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Plastic litter in sediments from a marine area likely to become protected (Aeolian Archipelago's islands, Tyrrhenian sea)
2016
Fastelli, Paolo | Blašković, Andrea | Bernardi, Giulia | Romeo, Teresa | Čižmek, Hrvoje | Andaloro, Franco | Russo, Giovanni F. | Guerranti, Cristiana | Renzi, Monia
This research aims to define for the first time levels and patterns of different litter groups (macro, meso and microplastics) in sediments from a marine area designed for the institution of a new marine protected area (Aeolian Archipelago, Italy). Microplastics resulted the principal group and found in all samples analyzed, with shape and colours variable between different sampling sites. MPs levels measured in this study are similar to values recorded in harbour sites and lower than reported in Adriatic Sea, while macroplastics levels are notably lower than in harbor sites. Sediment grain-size and island extent resulted not significant in determining levels and distribution of plastic debris among islands. In the future, following the establishment of the MPA in the study area, these basic data will be useful to check for potential protective effects on the levels and distribution of plastic debris.
Mostrar más [+] Menos [-]Impact of sea-land breezes on 210Pb in southern Iberian Peninsula – Feasibility study on using submicron-sized aerosol particles to analyze 210Pb hourly patterns
2016
Hernández-Ceballos, M.A. | Sorribas, M. | San Miguel, E.G. | Cinelli Calvoli, Giovanni | Adame, J.A. | Bolívar, J.P.
This work addresses the impact of mesoscale circulations on 210Pb concentrations in southwestern Iberian Peninsula by analysing the 210Pb database at El Arenosillo station during 2004–2011 (128 periods with a time scale of 48 h).The analysis of surface winds during each one of these periods has revealed the positive impact of the two sea-land breeze patterns (pure and non-pure), previously identified in this region, on 210Pb activity concentrations. An average value of 0.80 ± 0.09 mBq m−3 was obtained for the pure pattern (34 periods), 0.54 ± 0.09 mBq m−3 for the non-pure pattern (23 periods) and 0.46 ± 0.04 mBq m−3 for the rest (71 periods).The analysis of one representative period of each sea-land breeze patterns is also presented. To perform this analysis we have used: hourly surface wind observations, surface wind fields simulated by the WRF mesoscale model and the hourly database of sub-micron-particle size range in the accumulation mode (NACC). The use of this type of particles to investigate the hourly temporal variability of 210Pb is based on the high correlation, obtained in the present work, between 210Pb activity and particles in the accumulation mode (R = 0.90).The analysis reveals that the highest concentrations of NACC, and hence, 210Pb, are obtained when the sampling area is under the influence of the pure breeze, due to it favours the accumulation of particles previously transported by Mediterranean flows along the Guadalquivir valley. In the case of the non-pure pattern, the increase in the concentration of particles is related to the arrival of background synoptic winds from the continental areas of western Iberian Peninsula. In the latest, the increment of NACC is faster and around 400 particles cm−3, while in the case of the pure pattern, it is progressive up to 1400 particles cm−3.
Mostrar más [+] Menos [-]Spatial variation of near-surface CO2 concentration during spring in Shanghai
2016
Liu, Min | Zhu, Xiyang | Pan, Chen | Ma, Yukun | Zhang, Hao | Jia, Wenxiao | Xiang, Weining
Urban area plays an important role in global carbon cycle, yet few efforts have been made to investigate CO2 concentration and its spatial heterogeneity in cities. Using Shanghai, the commercial and financial center of mainland China, as a case study, this paper explored the spatial pattern and determinants of near-surface urban CO2 concentration during spring. A total number of 173 sample points were collected covering the whole urban area, to examine the atmospheric CO2 concentration across various land use types (transportation, commercial, agricultural, recreational, institutional, residential and industrial land use) and urbanization gradients (heavy, moderately heavy, medium, moderately low, and low urbanization). CO2 concentrations were measured at a height of 2 m above the ground during 9:00–11:00 am in April and May 2014. The results indicated that CO2 concentration for the region was 409.4 ± 20.8 parts per million (ppm), showing significant spatial heterogeneity. The daytime ambient CO2 concentration varied across land use types (p < 0.05), with the highest and lowest value appeared in transportation area (420.5 ± 33.3 ppm) and agricultural land (398.9 ± 16.2 ppm). Across the urban gradients of Shanghai, a significant decrease of CO2 concentration was observed as the distance from urban core increased. With the influence of both high residential density and activities in production, the highest CO2 concentration occurred in moderate urbanization area (423.9 ± 29.3 ppm), rather than the high urbanization area (417.2 ± 17.5 ppm). Further analysis indicated that the percent of impervious surface cover (ISA) was an important indicator to describe near surface CO2 concentration with a positive correlation, and the percent of vegetation coverage (Veg) had lower explanatory power with a negative correlation. When buffer distance of spatial scale was 2000 m, atmospheric CO2 concentration showed the highest correlation with impervious surface and vegetation coverage.
Mostrar más [+] Menos [-]PCDD/Fs in soil and air and their possible sources in the vicinity of municipal solid waste incinerators in northeastern China
2016
Meng, Bo | Ma, Wanli | Liu, Li-Yan | Zhu, Ning-Zheng | Song, Wei-Wei | Lo, Ching Yee | Li, James | Kannan, Kurunthachalam | Li, Yi-Fan
Fly ash, flue gas, ambient air, and soil samples were collected to investigate concentrations, profiles, gas–particle partitioning, and air–soil exchange of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) in the vicinity of two municipal solid waste incinerators (MSWIs) in Harbin in northeastern China. The PCDD/F concentrations were 11 600–12 300 pg g−1 (597–615 pg WHO-TEQ g−1) in fly ash and 873–1120 fg m−3 (51.2–61.9 fg WHO-TEQ m−3) in air. The results of gas–particle partitioning possibly indicated the equilibrium state of PCDD/F during sampling period. For soil samples, both Enzyme-linked immuno-sorbent assay (ELISA) and high-resolution gas chromatography/high resolution mass spectrometry (HRGC/HRMS) were used. Significant correlations between the results from these two methods indicated that both methods are useful for PCDD/Fs analysis in soil. PCDD/Fs concentrations in soil samples ranged from 17.2 to 157 pg g−1 (0.59–8.81 pg WHO-TEQ g−1). Both Principal Component Analysis (PCA) and Hierarchical Cluster Analysis (HCA) suggested the sources of the emission from MSWIs and the historical emission from a petroleum refinery to PCDD/Fs in adjacent soils. The air–soil exchange analysis showed a net flux of PCDD/F from air to soil at all soil-sampling sites.
Mostrar más [+] Menos [-]Parasite fauna of Epinephelus coioides (Hamilton, 1822) (Epinephelidae) as environmental indicator under heavily polluted conditions in Jakarta Bay, Indonesia
2016
Neubert, Kilian | Yulianto, Irfan | Theisen, Stefan | Kleinertz, Sonja | Palm, Harry W.
The objective of this study was to assess the environmental conditions of a heavily polluted marine habitat using descriptors of fish parasites. Epinephelus coioides from Jakarta Bay as well as off Jakarta Bay was studied for metazoan parasites. Based on 70 fish and considering previous studies (230 fish), an environmental indicator system was designed. Including the recent study, a total of 51 parasite species have been recorded for E. coioides in Indonesian waters. Seven of them combined with five parasitological indices are useful descriptors for the environmental status of marine ecosystems. The results are visualized in a star graph. A significant different parasite infection between nine analyzed localities demonstrates the negative influence of the megacity Jakarta onto the coastal environment. We herewith complete a parasite based indicator system for Indonesian coastal waters, and suggest that it can be used in other marine habitats as well as for further epinephelids.
Mostrar más [+] Menos [-]Persistent organic pollutants and polycyclic aromatic hydrocarbons in penguins of the genus Pygoscelis in Admiralty Bay — An Antarctic specially managed area
2016
Montone, Rosalinda C. | Taniguchi, Satie | Colabuono, Fernanda I. | Martins, César C. | Cipro, Caio Vinícius Z. | Barroso, Hileia S. | da Silva, Josilene | Bícego, Márcia C. | Weber, Rolf R.
Persistent organic pollutants were assessed in fat samples of the Gentoo (Pygoscelis papua), Chinstrap (Pygoscelis antarcticus) and Adélie (Pygoscelis adeliae) penguins collected during the austral summers of 2005/06 and 2006/07 in Admiralty Bay, King George Island, Antarctica. The predominant organic pollutants were PCB (114 to 1115), polycyclic aromatic hydrocarbons (PAHs) (60.1 to 238.7), HCB (<0.3 to 132.2) and BDE-47 (<1.0 to 10.7) in ng g−1 wet weight. The mean concentrations of the majority of organic pollutants were similar among the three species of penguins. Chicks of all three species showed similar profiles of PCB congeners, with predominance of lower chlorinated compounds. The distribution of PAHs was similar in all birds, with a predominance of naphthalene and alkyl-naphthalene, which are the main constituents of arctic diesel fuel. These data contribute to the monitoring of the continued exposure to organic pollutants in the Antarctic biota.
Mostrar más [+] Menos [-]Beach debris on Aruba, Southern Caribbean: Attribution to local land-based and distal marine-based sources
2016
de Scisciolo, Tobia | Mijts, Eric N. | Becker, Tatiana | Eppinga, Maarten B.
Accumulation of marine (plastic) debris from local land-based and distal marine-based sources along coastlines is a pressing modern issue. Hitherto, assessing the relative contribution of pollution sources through beach surveys is methodologically challenging. We surveyed ten beaches along the leeward and windward coastlines of Aruba (southern Caribbean) to determine differences in macro- and meso-debris densities. Differences were quantified using three metrics: 1) the gradient in macro-debris density away from the waterfront; 2) the proportion of plastic within macro-debris; 3) the meso-:macro-debris ratio. Overall 42,585 macro-debris items and 884 meso-debris items were collected. The density of near-shore macro-debris, proportion of plastic debris herein, and meso-:macro-debris ratio were highest on the windward coastline. These results suggest that southern Caribbean windward coastlines are mainly exposed to debris originating from distal marine-based sources, and leeward coastlines to local land-based sources. Our metrics clearly reflect these differences, providing novel means to survey debris source origin.
Mostrar más [+] Menos [-]Comparison of wastewater-associated contaminants in the bed sediment of Hempstead Bay, New York, before and after Hurricane Sandy
2016
Fisher, Shawn C. | Phillips, Patrick J. | Brownawell, Bruce J. | Browne, James P.
Changes in bed sediment chemistry of Hempstead Bay (HB) have been evaluated in the wake of Hurricane Sandy, which resulted in the release of billions of liters of poorly-treated sewage into tributaries and channels throughout the bay. Surficial grab samples (top 5cm) collected before and (or) after Hurricane Sandy from sixteen sites in HB were analyzed for 74 wastewater tracers and steroid hormones, and total organic carbon. Data from pre- and post-storm comparisons of the most frequently detected wastewater tracers and ratios of steroid hormone and of polycyclic aromatic hydrocarbon concentrations indicate an increased sewage signal near outfalls and downstream of where raw sewage was discharged. Median concentration of wastewater tracers decreased after the storm at sites further from outfalls. Overall, changes in sediment quality probably resulted from a combination of additional sewage inputs, sediment redistribution, and stormwater runoff in the days to weeks following Hurricane Sandy.
Mostrar más [+] Menos [-]Assessing fuel spill risks in polar waters: Temporal dynamics and behaviour of hydrocarbons from Antarctic diesel, marine gas oil and residual fuel oil
2016
Brown, Kathryn E. | King, Catherine K. | Kotzakoulakis, Konstantinos | George, Simon C. | Harrison, Peter L.
As part of risk assessment of fuel oil spills in Antarctic and subantarctic waters, this study describes partitioning of hydrocarbons from three fuels (Special Antarctic Blend diesel, SAB; marine gas oil, MGO; and intermediate grade fuel oil, IFO 180) into seawater at 0 and 5°C and subsequent depletion over 7days. Initial total hydrocarbon content (THC) of water accommodated fraction (WAF) in seawater was highest for SAB. Rates of THC loss and proportions in equivalent carbon number fractions differed between fuels and over time. THC was most persistent in IFO 180 WAFs and most rapidly depleted in MGO WAF, with depletion for SAB WAF strongly affected by temperature. Concentration and composition remained proportionate in dilution series over time. This study significantly enhances our understanding of fuel behaviour in Antarctic and subantarctic waters, enabling improved predictions for estimates of sensitivities of marine organisms to toxic contaminants from fuels in the region.
Mostrar más [+] Menos [-]The assessment of airborne bacterial and fungal contamination emitted by a municipal landfill site in Northern Poland
2016
Breza-Boruta, B.
Airborne bacteria and fungi are important biological components of bioaerosol and play an important role in the conservation environmental. A microbiological study on bioaerosoles was carried out at the Municipal Waste Utilization Plant in Northern Poland and at points located beyond the facility at the distance of 150, 450, 1000 and 1250 m. The highest emission of bioaerosol occurred in the area of the waste landfill site and during compost pile turning. The total number of mesophilic bacteria, filamentous fungi and actinomycetes reached the values up to 104 CFU/m3. Strong air contamination with mannitol-positive and mannitol-negative staphylococci occurred remarkably more frequently in the area of the test facility than in the points beyond it. The number of indicator bacteria of Pseudomonas fluorescens was quite changeable and did not depend on a distance from pollutant emission source. The number of Escherichia coli rods remained at the low level of about 102 CFU/m3, and they were only isolated sporadically in the points beyond the landfill. The highest percentage of bacterial aerosol comprised Gram-positive cocci, and then Gram-positive bacilli. Mycological analyses confirmed the presence in the studied air of fungi with potentially allergic and mycotoxinogenic properties, such as: Aspergillus fumigatus, A. niger, A. terreus, Cladosporium herbarum and the genus Fusarium. The concentration level of microbial bioaerosol several times exceeded the threshold values recommended by the Polish Standards. The factors influenced the concentration of microorganisms in the tested air included the distance of the active landfill, weather conditions and the season.
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