Short answers, pulled from the story.
A fire regime describes the pattern, frequency, and intensity of bushfires that prevail in an area over long periods. This concept serves as an integral part of fire ecology for certain ecosystems by describing spatial and temporal patterns alongside ecosystem impacts on the landscape.
Hardesty and colleagues classified Earth's ecoregions into three groups: fire-dependent, fire-sensitive, or fire-independent. Their assessment covered a subset of Global 200 ecoregions identified by WWF for biodiversity conservation and found 46% of these regions have fire-dependent or influenced fire regimes.
The Canadian National Fire Database records large fire events since 1980 as the first nationwide database of its kind. It includes point locations for all fires larger than 200 hectares from 1959 to 1999.
Warmer climates are projected to increase fire activity and lengthen fire seasons globally due to reduced humidity and increased wind speeds. These conditions shorten fire intervals reducing time for plants to accumulate seeds before the next fire event occurs.
Bromus tectorum changed fire frequencies on Idaho's Snake River Plains significantly by making historical return intervals burn every five years instead of 60 to 110 years. This continuous fuel source makes it difficult for native vegetation to fully recover after each fire event.