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Percentage of microbeads in pelagic microplastics within Japanese coastal waters Full text
2016
Isobe, Atsuhiko
To compare the quantity of microbeads with the quantity of pelagic microplastics potentially degraded in the marine environment, samples were collected in coastal waters of Japan using neuston nets. Pelagic spherical microbeads were collected in the size range below 0.8mm at 9 of the 26 stations surveyed. The number of pelagic microbeads smaller than 0.8mm accounted for 9.7% of all microplastics collected at these 9 stations. This relatively large percentage results from a decrease in the abundance of microplastics smaller than 0.8mm in the upper ocean, as well as the regular loading of new microbeads from land areas, in this size range. In general, microbeads in personal care and cosmetic products are not always spherical, but rather are often a variety of irregular shapes. It is thus likely that this percentage is a conservative estimate, because of the irregular shapes of the remaining pelagic microbeads.
Show more [+] Less [-]Heavy metal accumulation in tissues of two sea cucumbers, Holothuria leucospilota and Holothuria scabra in the northern part of Qeshm Island, Persian Gulf Full text
2016
Mohammadizadeh, Maria | Bastami, Kazem Darvish | Ehsanpour, Maryam | Afkhami, Majid | Mohammadizadeh, Flora | Esmaeilzadeh, Marjan
The concentrations of some heavy metals (Cd, Cu, Zn andPb) were investigated in the sediments and the two species of sea cucumber (Holothuria leucospilota and Holothuria scabra) from northern part of Qeshm Island, Persian Gulf. The levels of Cu, Zn and Pb in sediment varied significantly among sampling sites (p<0.05). The highest levels of Zn and Pb in H. leucospilota were recorded in body wall whereas the highest contents of Zn and Pb in H. scabra were measured in respiratory tree organ, respectively. Cu and Cd were the most abundant elements in gonads of H. leucospilota while highest levels of Cd and Cu in H. scabra were measured in the gonad and derm, respectively. Cu and Zn concentrations were below permissible limits for human consumption while Cd and Pb were above permissible limits for human consumption.
Show more [+] Less [-]A novel biomarker for marine environmental pollution of HSP90 from Mytilus coruscus Full text
2016
Liu, Huihui | Wu, Jiong | Xu, Mengshan | He, Jianyu
Heat shock protein 90 (HSP90) is a conserved molecular chaperone contributing to cell cycle control, organism development and the proper regulation of cytosolic proteins. The full-length HSP90 cDNA of Mytilus coruscus (McHSP90, KT946644) was 2420bp, including an ORF of 2169bp encoding a polypeptide of 722 amino acids with predicted pI/MW 4.89/83.22kDa. BLASTp analysis and phylogenetic relationship strongly suggested McHSP90 was a member of HSP90 family, and it was highly conserved with other known HSP90, especially in the HSP90 family signatures, ATP/GTP-Binding sites and ‘EEVD’ motif. The mRNA of McHSP90 in haemolymph was upregulated in all treatments including Vibrio alginolyticus and Vibrio harveyi challenge, metals stresses (copper and cadmium) and 180 CST fuel exposure. All the results implied the expression of McHSP90 could be affected by Vibrio challenge and environmental stress, which might help us gain more insight into the molecular mechanism of HSP against adverse stresses in mollusca.
Show more [+] Less [-]The development of a preliminary rock reef fish multimetric index for assessing thermal and urban impacts in a tropical bay Full text
2016
Teixeira-Neves, Tatiana Pires | Neves, Leonardo Mitrano | Araújo, Francisco Gerson
We developed a multimetric index for assessing ecological conditions in rocky reefs areas to evaluate thermal and urban influences on fish community. Eight metrics were selected to assess thermal influence: (1) total number of species; (2) number of water column species; (3) number of transient species; (4) density of individuals with low resilience; (5) density of omnivores; (6) density of carnivores; (7) number of cryptic species; (8) density of herbivores. For urban influence, six metrics were selected: (1) total density; (2) ratio between the number of rare species and the total number of species; (3) density of individuals with heavy fishing pressure; (4) number of resident species; (5) number of cryptic species; (6) density of herbivores. This preliminary index succeed in discriminating control/impacted sites and proved to be an important tool to assess impacts that alter fish community and have potential to be used in tropical rock reef coastal areas.
Show more [+] Less [-]Anthropogenic influences on aerosols at Ny-Ålesund in the summer Arctic Full text
2016
Zhan, Jianqiong | Li, Wei | Chen, Liqi | Lin, Qi | Gao, Yuan
The Arctic atmosphere has been disturbed by human activities. To improve the understanding of anthropogenic influences, major ionic species and carbonaceous components were measured at Ny-Ålesund in July 2012. The results suggested that Na+ and Cl− are the dominant water soluble inorganic species, accounting for 57 ± 17% of the mass of measured ionic species, and 61% of the variance in organic carbon can be explained by oceanic emissions. Aerosols in this area were found to be altered by secondary production involving oxides of sulfur, nitrogen and ammonia from anthropogenic activities, resulting in relative high concentrations of secondary inorganic aerosols (SIA) (such as non-sea salt (nss)-SO42−, NO3− and NH4+), with a mean concentration of 158 ng m−3. SIAs were featured by a mean [NH4+]/[nss-SO42−] ratio of 0.57 and a neutralization ratio (NR) of 0.074, indicating a deficit of NH4+. Thus, the production of particulate NH4 NO3 was strongly limited and SIAs were likely to remain in more acidic forms, NH4HSO4 or H2SO4 rather than as (NH4)2SO4. Chloride depletion of 11%–22% occurred in the samples with high concentrations of excess acidic species (defined as [nss-SO42− + NO3− − NH4+]) and high sea salts. The formation of SIAs and chloride depletion appeared to produce acidic aerosols with a mean pH of 4.51 and high free [H] concentrations of 3.06 ± 0.75 nmol m−3 in aerosols, accounting for 77% of the total [H] concentration. This implies that anthropogenic species could be engaged efficiently in modifying of the properties of aerosols at Ny-Ålesund.
Show more [+] Less [-]Collaboration between central and state government and environmental quality: Evidences from Indian cities Full text
2016
Sinha, Avik | Rastogi, Siddhartha K.
Within the context of coordination level between state and central government, we develop an econometric model to estimate the association between income and ambient air pollution, considering the societal preferences jointly influenced by the citizens and the government. We obtain empirical evidence supporting our hypothesis that state level coalition government can effectively improve quality of environment by means of reducing ambient air pollution level. This impact can be increased or decreased based on the societal preferences of the citizens, based on the area of inhabitance and irrespective of the choice of pollutants.
Show more [+] Less [-]Potential effects of sediment contaminants on diatom assemblages in coastal lagoons of New Jersey and New York States Full text
2016
Potapova, Marina | Desianti, Nina | Enache, Mihaela
Sediment samples from the coastal lagoons and estuaries of New York and New Jersey were used to investigate the influence of contaminants on diatom assemblages. Multivariate analyses demonstrated correspondence between composition of diatom assemblages and concentrations of several metals and total PAH. The effects of the individual contaminants were difficult to disentangle because of the considerable correlations between their concentrations. The most conspicuous trend was the increase in the relative abundance of small centric planktonic diatoms in response to contamination and the corresponding decrease in the benthic flora. The high relative abundance of planktonic species on contaminated sediments apparently resulted not so much from their tolerance to pollution, but from the paucity of benthic species. A comparison of the assemblages on the surface and at the depth of approximately 8–10cm revealed a statistically significant temporal change in community composition towards planktonic diatoms.
Show more [+] Less [-]Natural and man-made radionuclides in sediments of an inlet in Rio de Janeiro State, Brazil Full text
2016
Carvalho, Franciane Martins de | Lauria, Dejanira da Costa | Ribeiro, Fernando Carlos Araújo | Fonseca, Rafael Tonelli | Peres, Sueli da Silva | Martins, Nádia Soido Falcão
The distribution of natural radionuclides 226Ra, 228Ra, 40K and man-made radionuclides (54Mn, 60Co and 137 Cs) in the surface sediments of an inlet of Ribeira Bay were investigated. Sediment samples were collected and analyzed for radionuclides, organic matter, carbonate, sulfate, cationic exchange capacity and grain size composition. The natural radionuclide concentrations ranged from 4.4 to 45, from 10 to 93, from 66 to 1347Bq·kg−1 dry weight for 226Ra, 228Ra and 40K, respectively. Natural radionuclide concentrations tend to be higher in the silt fraction, which determines their pattern distributions. Only one sample presented measurable concentration for 137Cs, while 54Mn was detected in two samples and 60Co in four sediment samples. Man-made radionuclides present a maximum value of dose external four times lower than the normal background and the potential risk due to the presence of man-made radionuclides in sediments is lower than the risk provided by the natural radionuclides.
Show more [+] Less [-]Polycyclic aromatic hydrocarbons in PM2.5 and PM10 atmospheric particles in the Metropolitan Area of Costa Rica: Sources, temporal and spatial variations Full text
2016
Murillo, Jorge Herrera | Villalobos, Maria Chaves | Rojas Marín, José Félix | Guerrero, Víctor Hugo Beita | Solórzano Arias, David
Polycyclic aromatic hydrocarbons (PAHs) concentrations in PM10 and PM2.5 particles were measured at 14 monitoring sites (12 for PM10 and 2 for PM2.5), located in the Metropolitan Area of Costa Rica, from January to November 2013. High-volume air samplers with pretreated quartz filters were used to collect the particles. The analytical determination was carried out using high-performance liquid chromatography (HPLC). The most abundant PAHs were benzo[a]anthracene, indeno(1,2,3-cd)pyrene, dibenz[a,h]anthracene and acenaphthylene. Ratios obtained by correlating the concentration of some PAHs, both PM10 and PM2.5, suggest that gasoline and diesel vehicles are the main sources in the area being studied. This is consistent with the results obtained when applying the positive matrix factorization (PMF) analysis, since vehicles accounted for 62–74% of total emissions in the area; burning wood fuel was the second source of emissions, contributing between 7 and 15%; and road dust was third, with almost 8%.
Show more [+] Less [-]Health effects of air pollution: An empirical analysis for developing countries Full text
2016
Fotourehchi, Zahra
In this research, we examine the effects of PM10 and CO2 air pollutants on infant mortality and life expectancy at birth, in 60 developing countries during the period 1990–2010 by using unbalanced panel data and recursive simultaneous equations model. Our results show that the gains are obtained in the health status through the improvement in socio-economic conditions can be canceled by PM10 and CO2 air pollutants. Therefore, health policies which just focus on socio-economic aspects and ignore the adverse impacts of the air pollution may do little in efforts directed to improve the current health status of developing countries.
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