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Spatial relations of mercury contents in Pike (Esox lucius) and sediments concentration of the Anzali wetland, along the southern shores of the Caspian Sea, Iran Texto completo
2014
Zamani-Ahmadmahmoodi, Rasool | Bakhtiari, Alireza Riyahi | Rodríguez Martín, José Antonio
Spatial relations of mercury contents in Pike (Esox lucius) and sediments concentration of the Anzali wetland, along the southern shores of the Caspian Sea, Iran Texto completo
2014
Zamani-Ahmadmahmoodi, Rasool | Bakhtiari, Alireza Riyahi | Rodríguez Martín, José Antonio
In recent decades, the Anzali wetland has been threatened and destroyed by environmental pollution from several sources. The purpose of this study was to determine the possible relationships between mercury concentrations in Pike and their respective sediments within the assumed multiple activity center scales of Pike (100, 250 and 500m in radius). To gain a better understanding spatial distribution pattern of Hg in sediments and to pursue the main purpose of this study, kriging (geostatistic spatial interpolation method) was applied. Poor relationships were found between mercury concentrations of Pike and sediments within the assumed multiple activity center scales of Pike. The mercury sediment influence diminished with the increasing radii of assumed activity centers. The results of the present study indicate that fish and sediment mercury concentrations in western parts of the Anzali wetland were low in comparison with the concentrations reported in the literature from other regions.
Mostrar más [+] Menos [-]Spatial relations of mercury contents in Pike (Esox lucius) and sediments concentration of the Anzali wetland, along the southern shores of the Caspian Sea, Iran Texto completo
2014
Zamani-Ahmadmahmoodi, R. | Bakhtiari, A. R. | Rodríguez Martín, José Antonio
In recent decades, the Anzali wetland has been threatened and destroyed by environmental pollution from several sources. The purpose of this study was to determine the possible relationships between mercury concentrations in Pike and their respective sediments within the assumed multiple activity center scales of Pike (100, 250 and 500. m in radius). To gain a better understanding spatial distribution pattern of Hg in sediments and to pursue the main purpose of this study, kriging (geostatistic spatial interpolation method) was applied. Poor relationships were found between mercury concentrations of Pike and sediments within the assumed multiple activity center scales of Pike. The mercury sediment influence diminished with the increasing radii of assumed activity centers. The results of the present study indicate that fish and sediment mercury concentrations in western parts of the Anzali wetland were low in comparison with the concentrations reported in the literature from other regions. © 2014 Elsevier Ltd.
Mostrar más [+] Menos [-]Seaweeds and plastic debris can influence the survival of faecal indicator organisms in beach environments Texto completo
2014
Quilliam, Richard S. | Jamieson, Julie | Oliver, David M.
Seaweeds and plastic debris can influence the survival of faecal indicator organisms in beach environments Texto completo
2014
Quilliam, Richard S. | Jamieson, Julie | Oliver, David M.
The revised Bathing Water Directive (rBWD) introduces more stringent standards for microbial water quality and promotes more pro-active management of the beach environment through the production of a bathing water profile (BWP). The aim of this study was to determine whether living seaweeds in the littoral zone are colonised by faecal indicator organisms (FIOs), and to quantify the survival dynamics of waterborne Escherichia coli in microcosms containing senescing seaweeds. Living seaweed (Fucus spiralis) was not associated with FIO colonisation, although could be providing a protected environment in the underlying sand. Senescing seaweeds enhanced waterborne E. coli survival compared to plastic debris, with the brown seaweed Laminaria saccharina facilitating greater E. coli persistence than either Chondrus crispus or Ulva lactuca. This has important implications for FIO survival on bathing beaches as the majority of beach-cast biomass is composed of brown seaweeds, which could support significant levels of FIOs.
Mostrar más [+] Menos [-]Seaweeds and plastic debris can influence the survival of faecal indicator organisms in beach environments Texto completo
2014
Quilliam, Richard | Jamieson, Julie | Oliver, David | Biological and Environmental Sciences | University of Stirling | Biological and Environmental Sciences | 0000-0001-7020-4410 | 0000-0002-6200-562X
The revised Bathing Water Directive (rBWD) introduces more stringent standards for microbial water quality and promotes more pro-active management of the beach environment through the production of a bathing water profile (BWP). The aim of this study was to determine whether living seaweeds in the littoral zone are colonised by faecal indicator organisms (FIOs), and to quantify the survival dynamics of waterborne Escherichia coli in microcosms containing senescing seaweeds. Living seaweed (Fucus spiralis) was not associated with FIO colonisation, although could be providing a protected environment in the underlying sand. Senescing seaweeds enhanced waterborne E. coli survival compared to plastic debris, with the brown seaweed Laminaria saccharina facilitating greater E. coli persistence than either Chondrus crispus or Ulva lactuca. This has important implications for FIO survival on bathing beaches as the majority of beach-cast biomass is composed of brown seaweeds, which could support significant levels of FIOs.
Mostrar más [+] Menos [-]Ecological effects of contaminated sediments following a decade of no industrial effluents emissions: The Sediment Quality Triad approach Texto completo
2014
Lopes, Marta Lobão | Rodrigues, Ana Maria | Quintino, Victor
Ecological effects of contaminated sediments following a decade of no industrial effluents emissions: The Sediment Quality Triad approach Texto completo
2014
Lopes, Marta Lobão | Rodrigues, Ana Maria | Quintino, Victor
Sediments contaminated by industrial effluents a decade after the emissions were stopped were statistically compared to sediments from reference channels, using the Sediment Quality Triad approach. The metals and metalloid concentrations, mainly Hg and As, increased towards the upper part of a contaminated channel, where the industrial discharge was located. A bioaccumulation assay with Scrobicularia plana showed the highest bioaccumulation and mortality in the most contaminated sediments and bioaccumulation strongly correlated with the sediments metals and metalloid concentrations. The resident macroinvertebrate community also showed significant differences between the contaminated and reference channels, in the upper areas, where the community was most affected. All three elements of the quality triad rejected the null hypothesis and indicated that despite the emissions ceasing in 2004, sediments remain contaminated by high levels of metals and metalloid, leading to bioaccumulation and with severe community level consequences.
Mostrar más [+] Menos [-]Ecological effects of contaminated sediments following a decade of no industrial effluents emissions: the Sediment Quality Triad approach Texto completo
1000
Lopes, Marta Lobão | Rodrigues, Ana Maria | Quintino, Victor
Sediments contaminated by industrial effluents a decade after the emissions were stopped were statistically compared to sediments from reference channels, using the Sediment Quality Triad approach. The metals and metalloid concentrations, mainly Hg and As, increased towards the upper part of a contaminated channel, where the industrial discharge was located. A bioaccumulation assay with Scrobicularia plana showed the highest bioaccumulation and mortality in the most contaminated sediments and bioaccumulation strongly correlated with the sediments metals and metalloid concentrations. The resident macroinvertebrate community also showed significant differences between the contaminated and reference channels, in the upper areas, where the community was most affected. All three elements of the quality triad rejected the null hypothesis and indicated that despite the emissions ceasing in 2004, sediments remain contaminated by high levels of metals and metalloid, leading to bioaccumulation and with severe community level consequences.
Mostrar más [+] Menos [-]Salinity fluctuation of the brine discharge affects growth and survival of the seagrass Cymodocea nodosa Texto completo
2014
Garrote-Moreno, A. | Fernández-Torquemada, Y. | Sánchez-Lizaso, J.L.
Salinity fluctuation of the brine discharge affects growth and survival of the seagrass Cymodocea nodosa Texto completo
2014
Garrote-Moreno, A. | Fernández-Torquemada, Y. | Sánchez-Lizaso, J.L.
The increase of seawater desalination plants may affect seagrasses as a result of its hypersaline effluents. There are some studies on the salinity tolerance of seagrasses under controlled laboratory conditions, but few have been done in situ. To this end, Cymodocea nodosa shoots were placed during one month at four localities: two close to a brine discharge; and the other two not affected by the discharge, and this experiment was repeated four times. The results obtained showed a decrease in growth and an increased mortality at the localities affected by the brine discharge. An increase was detected in the percentage of horizontal shoots in respect to vertical shoots at the impacted localities. It is probably that not only the average salinity, but also the constant salinity fluctuations and slightly higher temperatures associated with the brine that may have caused physiological stress thus reducing C. nodosa growth and survival.
Mostrar más [+] Menos [-]Salinity fluctuation of the brine discharge affects growth and survival of the seagrass Cymodocea nodosa Texto completo
2014
Garrote-Moreno, Aurora | Fernández-Torquemada, Yolanda | Sánchez-Lizaso, José Luis | Fernández-Torquemada, Yolanda | Sánchez-Lizaso, José Luis | Universidad de Alicante. Departamento de Ciencias del Mar y Biología Aplicada | Biología Marina | Recursos Hídricos y Desarrollo Sostenible
The increase of seawater desalination plants may affect seagrasses as a result of its hypersaline effluents. There are some studies on the salinity tolerance of seagrasses under controlled laboratory conditions, but few have been done in situ. To this end, Cymodocea nodosa shoots were placed during one month at four localities: two close to a brine discharge; and the other two not affected by the discharge, and this experiment was repeated four times. The results obtained showed a decrease in growth and an increased mortality at the localities affected by the brine discharge. An increase was detected in the percentage of horizontal shoots in respect to vertical shoots at the impacted localities. It is probably that not only the average salinity, but also the constant salinity fluctuations and slightly higher temperatures associated with the brine that may have caused physiological stress thus reducing C. nodosa growth and survival. | This research was financed by a grant of University of Alicante and by an ACUAMED contract.
Mostrar más [+] Menos [-]Impact of sea-level rise and coral mortality on the wave dynamics and wave forces on barrier reefs Texto completo
2014
Baldock, T.E. | Golshani, A. | Callaghan, DP | Saunders, M.I. | Mumby, P.J.
A one-dimensional wave model was used to investigate the reef top wave dynamics across a large suite of idealized reef-lagoon profiles, representing barrier coral reef systems under different sea-level rise (SLR) scenarios. The modeling shows that the impacts of SLR vary spatially and are strongly influenced by the bathymetry of the reef and coral type. A complex response occurs for the wave orbital velocity and forces on corals, such that the changes in the wave dynamics vary reef by reef. Different wave loading regimes on massive and branching corals also leads to contrasting impacts from SLR. For many reef bathymetries, wave orbital velocities increase with SLR and cyclonic wave forces are reduced for certain coral species. These changes may be beneficial to coral health and colony resilience and imply that predicting SLR impacts on coral reefs requires careful consideration of the reef bathymetry and the mix of coral species.
Mostrar más [+] Menos [-]Field experiments on remediation of coastal sediments using granulated coal ash Texto completo
2014
Kim, Kyunghoi | Hibino, Tadashi | Yamamoto, Tamiji | Hayakawa, Shinjiro | Mito, Yugo | Nakamoto, Kenji | Lee, In-Cheol
Field experiments were carried out to evaluate the effect of Granulated Coal Ash (GCA) on remediation of coastal sediments in terms of removing phosphates and hydrogen sulfide. Phosphate concentrations in the sediment were kept below 0.2mg/l after the application of GCA, whereas those in the control sites increased up to 1.0mg/l. The concentration of hydrogen sulfide in the sediment was maintained at almost zero in the experimental sites (GCA application sites) for over one year, whereas it ranged 0.1–2.4mgSL−1 in control sites. Meanwhile, individual number of benthos increased in the experimental sites by several orders of magnitude compared to the control sites. The major process involved in hydrogen sulfide removal by GCA was thought to be the increase in pH, which suppresses hydrogen sulfide formation. From our findings, we concluded that GCA is an effective material for remediating organically enriched coastal sediment.
Mostrar más [+] Menos [-]Occurrence and distribution of phthalate esters in riverine sediments from the Pearl River Delta region, South China Texto completo
2014
Liu, Hong | Cui, Kunyan | Zeng, Feng | Chen, Lixuan | Cheng, Yating | Li, Huiru | Li, Shuocong | Zhou, Xi | Zhu, Fang | Ouyang, Gangfeng | Luan, Tiangang | Zeng, Zunxiang
Sixty-eight sediment samples collected from Dongjiang River, Xijiang River, Beijiang River and Zhujiang River in the Pearl River Delta (PRD) region, Southern China, were analyzed for 16 phthalate esters (PAEs). PAEs were detected in all riverine sediments analyzed, which indicate that PAEs are ubiquitous environmental contaminants. The Σ16PAEs concentrations in riverine sediments in the PRD region ranged from 0.567 to 47.3μgg−1 dry weight (dw), with the mean and median concentrations of 5.34μgg−1dw and 2.15μgg−1dw, respectively. Elevated PAEs concentrations in riverine sediments in the PRD region were found in the highly urbanized and industrialized areas. Of the 16 PAEs, diisobutyl phthalate (DiBP), di-n-butyl phthalate (DnBP) and di(2-ethylhexyl) phthalate (DEHP) dominated the PAEs, with the mean and median concentrations of 1.12μgg−1dw, 0.420μgg−1dw and 3.72μgg−1dw, and 0.429μgg−1dw, 0.152μgg−1dw and 1.55μgg−1dw, respectively, and accounted for 94.2–99.7% of the Σ16PAEs concentrations. Influenced by local sources and the properties of PAEs, a gradient trend of concentrations and a fractionation of composition from more to less industrialized and urbanized areas were discovered. As compared to the results from other studies, the riverine sediments in the PRD region were severely contaminated with PAEs. Information about PAEs contamination status and its effect on the aquatic organisms in the PRD region may deserve further attention.
Mostrar más [+] Menos [-]A novel best practices approach: The MARLISCO case Texto completo
2014
Loizidou, Xenia I. | Loizides, Michael I. | Orthodoxou, Demetra L.
Research that was undertaken to identify and evaluate best practices that can effectively minimise the amount of marine litter in European Seas is presented. Best practices were approached in a novel way that aimed to maximise the impact and added value of the FP7-funded project MARLISCO. The practices served as a tool to enhance the active participation and build capacity in key actors through the implementation of the innovative, dedicatedly-developed decision support tool, DeCyDe-4-Marlisco.This paper also presents the key ‘preference’ attributes of successful marine litter management practices and provides a snapshot of the key characteristics of the recorded best practices as a means of helping the reader, and particularly decision makers, recognise what would make their marine litter management efforts more successful.
Mostrar más [+] Menos [-]Lost opportunities: Coral recruitment does not translate to reef recovery in the Florida Keys Texto completo
2014
van Woesik, Robert | Scott, William J. | Aronson, Richard B.
We tested the hypothesis that the poor recovery of the coral populations on reefs in the Florida Keys is related to low coral recruitment. In the summer of 2011, we deployed 240 terracotta tiles at eight study sites in a balanced design: (i) among three depths; and (ii) between fished and unfished reefs. Corals recruited to ∼40% of the deployed tiles, with more corals settling on tiles on unfished reefs than on fished reefs. The apparent effect of protection was not a consequence of different densities of herbivorous fishes, but was more likely related to local hydrography and the tendency of the no-take reserves to act as larval sinks, particularly in the lower Florida Keys. There was a mismatch between the coral taxa that recruited and the adult coral assemblages, suggesting that recruits were arriving but not surviving to contribute to coral recovery.
Mostrar más [+] Menos [-]Community-level destruction of hard corals by the sea urchin Diadema setosum Texto completo
2014
Qiu, Jian-Wen | Lau, Dickey C.C. | Cheang, Chi-chiu | Chow, Wing-kuen
Sea urchins are common herbivores and bioeroders of coral ecosystems, but rarely have they been reported as corallivores. We determined the spatial pattern of hard coral damage due to corallivory and bioerosion by the sea urchin Diadema setosum Leske in Hong Kong waters. Coral damage was common at the northeastern sites, with 23.7 – 90.3% colonies being either collapsed or severely damaged with >25% tissue loss. Many genera of corals were impacted by the sea urchin but the damage was most obvious for the structure forming genus Platygyra. The percentage of severely damaged and collapsed coral had significant positive correlation with the abundance of D. setosum, which ranged from 0.01 to 5.2 individuals per coral head or 0.1 – 21.1 individuals m−2 across the study sites. Remedial management actions such as sea urchin removal are urgently needed to save these fringing coral communities.
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