Soil Mapping and Assessment In Arid Lands: Increasing Aridity and Land-Use Intensity.

Arid lands are under increasing land use intensity and are predicted to be subject to a changing climate. For example, arid lands in the western USA are under accelerated energy development (non-renewable and renewable) and human recreation, while still supporting traditional land uses such as livestock grazing. Vast areas in this region still lack initial soil maps, or, if maps exist, they were produced at different times, at different spatial scales, and focused on less intensive land uses than the present. Climate change forecast warn of increasing aridity in this region, partly as a function of increasing temperature and a changing distribution of precipitation. Digital soil mapping and modeling are needed in this region for arid land soil mapping and assessment (biological soil crust and vegetation change; dust production) under increasing land use and increasing aridity. We propose the STEP-AWBH (“step-up”) model as a useful framework for conceptualizing these issues.