@conference {JRN54631, title = {A spatial dynamic framework for landscape-scale assessment of accelerated wind erosion in Australian rangelands}, booktitle = {9th International Conference on Aeolian Research}, year = {2016}, month = {07/2016}, publisher = {International Conference on Aeolian Research}, organization = {International Conference on Aeolian Research}, address = {Mildura, Australia}, abstract = {
An estimated 110 Mt of dust is eroded by wind from the Australian land surface each year, most of which originates from the arid and semi-arid areas. Livestock production is a major activity in these areas and can increase their susceptibility to wind erosion by further reducing vegetation cover and modifying surface soil stability. While accelerated wind erosion is widely accepted to exist, the scale of grazing impacts in rangelands is still largely debated, because pastoral land management activities have received less research attention than cultivated land management. To date, most methods used to assess the impacts of pastoral activities on wind erosion have been made limited progress in discriminating accelerated wind erosion, due to: 1) their broad spatial and/or temporal resolutions and 2) the scarcity of data on the effects of spatial and temporal variations of land management impacts on land erodibility. In addition, the outcomes of these broad scale studies have seldom been translated into recommendations that are relevant for land managers. \ Here, we present a framework developed to assess accelerated wind erosion at landscape scale. The framework combines soil erodibility, vegetation and grazing intensity data in a Geographical Information System to quantify land erodibility and accelerated erosion risk on different land types. Land erodibility is defined using process-based relationships, integrating vegetation cover and erodible soil fraction. Grazing intensity is determined by the distance from the livestock watering points. For every time period, the land erodibility of a landscape is compared to a reference time period, when erodibility was primarily influenced by climate conditions. Accelerated wind erosion risk maps are produced for each land type. \ We apply the framework to multiple land types in rangelands of western Queensland in Australia. Our results show that the risk of accelerated erosion is much greater during drier periods than in wetter periods. Up to 84\% of the landscape evidenced accelerated erosion in dryer periods, whereas in wetter periods less than 10\% of the landscape displayed some level of accelerated erosion. Overall, the grazing gradient-wind erosion framework produces encouraging results; overcoming three limitations of previous methods for assessing accelerated erosion, by: 1) accounting for spatio-temporal variations of land management, 2) integrating a soil erodibility component which includes the effect of trampling, and 3) operating at a landscape scale to increase its functionality for land managers.
}, author = {Aubault, Helene and Nicholas Webb and Craig Strong and Grant McTainish} } @conference {JRN54635, title = {A spatial dynamic framework for landscape-scale assessment of accelerated wind erosion in Australian rangelands}, booktitle = {9th International Conference on Aeolian Research}, year = {2016}, month = {07/2016}, publisher = {International Conference on Aeolian Research}, organization = {International Conference on Aeolian Research}, address = {Mildura, Australia}, abstract = {
An estimated 110 Mt of dust is eroded by wind from the Australian land surface each year, most of which originates from the arid and semi-arid areas. Livestock production is a major activity in these areas and can increase their susceptibility to wind erosion by further reducing vegetation cover and modifying surface soil stability. While accelerated wind erosion is widely accepted to exist, the scale of grazing impacts in rangelands is still largely debated, because pastoral land management activities have received less research attention than cultivated land management. To date, most methods used to assess the impacts of pastoral activities on wind erosion have been made limited progress in discriminating accelerated wind erosion, due to: 1) their broad spatial and/or temporal resolutions and 2) the scarcity of data on the effects of spatial and temporal variations of land management impacts on land erodibility. In addition, the outcomes of these broad scale studies have seldom been translated into recommendations that are relevant for land managers.\ 
Here, we present a framework developed to assess accelerated wind erosion at landscape scale. The framework combines soil erodibility, vegetation and grazing intensity data in a Geographical Information System to quantify land erodibility and accelerated erosion risk on different land types. Land erodibility is defined using process-based relationships, integrating vegetation cover and erodible soil fraction. Grazing intensity is determined by the distance from the livestock watering points. For every time period, the land erodibility of a landscape is compared to a reference time period, when erodibility was primarily influenced by climate conditions. Accelerated wind erosion risk maps are produced for each land type.\ 
We apply the framework to multiple land types in rangelands of western Queensland in Australia. Our results show that the risk of accelerated erosion is much greater during drier periods than in wetter periods. Up to 84\% of the landscape evidenced accelerated erosion in dryer periods, whereas in wetter periods less than 10\% of the landscape displayed some level of accelerated erosion. Overall, the grazing gradient-wind erosion framework produces encouraging results; overcoming three limitations of previous methods for assessing accelerated erosion, by: 1) accounting for spatio-temporal variations of land management, 2) integrating a soil erodibility component which includes the effect of trampling, and 3) operating at a landscape scale to increase its functionality for land managers.
}, author = {Aubault, Helene and Nicholas Webb and Craig Strong and Grant McTainish} } @article {JRN54160, title = {Grazing impacts on the susceptibility of rangelands to wind erosion: the effects of stocking rate, stocking strategy and land condition}, journal = {Aeolian Research}, volume = {17}, year = {2015}, month = {03/2015}, pages = {89-99}, chapter = {89}, abstract = {

An estimated 110 Mt of dust is eroded by wind from the Australian land surface each year, most of which originates from the arid and semi-arid rangelands. Livestock production is thought to increase the susceptibility of the rangelands to wind erosion by reducing vegetation cover and modifying surface soil stability. However, research is yet to quantify the impacts of grazing land management on the erodibility of the Australian rangelands, or determine how these impacts vary among land types and over time. We present a simulation analysis that links a pasture growth and animal production model (GRASP) to the Australian Land Erodibility Model (AUSLEM) to evaluate the impacts of stocking rate, stocking strategy and land condition on the erodibility of four land types in western Queensland, Australia. Our results show that declining land condition, over stocking, and using inflexible stocking strategies have potential to increase land erodibility and amplify accelerated soil erosion. However, land erodibility responses to grazing are complex and influenced by land type sensitivities to different grazing strategies and local climate characteristics. Our simulations show that land types which are more resilient to livestock grazing tend to be least susceptible to accelerated wind erosion. Increases in land erodibility are found to occur most often during climatic transitions when vegetation cover is most sensitive to grazing pressure. However, grazing effects are limited during extreme wet and dry periods when the influence of climate on vegetation cover is strongest. Our research provides the opportunity to estimate the effects of different land management practices across a range of land types, and provides a better understanding of the mechanisms of accelerated erosion resulting from pastoral activities. The approach could help further assessment of land erodibility at a broader scale notably if combined with wind erosion models.

}, keywords = {aeolian, dust, land degradation, rangeland management, soil erodibility, stocking rates}, doi = {10.1016/j.aeolia.2014.12.005}, url = {/files/bibliography/15-009.pdf}, author = {Aubault, Helene and Nicholas Webb and Craig Strong and Grant McTainish and John Leys and Scanlan, Joe C.} } @proceedings {JRN54540, title = {The impacts of grazing land management on the wind erodibility of the Mulga Lands of western Queensland, Australia}, volume = {p. 60}, year = {2012}, month = {09/2012}, publisher = {Australian Rangeland Society}, address = {Kununurra, Western Australia}, abstract = {An estimated 100 Mt of dust is eroded by wind from the Australian land surface each year. Wind erosion may be widespread across the arid and semi-arid rangelands, with impacts on soil nutrients, carbon and ecosystem services, human health, and climate. The susceptibility of landscapes to wind erosion (their erodibility) is highly sensitive to changes in vegetation cover and soil properties like crusting and aggregation, which control the area of bare ground exposed to erosive winds, and the availability of fine erodible sediment. Pastoralism, including the production of cattle and sheep, is thought to modify these controls through its impacts on vegetation cover and soil surface properties. However, research is yet to quantify the impact of grazing land management on the erodibility of rangelands, or how these impacts vary between land types. We present a simulation analysis that implements the Australian Land Erodibility Model (AUSLEM) in line with a pasture growth and animal production model (GRASP) to evaluate the impacts of grazing management on the erodibility of 5 land types in western Queensland. The study has tested separately the effects of stocking rates, stocking strategies and land condition on wind erodibility. Our results show that wind erodibility increases with stocking rate, showing a nonlinear response that varies in intensity between land types. Susceptibility of the land types to wind erosion is shown to increase under stocking strategies that lack flexibility or the capacity to rapidly destock in response to drought conditions. However, moving from high stocking rates under a fixed stocking to a more flexible strategy is shown to have a greater effect on erodibility than differences between flexible stocking strategies based around the long term safe stocking rates. The degradation of land condition results in an increase of wind erodibility with an abrupt change of rates representing major shifts in environmental conditions. The analysis indicates that historical stocking rates have had a high impact on wind erodibility; however, under the current stocking rate, impacts on wind erodibility are reduced. Wind erodibility can be reduced by adopting a conservative management with low stocking rates as well as maintaining the land in good condition.}, keywords = {GRASP, land degradation, management, modelling, stocking rate, wind erosion}, author = {Aubault, Helene and Nicholas Webb and Scanlan, Joe C. and Craig Strong and John Leys} }