Wind Erosion in Western Queensland Australia

Chapter 8 – Conclusionshave direct relevance to policy and management decision making which are implementedacross these scales in rangeland environments.The research presented in this thesis contributes toward modelling and understandingregional scale wind erosion processes both in Australia, and internationally. In the context ofthe wind erosion models reviewed in Chapter 3, this research has developed a new toolspecifically aimed at assessing land susceptibility to wind erosion at the landscape (10 3 km 2 )to regional (>10 4 km 2 ) scales. This capacity fills a gap in wind erosion modelling betweenthese scales, and a lack of research to assess spatial and temporal variations in land erodibilityin rangeland environments. In terms of model functionality and scale, AUSLEM is nowpositioned between the highly empirical field-scale models like RWEQ, WEPS and TEAM,and the deterministic regional to continental scale DPM and WEAM models (Figure 3.1).The AUSLEM framework differs from other regional scale wind erosion models such asDPM (Marticorena and Bergametti, 1995) and IWEMS (Lu and Shao, 2001) in that itoperates at a higher spatial resolution (5 x 5 km), and using Aussie GRASS inputs could beused to assess land erodibility back to January 1890. As shown in Chapter 7, this applicationpotential provides a powerful tool for examining land erodibility responses to climatevariability and land management factors. AUSLEM suffers a similar limitation to other winderosion models in that it does not account for short-term temporal variations in soilerodibility. Nevertheless, this research has produced a framework (Chapter 4) for modellingdynamic changes in soil erodibility that may be applicable not just to AUSLEM, but throughother wind erosion modelling systems. Pursuing the development of soil erodibility modelsmust be a priority in wind erosion research as few models currently contain such schemes,and those that do have a high dependence on field-measured input data (e.g. Hagen, 1991;Fryrear et al., 1998; Gregory et al., 2004).Application of AUSLEM has demonstrated how land erodibility in western Queensland isdynamic and responsive to climate variability at the landscape to regional scales. Theseresearch outcomes complement the modelling results of Shao and Leslie (1997), Lu (1999)and Lu and Shao (2001), who have shown the importance of land erodibility dynamics inmodelling dust emission processes in Australia. While AUSLEM and IWEMS have differentmodel schemes to account for vegetation, soil moisture and soil textural effects on theerodibility of the land surface (Chapter 3), the underlying conceptual frameworks of the197