The Experts below are selected from a list of 261 Experts worldwide ranked by ideXlab platform
Jorge E. S. Sarkis - One of the best experts on this subject based on the ideXlab platform.
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Influence of a Brazilian Sewage Outfall on the toxicity and contamination of adjacent sediments.
Marine pollution bulletin, 2005Co-Authors: Denis Moledo De Souza Abessa, R. Scott Carr, Bauer Rodarte De Figueredo Rachid, Eduinetty Ceci Pereira Moreira De Sousa, Marcos Antonio Hortelani, Jorge E. S. SarkisAbstract:The submarine Sewage Outfall of Santos (SSOS) is situated in the Santos Bay (Sao Paulo, Brazil) and is potentially a significant source of contaminants to the adjacent marine ecosystem. The present study aimed to assess the influence of SSOS on the sediment toxicity and contamination at Santos Bay. At the disposal site, sediments tended to be finer, organically richer and exhibited higher levels of surfactants and metals, sometimes exceeding the ''Threshold Effect Level'' values. The SSOS influence was more evident toward the East, where the sediments exhibited higher levels of TOC, total S and metals during the summer 2000 sampling cam- paign. Sediment toxicity to amphipods was consistently detected in four of the five stations studied. Amphipod survival tended to correlate negatively to Hg, total N and % mud. This work provides evidence that the SSOS discharge affects the quality of sed- iments from Santos Bay, and that control procedures are warranted. 2005 Elsevier Ltd. All rights reserved.
Federico Páez-osuna - One of the best experts on this subject based on the ideXlab platform.
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Selected trace metals in oysters (Crassostrea iridescens) and sediments from the discharge zone of the submarine Sewage Outfall in Mazatlán Bay (southeast Gulf of California): chemical fractions and bioaccumulation factors.
Environmental pollution (Barking Essex : 1987), 2001Co-Authors: Martín F. Soto-jiménez, Federico Páez-osuna, F. Morales-hernándezAbstract:Concentrations of Cd, Cr, Cu, Fe, Mn, Ni, Pb and Zn in the soft tissue of Crassostrea iridescens and the associated surface sediments (bulk and bioavailable metal concentrations) from an area influenced by a Sewage Outfall in Mazatlan Bay (southeast Gulf of California), were determined by atomic absorption spectrophotometry. Significant spatial differences in metal concentrations in both the bulk and bioavailable forms in the sediments were identified. An enrichment of Cu, Ni, Pb and Zn in sites located on a south–north transect was detected indicating a dominant influence of the Sewage Outfall toward the north. C. iridescens accumulated more Zn, Cu, Ni, Fe, Cd; and less Mn, Cr and Pb than were bioavailable in the sediments, as measured using conventional extraction analysis. The degree of enrichment and the bioavailable metal concentrations in the sediments of the south portion of Mazatlan Bay is discussed. The potential ability of C. iridescens as a biomonitor of metallic pollutants is postulated.
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Trace metals in two populations of the fireworm Eurythoe complanata from Mazatlán Bay: effect of body size on concentrations
Environmental Pollution, 1998Co-Authors: Nuria Méndez, Federico Páez-osunaAbstract:Trace metal concentrations (Cd, Co, Cr, Cu, Mn, Ni, Pb, Zn) were measured in two populations of the polychaete Eurythoe complanata collected in Mazatlan Bay (southeastern Gulf of California). With the exception of Cd, the trace metal concentrations fell within the ranges of other species of polychaetes collected elsewhere. The population of E. complanata collected from a site near to the Sewage Outfall (2.1 km) showed higher levels of Cu and Pb (following the same tendency of sediments) than the population from a site located 16 km away from the Sewage Outfall, where Cd worm concentrations were higher. Size-dependent relationships were observed for Cd, Ni, Pb and Zn only and the correlation was negative for the four elements. Evidently, this reveals different metabolic requirements in young (small) and old (larger) polychaetes.
M S Naumann - One of the best experts on this subject based on the ideXlab platform.
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Impacts of a high-discharge submarine Sewage Outfall on water quality in the coastal zone of Salvador (Bahia, Brazil).
Marine pollution bulletin, 2016Co-Authors: F Roth, G C Lessa, C Wild, R K P Kikuchi, M S NaumannAbstract:Carbon and nitrogen stable isotopic signatures of suspended particulate organic matter and seawater biological oxygen demand (BOD) were measured along a coastal transect during summer 2015 to investigate pollution impacts of a high-discharge submarine Sewage Outfall close to Salvador, Brazil. Impacts of untreated Sewage discharge were evident at the Outfall site by depleted δ(13)Corg and δ(15)N signatures and 4-fold increased BOD rates. Pollution effects of a Sewage plume were detectable for more than 6km downstream from the Outfall site, as seasonal wind- and tide-driven shelf hydrodynamics facilitated its advective transport into near-shore waters. There, Sewage pollution was detectable at recreational beaches by depleted stable isotope signatures and elevated BOD rates at high tides, suggesting high bacterial activity and increased infection risk by human pathogens. These findings indicate the urgent necessity for appropriate wastewater treatment in Salvador to achieve acceptable standards for released effluents and coastal zone water quality.
Dario Tarchi - One of the best experts on this subject based on the ideXlab platform.
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re assessing the extent of impact of malta s central mediterranean major Sewage Outfall using ers sar
Marine Pollution Bulletin, 2000Co-Authors: Victor Axiak, P Pavlakis, A.j Sieber, Dario TarchiAbstract:Abstract ERS SAR (Synthetic Aperture Radar) imagery has been used to re-assess the geographical extent of coastal area, which is exposed to environmental impact from Malta’s main Sewage Outfall at Wied Ghammieq. The Outfall presently discharges almost 80% of all the wastewater produced on the island, untreated into the sea. This is carried out through a 716 m long submarine Outfall equipped with a terminal diffuser. A number of past short-term field surveys had indicated that the geographical extent of the impacted area may extend up to 8 km south-east of the Outfall, especially when the submarine Outfall is malfunctioning. SAR imagery, reviewed in the present study, indicates that the geographical extent of the impacted coastline may be in fact three times longer than originally estimated. Support for this suggestion is presented through a review of bathing water quality of areas upstream and downstream to the present Outfall.
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Re-assessing the Extent of Impact of Malta’s (Central Mediterranean) Major Sewage Outfall Using ERS SAR
Marine Pollution Bulletin, 2000Co-Authors: Victor Axiak, P Pavlakis, A.j Sieber, Dario TarchiAbstract:Abstract ERS SAR (Synthetic Aperture Radar) imagery has been used to re-assess the geographical extent of coastal area, which is exposed to environmental impact from Malta’s main Sewage Outfall at Wied Ghammieq. The Outfall presently discharges almost 80% of all the wastewater produced on the island, untreated into the sea. This is carried out through a 716 m long submarine Outfall equipped with a terminal diffuser. A number of past short-term field surveys had indicated that the geographical extent of the impacted area may extend up to 8 km south-east of the Outfall, especially when the submarine Outfall is malfunctioning. SAR imagery, reviewed in the present study, indicates that the geographical extent of the impacted coastline may be in fact three times longer than originally estimated. Support for this suggestion is presented through a review of bathing water quality of areas upstream and downstream to the present Outfall.
Graciela S. Diniz - One of the best experts on this subject based on the ideXlab platform.
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Tissue Nitrogen and Phosphorus in Seaweeds in a Tropical Eutrophic Environment: What a Long-Term Study Tells Us
Journal of Applied Phycology, 2006Co-Authors: Sergio O. Lourenço, Elisabete Barbarino, Andyara Nascimento, Joana N. P. Freitas, Graciela S. DinizAbstract:Percentages of nitrogen and phosphorus in 10 species of seaweeds (6 green and 4 red algae) were monitored from 1997 to 2004 by seasonal sampling in Guanabara Bay, South-eastern Brazil. The species did not show consistent variations in tissue N , P and N : P that related to annual cycles. Throughout this study, higher percentages of tissue N and P were found in Bostrychia radicans and Grateloupia doryphora (red algae) and lower in Cladophora rupestris and Codium decorticatum (green algae). In November 1999, the Icaraí Submarine Sewage Outfall became operational, resulting in a reduction of visual pollution in the area and an improvement in the local quality of seawater for recreational use. Measurements of dissolved nutrients at the sampling site did not indicate significant changes in concentrations after the commissioning of the submarine Sewage Outfall; however, tissue P and N : P ratio of most of species were significantly lower than in the first two years of this survey. Variations in tissue nitrogen throughout this study were not significant, except for G. doryphora in some comparisons. Results show that seaweeds function very well as monitors of environmental changes in Guanabara Bay. Experimental data are needed to identify possible environmental processes which are promoting changes in chemical composition of the local seaweed populations.