Wind Erosion in Western Queensland Australia

Chapter 4 –Modelling Soil Erodibility Dynamicssoil physical, chemical and biological properties and the density/specific gravity of theaggregates.Figure 4.2 Graphs illustrating the effect of (a) changing the non-erodible fraction of a soil (%DA >0.84 mm) on (b) the position of the curve defining the relationship between soil clay content(percentage clay) and soil erodibility as indicated by the streamwise sediment flux (Q,, represented bycircles) at a wind velocity of 65 kmh -1 (after Leys et al., 1996).Given that changes in soil erodibility can be defined by a shift in position of the curvedefined by Equation (4.2), and the nature of this shift is determined by the %DA-Qrelationship defined by Equation (4.5), the physical dimensions of the soil erodibilitycontinuum can now be described. To start, an expression defining the minimum erodibilitylimit needs to be selected. Here a power function of the form of Equation (4.2) was fitted tothe data presented by Leys et al. (1996) for non-cultivated (crusted) soils. The equation (r 2 =0.78, p < 0.01) is of the form:107