Human Behavior and Climate Co-regulate Fire Synchrony and Its Spatial Clustering in Alberta’s Southern Canadian Rocky Mountains

Keywords: fire synchrony, fire, anthropogenic, fire regime, Rocky Mountains, human, least cost path
Session Type: Virtual Guided Poster Abstract
Day: Saturday
Session Start / End Time: 2/26/2022 05:20 PM (Eastern Time (US & Canada)) - 2/26/2022 06:40 PM (Eastern Time (US & Canada))
Room: Virtual 63

Abstract

Previous studies of fire synchrony have focused on its climate drivers, while the extent to which human behavior can influence fire synchrony remained unknown. This study investigates human influences on fire frequency and synchrony from 1600-2011 CE in the Southern Canadian Rocky Mountains. We predicted that remote forest stands persistently experienced less fire and smaller fluctuations in fire regimes than areas more accessible to people. We also predicted that fire synchrony would be highest during times of sustained and geographically concentrated human ignitions, especially in low travel cost areas. To test these predictions we compiled data from 1209 fire scar sites, distributed in 5 travel cost groups, and divided them into three time periods: indigenous, colonial, and fire exclusion. We quantified fire synchrony using a Jaccard distance matrix and used Mantel tests on the Jaccard distance matrix and a Euclidean distance matrix to examine spatial clustering. Lastly, we evaluated the strength of climate as a driver of fire by comparing PDSI and summer temperature reconstructions to fire scar ratios. Our results suggest that fire synchrony and its spatial clustering can fluctuate not only due to changes in climate, but also as a result of human land use changes.