Andres R. Sanchez
Department of Hydrology and Atmospheric Sciences, The University of Arizona, Tucson, Arizona
Wildfires represent one of the largest disturbances in forested areas. The number, size and severity of wildfires have significantly increased in the western United States since 1990. High occurrence of wildfires are observed during the summer months where mean temperatures are elevated. It has been predicted that the frequency, severity, and area burned by wildfires will increase in the Southwest United States with progressive increasing of temperatures and drought. When a fire occurs, nutrients that were taken up by the biomass (e.g. vegetation) are released from the burned vegetation and transported downstream via washoff and shallow subsurface flow. After fire, ash deposits on hillslopes may form a large store of particulate carbon and contain elevated concentrations of various nutrients, trace elements, as well other potential contaminants that are constantly released into the surface water.
It is crucial to understand how those fires affect the flux of solutes available from these sources in the critical zone, which is the area ranging from the top of the vegetation canopy to the bottom of free flowing groundwater where mass and energy are exchanged between the regolith, biosphere, and atmosphere. The main focus on this study is to understand how these wildfires affect the overall water quality of surface water and groundwater in forest catchments.