T. Shimmield | The Scottish Association for Marine Science (original) (raw)
Papers by T. Shimmield
Twenty-eight metals and elements were measured in the muscle, liver, gills, bone and intestine of... more Twenty-eight metals and elements were measured in the muscle, liver, gills, bone and intestine of farmed seabass and gilthead seabream from four Mediterranean fish farms. The influence of fish species and the effect of environmental conditions on the metal accumulation in fish tissues was investigated. Most concentrations were lower in muscle and higher in liver and bone than in other body tissues. Seabass accumulates more elements in its tissues than seabream. Fish reared in coarse, oxic sites accumulate more elements with higher concentrations in muscle, bone and intestine and with lower concentrations in liver and gills than fish reared in silty, anoxic sites. This may be attributed to feed type and sediment properties. According to the metal pollution index, hazard quotient, selenium health benefit values, carcinogenic risk of arsenic, maximum safe consumption and the permitted limits, the consumption of both farmed species should be considered as safe for human health.
Food Chemistry 194: 659–670, 2016
Twenty-eight metals and elements were measured in the muscle, liver, gills, bone and intestine of... more Twenty-eight metals and elements were measured in the muscle, liver, gills, bone and intestine of farmed seabass and gilthead seabream from four Mediterranean fish farms. The influence of fish species and the effect of environmental conditions on the metal accumulation in fish tissues was investigated. Most concentrations were lower in muscle and higher in liver and bone than in other body tissues. Seabass accumulates more elements in its tissues than seabream. Fish reared in coarse, oxic sites accumulate more elements with higher concentrations in muscle, bone and intestine and with lower concentrations in liver and gills than fish reared in silty, anoxic sites. This may be attributed to feed type and sediment properties. According to the metal pollution index, hazard quotient, selenium health benefit values, carcinogenic risk of arsenic, maximum safe consumption and the permitted limits, the consumption of both farmed species should be considered as safe for human health.
Marine and Freshwater Research, 2005
Sagittal otoliths of European hake obtained from five geographic locations in the north-eastern A... more Sagittal otoliths of European hake obtained from five geographic locations in the north-eastern Atlantic and western Mediterranean were examined using laser ablation and inductively coupled plasma mass spectrometry. Otolith sections were analysed for the isotopes 24 Mg, 55 Mn, 66 Zn, 85 Rb, 86 Sr, 138 Ba and 208 Pb, measured relative to 43 Ca counts. These analyses considered only age 0 (core area) and ages 1 to 3. Age-related trends in otolith elemental composition were observed in hake from all areas, but were masked by variability between locations. Elemental concentrations generally decreased outside the core, with some increase at age 3. The composition of the otolith core was very distinct from that of the other growth increments. In the Mediterranean, part of this differentiation was a result of Mn, which was present in the core at high concentrations compared with the rest of the otolith. Mediterranean otoliths also had higher concentrations of Sr, Zn and Ba in the core. For most samples a similar trend was observed, although samples from one of the Mediterranean areas showed some differences, mainly in the concentrations of Mg and Sr. These results provide new empirical evidence of the variation in elemental concentrations across hake otoliths with age, at least throughout the first 3 years of life.
The Holocene, 2006
DOI: 10.1177/0959683606hl986rp 2006 16: 949 The Holocene and Tracy Shimmield ... W. Roland Gehrel... more DOI: 10.1177/0959683606hl986rp 2006 16: 949 The Holocene and Tracy Shimmield ... W. Roland Gehrels, William A. Marshall, Maria J. Gehrels, Gudrún Larsen, Jason R. Kirby, Jón Eiríksson, Jan Heinemeier Rapid sea-level rise in the North Atlantic Ocean since the first ...
Marine Geology, 2006
Two sediment cores from inner Loch Etive, a deep fjord basin on the west coast of Scotland, revea... more Two sediment cores from inner Loch Etive, a deep fjord basin on the west coast of Scotland, reveal a continuous sediment sequence spanning the last 10,000 yr. Benthic foraminiferal assemblages indicate that marine conditions prevailed in Loch Etive throughout the Holocene. However, changes in sediment grain size composition and magnetic susceptibility suggest that the strength and frequency of deep water
Journal of the Geological Society, 2000
The Barra Fan, located at the continental margin of NW Scotland, offers a unique possibility to r... more The Barra Fan, located at the continental margin of NW Scotland, offers a unique possibility to retrieve records of exceptional high resolution to obtain climate records on a centurymillennial timescale. We used a sedimentologicalgeochemical approach to examine the ...
Journal of Marine Systems, 2002
The Pomeranian Bight (southern Baltic Sea) is a mixing zone between waters of the Baltic Proper a... more The Pomeranian Bight (southern Baltic Sea) is a mixing zone between waters of the Baltic Proper and the river Oder, which drains a densely populated and highly industrialised catchment of central Europe. The bight is a nondepositional area, and all material produced in its water column, from erosion of strata at the seafloor and cliffs, and delivered by rivers, is transported near the seafloor to the depositional areas of the Arkona, Bornholm and Gdansk basins. In this contribution, we assess the origin, transformation and mass fluxes of material through the bight based on an integrated field study conducted in the period 1996 -1998. The transport mechanism is by wave-and current-induced resuspension and settling cycles, which effectively enrich organic-rich material and associated substances (organic pollutants, heavy metals) in deeper water; the estimated transport time is less than 6 months. The phases in which the material is transported are suspended matter in the water column, a particle-and aggregate-rich benthic boundary layer of < 1 m above the seafloor and a layer of fluffy material fed from the two other sources that covers the sandy near-shore sediments as a discrete phase; it collects up to 130 g m À 2 of particulate material after quiescent periods lasting several days. It is easily resuspended at shear velocities around 5 cm s À 1 and is recycled into the suspended matter and benthic boundary layer pools of material. In deeper waters ( > 20 m water depth), the fluffy layer is not readily distinguished from the underlying soft, organic-rich sediment and the change in physical and chemical properties is gradual. The organic matter passing through the coastal zone in the southern Baltic is unaffected by biological or chemical modifications in composition. We find no evidence for a preferential removal of nitrogen or phosphorus, even if the speciation of phosphorus changes from biological compounds to minerals. The compositional changes which we see, i.e., in the nitrogen isotopic composition and in trace metal concentrations, are mainly caused by dilution of the river signal. In the case of 0924-7963/02/$ -see front matter D 2002 Elsevier Science B.V. All rights reserved. PII: S 0 9 2 4 -7 9 6 3 ( 0 2 ) 0 0 1 2 7 -6
ICES Journal of Marine Science, 2006
Otolith chemistry: an aid to stock separation of Helicolenus dactylopterus (bluemouth) and Merluc... more Otolith chemistry: an aid to stock separation of Helicolenus dactylopterus (bluemouth) and Merluccius merluccius (European hake) in the Northeast Atlantic and Mediterranean. e ICES Journal of Marine Science, 63: 504e513.
Applied and Environmental Microbiology, 2008
In this study, we describe the isolation and characterization of a new exopolymer that exhibits h... more In this study, we describe the isolation and characterization of a new exopolymer that exhibits high emulsifying activities against a range of oil substrates and demonstrates a differential capacity to desorb various mono-, di-, and trivalent metal species from marine sediment under nonionic and seawater ionicstrength conditions. This polymer, PE12, was produced by a new isolate, Pseudoalteromonas sp. strain TG12 (accession number EF685033), during growth in a modified Zobell's 2216 medium amended with 1% glucose. Chemical and chromatographic analysis showed it to be a high-molecular-mass (>2,000 kDa) glycoprotein composed of carbohydrate (32.3%) and protein (8.2%). PE12 was notable in that it contained xylose as the major sugar component at unusually high levels (27.7%) not previously reported for a Pseudoalteromonas exopolymer. The polymer was shown to desorb various metal species from marine sediment-a function putatively conferred by its high content of uronic acids (28.7%). Seawater ionic strength (simulated using 0.6 M NaCl), however, caused a significant reduction in PE12's ability to desorb the sediment-adsorbed metals. These results demonstrate the importance of electrolytes, a physical parameter intrinsic of seawater, in influencing the interaction of microbial exopolymers with metal ions. In summary, PE12 may represent a new class of Pseudoalteromonas exopolymer with a potential for use in biotechnological applications as an emulsifying or metal-chelating agent. In addition to the biotechnological potential of these findings, the ecological aspects of this and related bacterial exopolymers in marine environments are also discussed.
Journal of Experimental Marine Biology and Ecology, 2003
Sediment and water can potentially be altered, chemically, physically and biologically as they ar... more Sediment and water can potentially be altered, chemically, physically and biologically as they are sampled at the seafloor, brought to the surface, processed and analysed. As a result, in situ observations of relatively undisturbed systems have become the goal of a growing body of scientists. 0022-0981/02/$ -see front matter D 2002 Elsevier Science B.V. All rights reserved. PII: S 0 0 2 2 -0 9 8 1 ( 0 2 ) 0 0 5 1 7 -8
Twenty-eight metals and elements were measured in the muscle, liver, gills, bone and intestine of... more Twenty-eight metals and elements were measured in the muscle, liver, gills, bone and intestine of farmed seabass and gilthead seabream from four Mediterranean fish farms. The influence of fish species and the effect of environmental conditions on the metal accumulation in fish tissues was investigated. Most concentrations were lower in muscle and higher in liver and bone than in other body tissues. Seabass accumulates more elements in its tissues than seabream. Fish reared in coarse, oxic sites accumulate more elements with higher concentrations in muscle, bone and intestine and with lower concentrations in liver and gills than fish reared in silty, anoxic sites. This may be attributed to feed type and sediment properties. According to the metal pollution index, hazard quotient, selenium health benefit values, carcinogenic risk of arsenic, maximum safe consumption and the permitted limits, the consumption of both farmed species should be considered as safe for human health.
Food Chemistry 194: 659–670, 2016
Twenty-eight metals and elements were measured in the muscle, liver, gills, bone and intestine of... more Twenty-eight metals and elements were measured in the muscle, liver, gills, bone and intestine of farmed seabass and gilthead seabream from four Mediterranean fish farms. The influence of fish species and the effect of environmental conditions on the metal accumulation in fish tissues was investigated. Most concentrations were lower in muscle and higher in liver and bone than in other body tissues. Seabass accumulates more elements in its tissues than seabream. Fish reared in coarse, oxic sites accumulate more elements with higher concentrations in muscle, bone and intestine and with lower concentrations in liver and gills than fish reared in silty, anoxic sites. This may be attributed to feed type and sediment properties. According to the metal pollution index, hazard quotient, selenium health benefit values, carcinogenic risk of arsenic, maximum safe consumption and the permitted limits, the consumption of both farmed species should be considered as safe for human health.
Marine and Freshwater Research, 2005
Sagittal otoliths of European hake obtained from five geographic locations in the north-eastern A... more Sagittal otoliths of European hake obtained from five geographic locations in the north-eastern Atlantic and western Mediterranean were examined using laser ablation and inductively coupled plasma mass spectrometry. Otolith sections were analysed for the isotopes 24 Mg, 55 Mn, 66 Zn, 85 Rb, 86 Sr, 138 Ba and 208 Pb, measured relative to 43 Ca counts. These analyses considered only age 0 (core area) and ages 1 to 3. Age-related trends in otolith elemental composition were observed in hake from all areas, but were masked by variability between locations. Elemental concentrations generally decreased outside the core, with some increase at age 3. The composition of the otolith core was very distinct from that of the other growth increments. In the Mediterranean, part of this differentiation was a result of Mn, which was present in the core at high concentrations compared with the rest of the otolith. Mediterranean otoliths also had higher concentrations of Sr, Zn and Ba in the core. For most samples a similar trend was observed, although samples from one of the Mediterranean areas showed some differences, mainly in the concentrations of Mg and Sr. These results provide new empirical evidence of the variation in elemental concentrations across hake otoliths with age, at least throughout the first 3 years of life.
The Holocene, 2006
DOI: 10.1177/0959683606hl986rp 2006 16: 949 The Holocene and Tracy Shimmield ... W. Roland Gehrel... more DOI: 10.1177/0959683606hl986rp 2006 16: 949 The Holocene and Tracy Shimmield ... W. Roland Gehrels, William A. Marshall, Maria J. Gehrels, Gudrún Larsen, Jason R. Kirby, Jón Eiríksson, Jan Heinemeier Rapid sea-level rise in the North Atlantic Ocean since the first ...
Marine Geology, 2006
Two sediment cores from inner Loch Etive, a deep fjord basin on the west coast of Scotland, revea... more Two sediment cores from inner Loch Etive, a deep fjord basin on the west coast of Scotland, reveal a continuous sediment sequence spanning the last 10,000 yr. Benthic foraminiferal assemblages indicate that marine conditions prevailed in Loch Etive throughout the Holocene. However, changes in sediment grain size composition and magnetic susceptibility suggest that the strength and frequency of deep water
Journal of the Geological Society, 2000
The Barra Fan, located at the continental margin of NW Scotland, offers a unique possibility to r... more The Barra Fan, located at the continental margin of NW Scotland, offers a unique possibility to retrieve records of exceptional high resolution to obtain climate records on a centurymillennial timescale. We used a sedimentologicalgeochemical approach to examine the ...
Journal of Marine Systems, 2002
The Pomeranian Bight (southern Baltic Sea) is a mixing zone between waters of the Baltic Proper a... more The Pomeranian Bight (southern Baltic Sea) is a mixing zone between waters of the Baltic Proper and the river Oder, which drains a densely populated and highly industrialised catchment of central Europe. The bight is a nondepositional area, and all material produced in its water column, from erosion of strata at the seafloor and cliffs, and delivered by rivers, is transported near the seafloor to the depositional areas of the Arkona, Bornholm and Gdansk basins. In this contribution, we assess the origin, transformation and mass fluxes of material through the bight based on an integrated field study conducted in the period 1996 -1998. The transport mechanism is by wave-and current-induced resuspension and settling cycles, which effectively enrich organic-rich material and associated substances (organic pollutants, heavy metals) in deeper water; the estimated transport time is less than 6 months. The phases in which the material is transported are suspended matter in the water column, a particle-and aggregate-rich benthic boundary layer of < 1 m above the seafloor and a layer of fluffy material fed from the two other sources that covers the sandy near-shore sediments as a discrete phase; it collects up to 130 g m À 2 of particulate material after quiescent periods lasting several days. It is easily resuspended at shear velocities around 5 cm s À 1 and is recycled into the suspended matter and benthic boundary layer pools of material. In deeper waters ( > 20 m water depth), the fluffy layer is not readily distinguished from the underlying soft, organic-rich sediment and the change in physical and chemical properties is gradual. The organic matter passing through the coastal zone in the southern Baltic is unaffected by biological or chemical modifications in composition. We find no evidence for a preferential removal of nitrogen or phosphorus, even if the speciation of phosphorus changes from biological compounds to minerals. The compositional changes which we see, i.e., in the nitrogen isotopic composition and in trace metal concentrations, are mainly caused by dilution of the river signal. In the case of 0924-7963/02/$ -see front matter D 2002 Elsevier Science B.V. All rights reserved. PII: S 0 9 2 4 -7 9 6 3 ( 0 2 ) 0 0 1 2 7 -6
ICES Journal of Marine Science, 2006
Otolith chemistry: an aid to stock separation of Helicolenus dactylopterus (bluemouth) and Merluc... more Otolith chemistry: an aid to stock separation of Helicolenus dactylopterus (bluemouth) and Merluccius merluccius (European hake) in the Northeast Atlantic and Mediterranean. e ICES Journal of Marine Science, 63: 504e513.
Applied and Environmental Microbiology, 2008
In this study, we describe the isolation and characterization of a new exopolymer that exhibits h... more In this study, we describe the isolation and characterization of a new exopolymer that exhibits high emulsifying activities against a range of oil substrates and demonstrates a differential capacity to desorb various mono-, di-, and trivalent metal species from marine sediment under nonionic and seawater ionicstrength conditions. This polymer, PE12, was produced by a new isolate, Pseudoalteromonas sp. strain TG12 (accession number EF685033), during growth in a modified Zobell's 2216 medium amended with 1% glucose. Chemical and chromatographic analysis showed it to be a high-molecular-mass (>2,000 kDa) glycoprotein composed of carbohydrate (32.3%) and protein (8.2%). PE12 was notable in that it contained xylose as the major sugar component at unusually high levels (27.7%) not previously reported for a Pseudoalteromonas exopolymer. The polymer was shown to desorb various metal species from marine sediment-a function putatively conferred by its high content of uronic acids (28.7%). Seawater ionic strength (simulated using 0.6 M NaCl), however, caused a significant reduction in PE12's ability to desorb the sediment-adsorbed metals. These results demonstrate the importance of electrolytes, a physical parameter intrinsic of seawater, in influencing the interaction of microbial exopolymers with metal ions. In summary, PE12 may represent a new class of Pseudoalteromonas exopolymer with a potential for use in biotechnological applications as an emulsifying or metal-chelating agent. In addition to the biotechnological potential of these findings, the ecological aspects of this and related bacterial exopolymers in marine environments are also discussed.
Journal of Experimental Marine Biology and Ecology, 2003
Sediment and water can potentially be altered, chemically, physically and biologically as they ar... more Sediment and water can potentially be altered, chemically, physically and biologically as they are sampled at the seafloor, brought to the surface, processed and analysed. As a result, in situ observations of relatively undisturbed systems have become the goal of a growing body of scientists. 0022-0981/02/$ -see front matter D 2002 Elsevier Science B.V. All rights reserved. PII: S 0 0 2 2 -0 9 8 1 ( 0 2 ) 0 0 5 1 7 -8