Determining Chemical Composition of Wildfire Ash Particulates

Wildfires are known to wreak havoc on ecosystems, both locally and globally. In the southwestern United States, wildfires coupled with intermittent flow from monsoonal moisture create a system where large amounts of ash (up to 3 g/L) can wash into surrounding surface waters.  Preliminary data shows that ash exposed to water greatly increases the concentration of redox active metals such as Fe and Mn in water. This may affect dissolved oxygen and pH in surface waters, creating acidic and potentially anoxic conditions.  Using characterization methods such as scanning electron microscopy coupled with energy dispersive X-ray spectroscopy (SEM/EDX) and X-ray photoelectron spectroscopy (XPS), we will determine the surface features of ash particulates of spruce, ponderosa, and aspen trees. Understanding the elemental composition and surface characterization of these ash particulates will lead to future research in determining how these redox active metals affect water chemistry over time.