HR: 0800h
AN: H51E-0412    [Abstracts]
TI: Short-term Changes in Suspended Sediment Rating Curves Following Wildfire
AU: * Desilets, S L
EM: seinloth@hwr.arizona.edu
AF: Hydrology and Water Resources University of Arizona, 1133 E. North Campus Drive, Tucson, AZ 85721-0011 United States
AU: Nijssen, B
EM: nijssen@u.arizona.edu
AF: Hydrology and Water Resources University of Arizona, 1133 E. North Campus Drive, Tucson, AZ 85721-0011 United States
AU: Nijssen, B
EM: nijssen@u.arizona.edu
AF: Civil Engineering and Engineering Mechanics University of Arizona, P.O. Box 210072, Tucson, AZ 85721-0072 United States
AU: Ekwurzel, B
EM: ekwurzel@hwr.arizona.edu
AF: Hydrology and Water Resources University of Arizona, 1133 E. North Campus Drive, Tucson, AZ 85721-0011 United States
AU: Ekwurzel, B
EM: ekwurzel@hwr.arizona.edu
AF: Union of Concerned Scientists, 1707 H St NW, Suite 600, Washington, DC 20006-3962 United States
AU: Ferre, T P
EM: ty@hwr.arizona.edu
AF: Hydrology and Water Resources University of Arizona, 1133 E. North Campus Drive, Tucson, AZ 85721-0011 United States
AB: Wildfire affects a severe pulse-change in a watershed, simultaneously altering the interdependent systems of hydrology and ecology, which rapidly and profoundly affect channel geomorphology through erosion processes. Though the initial transformation is rapid, recovery occurs over several different timescales. This work focuses on the short term and seasonal variations in suspended sediment dynamics following a wildfire in a semi-arid drainage basin in the southwestern U.S. Surface water samples were collected using an event-based sampling strategy, and sediment rating parameters were determined for individual storm events. After an initial step change to higher sediment loads, the progression of rating parameter values indicated preferential removal of fine to coarse sediment in the monsoon seasons. During the corresponding winter seasons a lower supply of sediment from the hillslopes resulted in a time invariant set of sediment rating parameters. The temporal variability in the sediment rating parameters demonstrates the importance of storm-based sampling in areas with intense monsoon activity in order to accurately characterize transport following wildfire or other rapid land-use changes.
DE: 1815 Erosion
DE: 1836 Hydrological cycles and budgets (1218, 1655)
DE: 1860 Streamflow
DE: 1862 Sediment transport (4558)
DE: 1879 Watershed
SC: Hydrology [H]
MN: Fall Meeting 2005