POST-FIRE VEGETATION, SOIL, AND STREAM PROCESSES IN URBAN MEDITERRANEAN SYSTEMS (Invited Presentation)

Wildfires are increasing in size and extent across many parts of the United States. After wildfire, secondary impacts can pose hazards to waterways and infrastructure, including flooding, sedimentation, and degraded water quality. Fire effects are related to fire frequency, severity and timing, which are generally driven by climate conditions, vegetation type, fuel loads, and landscape conditions. These can be exacerbated by climate change and human interaction. For example, human-ignited fires, large fuel loads, and non-native vegetation have made urban streams and rivers into corridors for fire movement. The goal of this research is to understand and predict changes in vegetation, soil, and stream processes that occur after urban fires in southern California. Processes in riparian zones are emphasized due to their role in controlling the impacts of fires by regulating the release of pollutants and the erosion of soil into streams. However, these riparian processes are poorly understood in burned urban stream corridors. Following the Del Cerro brush fire in San Diego, remote sensing methods are used to evaluate burn severity and document changes in erosion, which are related to riparian vegetation and hydrologic conditions. This work will provide new information that can be used to provide guidance for risk assessments, policy, and preparedness for urban watersheds vulnerable to fire hazards.