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Algal δ¹⁵N values detect a wastewater effluent plume in nearshore and offshore surface waters and three-dimensionally model the plume across a coral reef on Maui, Hawai‘i, USA 全文
2012
Dailer, Meghan L. | Ramey, Hailey L. | Saephan, Stephanie | Smith, Celia M.
The coral reef at Kahekili, Maui is located ∼300m south of the Lahaina Wastewater Reclamation Facility which uses four Class V injection wells to dispose of 3–5million gallons of wastewater effluent daily. Prior research documented that the wastewater effluent percolates into the nearshore region of Kahekili. To determine if the wastewater effluent was detectable in the surface waters offshore, we used algal bioassays from the nearshore region to 100m offshore and throughout the water column from the surface to the benthos. These algal bioassays documented that significantly more wastewater effluent was detected in the surface rather than the benthic waters and allowed us to generate a three-dimensional model of the wastewater plume in the Kahekili coastal region. Samples located over freshwater seeps had the highest δ¹⁵N values (∼30–35‰) and the effluent was detected in surface samples 500m south and 100m offshore of the freshwater seeps (∼8–11‰).
显示更多 [+] 显示较少 [-]Monitoring temporal and spatial trends of legacy and emerging contaminants in marine environment: Results from the environmental specimen bank (es-BANK) of Ehime University, Japan 全文
2012
Tanabe, Shinsuke | Ramu, Karri
The Environmental Specimen Bank (es-BANK) for Global Monitoring at the Center for Marine Environmental Studies, Ehime University, Japan has more than four decades of practical experience in specimen banking. Over the years, es-BANK has archived specimens representing a wide range of environmental matrices, i.e. fishes, reptiles, birds, aquatic mammals, terrestrial mammals, human, soils, and sediments. The samples have been collected as part of the various monitoring programs conducted worldwide. The current review is a summary of selected studies conducted at the Center for Marine Environmental Studies, on temporal and spatial trends of legacy and emerging contaminants in the marine environment. One of the major conclusions drawn from the studies is that environmental problems are no more regional issues and, thus, environmental specimen banking should not be limited to national boundaries, but should have a global outlook.
显示更多 [+] 显示较少 [-]Isolation and characterization of two crude oil-degrading yeast strains, Yarrowia lipolytica PG-20 and PG-32, from the Persian Gulf 全文
2012
Hassanshahian, Mehdi | Tebyanian, Hamid | Cappello, Simone
Among six crude oil-degrading yeasts that were isolated from an oil-polluted area in the Persian Gulf, two yeast strains showed high degradation activity of aliphatic hydrocarbons. From an analysis of 18S rRNA sequences and biochemical characteristics, these strains were identified as Yarrowia lipolytica strains PG-20 and PG-32. Gas Chromatography (GC) analysis of the crude oil remaining in the culture medium after 1week at 30°C showed that the strains PG-20 and PG-32 degraded 68% and 58% of crude oil, respectively. The optimal growth condition and biodegradation of hydrocarbons was in ONR medium with an acidic pH (pH5). These two strains may degrade aliphatic hydrocarbons more efficiently than aromatic hydrocarbons, although strain PG-20 had better degradation than strain PG-32. The two Y. lipolytica strains reduce surface tension when cultured on hydrocarbon substrates (1% v/v). These strains showed a cell surface hydrophobicity higher than 70%. These results suggested that Y. lipolytica strains PG-20 and PG-32 have high crude oil degrading activity due to their high emulsifying activity and cell hydrophobicity. In conclusion, these yeast strains can be useful for the bioremediation process in the Persian Gulf and decreasing oil pollution in this marine ecosystem.
显示更多 [+] 显示较少 [-]Contaminant concentrations, biochemical and hematological biomarkers in blood of West Indian manatees Trichechus manatus from Brazil 全文
2012
Anzolin, D.G. | Sarkis, J.E.S. | Díaz, E. | Soares, D.G. | Serrano, I.L. | Borges, J.C.G. | Souto, A.S. | Taniguchi, S. | Montone, R.C. | Bainy, A.C.D. | Carvalho, P.S.M.
The West Indian manatee Trichechus manatus is threatened with extinction in Brazil, and this study focused on nondestructive blood samples analyzed for metals, polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs), as well as biochemical and hematological biomarkers. Studied manatees were kept at Projeto Peixe-Boi headquarters in Pernambuco State, and at two natural areas in estuaries where they are released to the wild. Manatees kept at the natural estuary in Paraiba State have blood concentrations of Al, Pb, Cd, Sn that are 11, 7, 8 and 23 times greater, respectively, than the concentrations found in blood of animals from the same species in Florida, USA. An inhibition of butyrylcholinesterase in manatees kept at the two reintroduction sites in Alagoas and Paraiba States indicated possible exposure of the animals to cholinesterase inhibitor insecticides. PCBs and OCPs were not detected. Results from this study will help delineate conservation efforts in the region.
显示更多 [+] 显示较少 [-]Evaluation for the ecological quality status of coastal waters in East China Sea using fuzzy integrated assessment method 全文
2012
Wu, H.Y. | Chen, K.L. | Chen, Z.H. | Chen, Q.H. | Qiu, Y.P. | Wu, J.C. | Zhang, J.F.
This research presented an evaluation for the ecological quality status (EcoQS) of three semi-enclosed coastal areas using fuzzy integrated assessment method (FIAM). With this method, the hierarchy structure was clarified by an index system of 11 indicators selected from biotic elements and physicochemical elements, and the weight vector of index system was calculated with Delphi-Analytic Hierarchy Process (AHP) procedure. Then, the FIAM was used to achieve an EcoQS assessment. As a result of assessment, most of the sampling stations demonstrated a clear gradient in EcoQS, ranging from high to poor status. Among the four statuses, high and good, owning a ratio of 55.9% and 26.5%, respectively, were two dominant statuses for three bays, especially for Sansha Bay and Luoyuan Bay. The assessment results were found consistent with the pressure information and parameters obtained at most stations. In addition, the sources of uncertainty in classification of EcoQS were also discussed.
显示更多 [+] 显示较少 [-]Fine sediment and nutrient dynamics related to particle size and floc formation in a Burdekin River flood plume, Australia 全文
2012
Bainbridge, Zoe T. | Wolanski, Eric | Álvarez-Romero, Jorge G. | Lewis, Stephen E. | Brodie, J. E. (Jon E.)
The extreme 2010–2011 wet season resulted in highly elevated Burdekin River discharge into the Great Barrier Reef lagoon for a period of 200days, resulting in a large flood plume extending >50km offshore and >100km north during peak conditions. Export of suspended sediment was dominated by clay and fine silt fractions and most sediment initially settled within ∼10km of the river mouth. Biologically-mediated flocculation of these particles enhanced deposition in the initial low salinity zone. Fine silt and clay particles and nutrients remaining in suspension, were carried as far as 100km northward from the mouth, binding with planktonic and transparent exopolymer particulate matter to form large floc aggregates (muddy marine snow). These aggregates, due to their sticky nature, likely pose a risk to benthic organisms e.g. coral and seagrass through smothering, and also by contributing to increased turbidity during wind-induced resuspension events.
显示更多 [+] 显示较少 [-]An assessment of an environmental gradient using coral geochemical records, Whitsunday Islands, Great Barrier Reef, Australia 全文
2012
Lewis, S.E. | Brodie, J.E. | McCulloch, M.T. | Mallela, J. | Jupiter, S.D. | Stuart Williams, H. | Lough, J.M. | Matson, E.G.
Coral cores were collected along an environmental and water quality gradient through the Whitsunday Island group, Great Barrier Reef (Australia), for trace element and stable isotope analysis. The primary aim of the study was to examine if this gradient could be detected in coral records and, if so, whether the gradient has changed over time with changing land use in the adjacent river catchments. Y/Ca was the trace element ratio which varied spatially across the gradient, with concentrations progressively decreasing away from the river mouths. The Ba/Ca and Y/Ca ratios were the only indicators of change in the gradient through time, increasing shortly after European settlement. The Mn/Ca ratio responded to local disturbance related to the construction of tourism infrastructure. Nitrogen isotope ratios showed no apparent trend over time. This study highlights the importance of site selection when using coral records to record regional environmental signals.
显示更多 [+] 显示较少 [-]Aspects of the digestive gland cells of the mussel Mytilus galloprovincialis, in relation to lysosomal enzymes, lipofuscin presence and shell size: Contribution in the assessment of marine pollution biomarkers 全文
2012
Raftopoulou, E.K. | Dimitriadis, V.K.
The present study investigates the histochemical localization of N-acetyl-β-hexozaminidase (Hex), acid phosphatase (AcP) and β-glucuronidase (β-Gus) in the digestive gland of mussels Mytilus galloprovincialis, as well as the clarification of suitable enzyme for biomarkers’ application dealing with lysosomes. The results show more intense and homogenous localization of Hex, in relation to AcP and β-Gus and, thus, Hex histochemistry is supported as more suitable procedure for the evaluation of “lysosomal membrane stability” and “morphometrical alterations of lysosomes”. The affection of lipofuscin granules on lysosomal enzymes’ activity is also discussed. Additionally, the present study examines the response of small- and large-sized mussels M. galloprovincialis by assessing the “lysosomal membrane stability”, “morphometrical alterations of lysosomes”, “lysosomal response index (LRI)” and “structural epithelial changes in digestive tubules”. The results indicate appreciable alterations of the above parameters in large-sized mussels, supporting their greater influence by the environmental factors, in relation to small-sized ones.
显示更多 [+] 显示较少 [-]Organotin levels in Nazaré canyon (west Iberian Margin, NE Atlantic) and adjacent coastal area 全文
2012
Sousa, Ana C.A. | Oliveira, Isabel B. | Laranjeiro, Filipe | Takahashi, Shin | Tanabe, Shinsuke | Cunha, Marina R. | Barroso, Carlos M.
Organotin levels in Nazaré canyon (west Iberian Margin, NE Atlantic) and adjacent coastal area 全文
2012
Sousa, Ana C.A. | Oliveira, Isabel B. | Laranjeiro, Filipe | Takahashi, Shin | Tanabe, Shinsuke | Cunha, Marina R. | Barroso, Carlos M.
Organotin compounds (OTs) are ubiquitous in the marine environment and high concentrations (μgg⁻¹ range) in sediments from different coastal areas around the world have been reported. However, few reports have described the OTs contamination status in the offshore and deep sea environment. This work investigated organotin levels in Nazaré canyon for the first time. Levels of monobutyltin (MBT), dibutyltin (DBT), tributyltin (TBT), diphenyltin (DPT), triphenyltin (TPT), dioctyltin (DOT) and trioctyltin (TOT) were quantified in sediment samples from the upper flanks of the canyon and from the adjacent coastal area. TBT levels detected in the canyon flanks are about two to three orders of magnitude lower than those found in the coastal area. Nevertheless, when quantifiable, TBT levels in the canyon samples were higher than the Environmental Assessment Criteria set for TBT in sediments by the OSPAR Commission indicating that at those locations negative ecological impacts are likely to occur.
显示更多 [+] 显示较少 [-]Organotin levels in Nazare canyon (west Iberian Margin, NE Atlantic) and adjacent coastal area 全文
1000 | 2012
Sousa, Ana C. A. | Oliveira, Isabel B. | Laranjeiro, Filipe | Takahashi, Shin | Tanabe, Shinsuke | Cunha, Marina R. | Barroso, Carlos M.
Organotin compounds (OTs) are ubiquitous in the marine environment and high concentrations (mu g g(-1) range) in sediments from different coastal areas around the world have been reported. However, few reports have described the OTs contamination status in the offshore and deep sea environment. This work investigated organotin levels in Nazare canyon for the first time. Levels of monobutyltin (MBT), dibutyltin (DBT), tributyltin (TBT), diphenyltin (DPT), triphenyltin (TPT), dioctyltin (DOT) and trioctyltin (TOT) were quantified in sediment samples from the upper flanks of the canyon and from the adjacent coastal area. TBT levels detected in the canyon flanks are about two to three orders of magnitude lower than those found in the coastal area. Nevertheless, when quantifiable. TBT levels in the canyon samples were higher than the Environmental Assessment Criteria set for TBT in sediments by the OSPAR Commission indicating that at those locations negative ecological impacts are likely to occur. (C) 2011 Elsevier Ltd. All rights reserved.
显示更多 [+] 显示较少 [-]Biomarker responses and genotoxicity in the mud snail (Bullacta exarata) as indicators of coastal contamination 全文
2012
An, Li-hui | Zheng, Bing-hui | Wang, Li-jing | Zhang, Yan-Qiang | Chen, Hao | Zhao, Xing-ru | Zhang, Lei | Lei, Kun
In the present study different biomarker responses and genotoxicity were determined in wild mud snails (Bullacta exarata) collected from 3 sampling sites in Bohai Bay in northeastern China, which is a region that is under considerable anthropogenic influence. Significant spatial variability of superoxide dismutase (SOD) and metallothionein (MT)-like proteins were recorded, while glutathione transferase (GST), catalase (CAT), and vitellin-like proteins (Vn’s) were not observed. Furthermore, genomic DNA that was amplified with 4 fluorescence-labeled primer pairs showed variable genetic distances among the 3 wild mud snail populations found in Bohai Bay, which may be correlated with differences in the types of environmental genotoxicants, such as heavy metals and polycyclic aromatic hydrocarbons. This multi-biomarker approach provided an improved understanding of the potential toxicological impact of contaminated sediments on benthic organisms.
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