Johnson, MO, Mudd, SM, Pillans, B et al. (4 more authors) (2014) Quantifying the rate and depth dependence of bioturbation based on optically-stimulated luminescence (OSL) dates and meteoric 10Be. Earth Surface Processes and Landforms, 39 (9). 1188 - 1196. ISSN 0197-9337
Abstract
Both the rate and the vertical distribution of soil disturbance modify soil properties such as porosity, particle size, chemical composition and age structure; all of which play an important role in a soil's biogeochemical functioning. Whereas rates of mixing have been previously quantified, the nature of bioturbation's depth dependence remains poorly constrained. Here we constrain, for the first time, the relationship between mixing rate and depth in a bioturbated soil in northeast Queensland, Australia using a novel method combining OSL (optically-stimulated luminescence) ages and meteoric beryllium-10 (10Be) inventories. We find that the best fit mixing rate decreases non-linearly with increasing soil depth in this soil and the characteristic length scale of 0.28m over which the mixing coefficient decays is comparable to reported rooting depth coefficients. In addition we show that estimates of surface mixing rates from OSL data are highly dependent on erosion rate and that erosion rate must be constrained if accurate mixing rates are to be quantified. We calculate surface diffusion-like mixing coefficients of 1.8×10-4 and 2.1×10-4m2yr-1 for the studied soil for two different estimates of soil erosion.
Metadata
Item Type: | Article |
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Authors/Creators: |
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Copyright, Publisher and Additional Information: | © 2014 The Authors. Earth Surface Processes and Landforms Published by John Wiley & Sons Ltd. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited. |
Keywords: | Bioturbation; Erosion; Optically-stimulated luminescence; Soil mixing |
Dates: |
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Institution: | The University of Leeds |
Academic Units: | The University of Leeds > Faculty of Environment (Leeds) > School of Geography (Leeds) |
Depositing User: | Symplectic Publications |
Date Deposited: | 01 Oct 2014 08:10 |
Last Modified: | 19 Jan 2018 15:11 |
Published Version: | http://dx.doi.org/10.1002/esp.3520 |
Status: | Published |
Publisher: | John Wiley and Sons Ltd |
Identification Number: | 10.1002/esp.3520 |
Open Archives Initiative ID (OAI ID): | oai:eprints.whiterose.ac.uk:77919 |