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G F Birch - One of the best experts on this subject based on the ideXlab platform.
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the use of Sedimentary metal data in predictive modelling of estuarine contamination assessment of environmental condition and pollutant source identification narrabeen lagoon sydney australia
Environmental Science and Pollution Research, 2020Co-Authors: G F Birch, J H LeeAbstract:Narrabeen Lagoon is recognized as an Intermittently Closed and Open Lake or Lagoon (ICOLL) and is the largest coastal lagoon (2.2 km2) in the Sydney metropolitan region. The catchment (53 km2) supports five major river systems, and land use comprises of 56% residential, 42% parkland and 2% light industry, commercial, hospital and education. An initial screening environmental assessment was undertaken using Sedimentary metals to determine the magnitude of anthropogenic change and level of ecological risk posed by these contaminants. Results illustrated an unusual example of an estuary significantly influenced by human-induced change, but exhibiting minimal ecological risk. This anomaly was due to high anthropogenic metal concentrations in the fine fraction of Surficial Sediment, which was considerably diluted by abundant metal-poor coarse material resulting in reduced adverse ecological impact for total Sediment. Predictive modelling to 2020 suggested that Pb concentrations will decline and Cu and Zn levels will increase slightly. Modelling of river discharge and analyses of fluvial Sedimentary metals suggested stormwater derived from the most urbanized catchments and a major roadway combined with poor flushing explained Surficial Sediment metal distributions in the lagoon.
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metal concentrations in sydney cockle anadara trapezia tissue and ambient Sediment in a highly modified estuary sydney estuary australia
Marine Pollution Bulletin, 2019Co-Authors: G F Birch, Y Shalem, Kimberly Lewtas, C H BesleyAbstract:The influence of Sedimentary metals on the cockle A. trapezia tissue was examined using a strong difference in Sedimentary metal concentrations in an embayment (Hen and Chicken Bay) highly contaminated in Cu and an adjacent cove (Iron Cove), strongly enriched in Cd, Cu, Pb and Zn within the heavily-urbanised Sydney estuary catchment (Australia). Statistically significant differences were recorded for cockle tissue metal concentrations between the study locations reflecting differences in Surficial Sediment metal concentrations. Low metal uptake was apparent in A. trapezia tissue, which were considerably less than background Sedimentary concentrations and was of low-risk for human consumption. Dissimilar bioconcentration of Cd, Cu, Pb and Zn was apparent in tissue of cockles (A. trapezia), prawns (Metapenaeus bennettae), mussels (Mytilus galloprovincialis) and oysters (Saccostrea glomerata), due possibly to different feeding patterns and biogeochemical conditions in bottom Sediments.
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metal concentrations in seagrass halophila ovalis tissue and ambient Sediment in a highly modified estuarine environment sydney estuary australia
Marine Pollution Bulletin, 2018Co-Authors: G F Birch, B M Cox, C H BesleyAbstract:Abstract Research into Sediment-seagrass tissue metal relationships has been undertaken in Sydney estuary due to the recognized role contamination plays in threats to seagrass health. Seagrass (Halophila ovalis) leaf tissue concentrations are elevated in Cu, Pb and Zn and contain the highest reported root Cr concentrations. Seagrass metal concentrations were significantly different between species H. ovalis and Zostera capricorni; between root and leaf tissue; and between sampling locations. Greatest tissue enrichment was for Pb, however metals were not enriched in seagrass relative to Surficial Sediment. Fine and total Sediment metal concentrations were temporally consistent between collection years 2013/15, whereas root tissue metals changed between years and sites and leaf metal contents were temporally inconsistent. Extractable metal concentrations in fine Sediment (
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the use of vintage Surficial Sediment data and Sedimentary cores to determine past and future trends in estuarine metal contamination sydney estuary australia
Science of The Total Environment, 2013Co-Authors: G F Birch, C H Chang, J H Lee, L J ChurchillAbstract:Abstract The objectives of the present investigation were to determine past trends in Sediment contamination and possibly predict future trends. Multiple vintages of Surficial Sediment metal data, from a quasi-decadal ‘Status and Trends’ programme, were used to provide large-scale spatial information on current status and temporal change. This information was augmented by Sediment cores, specifically located to verify surface Sediment data and to determine trends at major points of stormwater discharge. The data obtained indicate that Surficial Sediment metal concentrations have declined, since about the early 1990s, in extensive parts of the upper and central estuaries and have increased slightly in the lower estuary, due mainly to a down-estuary shift in industry and urbanisation. Declining Surficial Sediment metal concentrations is due to a movement of industry out of the catchment, especially from foreshore areas and the introduction of regulation, which prevent pollutants being discharged directly to the estuary. The major present-day source of metals is stormwater, with minor inputs from the main estuary channel into embayments and runoff from previously contaminated mainland sites. Modelled relaxation rates are optimistic as high metal concentrations in stormwater will slow predicted rates. Stormwater remediation should be the main managerial focus for this estuary. Multiple vintages of Surficial Sediment metal data covering the past 30 years, supplemented by Sedimentary core data, have allowed past and future contamination trends to be determined. This type of science-based information provides an important tool for strategic management of this iconic waterway.
Richard A Pickrill - One of the best experts on this subject based on the ideXlab platform.
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image based classification of multibeam sonar backscatter data for objective Surficial Sediment mapping of georges bank canada
Continental Shelf Research, 2011Co-Authors: Craig J Brown, B J Todd, Vladimir E Kostylev, Richard A PickrillAbstract:Abstract Developments in acoustic survey techniques, in particular multibeam sonar, have revolutionised the way we are able to image, map and understand the seabed environment. It is now cost effective to image large areas of the seafloor using these techniques, and the information from such surveys provides base line data from which thematic maps of the seabed environment, including maps of Surficial geology, can be derived when interpreted in conjunction with in-situ ground truthing data. Traditional methods for the interpretation of acoustic backscatter rely on experienced interpretation by eye of grey-scale images produced from the data. However, interpretation of data can be subjective, and new developments in semi-automated backscatter classification software offer an objective method of segmentation of acoustic backscatter data into acoustically similar regions, but are not yet well tested or accepted. A large multibeam sonar data set from Georges Bank, Canada, was classified using the backscatter classification software, QTC-Multiview. Data from 4800 km 2 of seabed were classified and results were compared with 110 ground truthing stations to assess the performance of the classification for geological discrimination. The relationship between backscatter metrics derived from the classification software and benthic geological characteristics were explored using statistical methods. Results suggest that image-based backscatter classification shows considerable promise for interpretation of multibeam sonar data for the production of geological maps.
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quaternary geology and Surficial Sediment processes browns bank scotian shelf based on multibeam bathymetry
Marine Geology, 1999Co-Authors: Brian J Todd, Gordon B J Fader, Robert C Courtney, Richard A PickrillAbstract:Abstract Browns Bank is located on the glaciated continental shelf off southern Nova Scotia. Geological mapping of Browns Bank is based on interpretation of multibeam bathymetric and backscatter data, in conjunction with 220 line km of seismic reflection profiles and sidescan sonograms, sea-floor Sediment samples and bottom photographs. The Fundian Moraine, part of the previously identified end moraine system on the continental shelf off Nova Scotia, is a prominent west–east, flat-topped, multi-lobate ridge identifiable in the multibeam bathymetric data and in geophysical records. The Fundian Moraine was subjected to erosion in the surf zone during sea-level rise in depths less than 100 m. A series of north–south, roughly parallel till ridges, continuous in the subsurface with the Fundian Moraine, is interpreted as interlobate moraines suggesting formation by a tidewater glacier. The Browns Bank Moraine, connected to the Fundian Moraine, is evidence of a newly identified grounded ice position farther seaward than the latter. Bedforms, including obstacle marks, comet marks, sand waves and megaripples, are evidence of a vigorous anticyclonic current pattern on Browns Bank. The combination of multibeam bathymetric imagery with high-resolution geoscientific information represents a powerful technique for sea-floor geological investigations.
C H Besley - One of the best experts on this subject based on the ideXlab platform.
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metal concentrations in sydney cockle anadara trapezia tissue and ambient Sediment in a highly modified estuary sydney estuary australia
Marine Pollution Bulletin, 2019Co-Authors: G F Birch, Y Shalem, Kimberly Lewtas, C H BesleyAbstract:The influence of Sedimentary metals on the cockle A. trapezia tissue was examined using a strong difference in Sedimentary metal concentrations in an embayment (Hen and Chicken Bay) highly contaminated in Cu and an adjacent cove (Iron Cove), strongly enriched in Cd, Cu, Pb and Zn within the heavily-urbanised Sydney estuary catchment (Australia). Statistically significant differences were recorded for cockle tissue metal concentrations between the study locations reflecting differences in Surficial Sediment metal concentrations. Low metal uptake was apparent in A. trapezia tissue, which were considerably less than background Sedimentary concentrations and was of low-risk for human consumption. Dissimilar bioconcentration of Cd, Cu, Pb and Zn was apparent in tissue of cockles (A. trapezia), prawns (Metapenaeus bennettae), mussels (Mytilus galloprovincialis) and oysters (Saccostrea glomerata), due possibly to different feeding patterns and biogeochemical conditions in bottom Sediments.
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metal concentrations in seagrass halophila ovalis tissue and ambient Sediment in a highly modified estuarine environment sydney estuary australia
Marine Pollution Bulletin, 2018Co-Authors: G F Birch, B M Cox, C H BesleyAbstract:Abstract Research into Sediment-seagrass tissue metal relationships has been undertaken in Sydney estuary due to the recognized role contamination plays in threats to seagrass health. Seagrass (Halophila ovalis) leaf tissue concentrations are elevated in Cu, Pb and Zn and contain the highest reported root Cr concentrations. Seagrass metal concentrations were significantly different between species H. ovalis and Zostera capricorni; between root and leaf tissue; and between sampling locations. Greatest tissue enrichment was for Pb, however metals were not enriched in seagrass relative to Surficial Sediment. Fine and total Sediment metal concentrations were temporally consistent between collection years 2013/15, whereas root tissue metals changed between years and sites and leaf metal contents were temporally inconsistent. Extractable metal concentrations in fine Sediment (
Charles Hemming - One of the best experts on this subject based on the ideXlab platform.
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effect of experimental technique on the determination of strontium distribution coefficients of a Surficial Sediment from the idaho national engineering laboratory idaho
Water Research, 1997Co-Authors: M.j. Liszewski, Jeffrey J Rosentreter, R L Bunde, Charles Hemming, John WelhanAbstract:Abstract The effect of experimental technique on strontium distribution coefficients ( K d 's) was determined as part of an investigation of strontium geochemical transport properties of Surficial Sediment from the Idaho National Engineering Laboratory, Idaho. The investigation was conducted by the U.S. Geological Survey and Idaho State University, in cooperation with the U.S. Department of Energy. Batch experiments were conducted to quantify the effect of different experimental techniques on experimentally derived strontium K d 's at a fixed pH of 8.0. Combinations of three variables were investigated: method of sample agitation (rotating-mixer and shaker table), ratio of the mass-of-Sediment to the volume-of-reaction-solution (1:2 and 1:20), and method of Sediment preparation (crushed and non-crushed). Strontium K d 's ranged from 11 to 23 mlg −1 among all three experimental variables examined. Strontium K d 's were bimodally grouped around 12 and 21 mlg −1 . Among the three experimental variables examined, the mass-to-volume ratio appeared to be the only one that could account for this bimodal distribution. The bimodal distribution of the derived strontium K d 's may occur because the two different mass-to-volume ratios represent different natural systems. The high mass-to-volume ratio of 1:2 models a natural system, such as an aquifer, in which there is an abundance of favorable sorption sites relative to the amount of strontium in solution. The low mass-to-volume ratio of 1:20 models a natural system, such as a stream, in which the relative amount of strontium in solution exceeds the favorable surface sorption site concentration. Except for low mass-to-volume ratios of non-crushed Sediment using a rotating mixer, the method of agitation and Sediment preparation appears to have little influence on derived strontium K d 's.
R L Bunde - One of the best experts on this subject based on the ideXlab platform.
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rate of strontium sorption and the effects of variable aqueous concentrations of sodium and potassium on strontium distribution coefficients of a Surficial Sediment at the idaho national engineering laboratory idaho
Environmental Earth Sciences, 1998Co-Authors: R L Bunde, Jeffrey J Rosentreter, M.j. LiszewskiAbstract:The rate of strontium sorption and the effects of variable aqueous concentrations of sodium and potassium on strontium sorption were measured as part of an investigation to determine strontium chemical transport properties of a Surficial Sediment at the Idaho National Engineering Laboratory (INEL), Idaho. Batch experimental techniques were used to determine the rate of strontium sorption and strontium distribution coefficients (Kds) between aqueous and solid phases. Rate experiments indicate that strontium in solution reached an apparent equilibrium with the Sediment in 26 h. Kds were derived using the linear isotherm model at initial sodium concentrations from 100 to 5,000 mg/l and initial potassium concentrations from 2 to 150 mg/l. Kds ranged from 56±2 to 62±3 ml/g at initial aqueous concentrations of sodium and potassium equal to or less than 300 and 150 mg/l, respectively. Kds ranged from 4.7±0.2 to 19±1 ml/g with initial aqueous concentrations of sodium between 1,000 and 5,000 mg/l. These data indicate that sodium concentrations greater than 300 mg/l in wastewater increase the availability of strontium for transport beneath waste disposal ponds at the INEL by decreasing strontium sorption on the Surficial Sediment. Wastewater concentrations of sodium and potassium less than 300 and 150 mg/l, respectively, have little effect on the availability of strontium for transport.
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effect of experimental technique on the determination of strontium distribution coefficients of a Surficial Sediment from the idaho national engineering laboratory idaho
Water Research, 1997Co-Authors: M.j. Liszewski, Jeffrey J Rosentreter, R L Bunde, Charles Hemming, John WelhanAbstract:Abstract The effect of experimental technique on strontium distribution coefficients ( K d 's) was determined as part of an investigation of strontium geochemical transport properties of Surficial Sediment from the Idaho National Engineering Laboratory, Idaho. The investigation was conducted by the U.S. Geological Survey and Idaho State University, in cooperation with the U.S. Department of Energy. Batch experiments were conducted to quantify the effect of different experimental techniques on experimentally derived strontium K d 's at a fixed pH of 8.0. Combinations of three variables were investigated: method of sample agitation (rotating-mixer and shaker table), ratio of the mass-of-Sediment to the volume-of-reaction-solution (1:2 and 1:20), and method of Sediment preparation (crushed and non-crushed). Strontium K d 's ranged from 11 to 23 mlg −1 among all three experimental variables examined. Strontium K d 's were bimodally grouped around 12 and 21 mlg −1 . Among the three experimental variables examined, the mass-to-volume ratio appeared to be the only one that could account for this bimodal distribution. The bimodal distribution of the derived strontium K d 's may occur because the two different mass-to-volume ratios represent different natural systems. The high mass-to-volume ratio of 1:2 models a natural system, such as an aquifer, in which there is an abundance of favorable sorption sites relative to the amount of strontium in solution. The low mass-to-volume ratio of 1:20 models a natural system, such as a stream, in which the relative amount of strontium in solution exceeds the favorable surface sorption site concentration. Except for low mass-to-volume ratios of non-crushed Sediment using a rotating mixer, the method of agitation and Sediment preparation appears to have little influence on derived strontium K d 's.
