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Title: Modeling and interpreting element ratios in water and sediments: A sensitivity analysis of post-Chernobyl Ru:Cs ratios

Abstract

When elements are simultaneously added to lakes, experimentally or by accident, their ratios in the water phase and in bottom sediments can change with time due to differential partitioning between solution and suspended particles or sediments. A number of equations are developed to show the change of ratio with time in water and sediments assuming simultaneous pulse inputs followed by a range of combinations of loss processes form solution (i.e. hydraulic losses, sorption to particles followed by settling, and diffusion into the sediments). The pattern of events is discussed both for pulse events with specific limiting assumptions and for combined continuous and pulse inputs. The models show that elemental ratios in sediments are generally less sensitive indicators of differential partitioning that are elemental ratios in water. For lakes with long residence times, the long-term elemental ratio in the sediments does not differ from that in the initial spike to the water column, but for short residence times, it is directly dependent on the ratio of either partition or diffusion coefficients. The models are used to interpret Ru:Cs ratios measured in the water and sediments of Esthwaite Water subsequent to the pulse input of Chernobyl fallout. The ratios can be explainedmore » by assuming nuclides were lost either by flusing and sorption or by flushing, sorption, and diffusion. The process combination of flushing and diffusion in incompatible with the observed constant ratios. 12 refs., 2 figs., 4 tabs.« less

Authors:
;  [1]; ; ;  [2];  [3];  [4]
  1. Institute of Freshwater Ecology, Windermere Lab., Cumbria (United Kingdom)
  2. Univ. of Lancaster (United Kingdom)
  3. Univ. of Manchester (United Kingdom)
  4. Institute of Terrestrial Ecology, Merlewood Lab., Cumbria (United Kingdom)
Publication Date:
Sponsoring Org.:
USDOE
OSTI Identifier:
387344
Resource Type:
Journal Article
Resource Relation:
Journal Name: Limnology and Oceanography; Journal Volume: 40; Journal Issue: 7; Other Information: PBD: Nov 1995
Country of Publication:
United States
Language:
English
Subject:
54 ENVIRONMENTAL SCIENCES; 57 HEALTH AND SAFETY; LAKES; CONTAMINATION; SEDIMENTS; ISOTOPE RATIO; SENSITIVITY ANALYSIS; CESIUM; RUTHENIUM; REACTOR ACCIDENTS; ENVIRONMENTAL EFFECTS; CHERNOBYLSK-4 REACTOR

Citation Formats

Hilton, J., Rigg, E., Davison, W., Hamilton-Taylor, J., Kelly, M., Livens, F.R., and Singleton, D.L. Modeling and interpreting element ratios in water and sediments: A sensitivity analysis of post-Chernobyl Ru:Cs ratios. United States: N. p., 1995. Web. doi:10.4319/lo.1995.40.7.1302.
Hilton, J., Rigg, E., Davison, W., Hamilton-Taylor, J., Kelly, M., Livens, F.R., & Singleton, D.L. Modeling and interpreting element ratios in water and sediments: A sensitivity analysis of post-Chernobyl Ru:Cs ratios. United States. doi:10.4319/lo.1995.40.7.1302.
Hilton, J., Rigg, E., Davison, W., Hamilton-Taylor, J., Kelly, M., Livens, F.R., and Singleton, D.L. 1995. "Modeling and interpreting element ratios in water and sediments: A sensitivity analysis of post-Chernobyl Ru:Cs ratios". United States. doi:10.4319/lo.1995.40.7.1302.
@article{osti_387344,
title = {Modeling and interpreting element ratios in water and sediments: A sensitivity analysis of post-Chernobyl Ru:Cs ratios},
author = {Hilton, J. and Rigg, E. and Davison, W. and Hamilton-Taylor, J. and Kelly, M. and Livens, F.R. and Singleton, D.L.},
abstractNote = {When elements are simultaneously added to lakes, experimentally or by accident, their ratios in the water phase and in bottom sediments can change with time due to differential partitioning between solution and suspended particles or sediments. A number of equations are developed to show the change of ratio with time in water and sediments assuming simultaneous pulse inputs followed by a range of combinations of loss processes form solution (i.e. hydraulic losses, sorption to particles followed by settling, and diffusion into the sediments). The pattern of events is discussed both for pulse events with specific limiting assumptions and for combined continuous and pulse inputs. The models show that elemental ratios in sediments are generally less sensitive indicators of differential partitioning that are elemental ratios in water. For lakes with long residence times, the long-term elemental ratio in the sediments does not differ from that in the initial spike to the water column, but for short residence times, it is directly dependent on the ratio of either partition or diffusion coefficients. The models are used to interpret Ru:Cs ratios measured in the water and sediments of Esthwaite Water subsequent to the pulse input of Chernobyl fallout. The ratios can be explained by assuming nuclides were lost either by flusing and sorption or by flushing, sorption, and diffusion. The process combination of flushing and diffusion in incompatible with the observed constant ratios. 12 refs., 2 figs., 4 tabs.},
doi = {10.4319/lo.1995.40.7.1302},
journal = {Limnology and Oceanography},
number = 7,
volume = 40,
place = {United States},
year = 1995,
month =
}
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