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The role of fire on soil mounds and surface roughness in the Mojave Desert

Christopher E. Soulard·Todd C. Esque·David R. Bedford·Sandra Bond
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Abstract

A fundamental question in arid land management centers on understanding the long-term effects of fire on desert ecosystems. To assess the effects of fire on surface topography, soil roughness, and vegetation, we used terrestrial (ground-based) LiDAR to quantify the differences between burned and unburned surfaces by creating a series of high-resolution vegetation structure and bare-earth surface models for six sample plots in the Grand Canyon-Parashant National Monument, Arizona. We find that 11 years following prescribed burns, mound volumes, plant heights, and soil-surface roughness were significantly lower on burned relative to unburned plots. Results also suggest a linkage between vegetation and soil mounds, either through accretion or erosion mechanisms such as wind and/or water erosion. The biogeomorphic implications of fire-induced changes are significant. Reduced plant cover and altered soil surfaces from fire likely influence seed residence times, inhibit seed germination and plant establishment, and affect other ecohydrological processes.

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Christopher E. Soulard, Todd C. Esque, David R. Bedford, Sandra Bond. 2012-05-20. The role of fire on soil mounds and surface roughness in the Mojave Desert. https://doi.org/10.1002/esp.3264

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