NSF Award
2425431
The largest wildfires in Texas history recently burned more than 1.1 million acres (4,450 square kilometers), and have devastated livestock, crops, wildlife, homes, and ranching infrastructure across the Texas Panhandle. The effects of wildfire on sediment transport are well studied, and indicate that the absence of vegetation and hydrophobic characteristics of burned soils create conditions that intensify overland flow during subsequent rain events and can mobilize large volumes of fine sediment and initiate debris flows. However, much of this understanding of post-fire hydrologic and geomorphic processes is derived from steep (>30 degrees) and forested landscapes. Post-fire processes in the lower-slope (<1–10 degrees) grassland and shrubland landscapes of the Texas Panhandle are unknown. This project will contribute important data for management of federally classified critical habitat that hosts an endangered fish species, the peppered chub. The project supports undergraduate research at three Hispanic Serving Institutions across Texas.<br/><br/>This study is crucial for understanding the magnitude and timing of post-fire sediment transport in shrublands. A major contribution of this work will be the collection of the first post-fire sediment transport measurements in low-sloping environments like the Texas Panhandle. Measurements of sediment grain size and regolith thickness will inform the degree to which sediment transport rates are limited by stress exerted by overland flow or sediment availability. This project will also constrain the importance of vegetation as an intermittent fire-mediated storage site in low-sloping environments. Finally, measurements of suspended sediment in the Canadian River and Lake Meredith will constrain the transport timescales for fine sediment from hillslopes and tributaries to reach the sediment sink of Lake Meredith.<br/><br/>This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
