Pyrogeography across the western Palaearctic: A diversity of fire regimes

Abstract

AbstractAimThe aim was to characterize fire regimes and estimate fire regime parameters (area burnt, size, intensity, season, patchiness and pyrodiversity) at broad spatial scales using remotely sensed individual‐fire data.LocationWestern part of the Palaearctic realm (i.e., Europe, North Africa and the Near East).Time period2001–2021.MethodsInitially, I divided the study area into eight large ecoregions based on their environment and vegetation: Mediterranean, Arid, Atlantic, Mountains, Boreal, Steppes, Continental and Tundra. Next, I intersected each predefined ecoregion with individual‐fire data obtained from remote sensing hotspots to estimate fire regime parameters for each environment. This allowed me to compute annual area burnt, fire size, fire intensity, fire season, fire patchiness, fire recurrence and pyrodiversity for each ecoregion. I related those fire parameters to the climate of the ecoregions and analysed the temporal trends in fire size.ResultsFire regime parameters varied across different environments (ecoregions). The Mediterranean had the largest, most intense and most recurrent fires, but the Steppes had the largest burnt area. Arid ecosystems had the most extended fire season, Tundra had the patchiest fires, and Boreal forests had the earliest fires of the year. The spatial variability in fire regimes was largely explained by the variability of climate and vegetation, with a tendency for greater fire activity in the warmer ecoregions. There was also a temporal tendency for large fires to become larger during the last two decades, especially in Arid and Continental environments.Main conclusionThe fire regime characteristics of each ecoregion are unique, with a tendency for greater fire activity in warmer environments. In addition, fires have been increasing in size during recent decades.