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Benthic habitat condition of the continental shelf surrounding oil and gas platforms in the Santa Barbara Channel, Southern California
2020
Gillett, David J. | Gilbane, Lisa | Schiff, Kenneth C.
The continental shelf of southern California is an important location for the extraction of petroleum and natural gas. Many platforms in the region have been operating for more than four decades and are being targeted for decommissioning. Information on the condition of surrounding habitats to the platforms will be important for regulators. The condition of sediments near (250 m–2 km) four active oil/gas platforms was evaluated with measures of macrobenthic infauna, toxicity, and chemical composition using standardized assessment indices and compared to that of equivalent locations across the region without platforms. Assessment scores indicated that the sediments surrounding the oil platforms were in a relatively good state, with reference-condition infauna, minimal levels of chemical exposure, and five instances (25% of samples) of low-level toxicity. Samples from around the oil platforms were in overall similar condition to the region, with slightly better condition infauna, nearly identical chemistry, and slightly worse toxicity.
显示更多 [+] 显示较少 [-]Visually-based alternatives to sediment environmental monitoring
2020
Simone, Michelle | Grant, Jon
Visually-based approaches using techniques such as sediment surface images as well as sediment profile imaging (SPI) have been applied previously in the assessment of benthic impacts of organic enrichment. New visually-based benthic health indices (VBH and Surface Index) that integrate various visual properties was developed for muddy and sandier sediments, respectively. Visual indices were compared to the existing sulfide-based thresholds often used in environmental monitoring programs (EMPs). We utilized both techniques as well as geochemical indicators of eutrophication to detect benthic impacts at shallow shellfish and finfish farms in Nova Scotia, Canada. The visual indices were able to capture a non-sulfidic anaerobic condition in the sediments missed by the current sulfide-based system. Our results indicate that as presently configured, the visual based index will provide a more stringent standard in the EMPs that currently rely on a sulfide-based classification system, and thus affect regulatory judgement.
显示更多 [+] 显示较少 [-]Are concentrations of pollutants in sharks, rays and skates (Elasmobranchii) a cause for concern? A systematic review
2020
Tiktak, Guuske P. | Butcher, Demi | Lawrence, Peter J. | Norrey, John | Bradley, L. (Lee) | Shaw, Kirsty | Preziosi, Richard | Megson, David
This review represents a comprehensive analysis on pollutants in elasmobranchs including meta-analysis on the most studied pollutants: mercury, cadmium, PCBs and DDTs, in muscle and liver tissue. Elasmobranchs are particularly vulnerable to pollutant exposure which may pose a risk to the organism as well as humans that consume elasmobranch products. The highest concentrations of pollutants were found in sharks occupying top trophic levels (Carcharhiniformes and Lamniformes). A human health risk assessment identified that children and adults consuming shark once a week are exposed to over three times more mercury than is recommended by the US EPA. This poses a risk to local fishing communities and international consumers of shark-based products, as well as those subject to the widespread mislabelling of elasmobranch products. Wider screening studies are recommended to determine the risk to elasmobranchs from emerging pollutants and more robust studies are recommended to assess the risks to human health.
显示更多 [+] 显示较少 [-]A baseline investigation of phytoplankton pigment composition in contrasting coastal ecosystems of north-western Bay of Bengal
2020
Srichandan, Suchismita | Baliarsingh, Sanjiba Kumar | Lotliker, Aneesh Anandrao | Prakash, Satya | Samanta, Alakes | Sahu, Kali Charan
A baseline investigation of the chromatographic characterization of phytoplankton pigments with complementing microscopy was conducted in Mahanadi estuary, Chilika lagoon, and coastal waters off Gopalpur along the east coast of India. Marker pigments specific to different phytoplankton groups have been discerned in these contrasting coastal ecosystems. A total of 16 phytoplankton pigments were identified. Irrespective of seasons, Chilika lagoon was characterized by a high concentration of zeaxanthin, indicating the predominance of picocyanobacteria. Zeaxanthin and fucoxanthin were the major diagnostic pigments in Mahanadi estuary during monsoon and other seasons, respectively. In coastal waters off Gopalpur, algal blooms resulted in a higher concentration of fucoxanthin during pre-monsoon and monsoon season. The pigment ratios were comparatively higher for Chilika lagoon than for Mahanadi estuary and off Gopalpur, irrespective of seasons. The present study highlights the advantages of the chromatography technique in identifying small-sized phytoplankton in coastal ecosystems in comparison to conventional microscopy.
显示更多 [+] 显示较少 [-]Sediment records of polybrominated diphenyl ethers (PBDEs) in Yangtze River Delta of Yangtze River in China
2020
Da, Chunnian | Wang, Ruwei | Xia, Linlin | Huang, Qing | Cai, Jiawei | Cai, Feixuan | Gao, Chongjing
The spatial and temporal distributions of polybrominated diphenyl ethers (PBDEs) were investigated in five sediment cores from the Yangtze River Delta of Yangtze River in China. The surficial concentrations of nine tri- through hepta-BDE congeners (Σ₉BDEs) and BDE209 were highest at urban sites S3 and S2, followed by rural site S1 and estuary sites S5 and S4, respectively, based on dry sediment weight. Both BDE209 and ∑₉BDE concentrations exponentially increased between 1990 and 2008. Commercial deca-BDE, penta-BDE, and octa-BDE products were likely PBDE sources in the study area. The relative abundances of BDE209 were higher in sediment cores from estuary than those from urban and rural locations, ascribing to the atmospheric transport from the adjacent densely populated northern and eastern coastal regions. This conclusion was further confirmed by the higher ratios of BDE47/BDE99 and BDE100/BDE99 in cores from the estuary than those from other locations.
显示更多 [+] 显示较少 [-]Legacy and current-use toxic contaminants in Pacific sand lance (Ammodytes personatus) from Puget Sound, Washington, USA
2020
Conn, K.E. | Liedtke, T.L. | Takesue, R.K. | Dinicola, R.S.
Forage fish are primary prey for seabirds, fish and marine mammals. Contaminant transfer and biomagnification of the toxic compounds measured in this study likely contribute to elevated levels in Puget Sound, Washington, salmon and killer whale tissues that could be sufficiently high to elicit adverse effects and hamper population recovery efforts. Polychlorinated biphenyls, polybrominated diphenyl ethers, chlorinated pesticides, polycyclic aromatic hydrocarbons, alkylphenols, and chlorinated paraffins were detected in all Pacific sand lance tissue samples generally below available health effect levels. Residual polycyclic aromatic hydrocarbon tissue concentrations near a former creosote site suggest ongoing contaminant exposure. Biomagnification calculations suggest that concentrations of polychlorinated biphenyls in some forage fish could result in predator tissue concentrations exceeding effect levels. The emerging contaminants alkylphenols and chlorinated paraffins are first reported here in Puget Sound forage fish, and their frequent detection, high production volumes and endocrine-disrupting properties highlight the need for further study.
显示更多 [+] 显示较少 [-]Functional diversity in the intertidal macrobenthic community at sewage-affected shores from Southwestern Atlantic
2020
Llanos, Elizabeth Noemi | Saracho Bottero, María Andrea | Jaubet, María Lourdes | Elías, Rodolfo | Garaffo, Griselda Valeria
Sewage pollution effect in a coastal area of the Southwestern Atlantic was tested, through the use of analysis of biological traits (BTA) and functional indices. Changes in the macrobenthic functional structure between the sewage outfall site and remote sites were observed. At the site in the discharge point, functional features related to organic enrichment were observed, such as deposit feeders, burrow dwellers and inhabitants of tubes, with low relative mobility and opportunistic species of the first and the second order. The functional indexes (Evenness, Dispersion, and Functional Specialization) showed the highest values in the sites far from the discharge point. The AMBI was positively correlated with FRic and negatively with FEve and FSpe. The opposite occurred with the M-AMBI. BTA and functional indices showed the changes that occurred due to sewage impacts in the benthic assemblages on rocky coasts in SW Atlantic.Sewage pollution effect in a coastal area of the Southwestern Atlantic was tested, through the use of functional diversity metrics (analysis of biological traits and functional indices). Biological samples were taken during spring and autumn (2015–2016), in four sampling sites distributed at different distances from the sewage outfall. Changes in the macrobenthic functional structure between the sewage outfall site and remote sites were observed. The functional indexes (Evenness, Dispersion, and Functional Specialization) showed the highest values in the sites far from the discharge point. Correlations between functional and environmental quality indices (AMBI and M-AMBI) were significant. The AMBI was positively correlated with Functional Richness and negatively with Functional Evenness and Functional Specialization. The opposite occurred with the M-AMBI. The analysis of biological traits and functional diversity indices represent informative and useful tools to describe the different aspects of sewage impacts in the benthic assemblages on rocky coasts in SW Atlantic. At the site in the discharge point, functional features related to organic enrichment were observed, such as deposit feeders, burrow dwellers and inhabitants of tubes, with low relative mobility and opportunistic species of the first and the second order.
显示更多 [+] 显示较少 [-]Membrane bioreactor and rapid sand filtration for the removal of microplastics in an urban wastewater treatment plant
2020
Bayo, Javier | López-Castellanos, Joaquín | Olmos, Sonia
This paper discusses about the role of two different wastewater treatment technologies in the abatement of microplastics (MPs) from the final effluent of an urban wastewater treatment plant (WWTP); i.e., membrane bioreactor technology (MBR) and rapid sand filtration (RSF). For this purpose, a WWTP with these two technologies was monitored for 18 months. The average microplastic concentration was 4.40 ± 1.01 MP L⁻¹ for the influent, 0.92 ± 0.21 MP L⁻¹ for MBR, and 1.08 ± 0.28 MP L⁻¹ for RSF, without statistically significant differences for MPs removal between both technologies (F-test = 0.195, p = 0.661). The main MP forms isolated in our study were fibers (1.34 ± 0.23 items L⁻¹), followed by films (0.59 ± 0.24 items L⁻¹), fragments (0.20 ± 0.09 items L⁻¹), and beads (0.02 ± 0.01 items L⁻¹). All of them probed to be statistically significant reduced after both technologies, but without statistically significant differences between them. The MP removal efficiency was 79.01% and 75.49% for MBR and RSF, respectively, although higher for microplastic particulate forms (MPPs), 98.83% and 95.53%, than for fibers, 57.65% and 53.83% for MBR and RSF, respectively, displaying a selective removal of particulate forms against microfibers. Fourteen different plastic polymers were identified in the influent, only persisting low-density polyethylene (LDPE), nylon (NYL), and polyvinyl (PV) in RSF effluent, and melamine (MUF) after MBR treatment. The MP size ranged from 210 μm, corresponding to NYL fragment form in the influent, to 6.3 mm, corresponding to a red microfiber also from the influent. The maximum MP average size significantly decreased from MBR (1.39 ± 0.15 mm), to RSF (1.15 ± 0.08 mm) and influent (1.05 ± 0.05 mm) (F-test = 4.014, p = 0.019), exhibiting the fiber selection carried out by these advanced technologies for wastewater treatment.
显示更多 [+] 显示较少 [-]Performance trends of environmental management in European ports
2020
Puig, Martí | Raptis, Sotiris | Wooldridge, Chris | Darbra, R.M.
This paper presents the current status and trends over time in the environmental situation of European ports, based on the results of a wide representation of EcoPorts members (90 ports). All the information presented in this research comes from the Self-Diagnosis Method (SDM), a concise checklist managed by European Sea Ports Organisation (ESPO), against which ports can self-assess their environmental management. The results provide data on a total number of 54 indicators, being the existence of an inventory of environmental legislation the indicator with the highest implementation (96,7%), followed by the existence of an environmental policy (95,7%). Waste is the environmental issue that is being more monitored by ports. Air quality continues as the top environmental priority, followed by energy consumption and noise. It is interesting to highlight the growing awareness of Climate change among ports as well as the increasing implementation of green initiatives in ports.
显示更多 [+] 显示较少 [-]Otolith fingerprints reveals potential pollution exposure of newly settled juvenile Sparus aurata
2020
Vrdoljak, Dario | Matić-Skoko, Sanja | Peharda, Melita | Uvanović, Hana | Markulin, Krešimir | Mertz-Kraus, Regina
Coastal ecosystems are increasingly threatened by a wide range of human activities. Fish otolith chemistry, by creating a unique specific signature, can be used as a natural tag for determining life stage dispersal, spatial connectivity and population structure. In this study, we tested whether differences in otolith composition among juveniles of gilthead sea bream, Sparus aurata, could enable their proper allocation to polluted areas based on higher concentrations of elements related to contaminants. Otoliths were embedded, sectioned and analysed by LA-ICP-MS in line scan mode. Multivariate analysis confirmed clear separation between sites and elements. Samples from the site under the strongest anthropogenic impact from industrial and agricultural river input were characterized by higher values of Pb/Ca and Zn/Ca. However, these relatively low values likely do not have a negative effect on S. aurata recruitment, though they could serve for identifying the contribution of polluted nurseries to stock dynamics.
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