Wildfire and Soils
Wildfire is a powerful driver of change in the US West Region, where frequent, intensive fire is common. Increases in fire frequency, severity, and extent (i.e., fire intensification) interacting with increased human development and other anthropogenic stressors are escalating fire hazard exposure and potentially threatening soil and ecosystem health in the western US. Combustion of vegetation, litter, and soil organic matter removes vegetation, and changes dynamic soil properties (DSPs). Changes in surficial soil hydraulic properties (SHPs), driven by hydrophobicity and alterations of structural properties, can produce dramatically decreased infiltration rates and increased erodibility that result in hazardous debris flows and floods during relatively mild precipitation events. Physical and biogeochemical DSP changes and their interaction with subsequent hydro-meteorological conditions in turn influence the pattern and progression of soil and vegetation recovery. Monitoring and predicting fire impacts on DSPs is thus a critical component of understanding and mitigating future soil and ecosystem changes in the western US. Despite the central importance of the dynamics of fire impacts on soil properties, large gaps remain in our understanding of the processes contributing to differential DSP response, particularly over longer time scales spanning multiple fires (i.e., fire regime impacts).
This study focuses on the role of fire in determining DSPs across a range of temporal scales, from immediate fire impacts, to short-term (months to years) recovery, and long-term (decades to century) implications of different fire regimes in the Santa Monica Mountains, California.
Students: Ben Newcomb
Funding: This work is primarily supported by NRCS Grant #: , and has been supported in part by USDA NIFA Hatch project number CA-R-ENS-5120-H, and USDA Multi-State Project W4188.
Partners: Daniel Hirmas (Texas Tech), Tree People Land Trust