 surface sediment samples from the eastern continental shelf of Hainan Island were evaluated to determine the level of contamination. A multivariate analysis indicated that the sources of Cd, As, and Pb were primarily anthropogenic, whereas the sources of Cu, Zn, Cr, and Ni were primarily natural and/or partially anthropogenic. Enrichment factor (EF) and geoaccumulation index (Igeo) values were calculated to assess the anthropogenic contamination in the region. Both the EF and Igeo values indicated relatively elevated Cd and As concentrations. This study provides a useful aid for sustainable marine management in the region.
显示更多 [+] 显示较少 [-]Optimization of elutriation device for filtration of microplastic particles from sediment
2015
Zhu, X.
The increasing presence of plastic pollution in marine ecosystems has become a major concern. In the environment, plastics break down into smaller and smaller pieces of microplastics. Methods of microplastic recovery are needed to reduce the dangers they can pose to a variety of organisms. An elutriation device was manufactured and optimized to achieve maximum microplastic recovery. The parameters flow rate and diameter of elutriation column were varied and their domain of variation was determined. A composite factorial experimental design was generated using MODDE 10.1 and was undergone. The optimal values of flow rate and column diameter were determined to be 385Lh−1 and 5.06cm respectively, under constraints, to achieve a maximum feasible microplastics recovery percentage of 50.2%. The elutriation process can be improved through further testing, and can be tested in the field to compare its efficiency to that of manual microplastics filtration.
显示更多 [+] 显示较少 [-]Statistical approach for determining the effects of microclimatic parameters on household spray products aerosol deposition
2015
Adeniran, Jamiu Adetayo | Sonibare, Jacob Ademola | Jimoda, Lukuman Adekilekun
The understanding of aerosol deposition in the indoor environment is relevant for assessing the exposure of occupants. This study investigates the effects of microclimatic parameters on the deposition rates of aerosols emanating from the use of household spray products in indoor environment. A three–factor factorial design was used to study the effects of interactions of air temperature, relative humidity and Air Exchange Rate (AER) on the deposition rate of particulate matter (PM). The highest deposition rate of 0.3μm particles (PM0.3) was 627.8h–1 when the relative humidity, temperature and AER were 40%, 40°C, and 12 h–1, respectively while the highest deposition rate of 5.0μm particles (PM5.0) was 709.20h–1 when the relative humidity, temperature and AER were 70%, 25 °C, and 12h–1, respectively. Regression analysis showed that air temperature and air exchange rate had significant effects on the deposition of PM0.3, while relative humidity and air exchange rate had significant effects on the deposition of PM5.0 at p<0.05. The experimental values were very close to the predicted values and were not statistically different at 95% confidence level.
显示更多 [+] 显示较少 [-]Equilibrium passive sampling as a tool to study polycyclic aromatic hydrocarbons in Baltic Sea sediment pore-water systems
2015
Lang, Susann-Cathrin | Hursthouse, Andrew | Mayer, Philipp | Kötke, Danjiela | Hand, Ines | Schulz-Bull, Detlef | Witt, Gesine
Solid Phase Microextraction (SPME) was applied to provide the first large scale dataset of freely dissolved concentrations for 9 polycyclic aromatic hydrocarbons (PAHs) in Baltic Sea sediment cores. Polydimethylsiloxane (PDMS) coated glass fibers were used for ex-situ equilibrium sampling followed by automated thermal desorption and GC–MS analysis. From the PAH concentrations in the fiber coating we examined (i) spatially resolved freely dissolved PAH concentrations (Cfree); (ii) baseline toxicity potential on the basis of chemical activities (a); (iii) site specific mixture compositions; (iv) diffusion gradients at the sediment water interface and within the sediment cores and (v) site specific distribution ratios. Contamination levels were low in the northern Baltic Sea, moderate to elevated in the Baltic Proper and highest in the Gulf of Finland. Chemical activities were well below levels expected to cause narcosis to benthos organisms. The SPME method is a very sensitive tool that opens new possibilities for studying the PAHs at trace levels in marine environments.
显示更多 [+] 显示较少 [-]The detrimental consequences for seagrass of ineffective marine park management related to boat anchoring
2015
La Manna, G. | Donno, Y. | Sarà, G. | Ceccherelli, G.
Posidonia oceanica (L.) Delile meadows are recognized as priority habitat for conservation by the EU Habitats Directive. The La Maddalena Archipelago National Park (Mediterranean Sea) P. oceanica meadow, the dominant coastal habitat of the area, is mostly threatened by boat anchoring. 12years after the establishment of mooring fields and anchoring restrictions, a study was conducted to measure their effectiveness on the conservation of seagrass and the mitigation of anchoring damage. We found that: (i) the condition of P. oceanica was disturbed, both in the mooring fields and in control locations; (ii) mooring fields and anchoring restrictions did not show to be an efficient system for the protection of seagrass, in fact anchor scars increased after the tourist season; (iii) the mooring systems had an impact on the surrounding area of the meadow, probably due to their misuse. On the basis of these results, management recommendations for marine parks are proposed.
显示更多 [+] 显示较少 [-]Porous membranes for ballast water treatment from microalgae-rich seawater
2015
Guilbaud, Julie | Massé, Anthony | Wolff, François-Charles | Jaouen, Pascal
The ballast waters from ships pose a major threat to oceans, notably because of the spread of microorganisms. The present study evaluates the techno-economic feasibility of implementing the membrane process to remove microalgae from seawater to be ballasted in a single step during planktonic bloom. The optimal conditions for the microfiltration of complex and reproducible synthetic seawater are a permeate flux and specific filtered volume of 100L.h−1.m−2 and 75L.m−2.cycle−1, respectively. Recovery of the membrane process represents about 76.6% and 62.7% of the annual cost for a cruise ship (5400 passengers) and liquefied natural gas (LNG) carrier (75,000m3 of liquid natural gas), followed by the membrane replacement cost (13.4% and 21.9%, respectively). The treatment costs are competitive with conventional treatments, even when the membrane process is more feasible for cruise ships due to its smaller capital cost and footprint.
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