Courtesy of Robert Faust
Wildfires destroyed more than 3,600 homes and 750,000 acres of southern California's chaparral forests in 2003. Although these ecosystems are adapted to frequent, low-intensity burns, many ecologists say that fuel-load buildup due to years of fire suppression has led to catastrophic blazes. Brent Roath, a soil scientist stationed at the Sierra National Forest, says that once a fire is extinguished, assessing the damage and implementing necessary treatments "can take weeks, if it's a big incident like the southern California fires."
These infernos leave behind a charred, barren landscape, susceptible to erosion by wind and rain. Soil structure normally retains water, but soil hydrophobicity, caused by the distillation of volatile oils and aromatics from burning trees, prohibits absorption. Soil-dwelling invertebrates, bacteria, and fungi recycle essential nutrients such as carbon, nitrogen, and phosphorus, but increases in temperature and pH disrupt natural cycling. Fast-moving, low-intensity burns increase nutrient availability, ...
