Hot fire, cool soil Available to Purchase

Wildfires around the planet burn an average of 3.7 million km² of vegetation annually and can leave landscapes scorched, barren, and vulnerable to erosion and flooding. According to the literature, the more vegetative fuel, the more intense the fire, the hotter the soil, and the more severe the damage to fragile roots, seeds, and microbes. But that understanding is based on laboratory studies and prescribed burns in small fields. An experiment led by Cornell University’s Cathelijne Stoof, who at the time was working at Wageningen University in the Netherlands, now provides evidence that in more heterogeneous conditions the opposite may occur—the hotter the fire, the cooler the soil. To study the effects of landscape and fire dynamics on soil temperature, the group mapped a 0.1-km² shrub-covered watershed in Portugal, installed 52 thermocouples throughout the region, and then set it ablaze. Although the most thickly vegetated areas burned at...