Abstract
Convective flow within bed sediment is an important mechanism enhancing the mobility of chemicals, both natural and anthropogenic, and thermal energy in this region of aquatic environments1,2. Experimental observations indicated that significant in-bed convection currents can be generated by water flowing over small obstructions on the surface of a porous bed. Significant porewater flow is induced by imbalances in pressure over distance, generated by differences in temperature, density and hydrostatic head3. We demonstrate here by laboratory simulation and a vignette model that flow over bedforms induces additional pressure imbalances which generate significant and complex convection currents within porous bed sediment. A model is proposed for estimating Peclet numbers for this effect/The results have particular application to chemical transport in the upper sediment layer that is often the recipient of high levels of chemical contamination. Although our analysis reflects river conditions, the results may have wider applications and include submarine currents moving over dune-like mega ripples on the ocean floor.
This is a preview of subscription content, access via your institution
Access options
Subscribe to this journal
Receive 51 print issues and online access
$199.00 per year
only $3.90 per issue
Buy this article
- Purchase on Springer Link
- Instant access to full article PDF
Prices may be subject to local taxes which are calculated during checkout
Similar content being viewed by others
References
Lerman, A. Chemical Processes—Water and Sediment Environments, 65 (Wiiey, New York, 1979).
Berner, R. A. Early Diagenesis, 117 (Princeton University Press, 1980).
Bird, R. E., Stewart, W. E. & Lightfoot, E. N. Transport Phenomena, 580 (Wiley, New York, 1960).
Simon, D. B., Richardson, E. V. & Nordin, C. F. Jr Am. Ass. petrol. Geol. Spec. Publ. No. 12, 34–51 (Year?).
Schlichting, H. Boundary Layer Theory, 425–427, 7th edn (McGraw-Hill, New York, 1979).
Vittal, N., Ranga Raju, K. G. & Garde, R. J. J. Hydraul. Res. 15, 19 (1977).
Case, R. J. & Koulermos, A. Flow Through Gravel in River Beds (Experimental Project Report Department Chemical Engineering, Univ. Exeter, 1983).
Mitwally, H. Nile River Sediment Porosity and Permeability Measurements (Soil Mechanics Laboratory Report, Alexandria Univ. 1985).
Hurst, H. E. & Phillips, P. The Nile Basin, 43–51, Vol. 4 (Government Press, Cairo, 1931).
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Thibodeaux, L., Boyle, J. Bedform-generated convective transport in bottom sediment. Nature 325, 341–343 (1987). https://doi.org/10.1038/325341a0
Received:
Accepted:
Issue Date:
DOI: https://doi.org/10.1038/325341a0
This article is cited by
-
Effects of groundwater inputs on algal assemblages and cellulose decomposition differ based on habitat type in an agricultural stream
Hydrobiologia (2023)
-
Direct numerical simulation of the scouring of a brittle streambed in a turbulent channel flow
Acta Mechanica (2021)
-
Channel width, bedform length and turbulence: numerical investigation of flow dynamics over laboratory-scale pool–riffle sequences
Environmental Fluid Mechanics (2020)
-
Spatial distribution of spawning redds and larvae of Rhinogobius flumineus in relation to hydrogeomorphological characteristics in Kamo River, Japan
Paddy and Water Environment (2019)
-
A conceptual framework for the identification and characterization of lacustrine spawning habitats for native lake charr Salvelinus namaycush
Environmental Biology of Fishes (2019)
Comments
By submitting a comment you agree to abide by our Terms and Community Guidelines. If you find something abusive or that does not comply with our terms or guidelines please flag it as inappropriate.
