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Assessing PAHs pollution in Qingdao coastal area (China) by the combination of chemical and biochemical responses in scallops, Chlamys farreri 全文
2014
Jin, Qian | Pan, Luqing | Liu, Dong | Hu, Fengxiao | Xiu, Meng
The PAHs concentrations in seawater and tissues from the scallop Chlamys farreri were detected in three sites in Qingdao, China in 2011. The PAHs concentrations in seawater ranged from 25.32ng/L to 314.62ng/L. There were significant differences (p<0.05) between the residual levels among scallop tissues. The highest concentrations of PAHs in seawater and tissues were found in S2. The ethoxyresorufin-O-deethylase (EROD) activity of the digestive gland and the malondialdehyde (MDA) contents of the digestive gland and gill were sensitive to PAHs (p<0.05). This study integrated the PAHs concentrations in seawater, residual levels, the variation of biochemical response and the correlation coefficient analysis, and concluded that Qingdao is a medium PAH-contaminated area on a global scale. The highest PAHs were accumulated in the digestive gland followed by the gill, soft tissue and adductor muscle. The EROD activity of the digestive gland and the MDA contents of the digestive gland and gill could be applied to assess the PAHs pollution status in Qingdao, China.
显示更多 [+] 显示较少 [-]Functional and molecular characterization of a lipopeptide surfactant from the marine sponge-associated eubacteria Bacillus licheniformis NIOT-AMKV06 of Andaman and Nicobar Islands, India 全文
2014
Lawrance, Anburajan | Balakrishnan, Meena | Joseph, Toms Cheriath | Palaiya Sukumaran, Dheenan | Nambali Valsalan, Vinithkumar | Gopal, Dharani | Ramalingam, Kirubagaran
The production of a lipopeptide surfactant from the sponge-associated eubacteria Bacillus licheniformis NIOT-AMKV06 from the Andaman and Nicobar Islands was investigated. The highest production was attained with glucose and yeast extracts as the carbon and nitrogen sources (1.789mgmL−1), respectively. The surfactant was highly stable over a pH range of 5.0–10 and a temperature range of 20–70°C with high NaCl concentrations. Excellent emulsification activity was exhibited by the purified surfactant with crude oil, kerosene, and diesel. A two-fold increase in surfactant production (3.0mgmL−1) was observed using the newly formulated medium in this study. The surfactant biosynthesis gene cluster (sfp, sfpO, and srfA) from B. licheniformis NIOT-AMKV06 was heterologously expressed in Escherichia coli, and the production was increased three-fold (11.78gL−1) over the original strain. The results confirm the potential of the surfactant for use in bioremediation of hydrocarbons in a marine environment and for enhanced oil recovery. To our knowledge, this is the first report on the ability of a hydrocarbon to degrade B. licheniformis from marine sponges for the biosynthesis of a potent lipopeptide surfactant possessing characteristics of maximum stability, outstanding surfactant activity, and exceptional emulsifying capability.
显示更多 [+] 显示较少 [-]Research on the fundamental principles of China’s marine invasive species prevention legislation 全文
2014
Bai, Jiayu
China’s coastal area is severely damaged by marine invasive species. Traditional tort theory resolves issues relevant to property damage or personal injuries, through which plaintiffs cannot cope with the ecological damage caused by marine invasive species. Several defects exist within the current legal regimes, such as imperfect management systems, insufficient unified technical standards, and unsound legal responsibility systems. It is necessary to pass legislation to prevent the ecological damage caused by marine invasive species. This investigation probes the fundamental principles needed for the administration and legislation of an improved legal framework to combat the problem of invasive species within China’s coastal waters.
显示更多 [+] 显示较少 [-]Ozone distributions and urban air quality during summer in Agra – a world heritage site 全文
2014
Saini, Renuka | Singh, Pradyumn | Awasthi, Brij B. | Kumar, Krishan | Taneja, Ajay
Unplanned urban and industrial growth and rise in population are the main factors that had led to air pollution problems. Surface ozone causes human health problems and environmental degradation and acts as a greenhouse gas. Surface ozone is the most significant key substance of photochemical smog. Dependence of air pollutants on meteorology is described with the objective of understanding the prevailing processes pollutants phase interaction. Rigorous measurements of gaseous materials (surface O3, NO2, CO, and SO2) and particulate matter (PM2.5) were carried out regularly during the summer season of 2012 at kerbsite of Agra to assess the characteristics of air pollutants. The air mass trajectories have been calculated using the HYSPLIT 4 and FLEXTRA model. The maximum hourly levels of these pollutants exceeded 116.5 ppb for O3, 96.2 ppb for NO2, 16 ppb for SO2, 4.60ppm for CO and 188µg/m3 for PM2.5. There is obvious diurnal variation in the concentration of surface ozone which clearly follows the diurnal variation of atmospheric temperature. The joint application of principal component analysis and clustering techniques to data collected has led to the recognition of inherent relationships between variables that have been associated with governing processes related to surface O3 formation. The effect of wind on pollutants appears to be noteworthy. We also found that, the maximum average concentrations of SO2 and O3 occurred at humidity ≤30% pinpointing for strong vertical mixing. For CO, NO2 and PM2.5 the maximum average concentrations occurred at humidity below 40%.
显示更多 [+] 显示较少 [-]National inventory of mercury release into different phase media estimated by UNEP Toolkit in South Korea 全文
2014
Pudasainee, Deepak | Seo, Yong-Chil | Kim, David Junghoon | Hong, Ji-Hyung | Park, Jung-Min
This paper summarizes the national inventory of mercury release into all media (air, water, land, impurity in products, general wastes and sector specific disposal) from South Korea, using UNEP mercury Toolkit. Total mercury input and release, distribution into different media, major contributors by source categories are discussed. The total quantified mercury release into different phase media was 284.0 t/y and 281.3 t/y in Level 1 and 2 estimation, respectively. Mercury release from primary metal production, waste incineration, extraction and use of fuels/energy sources were dominant. The replacement of output distribution factors in the Toolkit by real data from mass balance study in the anthropogenic sources resulted decrease in the share of mercury emission into air from 20.6% to 9.6%. Comparison of mercury releases into the atmosphere estimated by the Toolkit Level 2 with real distribution factors data and our earlier estimation with measurements in the selected industries showed only a little discrepancy, with reasonable variation. These differences are due to the use of efficient process technology and air pollution control devices. Since most mercury is released in waste and byproducts, recovery and safe storage issues are to be emphasized in the future studies.
显示更多 [+] 显示较少 [-]Marine phytoplankton motility sensor integrated into a microfluidic chip for high-throughput pollutant toxicity assessment 全文
2014
Zheng, Guo-xia | Li, Ya-jie | Qi, Lin-lin | Liu, Xian-ming | Wang, Hu | Yu, Shu-ping | Wang, Yun-hua
A microfluidic chip was designed to assess the toxicity of pollutants in a high-throughput way by using marine phytoplankton motility as a sensor signal. In this chip, multiple gradient generators (CGGs) with diffusible chambers enable large scale of dose-response bioassays to be performed in a simple way. Two mobile marine phytoplankton cells were confined on-chip and stimulated by 8 concentrations (generated by CGG) of Hg, Pb, Cu and phenol singly, as well as Cu and phenol jointly. CASA system was used to characterize motility by motile percentage (%MOT), curvilinear velocity (VCL), average path velocity (VAP) and straight line velocity (VSL). In all cases, dose-dependent inhibitions of motility were observed. In the present system, only 2h was needed to predict EC50. Thus, the developed microfluidic chip device was proved to be useful as a rapid/simple and high-throughput test method in marine pollution toxicity assessment.
显示更多 [+] 显示较少 [-]Respiration, growth and grazing rates of three ciliate species in hypoxic conditions 全文
2014
Rocke, Emma | Liu, Hongbin
Marine hypoxic episodes are affecting both marine and freshwater bodies all over the world. Yet, limited data exists with regard to the effects of decreasing oxygen on protist metabolism. Three ciliate species were therefore isolated from Hong Kong coastal waters. Controlled hypoxic conditions were simulated in the lab environment, during which time growth, respiration and grazing rates were measured. Euplotes sp. and a Oxytrichidae-like ciliate showed decreased growth and respiration below 2.5mgO2L−1, however Uronema marinum kept steady growth and respiration until below 1.5mgO2L−1. Euplotes sp. and the Oxytrichidae-like ciliate had the highest ingestion rate, which dropped significantly below 3.0mgO2L−1. U.marinum grazing rates were affected at and below 1.5mg O2L−1, correlating with their drop in growth and respiration at this lower concentration. This study illustrates the slowing metabolism of key grazing protists, as well as species-specific tolerance in response to hypoxia.
显示更多 [+] 显示较少 [-]Underwater noise pollution in a coastal tropical environment 全文
2014
Bittencourt, L. | Carvalho, R.R. | Lailson-Brito, J. | Azevedo, A.F.
Underwater noise pollution has become a major concern in marine habitats. Guanabara Bay, southeastern Brazil, is an impacted area of economic importance with constant vessel traffic. One hundred acoustic recording sessions took place over ten locations. Sound sources operating within 1km radius of each location were quantified during recordings. The highest mean sound pressure level near the surface was 111.56±9.0dB re 1μPa at the frequency band of 187Hz. Above 15kHz, the highest mean sound pressure level was 76.21±8.3dB re 1μPa at the frequency 15.89kHz. Noise levels correlated with number of operating vessels and vessel traffic composition influenced noise profiles. Shipping locations had the highest noise levels, while small vessels locations had the lowest noise levels. Guanabara Bay showed noise pollution similar to that of other impacted coastal regions, which is related to shipping and vessel traffic.
显示更多 [+] 显示较少 [-]Disturbance of recruitment success of mantis shrimp in Tokyo Bay associated with effects of hypoxia on the early life history 全文
2014
Kodama, Keita | Tajima, Yoshihiro | Shimizu, Takamichi | Ohata, Satoshi | Shiraishi, Hiroaki | Horiguchi, Toshihiro
We investigated effects of severe hypoxia (dissolved oxygen <1mll−1) on recruitment of mantis shrimp Oratosquilla oratoria in Tokyo Bay. Ten-year field surveys were conducted to examine quantitative relationships in annual mean densities of larvae and juveniles, and spatial distribution of juveniles and severe hypoxia. There was no significant correlation between annual mean densities of larvae and juveniles, suggesting that mortality during larval or juvenile stages varies among years, which might have regulated abundance of young-of-the-year juveniles. Juvenile density was low in the severely hypoxic area, implying that hypoxia could affect survivals and spatial distribution of juveniles. Meanwhile, there are yearly fluctuations in juvenile density in normoxic areas of both northern and southern part of the bay. This evidence suggests that abundance of post-settled juveniles might have been determined by not only effects of hypoxia, but also other factors influencing mortality during the early life stages.
显示更多 [+] 显示较少 [-]Photochemical transformation of 2,2′,4,4′-tetrabromodiphenyl ether (BDE-47) in surface coastal waters: Effects of chloride and ferric ions 全文
2014
Zhao, Qian | Zhao, Huimin | Quan, Xie | Chen, Shuo | Zhang, Yaobin
The effects of several aquatic environmental factors on the photochemical transformation of 2,2′,4,4′-tetrabromodiphenyl ether (BDE-47) have been investigated. Ferric ion (Fe(III)) has been found to promote the phototransformation of BDE-47, and this process is further enhanced with the added chloride ion (Cl−), while it is suppressed with increasing pH. Electron spin resonance results show that the formation of hydroxyl radical, and the added Cl− could influence the generation of hydroxyl radical in Fe(III) solution. Hence, Cl− enhances the phototransformation of BDE-47 most probably because of the reaction with Fe(III) species under irradiation, yielding hydroxyl and chloride radicals. These radicals can not only decompose PBDEs, but also lead to their photodebromination and photochlorination. These results indicate that the aquatic environmental factors and Cl− in particular played an important role in the photochemical transformation process of PBDEs, providing insight into the likely fate of PBDEs in the marine environment.
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