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Occurrence, distribution, and risk assessment of alkylphenols, bisphenol A, and tetrabromobisphenol A in surface water, suspended particulate matter, and sediment in Taihu Lake and its tributaries 全文
2016
Liu, Dan | Liu, Jining | Guo, Min | Xu, Huaizhou | Zhang, Shenghu | Shi, Lili | Yao, Cheng
The occurrence and distribution of nine selected compounds were investigated in surface water, suspended particulate matter (SPM), and sediment in Taihu Lake and its tributaries. With the exception of 4-Butylphenol, all compounds were detected in at least two phases, and nonylphenol (NP) and 4-tert-Octylphenol (4-OP) were the predominant alkylphenols (APs) in the lake. A significant correlation was observed between NP and 4-OP, indicating that they may share the same source. Moreover, surface water phase was the dominant sink of Bisphenol A (BPA) in the aquatic environment. The concentrations of BPA between the surface water and SPM phases were closely related to each other. In addition, Tetrabromobisphenol A (TBBPA) exhibited relatively higher concentrations and detection frequencies in the SPM. Risk assessment revealed greater risk associated with the surface water than the sediment, indicating that the discharge of industrial wastewater and domestic sewage poses a serious threat to aquatic ecosystems.
显示更多 [+] 显示较少 [-]Environmental dynamics of red Noctiluca scintillans bloom in tropical coastal waters 全文
2016
Baliarsingh, S.K. | Lotliker, Aneesh A. | Trainer, Vera L. | Wells, Mark L. | Parida, Chandanlal | Sahu, Biraja K. | Srichandan, Suchismita | Sahoo, Subhashree | Sahu, K.C. | Kumar, T Sinivasa
An intense bloom of red Noctiluca scintillans (NS) occurred off the Rushikulya estuarine region along the east coast of India, an important site for mass nesting events of the vulnerable Olive Ridley sea turtle. At its peak, densities of NS were 3.3×105 cells-l−1, with low relative abundance of other phytoplankton. The peak bloom coincided with high abundance of gelatinous planktivores which may have facilitated bloom development by their grazing on other zooplankton, particularly copepods. Ammonium concentrations increased by approximately 4-fold in the later stages of bloom, coincident with stable NS abundance and chlorophyll concentrations in the nano- and microplankton. This increase likely was attributable to release of intracellular ammonium accumulated through NS grazing. Dissolved oxygen concentrations decreased in sub-surface waters to near hypoxia. Micro-phytoplankton increasingly dominated chlorophyll-a biomass as the bloom declined, with diminishing picoplankton abundance likely the result of high predation by the ciliate Mesodinium rubrum. Together, these data illustrate factors that can disrupt ecosystem balance in this critically important Indian coastal region.
显示更多 [+] 显示较少 [-]Application of macrobenthic diversity to estimate ecological health of artificial oyster reef in Yangtze Estuary, China 全文
2016
In this study, several macrobenthic diversity investigations were performed in Yangtze Estuary Oyster Reef, the largest artificial oyster reef in China, from 2012 to 2014. The sampling sites of the south branch showed considerably higher diversity than those of the north branch. The richness measures exhibited a significant increasing trend from low- to high-salinity zone; however, the evenness measures were typically high in the middle-salinity zone. During the past decade, the results were combined with historical data to detect the changes in macrobenthos. The variation in substrate organisms and macrobenthic diversity followed a steady trend after a major fluctuation. Redundancy analysis indicated that the water salinity and substrate factors were the main indicators that influence macrobenthic distribution. All sampling sites in the south branch were protected by a nature reserve. However, the N2 and N6 sites in the north branch were subjected to severe and mild human interventions, respectively.
显示更多 [+] 显示较少 [-]Behavioral response of brown meagre (Sciaena umbra) to boat noise 全文
2016
La Manna, G. | Manghi, M. | Perretti, F. | Sarà, G.
Underwater man-made noise is recognized as a major global pollutant in the 21st Century, and its reduction has been included in national and international regulations. Despite the fact that many studies have pointed out the ecological impact of noise on marine organisms, few studies have investigated - in a field context - the behavioral response to boat noise in fish. In the present study we measure how Sciaena umbra reacts to boat noise. We found that boat noise: i) increased duration of flight reactions and number of individuals performing them, ii) increased the frequency of hiding behaviors, and iii) did not elicit a change in fish activity level and sound emission. Flights and hiding behavior, usually related to predation risk, were not uniform between individuals and showed a quick recovery after noise exposure. On the basis of these results, potential metabolic, physiological and behavioral consequences are discussed and management recommendations are proposed.
显示更多 [+] 显示较少 [-]Bayesian spatial modeling of cetacean sightings during a seismic acquisition survey 全文
2016
Vilela, Raul | Pena, Ursula | Esteban, Ruth | Koemans, Robin
A visual monitoring of marine mammals was carried out during a seismic acquisition survey performed in waters south of Portugal with the aim of assessing the likelihood of encountering Mysticeti species in this region as well as to determine the impact of the seismic activity upon encounter.Sightings and effort data were assembled with a range of environmental variables at different lags, and a Bayesian site-occupancy modeling approach was used to develop prediction maps and evaluate how species-specific habitat conditions evolved throughout the presence or not of seismic activity.No statistical evidence of a decrease in the sighting rates of Mysticeti by comparison to source activity was found. Indeed, it was found how Mysticeti distribution during the survey period was driven solely by environmental variables.Although further research is needed, possible explanations may include anthropogenic noise habituation and zone of seismic activity coincident with a naturally low density area.
显示更多 [+] 显示较少 [-]Percentage of microbeads in pelagic microplastics within Japanese coastal waters 全文
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.
显示更多 [+] 显示较少 [-]Heavy metal accumulation in tissues of two sea cucumbers, Holothuria leucospilota and Holothuria scabra in the northern part of Qeshm Island, Persian Gulf 全文
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.
显示更多 [+] 显示较少 [-]A novel biomarker for marine environmental pollution of HSP90 from Mytilus coruscus 全文
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.
显示更多 [+] 显示较少 [-]The development of a preliminary rock reef fish multimetric index for assessing thermal and urban impacts in a tropical bay 全文
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.
显示更多 [+] 显示较少 [-]Anthropogenic influences on aerosols at Ny-Ålesund in the summer Arctic 全文
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.
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