Academic Affiliation: University of Minnesota Morris
Melissa grew up in Garretson, South Dakota and currently attends the University of Minnesota Morris. Her interest in geology was sparked by her first geology class, “Minnesota Geology.” Melissa is especially interested in hydrology and how it ties to environmental issues. She likes to play video games and hang out with friends when she has time. Melissa’s presentation on her research won first price at the Amtican Indian Science and Engineering 2011 Annual Meeting.
The hydrologic impact of antecedent soil moisture and straw mulch on a burned area, Fourmile Canyon Wildfire near Boulder, Colorado
Mountainous watersheds often exhibit an increase in runoff and flash floods after a wildfire. In September 2010, the Four-mile Canyon wildfire burned in the foothills of the Rocky Mountains near Boulder, Colorado. In an effort to minimize the risk of flash floods in the canyon, Boulder County aerially applied straw mulch on high-risk areas selected primarily based on slope and burn severity. The purpose of this research is to investigate the effects of antecedent soil moisture and impact of straw mulch on the hydrologic response, specifically inter- ception, soil moisture, and runoff of a burned area. Volumetric soil moisture and storm runoff were measured from two sets of bounded, paired plots (two control, and two experimental) calibrated for 35 days starting in June, 2011, in a basin burned by the Four-mile Canyon Fire. The calibration period allowed us to better determine the relation between antecedent soil moisture conditions and the resulting runoff measurements, before straw mulch was added. Straw (5 cm thick) was added to the two experimental plots on 19 July 2011 and to the funnels of two visual rain gages in order to measure the amount of rainfall absorbed by the straw. Results from the calibration period show that runoff was greater under conditions of lower antecedent soil moisture, as anticipated. Antecedent soil moisture levels varied considerably between plots that were 12 meters apart, which indicates that calibrating for soil moisture prior to straw placement was critical. In the next phase of research, it is anticipated that total runoff will be lower on plots with straw than those without straw.