Human-fire interactions in British Columbia: varying constraints of human-caused wildfire occurrence and geography of the wildland-development interface

Human-caused wildfires are controlled by human and natural influences, and determining the key drivers is critical for wildfire ecology and management. I examined an array of variables to determine the constraints on contemporary human-caused wildfire ignitions among fire-prone biogeoclimatic zones of British Columbia (BC). Fires in zones with high human development were strongly controlled by biophysical variables explaining conditions conducive to burning, while fires in remote zones were controlled by metrics of human activity. A coarse metric representing wildland-urban interface (WUI – areas of urban development intermingled with wildlands) was a key factor explaining human-caused ignitions, but fails to capture non-residential human development. I developed a simple-but-accurate method to map an area I define as the wildland-development interface (WDI). The WDI characterizes a broad class of human development intermingled with wildlands across BC. The WDI explains more variability in human-caused fire than does WUI, and quantifies a new geography of the human-fire interface.