Wind Erosion in Western Queensland Australia

Chapter 2 – Land Erodibility ControlsErodibility • Susceptibility of a soil to detachment and transportation by anerosive agent.• A composite expression of soil properties that affect the mechanical,chemical and physical properties of a soil. Is independent oftopography, land use, rainfall intensity and plant cover, but may bechanged by management.Erosion Hazard • Susceptibility of a parcel of land to erosion.• Dependent on a combination of climate, landform, soil, land use andmanagement factors.Erosion Risk • Intrinsic susceptibility of a parcel of land to erosion.• Dependent on climate, landforms and soil factors, but independent ofland management.Erodibility and erosion hazard/risk work opposite to “erosivity”. Erosivity is the potential orcapacity of the wind to mobilize particles on the soil surface (Lal and Elliot, 1994).Susceptibility rankings are based on the premise that a location having a high erodibility ismore susceptible to erosion than a location with low erodibility, and that a highly erosivewind has more energy than a wind with low erosivity. Conceptually, erodibility isindependent of wind erosivity. However, if erodibility is to be measured to develop a rankingsystem, wind erosivity must be considered. This necessity is reflected in even the earlieststudies of wind erodibility. These studies applied wind tunnel experimentation and fieldmonitoring to determine the susceptibility of soils to wind erosion in cultivated fields.Chepil (1953) used constant wind erosivity conditions to determine soil and wind tunnelerodibility factors for the Wind Erosion Equation (WEQ). More recent studies have definederodibility rankings under a range of wind erosivities. Studies in the late 1950s to 1960sprovided a range of approaches for developing erodibility factors (e.g. Chepil and Woodruff,1963; Woodruff and Siddoway, 1965). The factors can be characterised by differences in thespatial scales at which they were derived (Table 2.1).26