As climate change increases the frequency and severity of wildfires across the Western U.S., there is an urgent need for improved wildfire preparedness and responses.
Pyrodiversity (temporally and spatially diverse fire histories) is thought to promote biodiversity by increasing environmental heterogeneity and replicating Indigenous fire regimes, yet studies of pyrodiversity-biodiversity relationships from areas under active Indigenous fire stewardship are rare.
Fire is an integral natural disturbance in the moist temperate forests of the Pacific Northwest of the United States, but future changes remain uncertain. Fire regimes in this climatically and biophysically diverse region are complex, but typically climate limited. One challenge for interpreting potential changes is conveying projection uncertainty.
Annual burned area has increased in California over the past three decades as a result of rising temperatures and a greater atmospheric demand for moisture, a trend that is projected to continue throughout the 21st century as a result of climate change.
Fire regimes are a major agent of evolution in terrestrial animals. Changing fire regimes and the capacity for rapid evolution in wild animal populations suggests the potential for rapid, fire-driven adaptive animal evolution in the Pyrocene.
A clear understanding of the connectivity, structure, and composition of wildland fuels is essential for effective wildfire management. However, fuel typing and mapping are challenging owing to a broad diversity of fuel conditions and their spatial and temporal heterogeneity.
Large and downed woody fuels remaining behind a wildfire’s flame front tend to burn in a smoldering regime, producing large quantities of toxic gases and particulate emissions, which deteriorates air quality and compromises human health. Smoldering burning rates are affected by fuel type and size, the amount of oxygen reaching the surface, and heat losses to the surroundings.
Historically, fire has been essential in Southwestern US forests. However, a century of fire-exclusion and changing climate created forests which are more susceptible to uncharacteristically severe wildfires. Forest managers use a combination of thinning and prescribed burning to reduce forest density to help mitigate the risk of high-severity fires.
Invasions by non-native plant species after fire can negatively affect important ecosystem services and lead to invasion-fire cycles that further degrade ecosystems. The relationship between fire and plant invasion is complex, and the risk of invasion varies greatly between functional types and across geographic scales.