Home

About Us

Overview

 

Modelling

Lab Experiments

Photogrammetry

Field Work

Laser Scanning

 

Publications

Modelling rainfall-driven erosion on a 3% slope. Graphs show total concentration, sediment concentrations for individual size classes, and the evolution of the settling velocity distribution respectively.

Modelling

The Hairsine-Rose (H-R) soil erosion model [Hairsine & Rose, 1991, 1992a, b] will be used as the basis for our work. This model considers erosion and deposition processes separately, takes into account the development of a deposited layer, and allows for multiple sediment size classes. This last aspect makes it particularly suitable for pollutant transport modelling since many contaminants adhere strongly to the smaller clay fractions of the soil.

Previous—mostly analytical—work has shown that the model can accurately simulate soil erosion and sediment transport under various conditions. However, the application of the model to more complex scenarios has been restricted due to the limitations of analytical solutions. We propose to develop a numerical scheme to solve the H-R model coupled with the St. Venant equations for overland flow. This would allow us to model a wider range of soil erosion scenarios than was previously possible.

The model will then be extended for pollutant transport modelling. There are two components to the transported pollutant load: the dissolved pollutants in the runoff water and the pollutants attached to particles. Previous research by Walton et al. [2000] and Wallach et al. [2001] only considered the dissolved component. We will modify the theory to account for the sorbed pollutants.

 

References

P. B. Hairsine & C. W. Rose (1991). `Rainfall Detachment and Deposition: Sediment Transport in the Absence of Flow-Driven Processes'. Soil Sci Soc Am J 55(2):320-324.

P. B. Hairsine & C. W. Rose (1992a). `Modeling water erosion due to overland flow using physical principles, 1, Sheet flow'. Water Resources Research 28(1):237-243.

P. B. Hairsine & C. W. Rose (1992b). `Modeling water erosion due to overland flow using physical principles, 2, Rill flow'. Water Resources Research 28(1):245-250.

R. S. Walton, et al. (2000). `Solute transport by surface runoff from low-angle slopes: theory and application'. Hydrological Processes 14(6):1139-1158.

R. Wallach, et al. (2001). `A comprehensive mathematical model for transport of soil-dissolved chemicals by overland flow'. Journal of Hydrology 247(1-2):85-99.

MultiSEM

Mathematical Modelling, Experiments & Field Evaluation

Multi-dimensional Soil Erosion & Associated Chemical Transport