The Chemical Signature of Dust in the Reynolds Creek Experimental Watershed, Idaho

Aeolian or wind-blown sediment redistribution in the northern Great Basin impacts landscape development, soil depths/variations, and wind erosion of semi-arid rangeland surfaces. This study evaluates the importance of aeolian processes for carbonates found in soils and analyzes the organic material (specifically post-fire) in dust deposits to help characterize aeolian processes on soils in Reynolds Creek Experimental Watershed (RCEW) southwest of Boise. Researchers hypothesize that the source of calcium found in RCEW soils must be deposited through aeolian mechanisms, because the alternate bedrock source of calcium is inconsistent with corresponding soils. It’s important to understand how calcium is introduced to RCEW soils because soils provide storage for carbon in the form of calcium carbonate. Past dust collections from passive (vertically deposited) dust traps at RCEW are analyzed for elemental and nutrient concentrations, grain size distribution, and organic material concentrations. These analyses will build upon our understanding of calcium contributed to soils by dust and indicate any post-fire signal of organic material. This study is an extension of past research, which observed suspension and deposition of local material following wildfires with increased organic material, particle size, and mass flux. Future research will use new dust capture technology to evaluate horizontal aeolian transport