Wind Erosion in Western Queensland Australia

Chapter 3 – Modelling Land Erodibility Reviewregional scale models. For the purposes of this discussion, regional scale modelling isconsidered to be that where models are applied to areas ~10 4 km 2 , and operating overnumerous landscapes within a region or continent. The final group are the continental toglobal scale models. These models operate at scales >10 4 km 2 , and are applied to simulateglobal scale dust dynamics.3.2 Field Scale Wind Erosion ModelsThis section presents a review of field scale wind erosion models. The models reviewedinclude the Wind Erosion Equation (WEQ), Revised Wind Erosion Equation (RWEQ), WindErosion Stochastic Simulator (WESS), Wind Erosion Prediction System (WEPS), and TexasErosion Analysis Model (TEAM). These models represent a range of approaches forassessing wind erosion from farm fields at different spatial and temporal resolutions. The wayin which land erodibility is quantified in each model is seen as a progression from earlyempirical research with limited computing capability, to more recent process-based studies.3.2.1 Wind Erosion Equation (WEQ)The Wind Erosion Equation (WEQ) was developed by Woodruff and Siddoway (1965) topredict annual soil erosion (kgha -1 ) from farm fields in the United States. WEQ was designedfor both the analysis and management of wind erosion, with a central aim in its developmentbeing to apply the model to determine the effects of field conditions and erosion mitigationstrategies on erosion rates.WEQ was developed from empirical relationships defining the effects of important winderosion controls on soil loss rates. The foundation of WEQ is its soil erodibility factor. Theempirical functions constituting the model were derived from field and wind tunnelexperiments under a range of soil types and roughness conditions (e.g. Chepil and Woodruff,1954). WEQ uses a relationship between five generalised factors that account for the majorcontrols on wind erosion in cultivated environments. These factors are combined into fiveinputs for the model in the form:( I ', C',K',L'V )E = f,(3.1)71