Post-fire Response of Little Creek Watershed: Evaluation of Change in Sediment Production and Suspended Sediment Transport

<p>The Little Creek watershed was assessed to identify changes in event-based suspended sediment export and determine the factors contributing to sediment production the first year following the Lockheed Fire in 2009. The amount and volume of near-stream sediment sources were found to decrease, while an increase in hillslope sediment production was documented. High intensity, short duration rainfall (up to 87 mm/hr for 10 minute duration) initiated extensive rilling and minor channel-derived debris torrents originating from the upper south facing slopes. Rainfall simulations, hillslope erosion plots, and soil infiltration tests indicated that fire produced soil water repellency, the lack of ground cover, steep slopes, and high soil burn severity were the most influential factors contributing to hillslope erosion. Contrary to results reported in other western U.S. studies, regression analyses determined that the effect of fire significantly decreased suspended sediment concentrations with higher flows at North Fork and Upper North Fork monitoring stations. The effect of the fire did not produce increases in stormflow volumes and event sediment load, likely due to the fact near-stream sediment contribution was minimal and the majority of hillslope-derived sediment sources were not hydrologically connected. This study provides valuable information for landowners and land managers to understand how a coastal redwood dominated watershed responds to wildfire and prepare post-fire mitigation efforts following future wildfires.</p>

Name thesis:degree_name

MS in Forestry Sciences

Discipline thesis:degree_discipline

Natural Resources Management

Year dc:date.available

2013

Author dc:creator

• Loganbill, Andrew Wood

Contributors dc:contributor

• Brian Dietterick
• College of Agriculture, Food, and Environmental Sciences

• wildfire
• hydrologic response
• rainfall intensity
• hillslope erosion
• spr_stu
• Other Forestry and Forest Sciences

Identifier

10.15368/theses.2013.68

OAI identifier oai:identifier

oai:digitalcommons.calpoly.edu:theses-2061