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Christine Alewell - One of the best experts on this subject based on the ideXlab platform.

  • excess lead 210 and Plutonium 239 240 two suitable radiogenic soil erosion tracers for mountain grassland sites
    Environmental Research, 2018
    Co-Authors: Katrin Meusburger, Paolo Porto, Lionel Mabit, C La Spada, Laura Arata, Christine Alewell
    Abstract:

    Abstract The expected growing population and challenges associated with globalisation will increase local food and feed demands and enhance the pressure on local and regional upland soil resources. In light of these potential future developments it is necessary to define sustainable land use and tolerable soil loss rates with methods applicable and adapted to mountainous areas. Fallout-radionuclides (FRNs) are proven techniques to increase our knowledge about the status and resilience of agro-ecosystems. However, the use of the Caesium-137 ( 137 Cs) method is complicated in the European Alps due to its heterogeneous input and the timing of the Chernobyl fallout, which occurred during a few single rain events on partly snow covered ground. Other radioisotopic techniques have been proposed to overcome these limitations. The objective of this study is to evaluate the suitability of excess Lead-210 ( 210 Pb ex ) and Plutonium-239+240 ( 239+240 Pu) as soil erosion tracers for three different grassland management types at the steep slopes (slope angles between 35 and 38°) located in the Central Swiss Alps. All three FRNs identified pastures as having the highest mean (± standard deviation) net soil loss of −6.7 ± 1.1, −9.8 ± 6.8 and −7.0 ± 5.2 Mg ha -1 yr -1 for 137 Cs, 210 Pb ex and 239+240 Pu, respectively. A mean soil loss of −5.7 ± 1.5, −5.2 ± 1.5 and-5.6 ± 2.1 was assessed for hayfields and the lowest rates were established for pastures with dwarf-shrubs (−5.2 ± 2.5, −4.5 ± 2.5 and −3.3 ± 2.4 Mg ha -1 yr -1 for 137 Cs, 210 Pb ex and 239+240 Pu, respectively). These rates, evaluated at sites with an elevated soil erosion risk exceed the respective soil production rates. Among the three FRN methods used, 239+240 Pu appears as the most promising tracer in terms of measurement uncertainty and reduced small scale variability (CV of 13%). Despite a higher level of uncertainty, 210 Pb ex produced comparable results, with a wide range of erosion rates sensitive to changes in grassland management. 210 Pb ex can then be as well considered as a suitable soil tracer to investigate alpine agroecosystems.

  • Excess Lead-210 and Plutonium-239+240: Two suitable radiogenic soil erosion tracers for mountain grassland sites
    Environmental research, 2017
    Co-Authors: Katrin Meusburger, Paolo Porto, Lionel Mabit, C La Spada, Laura Arata, Christine Alewell
    Abstract:

    Abstract The expected growing population and challenges associated with globalisation will increase local food and feed demands and enhance the pressure on local and regional upland soil resources. In light of these potential future developments it is necessary to define sustainable land use and tolerable soil loss rates with methods applicable and adapted to mountainous areas. Fallout-radionuclides (FRNs) are proven techniques to increase our knowledge about the status and resilience of agro-ecosystems. However, the use of the Caesium-137 ( 137 Cs) method is complicated in the European Alps due to its heterogeneous input and the timing of the Chernobyl fallout, which occurred during a few single rain events on partly snow covered ground. Other radioisotopic techniques have been proposed to overcome these limitations. The objective of this study is to evaluate the suitability of excess Lead-210 ( 210 Pb ex ) and Plutonium-239+240 ( 239+240 Pu) as soil erosion tracers for three different grassland management types at the steep slopes (slope angles between 35 and 38°) located in the Central Swiss Alps. All three FRNs identified pastures as having the highest mean (± standard deviation) net soil loss of −6.7 ± 1.1, −9.8 ± 6.8 and −7.0 ± 5.2 Mg ha -1 yr -1 for 137 Cs, 210 Pb ex and 239+240 Pu, respectively. A mean soil loss of −5.7 ± 1.5, −5.2 ± 1.5 and-5.6 ± 2.1 was assessed for hayfields and the lowest rates were established for pastures with dwarf-shrubs (−5.2 ± 2.5, −4.5 ± 2.5 and −3.3 ± 2.4 Mg ha -1 yr -1 for 137 Cs, 210 Pb ex and 239+240 Pu, respectively). These rates, evaluated at sites with an elevated soil erosion risk exceed the respective soil production rates. Among the three FRN methods used, 239+240 Pu appears as the most promising tracer in terms of measurement uncertainty and reduced small scale variability (CV of 13%). Despite a higher level of uncertainty, 210 Pb ex produced comparable results, with a wide range of erosion rates sensitive to changes in grassland management. 210 Pb ex can then be as well considered as a suitable soil tracer to investigate alpine agroecosystems.

  • Baseline Caesium-137 and Plutonium-239+240 inventory assessment for Central Europe
    2017
    Co-Authors: Katrin Meusburger, Lionel Mabit, Christine Alewell, Pasquale Borrelli, O. Evrard, Michael Ketterer, Kristof Van Oost, Panos Panagos
    Abstract:

    Artificial fallout radionuclides (FRNs) such as Caesium-137 and Plutonium-239+240 released as products of the thermonuclear weapons testing that took place from the mid-1950s to the early 1980s and from nuclear power plant accidents (e.g. Chernobyl) are useful tools to quantify soil redistribution. In combination with geostatistics, FRNs may have the potential to bridge the gap between small scale process oriented studies and modelling that simplifies processes and effects over large spatial scales. An essential requirement for the application of FRNs as soil erosion tracers is the establishment of the baseline fallout at undisturbed sites before its comparison to those inventories found at sites undergoing erosion/accumulation. For this purpose, undisturbed topsoil (0-20cm) samples collected in 2009 within the framework of the Land Use/Cover Area frame Survey (LUCAS) have been measured by gamma-spectrometry and ICP-MS to determine 137Cs (n=145) and 239+240Pu (n=108) activities. To restrict the analysis to undisturbed reference sites a geospatial database query selecting only sites having a slope angle

Katrin Meusburger - One of the best experts on this subject based on the ideXlab platform.

  • excess lead 210 and Plutonium 239 240 two suitable radiogenic soil erosion tracers for mountain grassland sites
    Environmental Research, 2018
    Co-Authors: Katrin Meusburger, Paolo Porto, Lionel Mabit, C La Spada, Laura Arata, Christine Alewell
    Abstract:

    Abstract The expected growing population and challenges associated with globalisation will increase local food and feed demands and enhance the pressure on local and regional upland soil resources. In light of these potential future developments it is necessary to define sustainable land use and tolerable soil loss rates with methods applicable and adapted to mountainous areas. Fallout-radionuclides (FRNs) are proven techniques to increase our knowledge about the status and resilience of agro-ecosystems. However, the use of the Caesium-137 ( 137 Cs) method is complicated in the European Alps due to its heterogeneous input and the timing of the Chernobyl fallout, which occurred during a few single rain events on partly snow covered ground. Other radioisotopic techniques have been proposed to overcome these limitations. The objective of this study is to evaluate the suitability of excess Lead-210 ( 210 Pb ex ) and Plutonium-239+240 ( 239+240 Pu) as soil erosion tracers for three different grassland management types at the steep slopes (slope angles between 35 and 38°) located in the Central Swiss Alps. All three FRNs identified pastures as having the highest mean (± standard deviation) net soil loss of −6.7 ± 1.1, −9.8 ± 6.8 and −7.0 ± 5.2 Mg ha -1 yr -1 for 137 Cs, 210 Pb ex and 239+240 Pu, respectively. A mean soil loss of −5.7 ± 1.5, −5.2 ± 1.5 and-5.6 ± 2.1 was assessed for hayfields and the lowest rates were established for pastures with dwarf-shrubs (−5.2 ± 2.5, −4.5 ± 2.5 and −3.3 ± 2.4 Mg ha -1 yr -1 for 137 Cs, 210 Pb ex and 239+240 Pu, respectively). These rates, evaluated at sites with an elevated soil erosion risk exceed the respective soil production rates. Among the three FRN methods used, 239+240 Pu appears as the most promising tracer in terms of measurement uncertainty and reduced small scale variability (CV of 13%). Despite a higher level of uncertainty, 210 Pb ex produced comparable results, with a wide range of erosion rates sensitive to changes in grassland management. 210 Pb ex can then be as well considered as a suitable soil tracer to investigate alpine agroecosystems.

  • Excess Lead-210 and Plutonium-239+240: Two suitable radiogenic soil erosion tracers for mountain grassland sites
    Environmental research, 2017
    Co-Authors: Katrin Meusburger, Paolo Porto, Lionel Mabit, C La Spada, Laura Arata, Christine Alewell
    Abstract:

    Abstract The expected growing population and challenges associated with globalisation will increase local food and feed demands and enhance the pressure on local and regional upland soil resources. In light of these potential future developments it is necessary to define sustainable land use and tolerable soil loss rates with methods applicable and adapted to mountainous areas. Fallout-radionuclides (FRNs) are proven techniques to increase our knowledge about the status and resilience of agro-ecosystems. However, the use of the Caesium-137 ( 137 Cs) method is complicated in the European Alps due to its heterogeneous input and the timing of the Chernobyl fallout, which occurred during a few single rain events on partly snow covered ground. Other radioisotopic techniques have been proposed to overcome these limitations. The objective of this study is to evaluate the suitability of excess Lead-210 ( 210 Pb ex ) and Plutonium-239+240 ( 239+240 Pu) as soil erosion tracers for three different grassland management types at the steep slopes (slope angles between 35 and 38°) located in the Central Swiss Alps. All three FRNs identified pastures as having the highest mean (± standard deviation) net soil loss of −6.7 ± 1.1, −9.8 ± 6.8 and −7.0 ± 5.2 Mg ha -1 yr -1 for 137 Cs, 210 Pb ex and 239+240 Pu, respectively. A mean soil loss of −5.7 ± 1.5, −5.2 ± 1.5 and-5.6 ± 2.1 was assessed for hayfields and the lowest rates were established for pastures with dwarf-shrubs (−5.2 ± 2.5, −4.5 ± 2.5 and −3.3 ± 2.4 Mg ha -1 yr -1 for 137 Cs, 210 Pb ex and 239+240 Pu, respectively). These rates, evaluated at sites with an elevated soil erosion risk exceed the respective soil production rates. Among the three FRN methods used, 239+240 Pu appears as the most promising tracer in terms of measurement uncertainty and reduced small scale variability (CV of 13%). Despite a higher level of uncertainty, 210 Pb ex produced comparable results, with a wide range of erosion rates sensitive to changes in grassland management. 210 Pb ex can then be as well considered as a suitable soil tracer to investigate alpine agroecosystems.

  • Baseline Caesium-137 and Plutonium-239+240 inventory assessment for Central Europe
    2017
    Co-Authors: Katrin Meusburger, Lionel Mabit, Christine Alewell, Pasquale Borrelli, O. Evrard, Michael Ketterer, Kristof Van Oost, Panos Panagos
    Abstract:

    Artificial fallout radionuclides (FRNs) such as Caesium-137 and Plutonium-239+240 released as products of the thermonuclear weapons testing that took place from the mid-1950s to the early 1980s and from nuclear power plant accidents (e.g. Chernobyl) are useful tools to quantify soil redistribution. In combination with geostatistics, FRNs may have the potential to bridge the gap between small scale process oriented studies and modelling that simplifies processes and effects over large spatial scales. An essential requirement for the application of FRNs as soil erosion tracers is the establishment of the baseline fallout at undisturbed sites before its comparison to those inventories found at sites undergoing erosion/accumulation. For this purpose, undisturbed topsoil (0-20cm) samples collected in 2009 within the framework of the Land Use/Cover Area frame Survey (LUCAS) have been measured by gamma-spectrometry and ICP-MS to determine 137Cs (n=145) and 239+240Pu (n=108) activities. To restrict the analysis to undisturbed reference sites a geospatial database query selecting only sites having a slope angle

E.f. Young - One of the best experts on this subject based on the ideXlab platform.

  • transport of Plutonium 239 240pu and caesium 137cs in the irish sea comparison between observations and results from sediment and contaminant transport modelling
    Continental Shelf Research, 2003
    Co-Authors: J.n. Aldridge, Peter J. Kershaw, Juan Brown, David Mccubbin, Kinson S. Leonard, E.f. Young
    Abstract:

    Abstract A model for radionuclide transport in the marine environment is described and applied, in the Irish Sea, to the movement of caesium (137Cs) and Plutonium (239/240Pu) discharged from Sellafield. The model resolves processes operating on tidal time scales, whilst being simple enough to run over decadal time periods. Modelled processes include transport in the water column, exchange of contaminants between dissolved and particulate phases, wave–current sediment resuspension, sediment transport and mixing of material within the seabed. Transport in the water column is by a combination of tide, wind and density-driven flows. Sediment transport is based on the erosion, advection and deposition of three sediment classes representing sand, flocculated mud/silt and fine background components. Transfer of radionuclides between the dissolved and sediment phases is implemented using rate equations. A layered seabed is incorporated with transfers between layers representing biological and physical mixing processes. We demonstrate that the model is able to reproduce observed concentrations of 137Cs and 239/240Pu in the water column, the build-up of 239/240Pu in the seabed over a 30-year time span, including recent changes in seabed inventory distributions. The model is used to identify and quantify the mechanisms responsible for this recent redistribution of 239/240Pu in the region. The results suggest that whilst sediment transport plays a role in redistributing contaminated sediment in the eastern Irish Sea, desorption, followed by transport in the dissolved phase and reabsorption onto particulate material, is the primary mechanism for redistribution of 239/240Pu.

  • Transport of Plutonium (239/240Pu) and caesium (137Cs) in the Irish Sea: comparison between observations and results from sediment and contaminant transport modelling
    Continental Shelf Research, 2003
    Co-Authors: J.n. Aldridge, Peter J. Kershaw, Juan Brown, David Mccubbin, Kinson S. Leonard, E.f. Young
    Abstract:

    Abstract A model for radionuclide transport in the marine environment is described and applied, in the Irish Sea, to the movement of caesium (137Cs) and Plutonium (239/240Pu) discharged from Sellafield. The model resolves processes operating on tidal time scales, whilst being simple enough to run over decadal time periods. Modelled processes include transport in the water column, exchange of contaminants between dissolved and particulate phases, wave–current sediment resuspension, sediment transport and mixing of material within the seabed. Transport in the water column is by a combination of tide, wind and density-driven flows. Sediment transport is based on the erosion, advection and deposition of three sediment classes representing sand, flocculated mud/silt and fine background components. Transfer of radionuclides between the dissolved and sediment phases is implemented using rate equations. A layered seabed is incorporated with transfers between layers representing biological and physical mixing processes. We demonstrate that the model is able to reproduce observed concentrations of 137Cs and 239/240Pu in the water column, the build-up of 239/240Pu in the seabed over a 30-year time span, including recent changes in seabed inventory distributions. The model is used to identify and quantify the mechanisms responsible for this recent redistribution of 239/240Pu in the region. The results suggest that whilst sediment transport plays a role in redistributing contaminated sediment in the eastern Irish Sea, desorption, followed by transport in the dissolved phase and reabsorption onto particulate material, is the primary mechanism for redistribution of 239/240Pu.

Philipp C Molzer - One of the best experts on this subject based on the ideXlab platform.

  • Plutonium 239 240 and americium 241 in soils east of rocky flats colorado
    Journal of Environmental Quality, 1994
    Co-Authors: Iggy M Litaor, M L Thompson, G R Barth, Philipp C Molzer
    Abstract:

    Soils east of the Rocky Flats (RF) near Golden, CO, were contaminated with Pu-239 + 240 and Am-241 as a result of past waste-storage practices. The physiocochemical parameters that govern the actinides distribution in the soil are poorly understood. Twenty-six soil pits at various distances and directions from a contaminated site at RF were excavated, sampled, and analyzed for actinide activities as well as selected physical, chemical, and mineralogical attributes. Plutonium-239+240 and Am-241 activities in the soils ranged form 164 280 Bq/kg to 0.0037 Bq/kg, decreasing with distance from the source. More than 90% of the Pu-239 + 240 and Am-241 activities were confined to the upper 12 cm of the soil, regardless of the soil characteristics, or distance and direction from the source. Evidence of preferential transport in macropores formed along decayed root channels was observed in four soil pits and had translocated Pu-239 + 240 to a depth of 90 cm. This transport mechanism increased by a factor of 30 the level of Pu-239 + 240 activity at this depth. Earthworm activity is probably important in the redistribution of actinides in the upper 40 cm of many of the soils investigated. Planning of future remedial activities at RFmore » should consider the findings of this contaminant-transport study. 34 refs., 5 figs., 2 tabs.« less

  • Plutonium-239 + 240 and Americium-241 in soils east of Rocky Flats, Colorado
    Journal of Environmental Quality, 1994
    Co-Authors: M. Iggy Litaor, M L Thompson, G R Barth, Philipp C Molzer
    Abstract:

    Soils east of the Rocky Flats (RF) near Golden, CO, were contaminated with Pu-239 + 240 and Am-241 as a result of past waste-storage practices. The physiocochemical parameters that govern the actinides distribution in the soil are poorly understood. Twenty-six soil pits at various distances and directions from a contaminated site at RF were excavated, sampled, and analyzed for actinide activities as well as selected physical, chemical, and mineralogical attributes. Plutonium-239+240 and Am-241 activities in the soils ranged form 164 280 Bq/kg to 0.0037 Bq/kg, decreasing with distance from the source. More than 90% of the Pu-239 + 240 and Am-241 activities were confined to the upper 12 cm of the soil, regardless of the soil characteristics, or distance and direction from the source. Evidence of preferential transport in macropores formed along decayed root channels was observed in four soil pits and had translocated Pu-239 + 240 to a depth of 90 cm. This transport mechanism increased by a factor of 30 the level of Pu-239 + 240 activity at this depth. Earthworm activity is probably important in the redistribution of actinides in the upper 40 cm of many of the soils investigated. Planning of future remedial activities at RFmore » should consider the findings of this contaminant-transport study. 34 refs., 5 figs., 2 tabs.« less

Lionel Mabit - One of the best experts on this subject based on the ideXlab platform.

  • excess lead 210 and Plutonium 239 240 two suitable radiogenic soil erosion tracers for mountain grassland sites
    Environmental Research, 2018
    Co-Authors: Katrin Meusburger, Paolo Porto, Lionel Mabit, C La Spada, Laura Arata, Christine Alewell
    Abstract:

    Abstract The expected growing population and challenges associated with globalisation will increase local food and feed demands and enhance the pressure on local and regional upland soil resources. In light of these potential future developments it is necessary to define sustainable land use and tolerable soil loss rates with methods applicable and adapted to mountainous areas. Fallout-radionuclides (FRNs) are proven techniques to increase our knowledge about the status and resilience of agro-ecosystems. However, the use of the Caesium-137 ( 137 Cs) method is complicated in the European Alps due to its heterogeneous input and the timing of the Chernobyl fallout, which occurred during a few single rain events on partly snow covered ground. Other radioisotopic techniques have been proposed to overcome these limitations. The objective of this study is to evaluate the suitability of excess Lead-210 ( 210 Pb ex ) and Plutonium-239+240 ( 239+240 Pu) as soil erosion tracers for three different grassland management types at the steep slopes (slope angles between 35 and 38°) located in the Central Swiss Alps. All three FRNs identified pastures as having the highest mean (± standard deviation) net soil loss of −6.7 ± 1.1, −9.8 ± 6.8 and −7.0 ± 5.2 Mg ha -1 yr -1 for 137 Cs, 210 Pb ex and 239+240 Pu, respectively. A mean soil loss of −5.7 ± 1.5, −5.2 ± 1.5 and-5.6 ± 2.1 was assessed for hayfields and the lowest rates were established for pastures with dwarf-shrubs (−5.2 ± 2.5, −4.5 ± 2.5 and −3.3 ± 2.4 Mg ha -1 yr -1 for 137 Cs, 210 Pb ex and 239+240 Pu, respectively). These rates, evaluated at sites with an elevated soil erosion risk exceed the respective soil production rates. Among the three FRN methods used, 239+240 Pu appears as the most promising tracer in terms of measurement uncertainty and reduced small scale variability (CV of 13%). Despite a higher level of uncertainty, 210 Pb ex produced comparable results, with a wide range of erosion rates sensitive to changes in grassland management. 210 Pb ex can then be as well considered as a suitable soil tracer to investigate alpine agroecosystems.

  • Excess Lead-210 and Plutonium-239+240: Two suitable radiogenic soil erosion tracers for mountain grassland sites
    Environmental research, 2017
    Co-Authors: Katrin Meusburger, Paolo Porto, Lionel Mabit, C La Spada, Laura Arata, Christine Alewell
    Abstract:

    Abstract The expected growing population and challenges associated with globalisation will increase local food and feed demands and enhance the pressure on local and regional upland soil resources. In light of these potential future developments it is necessary to define sustainable land use and tolerable soil loss rates with methods applicable and adapted to mountainous areas. Fallout-radionuclides (FRNs) are proven techniques to increase our knowledge about the status and resilience of agro-ecosystems. However, the use of the Caesium-137 ( 137 Cs) method is complicated in the European Alps due to its heterogeneous input and the timing of the Chernobyl fallout, which occurred during a few single rain events on partly snow covered ground. Other radioisotopic techniques have been proposed to overcome these limitations. The objective of this study is to evaluate the suitability of excess Lead-210 ( 210 Pb ex ) and Plutonium-239+240 ( 239+240 Pu) as soil erosion tracers for three different grassland management types at the steep slopes (slope angles between 35 and 38°) located in the Central Swiss Alps. All three FRNs identified pastures as having the highest mean (± standard deviation) net soil loss of −6.7 ± 1.1, −9.8 ± 6.8 and −7.0 ± 5.2 Mg ha -1 yr -1 for 137 Cs, 210 Pb ex and 239+240 Pu, respectively. A mean soil loss of −5.7 ± 1.5, −5.2 ± 1.5 and-5.6 ± 2.1 was assessed for hayfields and the lowest rates were established for pastures with dwarf-shrubs (−5.2 ± 2.5, −4.5 ± 2.5 and −3.3 ± 2.4 Mg ha -1 yr -1 for 137 Cs, 210 Pb ex and 239+240 Pu, respectively). These rates, evaluated at sites with an elevated soil erosion risk exceed the respective soil production rates. Among the three FRN methods used, 239+240 Pu appears as the most promising tracer in terms of measurement uncertainty and reduced small scale variability (CV of 13%). Despite a higher level of uncertainty, 210 Pb ex produced comparable results, with a wide range of erosion rates sensitive to changes in grassland management. 210 Pb ex can then be as well considered as a suitable soil tracer to investigate alpine agroecosystems.

  • Baseline Caesium-137 and Plutonium-239+240 inventory assessment for Central Europe
    2017
    Co-Authors: Katrin Meusburger, Lionel Mabit, Christine Alewell, Pasquale Borrelli, O. Evrard, Michael Ketterer, Kristof Van Oost, Panos Panagos
    Abstract:

    Artificial fallout radionuclides (FRNs) such as Caesium-137 and Plutonium-239+240 released as products of the thermonuclear weapons testing that took place from the mid-1950s to the early 1980s and from nuclear power plant accidents (e.g. Chernobyl) are useful tools to quantify soil redistribution. In combination with geostatistics, FRNs may have the potential to bridge the gap between small scale process oriented studies and modelling that simplifies processes and effects over large spatial scales. An essential requirement for the application of FRNs as soil erosion tracers is the establishment of the baseline fallout at undisturbed sites before its comparison to those inventories found at sites undergoing erosion/accumulation. For this purpose, undisturbed topsoil (0-20cm) samples collected in 2009 within the framework of the Land Use/Cover Area frame Survey (LUCAS) have been measured by gamma-spectrometry and ICP-MS to determine 137Cs (n=145) and 239+240Pu (n=108) activities. To restrict the analysis to undisturbed reference sites a geospatial database query selecting only sites having a slope angle