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Magnetic assessment and pollution status of beach sediments from Kerala coast (southwestern India) Full text
2017
Chaparro, Marcos A.E. | Suresh, G. | Chaparro, Mauro A.E. | Ramasamy, V. | Sundarrajan, M.
Natural and anthropogenic activities along the coastal region of densely populated Kerala may introduce hazardous components into the coastal environment. The present study aimed to investigate the sources and impacts of hazardous components in beach sediments by environmental magnetism methods as additional tools. Magnetic parameters (such as mass-specific magnetic susceptibility χ=−1.2–154.4×10−8m3kg−1) and ratios that describe the magnetic properties of minerals such as Fe-oxides, indicate variable concentration of mixtures of magnetite and hematite (magnetite/hematite). The direct significant relationships between the variables indicate that higher concentration magnetic parameters are associated with higher radionuclides and metal contents. Magnetic properties and multivariate statistical analyses evidence the presence of contrasting groups defined only using a reduced number of magnetic variables. One of these groups, the central area of the Kerala coastline, showed the highest magnetic concentrations of mixtures of magnetite/hematite and higher values (up to 6.7) of pollution load index because of extensive anthropogenic activities.
Show more [+] Less [-]Incidence of marine debris in seabirds feeding at different water depths Full text
2017
Tavares, D.C. | de Moura, J.F. | Merico, A. | Siciliano, S.
Marine debris such as plastic fragments and fishing gears are accumulating in the ocean at alarming rates. This study assesses the incidence of debris in the gastrointestinal tracts of seabirds feeding at different depths and found stranded along the Brazilian coast in the period 2010–2013. More than half (55%) of the species analysed, corresponding to 16% of the total number of individuals, presented plastic particles in their gastrointestinal tracts. The incidence of debris was higher in birds feeding predominantly at intermediate (3–6m) and deep (20–100m) waters than those feeding at surface (<2m). These results suggest that studying the presence of debris in organisms mainly feeding at the ocean surface provides a limited view about the risks that this form of pollution has on marine life and highlight the ubiquitous and three-dimensional distribution of plastic in the oceans.
Show more [+] Less [-]Determination of buildup and dilution of wastewater effluent in shellfish growing waters through a modified application of super-position Full text
2017
Goblick, Gregory N. | Ao, Yaping | Anbarchian, Julie M. | Calci, Kevin R.
Since 1925, dilution analysis has been used to minimize pathogenic impacts to bivalve molluscan shellfish growing areas from treated wastewater effluent in the National Shellfish Sanitation Program (NSSP). For over twenty five years, the U.S. Food and Drug Administration (FDA) has recommended a minimum of 1000:1 dilution of effluent within prohibited closure zones established around wastewater treatment plant (WWTP) discharges. During May 2010, using recent technologies, a hydrographic dye study was conducted in conjunction with a pathogen bioaccumulation study in shellfish adjacent to a WWTP discharge in Yarmouth, ME. For the first time an improved method of the super-position principle was used to determine the buildup of dye tagged sewage effluent and steady state dilution in tidal waters. Results of the improved method of dilution analysis illustrate an economical, reliable and more accurate and manageable approach for estimating the buildup and steady state pollutant conditions in coastal and estuarine waters.
Show more [+] Less [-]Chronology of anthropogenic impacts reconstructed from sediment records of trace metals and Pb isotopes in Todos os Santos Bay (NE Brazil) Full text
2017
Andrade, R.L.B. | Hatje, V. | Masqué, P. | Zurbrick, C.M. | Boyle, E.A. | Santos, W.P.C.
The evolution of the impacts of anthropogenic activities in Todos os Santos Bay was evaluated by profiles of trace metals and Pb isotopes determined in sediment cores. Fluxes of metals increased up to 12, 4 and 2 times for Cu, Pb, and Zn, respectively, compared to those recorded in the beginning of the 20th century. Stable Pb isotopes identified a decommissioned lead smelter and burning of fossil fuels as the main sources of Pb. Most metals showed minor to moderate enrichment factors (EF<4), but Cu and Pb were highly enriched (EF=28 and 6, respectively) at the Aratu harbor. Temporal changes in sediments were associated to different activities, namely Pb smelting, burning of fossil fuels, maritime traffic, petroleum related activities, inputs of domestic effluents, and changes in land uses. The effects of the implementation of environmental policies to improve the waters of the bay could not be identified in the evaluated cores.
Show more [+] Less [-]Effects of aerobic respiration and nitrification on dissolved inorganic nitrogen and carbon dioxide in human-perturbed eastern Jiaozhou Bay, China Full text
2017
Han, Ping | Li, Yunxiao | Yang, Xufeng | Xue, Liang | Zhang, Longjun
Aerobic respiration and nitrification are important processes for dissolved inorganic nitrogen (DIN) composition change and CO2 production in human-perturbed coastal waters. On-site incubations and field investigations were conducted in the eastern Jiaozhou Bay, a high-urbanization region, from May to August 2014. Results show that aerobic respiration rates reached 15.58μmolO2L−1d−1, and NH4+ and NO2− oxidation rates were 0.53 and 0.13μmolNL−1d−1, respectively, in the human-perturbed northeastern area. The intense aerobic respiration there contributed to high-concentration NH4+, and meanwhile caused a pH decrease of 0.042units and a pCO2 increase of 166μatm per day. Moreover, the linear relationship between excess CO2 and apparent oxygen utilization suggested that the excess CO2 in the entire eastern Jiaozhou Bay was mainly from the aerobic respiration. This study may help us better understand the role of aerobic respiration in DIN composition and CO2 sink/source pattern in coastal waters.
Show more [+] Less [-]New Particle Formation and Growth Mechanisms in Highly Polluted Environments Full text
2017
You, Huan | Ren, Lili | Kanawade, Vijay P.
New particle formation (NPF) has been expected to be less favored in the polluted atmosphere than in the clean atmosphere. However, highly polluted regions in developing countries like China and India are becoming hot spots of NPF. Understanding nucleation and growth mechanisms of aerosol particles in polluted environments have important implications in their global climate impact and health effect. This paper reviewed recent publications from atmospheric field and laboratory measurements under conditions relevant to the polluted atmosphere. NPF probability in polluted environments was discussed by exploring the uncertainties in coagulation sink and growth rate estimations. Future directions and challenges in understanding NPF in highly polluted environments are presented.
Show more [+] Less [-]The relation between columnar and surface aerosol optical properties in a background environment Full text
2017
Szczepanik, D. | Markowicz, K.M.
This work presents the results of observation and the numerical simulation relationship between columnar and surface aerosol optical properties. The presented data include sun photometer nephelometer, aethalometer, and ceilometer observation, as well as the Navy Aerosol Analysis and Prediction System (NAAPS) re-analysis obtained between 2013 and 2016. Measurements were made in Strzyzow station (south-eastern part of Poland), which belongs to the AERONET and Poland-AOD network. Observation and simulation data show that the correlation coefficient between aerosol optical depth and surface aerosol scattering coefficient depends on the averaging period. For the monthly mean both parameters are negatively correlated as a result of the seasonal variability of anthropogenic emission in Central Europe and long-range transport of natural aerosol, as well as the change of the meteorological conditions. Reduction of the averaging time leads to an increase in the correlation coefficient, which is almost zero for a 10-day period and 0.4 ± 0.05 when the six-hour data are selected. In addition, the correlation between columnar and surface aerosol optical properties shows significant variation with surface temperature gradient. During convective conditions the correlation coefficient between aerosol optical depth and aerosol scattering coefficient is as much as 0.89 ± 0.03 while during inversion it is approximately 0.48 ± 0.08.
Show more [+] Less [-]Microplastics as a vector for the transport of the bacterial fish pathogen species Aeromonas salmonicida Full text
2017
Viršek, Manca Kovač | Lovšin, Marija Nika | Koren, Špela | Kržan, Andrej | Peterlin, Monika
Microplastics is widespread in the marine environment where it can cause numerous negative effects. It can provide space for the growth of organisms and serves as a vector for the long distance transfer of marine microorganisms. In this study, we examined the sea surface concentrations of microplastics in the North Adriatic and characterized bacterial communities living on the microplastics. DNA from microplastics particles was isolated by three different methods, followed by PCR amplification of 16S rDNA, clone libraries preparation and phylogenetic analysis. 28 bacterial species were identified on the microplastics particles including Aeromonas spp. and hydrocarbon-degrading bacterial species. Based on the 16S rDNA sequences the pathogenic fish bacteria Aeromonas salmonicida was identified for the first time on microplastics. Because A. salmonicida is responsible for illnesses in fish, it is crucial to get answers if and how microplastics pollution is responsible for spreading of diseases.
Show more [+] Less [-]Fast assessment of bioaccessible metallic contamination in marine sediments Full text
2017
Terán-Baamonde, J. | Carlosena, A. | Soto-Ferreiro, R.M. | Andrade, J.M. | Prada, D.
A fast (16min) procedure to assess the bioaccessible metallic fraction of Cd, Cr, Cu, Ni, Pb and Zn simultaneously extracted (SEM) from marine sediments plus an indirect approach to determine acid volatile sulfides (AVS) are presented. For the extraction process magnetic agitation was compared with ultrasonic stirring (using a bath and a probe), and several stirring times were assayed. The proposed SEM procedure uses an ultrasonic probe and 1mL of HCl. It dramatically minimizes the turnaround time and the residues. AVS were evaluated as the difference between the amounts of sulphur in the solid residue after the extraction and total sulphur in the original sample. These procedures are fast, easy to implement and cost-effective to assess the potential risk posed by metals in marine sediments. They were tested using several CRMs and applied to sediments from two Galician Rias (NW Spain); their SEM-AVS differences indicated no biological risk.
Show more [+] Less [-]Ingestion of marine debris by the White-chinned Petrel (Procellaria aequinoctialis): Is it increasing over time off southern Brazil? Full text
2017
Petry, Maria V. | Benemann, Victória R.F.
Seabirds are amongst the most affected organisms by plastic pollution worldwide. Ingestion of marine debris has been reported in at least 122 species, and owing to the increasing global production and persistence of these anthropogenic materials within the marine environment, it is expected to be a growing problem to the marine fauna. Here we report evidence of an increasing frequency in marine debris ingestion and a decrease in the amount of plastic pellets ingested by White-chinned Petrels attending south Brazilian waters during the last three decades. Future studies comprising large temporal scales and large sample sizes are needed to better understand the trends of marine debris ingestion by seabirds. We expect our findings to highlight the need for prevention policies and mitigation measures to reduce the amount of solid litter in the oceans.
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