A Review of Wildfire Effects on Soils, Hydrologic Processes and Water
Jingyi Cheng, MLWS 2021
Wildfire is a natural process that has happened regularly for millions of years and brings both positive and negative impacts to the forest environment. In recent decades, climate change has become a critical element in increasing the risk and extent of wildfires globally. Climate change increases temperature and reduces precipitation, extending the fire season and expanding the burning area. Wildfire affects soil physical properties (e.g. texture, colour, pH, hydrophobicity), chemical properties (e.g. organic matter, macro and micro-nutrients), as well as soil biota (e.g. invertebrates and micro-organisms). Intense wildfires further cause infiltration rate reduction and high surface runoff. Ash and sediments transported with surface runoff contaminate water quality, resulting in damage to the aquatic organisms and drinking water treatment issues. Effects of wildfire on forest soil, hydrologic processes and water are site-specific and complex. The extent of wildfire impacts depends on the intensity and severity of the fire, burning season, pre-fire and post-fire environmental conditions, climate pattern, vegetation types and many other factors. Studies of wildfire effects are diverse, but comprehensive reviews that assemble findings in the three fields are still lacking. Therefore, the purpose of this paper was to review the wildfire effects on forest soil, the hydrologic processes and water quality based on existing literature.