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Long term development of Bathing Water Quality at the German Baltic coast: spatial patterns, problems and model simulations Full text
2018
Buer, Anna-Lucia | Gyraite, Greta | Wegener, Patrick | Lange, Xaver | Katarzyte, Marija | Hauk, Gerhard | Schernewski, Gerald
Bathing water quality plays a key role for public health, is highly important for recreational tourism and therefore monitored in the EU-Directive 2006/7/EC. To identify pollution hot spots, sources and impacts of the directive-change in 2006, including a change of indicator organisms, we evaluated monitoring data of the past 15 years, collected own data, determined survival rates of indicator organisms and applied hydrodynamic modelling in a micro-tidal-system.Due to higher survival rates under turbid conditions and restricted water exchange, shallow, eutrophic bays and lagoons are hot spots of microbial pollution. Rain events cause high microbial emission and distribution. Based on different decay rates, the ratio of E. coli to Enterococci can hint towards a pollution source. Including rain predictions, currents and winds, hydrodynamic models can then assess the daily risk of microbial pollution at each bathing site. They are an important tool to modify beach management and event-based monitoring.
Show more [+] Less [-]Sorption and desorption of selected pharmaceuticals by polyethylene microplastics Full text
2018
Razanajatovo, Roger Mamitiana | Ding, Jiannan | Zhang, Shanshan | Jiang, Hang | Zou, Hua
The aim of the present study was to evaluate the sorption and desorption of sulfamethoxazole (SMX), propranolol (PRP) and sertraline (SER) by polyethylene (PE) microplastics in water. After the 96 h mixture, the sorption percentages of pharmaceuticals on PE microplastics decreased according to the following order: SER (28.61%) > PRP (21.61%) > SMX (15.31%). The sorption kinetics were fitted well with the pseudo-second-order model. Both linear and Freundlich models were able to describe the sorption isotherm. The results suggest that the sorption process of the pharmaceuticals may be adequately described by their hydrophobicity and electrostatic interactions. The desorption results showed that 8% and 4% of PRP and SER, respectively, were released from the microplastics within 48 h, but the sorption of SMX was irreversible. The results indicate the potential risks of PRP and SER for bioaccumulation in aquatic organisms via ingestion of the microplastics in aquatic environments.
Show more [+] Less [-]Status of vulnerable Cystoseira populations along the Italian infralittoral fringe, and relationships with environmental and anthropogenic variables Full text
2018
Mancuso, F.P. | Strain, E.M.A. | Piccioni, E. | De Clerck, O. | Sarà, G. | Airoldi, L.
We analyzed the occurrence and status of infralittoral fringe populations of Cystoseira spp. (Fucales) at thirteen rocky sites around the Italian coastline, and explored the relationships with relevant environmental and anthropogenic variables. We found Cystoseira populations at 11 sites: most were scattered and comprised monospecific stands of C. compressa, and only 6 sites also supported sparse specimens of either C. amentacea var. stricta or C. brachycarpa. Coastal human population density, Chlorophyll a seawater concentrations, sea surface temperature, annual range of sea surface temperature and wave fetch explained most of the variation of the status of C. compressa. We hypothesize a generally unhealthy state of the Italian Cystoseira infralittoral fringe populations and identify multiple co-occurring anthropogenic stressors as the likely drivers of these poor conditions. Extensive baseline monitoring is needed to describe how Cystoseira populations are changing, and implement a management framework for the conservation of these valuable but vulnerable habitats.
Show more [+] Less [-]An evaluation of cumulative risks from offshore produced water discharges in the Bass Strait Full text
2018
Parkerton, T.F. | Bok, M. | Ireland, A.W. | Prosser, C.M.
Chemical analyses and toxicity testing using six marine species were used to characterize the hazard of produced waters (PW) to marine life from twelve Australian offshore platforms. Hazard data were used in conjunction with platform-specific plume discharge dilution and species sensitivity distribution modeling to estimate cumulative risks by calculating the multiple substance potentially affected fraction of species in the local marine environment. Results provided two independent lines of evidence demonstrating that cumulative risks to marine life from these discharges meet intended 95% species protection goals at the edge of the mixing zone. A limited number of PW constituents (hydrocarbons, sulphide and ammonia) appeared to dictate risk thereby informing management and providing a rationale for more targeted analyses in future monitoring studies. Based on these findings a tiered framework is proposed to foster consistent screening and potential refinement of cumulative risk evaluations for PW discharges.
Show more [+] Less [-]Sorption of three synthetic musks by microplastics Full text
2018
Zhang, Xiaojun | Zheng, Minggang | Wang, Ling | Lou, Yinghua | Shi, Lei | Jiang, Shujun
Microplastics and synthetic musks (SMs) are two typical organic pollutants in the marine environment. In this study, the sorption of three SMs to microplastics in a simulated seawater environment was examined. Tonalide (AHTN), musk xylene (MX), and musk ketone (MK) were the musks investigated, while polypropylene (PP) was used as the microplastic. It was found that the equilibrium sorption time was about 10h and the adsorption kinetics model conformed to a Lagergren adsorption model. The adsorption capacity increased with decreasing particle size. Adsorption reached a peak at 25°C, and the adsorption capacity was not sensitive to the concentration of sodium chloride. There is a need for more research and monitoring of microplastics in the marine environment due to their strong ability to absorb organic pollutants.
Show more [+] Less [-]Semivariance analysis and transinformation entropy for optimal redesigning of nutrients monitoring network in San Francisco bay Full text
2018
Boroumand, Amir | Rajaee, Taher | Masoumi, Fariborz
This paper introduces a Semivariance-Transinformation (S-T) based method for designing an optimum bay water nutrients monitoring network in San Francisco bay (S.F. bay), USA. Phosphorus and nitrogen are the most important nutrients that lead to eutrophic condition. The monthly phosphate and nitrate+nitrite data recorded during September 2006 to August 2015 was obtained over 14 active stations located at S.F. bay and was used in the research. Semivariance and discrete transinformation entropy have been applied to calculate the optimum range of the monitoring distance. The study indicated the ranges of 28 to 82 and 37 to 50km for the phosphate and nitrate+nitrite respectively. Useful information can be obtained from the monitoring network, if the monitoring distance is included in the mentioned intervals. The findings of the research introduce a new approach in the field of water quality monitoring networks design.
Show more [+] Less [-]Spatial distribution of marine litter along italian coastal areas in the Pelagos sanctuary (Ligurian Sea - NW Mediterranean Sea): A focus on natural and urban beaches Full text
2018
Giovacchini, Alice | Merlino, Silvia | Locritani, Marina | Stroobant, Mascha
Our paper will show data on quantity, typology, distribution of beach litter (Anthropogenic Marine Debris - AMD) within a coastal macroarea surrounding the Pelagos Sanctuary, an International Protected Area in the NW Mediterranean Sea. AMD Monitoring and characterisation have been performed by using SEACleaner Protocol: an adapted version of UNEP/IOC, OSPAR and EU guidelines. 11 beaches located in 5 different areas, have been monitored with a total amount of thirty three surveys, from January 2014 to December 2015, during different seasons. Three kinds of beaches have been considered: Natural (belonging to MPAs), Urbanized and Urban. A total of 34,027 items on a total area of 32,154 m2 have been removed and classified. Spatial difference in abundance and composition of AMDs - as well as beach environmental quality - has been detected. Natural sites, and particularly protected areas close to river mouths show a major density compared to other areas.
Show more [+] Less [-]Organophosphate flame retardants (OPFRs) in water and sediment: Occurrence, distribution, and hotspots of contamination of Lake Shihwa, Korea Full text
2018
Lee, Sunggyu | Cho, Hyun-Jin | Choi, Woosik | Moon, Hyo-Bang
Contamination by organophosphate flame retardants (OPFRs) is an emerging concern in aquatic environments. Concentrations of 18 OPFRs were measured in water and sediments collected from the artificial Lake Shihwa. OPFR concentrations in sediments measured in this study were the highest reported worldwide, implying severe OPFR contamination. The highest concentrations of OPFRs were found in creeks taken near industrial complexes, and OPFR concentrations decreased with increasing distance from creeks to inshore or offshore lake waters. On-going OPFR contamination by wastewater treatment plant (WWTP) discharge was evidenced by the clear decrease in OPFRs in water samples collected moving away from WWTP outfall. TBEP and TEP were dominant in water samples, while TDCPP and TCPP were dominant in sediment samples. Differences in contamination profiles with sample matrices are likely due to hydrophobicity of individual OPFRs. Non-parametric multidimensional scaling ordination showed that OPFR contamination was affected by pollution inflow and proximity to industrial complexes.
Show more [+] Less [-]Marine benthic communities affected by the Doce River (southwestern Atlantic): Baseline before a mining disaster Full text
2018
Matthews-Cascon, Helena | Bezerra, Luís Ernesto Arruda | Barroso, Cristiane Xerez | Rabay, Soraya Guimarães | Moreira, Ana Karla | Rocha, Valesca Paula | Soares, Marcelo de Oliveira
Prior to Brazil's worst environmental disaster, caused by a mining dam collapse, we had carried out a study of the marine benthic macrofauna (11–51 m depth) under the influence of the Doce River. Our results showed significant diversity, in which mollusks, polychaetes, and crustaceans had the highest frequency, density, and abundance, represented by 162 families in summer and 173 in winter. Our results suggested that richness, abundance, and diversity increase with distance from the coast. Furthermore, with increasing distance from the coast and river mouth, in addition to increasing depth, there was a differentiation in composition and abundance. Multivariate analyses showed depth, carbonate, and organic matter as important factors that explain variations in composition and diversity across the continental shelf. The results could provide an invaluable baseline for measuring the effects on shallow and mesophotic communities of one of the largest tailings dam failures worldwide.
Show more [+] Less [-]The distribution of and biodegradation impact on spilled oil in sediments from Dalian Bay, NE China Full text
2018
Yu, Xiaoguo | Zhang, Weiyan | Liu, Xing | Lei, Jijiang | Lin, Zhongsheng | Yao, Ziwei | Yao, Xuying | Jin, Xiaobing | Yang, Haili | Huang, Haiping
Three cores collected in the area of 16th July 2010 oil spill by box crab in May 2013 and July 2014 at the Dalian Bay have been geochemically characterized to investigate the fate of chemical components in sediments. The total organic carbon, extractable organic matter contents and biomarker compositions have been applied for the differentiation of alien organic matters from in situ ones and evaluation of the biodegradation impact. Multivariate statistical analysis suggests four groups of sediments. Except a few samples at deepest part of BQ050, majority samples have certain affinity with the spilled oil. The most contaminated sediments occur at site BQ050 and the spilled oil has migrated to 8–12 cm depth. The degree of contamination can be ranked by the similarity of molecular compositions with spilled oil. Variable biomarker components in sediment extracts were also altered by ongoing biodegradation.
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