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Analytical investigations on the lindane bioremediation capability of the demosponge Hymeniacidon perlevis
2015
Aresta, Antonella | Nonnis Marzano, Carlotta | Lopane, Chiara | Corriero, Giuseppe | Longo, Caterina | Zambonin, Carlo | Stabili, Loredana
Lindane is an organochlorine pesticide that has been widely used to treat agricultural pests. It is of particular concern because of its toxicity, persistence and tendency to bioaccumulate in terrestrial and aquatic ecosystems. In this context, we investigated the ability of the demosponge Hymeniacidon perlevis to bioremediate lindane polluted seawater during in vitro experimentation. Lindane was extracted by solid-phase micro-extraction (SPME) and determined by gas chromatography–mass spectrometry (GC–MS). Furthermore, we assessed the role exerted in lindane degradation by bacteria isolated from the sponge. Sponges showed low mortality in experimental conditions (lindane concentration 1μg/L) and were able to remove about 50% of the lindane content from seawater in 48h. Bacteria isolated from sponges showed a remarkable remediating capacity (up to 97% of lindane removed after 8-days). A lindane metabolite was identified, 1,3,4,5,6-pentachloro-cyclohexene. The results obtained are a prelude to the development of future strategies for the in situ bioremediation of this pollutant.
Show more [+] Less [-]Widespread contamination of coastal sediments in the Transmanche Channel with anti-androgenic compounds
2015
Alvarez-Muñoz, Diana | Indiveri, Paolo | Rostkowski, Pawel | Horwood, Julia | Greer, Emily | Minier, Christophe | Pope, Nick | Langston, William J. | Hill, Elizabeth M.
This study analysed the levels of androgen receptor antagonist activity in extracts of coastal sediments sampled from estuaries in southern UK and northern France. Anti-androgenic (AA) activity varied between <0.2 and 224.3±38.4μg flutamide equivalents/g dry weight of sediment and was significantly correlated with the total organic carbon and silt content of samples. AA activity was detected in tissues extracts of clams, Scrobicularia plana, sampled from a contaminated estuary, some of which was due to uptake of a series of 4 or 5 ring polycyclic aromatic hydrocarbons (PAHs). Initial studies also indicated that fractionated extracts of male, but not female, clams also contained androgen receptor agonist activity due to the presence of dihydrotestosterone in tissues. This study reveals widespread contamination of coastal sediments of the Transmanche region with anti-androgenic compounds and these contaminants should be investigated for their potential to disrupt sexual differentiation in aquatic organisms.
Show more [+] Less [-]Effect of orthophosphate and bioavailability of dissolved organic phosphorous compounds to typically harmful cyanobacterium Microcystis aeruginosa
2015
Li, Jihua | Wang, Zhongwei | Cao, Xin | Wang, Zhengfang | Zheng, Zheng
Results show that Microcystis aeruginosa can utilize both dissolved organic phosphorus (DOP) and orthophosphate (DIP) even under low phosphorus (P) conditions to sustain its growth. Total P concentrations decreased markedly in all three P source treatments. Alkaline phosphatase activity (APA) in the different P sources tested changed in response to the DOP and DIP. The APA of DOP groups remained low after decreasing significantly, but the APA in the DIP treatments remained high during the period of culture. Changes in APA at different PO43−–P concentrations in a culture medium revealed negative correlations between APA and DIP. However, a positive relationship was observed between APA and DOP under low P concentrations. These findings indicate that M. aeruginosa can regulate its physiological metabolism to acclimate to low ambient DIP environments.
Show more [+] Less [-]Polycyclic aromatic hydrocarbons in sediments at dredged material disposal sites around England: Concentrations in 2013 and time trend information at selected sites 2008–2013
2015
Rumney, Heather S. | Bolam, Stefan G. | Law, Robin J.
The maintenance of navigation channels to ports and the development of their facilities present a need to conduct dredging operations, and the subsequent disposal of dredged material at sea. Contaminant concentrations in candidate dredged material are determined and their possible impacts considered during the licensing process, which can result in the exclusion of some material from sea disposal. Monitoring of disposal sites is conducted in order to ensure that no undesirable impacts are occurring. In this study we consider the levels of polycyclic aromatic hydrocarbons (PAHs) in sediments at a number of disposal sites monitored in 2013 and variations in concentrations over time at three sites during the period 2008–2013. These were assessed using established sediment quality guidelines. Elevated PAH concentrations were generally observed only within the boundaries of the disposal sites studied.
Show more [+] Less [-]Analysis of optical and physical properties of aerosols during crop residue burning event of October 2010 over Lahore, Pakistan
2015
Tariq, Salman | ul-Haq, Zia | ʻAlī, Muḥammad
Aerosols released from biomass burning affect the tropospheric chemistry, radiation budget and cloud processes and hence can cause significant climate modifications. Due to certain economical reasons, the open burning of crop residue has become popular in Pakistan. In the present work we have analyzed the optical and physical properties of aerosols during crop residue burning over Lahore, a central location of Pakistan. The data from ground based Aerosol Robotic Network (AERONET), satellite based MODIS and CALIPSO remote sensing instruments have been used for the characterization of aerosols during crop residue burning event of October 2010. The maximum value (2.75) of daily mean AOD was observed on 20 October 2010 and the next highest value of 2.64 was observed on 19 October 2010, indicating heavy aerosol loading over Lahore on both days due to intense crop residue burning. The fine mode AOD values ranged from 0.14 to 2.68 (on 20 October 2010) with average value of 0.87 during October 2010 over Lahore. It was found that fine mode aerosols have greater contribution than coarse mode aerosols towards total aerosol burden indicating the presence of fine mode (crop residue burning) aerosols over Lahore. Cluster analysis showed that the mixed aerosols (biomass burning and urban-industrial) were present during the heavy aerosol loading period over Lahore. The highest volume concentration of fine mode occurred on 19 and 20 October 2010 representing the dominance of fine mode aerosols. Due to scattering of incoming solar radiation by intense smoke observed on 19 and 20 October 2010 high values of SSA (∼0.95) were found. HYSPLIT model backward trajectories showed that the winds transported aerosols from southeast and northwest directions.
Show more [+] Less [-]Indoor air quality assessment in painting and printmaking department of a fine arts faculty building
2015
Can, Emre | Özden Üzmez, Özlem | Döğeroğlu, Tuncay | Gaga, Eftade O.
Measurements for indoor air quality assessment were carried out in Painting and Printmaking Department of Anadolu University Faculty of Fine Arts in Turkey. Concentrations of nitrogen dioxide (NO2), ozone (O3) and 29 Volatile Organic Compounds (VOCs) were measured simultaneously by using diffusive samplers. Simultaneous outdoor measurements were also performed at some sampling points. Analyses of NO2 and ozone samples were performed by using ion chromatography and VOCs were analyzed by using gas chromatography-mass spectrometry. Indoor NO2 and ozone concentrations varied between 13.47–89.77 μg m−3 and 3.89–51.82 μg m−3, respectively. Average indoor NO2 concentration was obtained as 35.37 ± 10.9 μg m−3. Indoor/outdoor NO2 ratio (I/O) was found as 1.44 ± 0.4 which indicated the presence of some indoor sources. Average indoor ozone concentration was 9.97 ± 4.4 μg m−3 and I/O ratio was obtained lower than 1 (0.46 ± 0.4). The highest VOC concentrations were observed at workshops where oil painting and stained glass studies were performed. Especially, the concentrations obtained from the stained glass workshop (benzene: 3.98 ± 1.3 μg m−3, toluene: 999.33 ± 104.2 μg m−3, ethly benzene: 66.06 ± 16.1 μg m−3, m,p xylene: 129.44 ± 33.1 μg m−3, o-xylene: 76.14 ± 23.1 μg m−3) were much higher than the other sampling points. Toluene concentrations exceeded the WHO (World Health Organization) limit value (260 μg m−3 weekly average) at 40% of the sampling points. Cancer risks were estimated by using the personal exposure concentrations. Lifetime cancer risks for the people working in the department such as faculty members and technicians were obtained higher than USEPA acceptable risk value (1 × 10−6) while the risks for the students were below this value.
Show more [+] Less [-]Hypoxia in a transient estuary caused by summer lake-water discharge from artificial dykes into Chunsu Bay, Korea
2015
Jung, Kwang Young | Ro, Young Jae | Choi, Yang Ho | Kim, Baek Jin
We investigated bottom-water hypoxia induced by freshwater discharge from two artificial dykes into Chunsu Bay (CSB), Korea, during the summer of 2010. Field observations and model results of the dynamic and water-quality parameters indicated that the triggering mechanism of the hypoxia was strong stratification formed by the freshwater discharge from both dykes, which limited the dissolved oxygen (DO) supply in bottom water. Beneath the pycnocline, DO was consumed by sediment oxygen demand (SOD) during the summer. To investigate these processes, model experiments were conducted using a simplified DO budget model coupled with a 3D hydrodynamic model. The DO concentration in the northern part of CSB reached hypoxic conditions very quickly after 3.4days of discharge and lasted 18days until normal conditions resumed. In sum, in the CSB, marked stratification and its maintenance played a critical role in hypoxia in bottom water.
Show more [+] Less [-]The use of diagnostic ratios, biomarkers and 3-way Kohonen neural networks to monitor the temporal evolution of oil spills
2015
Fernández-Varela, R. | Gómez-Carracedo, M.P. | Ballabio, D. | Andrade, J.M.
Oil spill identification relies usually on a wealth of chromatographic data which requires advanced data treatment (chemometrics). A simple approach based on Kohonen neural networks to handle three-dimensional arrays is presented. A suite of 28 diagnostic ratios was considered to monitor six oils along four months. It was found that some traditional diagnostic ratios were not stable enough. In particular, alkylated PAHs (e.g. 1-methyldibenzothiophene, 4-methylpyrene, 27bbSTER and the TA21 and TA26 triaromatic steroids) seemed less resistant to medium-weathering than biomarkers. One (or two) ratios were found to differentiate each product: 30O, 28ab (and 25nor30ab), C3-dbt/C3-phe, 27Ts, TA26 and 29Ts characterized Ashtart, Brent, Maya, Sahara, IFO and Prestige oils, respectively.
Show more [+] Less [-]Changes to the biomass and species composition of Ulva sp. on Porphyra aquaculture rafts, along the coastal radial sandbank of the Southern Yellow Sea
2015
Huo, Yuanzi | Han, Hongbin | Shi, Honghua | Wu, Hailong | Zhang, Jianheng | Yu, Kefeng | Xu, Ren | Liu, Caicai | Zhang, Zhenglong | Liu, Kefu | He, Peimin | Ding, Dewen
Compositions, changes and biomass of attached Ulva species on Porphyra rafts along the radial sandbank in the Yellow Sea were investigated, and potential contributions to green tides was analyzed. Ulva prolifera, Ulva flexuosa and Ulva linza were all appeared throughout the investigated period. U. prolifera and U. flexuosa dominated attached Ulva population on Porphyra rafts. Attached Ulva species biomass showed obviously spatial and temporal variations. Temperature, Ulva microscopic propagules and human activities were main factors to influence attached Ulva species biomass. The total attached Ulva species biomass was more than 20,000 fresh weight tons in April, and the green tide causative species U. prolifera accounted 51.03% in April 2013 before green tides occurred. The high biomass of attached Ulva species would contribute most to green tides in the Yellow Sea. But how attached Ulva species on Porphyra rafts contributing to green tides in the Yellow Sea should be further studied.
Show more [+] Less [-]The seagrass Posidonia oceanica: Ecosystem services identification and economic evaluation of goods and benefits
2015
Campagne, Carole Sylvie | Salles, Jean-Michel | Boissery, Pierre | Deter, Julie
Posidonia oceanica is a marine angiosperm endemic from the Mediterranean. Despite their protection, its meadows are regressing. The economic valuation of ecosystem services (ES) assesses the contribution of ecosystems to human well-being and may provide local policy makers help in territorial development. To estimate the economic value of P. oceanica seagrass and the meadows that it forms to better account its presence in coastal development, identification and assessment of ES provided are first performed. Then goods and benefits (GB) and their economical values are estimated. In total, 25ES are identified and 7GB are economically evaluated. The economic value of GB provided by P. oceanica ranges between 25.3 million and 45.9 million€/year which means 283–513€/ha/year. Because of the lack of existing available data, only 7GB linked to 11/25ES have been estimated. Despite this overall undervaluation, this study offers a value for coastal development policies to take into account.
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