Spatial and Temporal Changes in Aeolian Redistribution of Sediments and Nutrients Following Fire

While many studies examine the role of post-fire erosion via water, fewer studies examine the role of wind as an agent of post-fire erosion. Wildfires can profoundly alter rates, magnitudes, and ecological influences of aeolian redistribution of sediments and nutrients. This study examines the influence of fire in a semi arid ecosystem using 2 years of continuous passive dust trap data in the northern Great Basin, USA. We analyse the mass flux, organic material content, grain size distribution, and geochemistry of the collected samples to trace the fingerprint of the 2015 Soda Fire through space and time. In areas not affected by fire, dust is characterized by silt sized median grains, a geochemical signature consistent with a playa source area, and spatially consistent but seasonally variable dust flux rates. Following fire, dust flux increases significantly within and near the burned area. At burned and topographically sheltered sites, dust deposition in the eighth month following fire was 190% higher than dust deposition 2 years post revegetation. Topographically exposed sites recorded only modest increases in dust deposition following fire. Analysis of organic matter indicates all dust samples (both burned and unburned) contained an average of 45% organic matter compared to a watershed average of 1.6% organic matter in soils.