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Simon Chenery - One of the best experts on this subject based on the ideXlab platform.

  • lability solubility and speciation of cd pb and zn in Alluvial Soils of the river trent catchment uk
    Environmental Science: Processes & Impacts, 2013
    Co-Authors: A M Tye, M T Izquierdo, Simon Chenery
    Abstract:

    Alluvial Soils can store a wide range of metal contaminants originating from point and diffuse sources. The biological health of these Soils is important as they act as an interface between terrestrial and aquatic environments, therefore playing an important role in maintaining the quality of surface waters. The aim of this work was to examine the lability, solubility and bioavailability of Pb, Zn and Cd in the top (0–15 cm) and sub soil (35–50 cm) of metal contaminated Alluvial Soils from the Trent catchment, U.K. Samples (n = 46) were collected from within 10 m of the river bank. Sources of contamination include historical mining, industry, sewage treatment works and energy production. Enrichment factors based on total metal concentrations showed that contamination in Soils declined with distance from the mining areas before rising again as a result of general urbanisation and identified point sources (e.g. river dredging activities). Pore waters were extracted and isotopic dilution and single extraction assays were undertaken on the Soils to assess the lability and solubility of the metals. Multi-element isotopic dilution assays were used to determine the labile pool or E-value of these metals in the soil. E-value concentrations were found to range between 0.5 and 14 mg kg−1, 11–350 mg kg−1 and 25–594 mg kg−1 for Cd, Pb and Zn, respectively. Comparison of the E-value assay with the EU standard extraction assay for trace element availability (0.05 M EDTA) showed that EDTA extractions generally over-estimated the E-value for Zn and Pb, with the difference being greater as contamination levels increased. Bioavailability of the metals was assessed by speciating the pore waters [MSol] using WHAM 7 to obtain estimates of free ion activities (M2+). Values of (M2+) were compared to published ‘median critical limits’ for Soils that estimate levels of protection for 95% of biological species. For each of the three metals, (M2+) was found to exceed these critical limits at some sites. Solubility of the metals are reported using Kd values expressed using both the total and E-value as the solid phase. Finally we examine the use of different metal pools (total, E-value, EDTA-extractable) and different measures of Fe oxide pools (total, free total, free amorphous), in predicting [MSol] concentrations and (M2+) using WHAM 7 in assemblage modelling mode. Overall best simultaneous model predictions for the three metals were obtained using the E-values. Larger over-estimates of [MSol] and (M2+) were produced using the EDTA and total metal pools whereas a better fitting in the prediction was obtained when models used either the total or the free total FeOx pools.

  • using lead isotopes to characterise their source lability and solubility in Alluvial Soils of the trent catchment uk abstract
    2013
    Co-Authors: A M Tye, M T Izquierdo, Simon Chenery
    Abstract:

    Fluvial environments are a major pathway for the dispersal of trace metal pollutants. A regional geochemical survey of the UK (G-BASE) revealed that Alluvial Soils of the Trent Catchment were enriched with Zn, Cd and Pb (Johnson et al . 2007). Sources of Pb contamination are likely to include petrol Pb, the Pb mines in the Peak district, industry and energy production. We investigated the source, lability and solubility of Pb using a range of isotope techniques in topSoils (0-15cm depth, n=27) and subSoils (35-50cm depth, n=19) taken within 10 m of the river bed (Izquierdo et al. 2012) throughout the course of the catchment of the River Trent. We measured Pb isotope ratios (206Pb/207Pb vs 208Pb/207Pb) in the whole soil, the labile Pb pool and in soil pore waters to enable us to examine the variation and proportion of Pb from different sources in each of these pools.

  • sources lability and solubility of pb in Alluvial Soils of the river trent catchment u k
    Science of The Total Environment, 2012
    Co-Authors: M T Izquierdo, A M Tye, Simon Chenery
    Abstract:

    Alluvial Soils are reservoirs of metal contaminants such as Pb that originate from many different sources and are integrated temporally and spatially through erosional and depositional processes. In this study the source, lability and solubility of Pb were examined in a range of Alluvial Soils from the middle and lower River Trent and its tributary the River Dove using Pb isotope apportionment and isotopic dilution. All samples were collected within 10 m of the river bank to represent the soil that is most likely to be remobilised during bank erosion. Paired samples were taken from the topsoil (0-15 cm) and subsoil (35-50 cm) to assess differences with depth. Lead concentrations in soil ranged from 43 to 1282 mg/kg. The lability of soil Pb varied between 9 and 56% of total metal concentration whilst Pb concentrations in pore water varied between 0.2 and 6.5 μg/L. There was little difference in the % Pb lability between paired top and sub Soils, possibly because soil characteristics such as pH, iron oxides and clay content were generally similar; a result of the recycling of eroded and deposited Soils within the river system. Soil pH was found to be negatively correlated with % Pb lability. Source apportionment using (206)Pb/(207)Pb and (208)Pb/(207)Pb ratios showed that the isotopic ratios of Pb in the total, labile and solution pools fitted along a mixing line between Broken Hill Type ('BHT') Pb, used as an additive in UK petrol, and the local coal/Southern Pennine ore Pb. Various anomalies were found in the Pb isotopes of the bankside Alluvial Soils which were explained by point source pollution. Statistically significant differences were found between (i) the isotopic composition of Pb in the total soil pool and the labile/solution pools and (ii) the isotopic composition of Pb in the labile and solution pools, suggesting an enrichment of recent non-Pennine sources of Pb entering the Soils in the labile and solution pools.

  • Lead lability in Alluvial Soils of the river Trent Catchment, U.K.
    2012
    Co-Authors: M. Izqueirdo, Andrew Tye, Simon Chenery
    Abstract:

    Fluvial environments are a major pathway for the dispersal of trace pollutants, whilst Alluvial Soils act as historical repositories of contaminants from different sources. The UK has an extensive Pb mining history in areas such as the Pennines. We investigated the spatial changes in sources and bioavailability of Pb in Alluvial Soils of the River Trent floodplain. We used Pb isotope geochemistry and isotope dilution methods to identify the sources and measure reactive pools of Pb in 38 paired topSoils (0-15 cm) and subSoils (35-50 cm). Lability of Soils varied between 9-56%, with little difference between top and subSoils as a result of recycling of river bank Soils. Soil pH was negatively correlated with lability. Source apportionment using 206Pb/207Pb and 208Pb/207Pb ratios showed that the isotopic ratios in the total, labile and pore water pools fitted along a mixing line between “Broken Hill Type (BHT)” Pb, used as additive before the phasing out of leaded petrol, and the Midlands coal/ Pennine ore Pb. Results showed that BHT Pb migrated downwards and reached 50% of total Pb in some sites. Statistically significant differences (P

Olivier Honnay - One of the best experts on this subject based on the ideXlab platform.

  • Assessing the potential of natural woody species regeneration for the conversion of Norway spruce plantations on Alluvial Soils
    Annals of Forest Science, 2004
    Co-Authors: Bruno Hérault, Daniel Thoen, Olivier Honnay
    Abstract:

    In the perspective of the conversion of Norway spruce plantations, there is a need for foresters to assess the potential of the natural woody species regeneration. We studied 50 Norway spruce plantations on Alluvial Soils throughout the Grand-duche de Luxembourg and compared the regeneration characteristics (species composition, spatial heterogeneity) with 42 riverine deciduous stands (the target communities). Within the Norway spruce plantations, Fraxinus excelsior and Acer pseudoplatanus were the main regenerating species, probably because of their very good dispersal abilities. Norway spruce seedlings were quasi-absent. Low Norway spruce densities and base- rich Soils (local factors) as well as proximity of riverine deciduous forests (regional factor) strongly favoured the regeneration of a suite of broad-leaved species. The thickness of Norway spruce litter did not appear to be a limiting factor, at least for large-seeded tree seedlings. The spatial heterogeneity of the woody regeneration was rather similar in coniferous and deciduous stands. We conclude that for the development of multifunctional forests, the spontaneous regeneration under low-dense Norway spruce stands on base-rich Soils provides a valuable starting point.

  • Assessing the potential of natural woody species regeneration for the conversion of Norway spruce plantations on Alluvial Soils
    Annals of Forest Science, 2004
    Co-Authors: Bruno Hérault, Daniel Thoen, Olivier Honnay
    Abstract:

    In the perspective of the conversion of Norway spruce plantations, there is a need for foresters to assess the potential of the natural woody species regeneration. We studied 50 Norway spruce plantations on Alluvial Soils throughout the Grand-duché de Luxembourg and compared the regeneration characteristics (species composition, spatial heterogeneity) with 42 riverine deciduous stands (the target communities). Within the Norway spruce plantations, Fraxinus excelsior and Acer pseudoplatanus were the main regenerating species, probably because of their very good dispersal abilities. Norway spruce seedlings were quasi-absent. Low Norway spruce densities and base-rich Soils (local factors) as well as proximity of riverine deciduous forests (regional factor) strongly favoured the regeneration of a suite of broad-leaved species. The thickness of Norway spruce litter did not appear to be a limiting factor, at least for large-seeded tree seedlings. The spatial heterogeneity of the woody regeneration was rather similar in coniferous and deciduous stands. We conclude that for the development of multifunctional forests, the spontaneous regeneration under low-dense Norway spruce stands on base-rich Soils provides a valuable starting point.

M T Izquierdo - One of the best experts on this subject based on the ideXlab platform.

  • lability solubility and speciation of cd pb and zn in Alluvial Soils of the river trent catchment uk
    Environmental Science: Processes & Impacts, 2013
    Co-Authors: A M Tye, M T Izquierdo, Simon Chenery
    Abstract:

    Alluvial Soils can store a wide range of metal contaminants originating from point and diffuse sources. The biological health of these Soils is important as they act as an interface between terrestrial and aquatic environments, therefore playing an important role in maintaining the quality of surface waters. The aim of this work was to examine the lability, solubility and bioavailability of Pb, Zn and Cd in the top (0–15 cm) and sub soil (35–50 cm) of metal contaminated Alluvial Soils from the Trent catchment, U.K. Samples (n = 46) were collected from within 10 m of the river bank. Sources of contamination include historical mining, industry, sewage treatment works and energy production. Enrichment factors based on total metal concentrations showed that contamination in Soils declined with distance from the mining areas before rising again as a result of general urbanisation and identified point sources (e.g. river dredging activities). Pore waters were extracted and isotopic dilution and single extraction assays were undertaken on the Soils to assess the lability and solubility of the metals. Multi-element isotopic dilution assays were used to determine the labile pool or E-value of these metals in the soil. E-value concentrations were found to range between 0.5 and 14 mg kg−1, 11–350 mg kg−1 and 25–594 mg kg−1 for Cd, Pb and Zn, respectively. Comparison of the E-value assay with the EU standard extraction assay for trace element availability (0.05 M EDTA) showed that EDTA extractions generally over-estimated the E-value for Zn and Pb, with the difference being greater as contamination levels increased. Bioavailability of the metals was assessed by speciating the pore waters [MSol] using WHAM 7 to obtain estimates of free ion activities (M2+). Values of (M2+) were compared to published ‘median critical limits’ for Soils that estimate levels of protection for 95% of biological species. For each of the three metals, (M2+) was found to exceed these critical limits at some sites. Solubility of the metals are reported using Kd values expressed using both the total and E-value as the solid phase. Finally we examine the use of different metal pools (total, E-value, EDTA-extractable) and different measures of Fe oxide pools (total, free total, free amorphous), in predicting [MSol] concentrations and (M2+) using WHAM 7 in assemblage modelling mode. Overall best simultaneous model predictions for the three metals were obtained using the E-values. Larger over-estimates of [MSol] and (M2+) were produced using the EDTA and total metal pools whereas a better fitting in the prediction was obtained when models used either the total or the free total FeOx pools.

  • using lead isotopes to characterise their source lability and solubility in Alluvial Soils of the trent catchment uk abstract
    2013
    Co-Authors: A M Tye, M T Izquierdo, Simon Chenery
    Abstract:

    Fluvial environments are a major pathway for the dispersal of trace metal pollutants. A regional geochemical survey of the UK (G-BASE) revealed that Alluvial Soils of the Trent Catchment were enriched with Zn, Cd and Pb (Johnson et al . 2007). Sources of Pb contamination are likely to include petrol Pb, the Pb mines in the Peak district, industry and energy production. We investigated the source, lability and solubility of Pb using a range of isotope techniques in topSoils (0-15cm depth, n=27) and subSoils (35-50cm depth, n=19) taken within 10 m of the river bed (Izquierdo et al. 2012) throughout the course of the catchment of the River Trent. We measured Pb isotope ratios (206Pb/207Pb vs 208Pb/207Pb) in the whole soil, the labile Pb pool and in soil pore waters to enable us to examine the variation and proportion of Pb from different sources in each of these pools.

  • sources lability and solubility of pb in Alluvial Soils of the river trent catchment u k
    Science of The Total Environment, 2012
    Co-Authors: M T Izquierdo, A M Tye, Simon Chenery
    Abstract:

    Alluvial Soils are reservoirs of metal contaminants such as Pb that originate from many different sources and are integrated temporally and spatially through erosional and depositional processes. In this study the source, lability and solubility of Pb were examined in a range of Alluvial Soils from the middle and lower River Trent and its tributary the River Dove using Pb isotope apportionment and isotopic dilution. All samples were collected within 10 m of the river bank to represent the soil that is most likely to be remobilised during bank erosion. Paired samples were taken from the topsoil (0-15 cm) and subsoil (35-50 cm) to assess differences with depth. Lead concentrations in soil ranged from 43 to 1282 mg/kg. The lability of soil Pb varied between 9 and 56% of total metal concentration whilst Pb concentrations in pore water varied between 0.2 and 6.5 μg/L. There was little difference in the % Pb lability between paired top and sub Soils, possibly because soil characteristics such as pH, iron oxides and clay content were generally similar; a result of the recycling of eroded and deposited Soils within the river system. Soil pH was found to be negatively correlated with % Pb lability. Source apportionment using (206)Pb/(207)Pb and (208)Pb/(207)Pb ratios showed that the isotopic ratios of Pb in the total, labile and solution pools fitted along a mixing line between Broken Hill Type ('BHT') Pb, used as an additive in UK petrol, and the local coal/Southern Pennine ore Pb. Various anomalies were found in the Pb isotopes of the bankside Alluvial Soils which were explained by point source pollution. Statistically significant differences were found between (i) the isotopic composition of Pb in the total soil pool and the labile/solution pools and (ii) the isotopic composition of Pb in the labile and solution pools, suggesting an enrichment of recent non-Pennine sources of Pb entering the Soils in the labile and solution pools.

Bruno Hérault - One of the best experts on this subject based on the ideXlab platform.

  • Assessing the potential of natural woody species regeneration for the conversion of Norway spruce plantations on Alluvial Soils
    Annals of Forest Science, 2004
    Co-Authors: Bruno Hérault, Daniel Thoen, Olivier Honnay
    Abstract:

    In the perspective of the conversion of Norway spruce plantations, there is a need for foresters to assess the potential of the natural woody species regeneration. We studied 50 Norway spruce plantations on Alluvial Soils throughout the Grand-duche de Luxembourg and compared the regeneration characteristics (species composition, spatial heterogeneity) with 42 riverine deciduous stands (the target communities). Within the Norway spruce plantations, Fraxinus excelsior and Acer pseudoplatanus were the main regenerating species, probably because of their very good dispersal abilities. Norway spruce seedlings were quasi-absent. Low Norway spruce densities and base- rich Soils (local factors) as well as proximity of riverine deciduous forests (regional factor) strongly favoured the regeneration of a suite of broad-leaved species. The thickness of Norway spruce litter did not appear to be a limiting factor, at least for large-seeded tree seedlings. The spatial heterogeneity of the woody regeneration was rather similar in coniferous and deciduous stands. We conclude that for the development of multifunctional forests, the spontaneous regeneration under low-dense Norway spruce stands on base-rich Soils provides a valuable starting point.

  • Assessing the potential of natural woody species regeneration for the conversion of Norway spruce plantations on Alluvial Soils
    Annals of Forest Science, 2004
    Co-Authors: Bruno Hérault, Daniel Thoen, Olivier Honnay
    Abstract:

    In the perspective of the conversion of Norway spruce plantations, there is a need for foresters to assess the potential of the natural woody species regeneration. We studied 50 Norway spruce plantations on Alluvial Soils throughout the Grand-duché de Luxembourg and compared the regeneration characteristics (species composition, spatial heterogeneity) with 42 riverine deciduous stands (the target communities). Within the Norway spruce plantations, Fraxinus excelsior and Acer pseudoplatanus were the main regenerating species, probably because of their very good dispersal abilities. Norway spruce seedlings were quasi-absent. Low Norway spruce densities and base-rich Soils (local factors) as well as proximity of riverine deciduous forests (regional factor) strongly favoured the regeneration of a suite of broad-leaved species. The thickness of Norway spruce litter did not appear to be a limiting factor, at least for large-seeded tree seedlings. The spatial heterogeneity of the woody regeneration was rather similar in coniferous and deciduous stands. We conclude that for the development of multifunctional forests, the spontaneous regeneration under low-dense Norway spruce stands on base-rich Soils provides a valuable starting point.

A M Tye - One of the best experts on this subject based on the ideXlab platform.

  • lability solubility and speciation of cd pb and zn in Alluvial Soils of the river trent catchment uk
    Environmental Science: Processes & Impacts, 2013
    Co-Authors: A M Tye, M T Izquierdo, Simon Chenery
    Abstract:

    Alluvial Soils can store a wide range of metal contaminants originating from point and diffuse sources. The biological health of these Soils is important as they act as an interface between terrestrial and aquatic environments, therefore playing an important role in maintaining the quality of surface waters. The aim of this work was to examine the lability, solubility and bioavailability of Pb, Zn and Cd in the top (0–15 cm) and sub soil (35–50 cm) of metal contaminated Alluvial Soils from the Trent catchment, U.K. Samples (n = 46) were collected from within 10 m of the river bank. Sources of contamination include historical mining, industry, sewage treatment works and energy production. Enrichment factors based on total metal concentrations showed that contamination in Soils declined with distance from the mining areas before rising again as a result of general urbanisation and identified point sources (e.g. river dredging activities). Pore waters were extracted and isotopic dilution and single extraction assays were undertaken on the Soils to assess the lability and solubility of the metals. Multi-element isotopic dilution assays were used to determine the labile pool or E-value of these metals in the soil. E-value concentrations were found to range between 0.5 and 14 mg kg−1, 11–350 mg kg−1 and 25–594 mg kg−1 for Cd, Pb and Zn, respectively. Comparison of the E-value assay with the EU standard extraction assay for trace element availability (0.05 M EDTA) showed that EDTA extractions generally over-estimated the E-value for Zn and Pb, with the difference being greater as contamination levels increased. Bioavailability of the metals was assessed by speciating the pore waters [MSol] using WHAM 7 to obtain estimates of free ion activities (M2+). Values of (M2+) were compared to published ‘median critical limits’ for Soils that estimate levels of protection for 95% of biological species. For each of the three metals, (M2+) was found to exceed these critical limits at some sites. Solubility of the metals are reported using Kd values expressed using both the total and E-value as the solid phase. Finally we examine the use of different metal pools (total, E-value, EDTA-extractable) and different measures of Fe oxide pools (total, free total, free amorphous), in predicting [MSol] concentrations and (M2+) using WHAM 7 in assemblage modelling mode. Overall best simultaneous model predictions for the three metals were obtained using the E-values. Larger over-estimates of [MSol] and (M2+) were produced using the EDTA and total metal pools whereas a better fitting in the prediction was obtained when models used either the total or the free total FeOx pools.

  • using lead isotopes to characterise their source lability and solubility in Alluvial Soils of the trent catchment uk abstract
    2013
    Co-Authors: A M Tye, M T Izquierdo, Simon Chenery
    Abstract:

    Fluvial environments are a major pathway for the dispersal of trace metal pollutants. A regional geochemical survey of the UK (G-BASE) revealed that Alluvial Soils of the Trent Catchment were enriched with Zn, Cd and Pb (Johnson et al . 2007). Sources of Pb contamination are likely to include petrol Pb, the Pb mines in the Peak district, industry and energy production. We investigated the source, lability and solubility of Pb using a range of isotope techniques in topSoils (0-15cm depth, n=27) and subSoils (35-50cm depth, n=19) taken within 10 m of the river bed (Izquierdo et al. 2012) throughout the course of the catchment of the River Trent. We measured Pb isotope ratios (206Pb/207Pb vs 208Pb/207Pb) in the whole soil, the labile Pb pool and in soil pore waters to enable us to examine the variation and proportion of Pb from different sources in each of these pools.

  • sources lability and solubility of pb in Alluvial Soils of the river trent catchment u k
    Science of The Total Environment, 2012
    Co-Authors: M T Izquierdo, A M Tye, Simon Chenery
    Abstract:

    Alluvial Soils are reservoirs of metal contaminants such as Pb that originate from many different sources and are integrated temporally and spatially through erosional and depositional processes. In this study the source, lability and solubility of Pb were examined in a range of Alluvial Soils from the middle and lower River Trent and its tributary the River Dove using Pb isotope apportionment and isotopic dilution. All samples were collected within 10 m of the river bank to represent the soil that is most likely to be remobilised during bank erosion. Paired samples were taken from the topsoil (0-15 cm) and subsoil (35-50 cm) to assess differences with depth. Lead concentrations in soil ranged from 43 to 1282 mg/kg. The lability of soil Pb varied between 9 and 56% of total metal concentration whilst Pb concentrations in pore water varied between 0.2 and 6.5 μg/L. There was little difference in the % Pb lability between paired top and sub Soils, possibly because soil characteristics such as pH, iron oxides and clay content were generally similar; a result of the recycling of eroded and deposited Soils within the river system. Soil pH was found to be negatively correlated with % Pb lability. Source apportionment using (206)Pb/(207)Pb and (208)Pb/(207)Pb ratios showed that the isotopic ratios of Pb in the total, labile and solution pools fitted along a mixing line between Broken Hill Type ('BHT') Pb, used as an additive in UK petrol, and the local coal/Southern Pennine ore Pb. Various anomalies were found in the Pb isotopes of the bankside Alluvial Soils which were explained by point source pollution. Statistically significant differences were found between (i) the isotopic composition of Pb in the total soil pool and the labile/solution pools and (ii) the isotopic composition of Pb in the labile and solution pools, suggesting an enrichment of recent non-Pennine sources of Pb entering the Soils in the labile and solution pools.