The effect of a wildfire on soils depends on how hot and how long a fire burns on the site. Hotter, slower-moving fires will have a greater effect than cooler, faster-moving fires.
Fire affects forest soils by altering physical, chemical, and biological properties. The most common effect of wildfire on soils is water repellency, which is also known as hydrophobic soil. Water-repellent soil has a limited ability to retain or absorb water, which can result in increased erosion. Some chemical changes occur after a burn, but these are usually short-lived.
