Fire significantly affects species composition, structure, and ecosystem processes in boreal forests. Our study objective was to identify the relative effects of climate, vegetation, topography, and human activity on fire occurrence in Chinese boreal forest landscapes. We used historical fire ignition for 1966-2005 and the statistical method of Kernel Density Estimation to derive fire-occurrence density (number of fires/km2). The Random Forest models were used to quantify the relative effects of climate, vegetation, topography, and human activity on fire-occurrence density. Our results showed that fire-occurrence density tended to be spatially clustered. Human-caused fire occurrence was highly clustered at the southern part of the region, where human population density is high (comprising about 75% of the area's population). In the north-central areas where elevations are the highest in the region and less densely populated, lightning-caused fires were clustered. Climate factors (e.g., fine fuel and duff moisture content) were important at both regional and landscape scales. Human activity factors (e.g., distance to nearest settlement and road) were secondary to climate as the primary fire occurrence factors. Predictions of fire regimes often assume a strong linkage between climate and fire but usually with less emphasis placed on the effects of local factors such as human activity. We therefore suggest that accurate forecasting of fire regime should include human influences such as those measured by forest proximity to roads and human settlements.
|Number of pages||9|
|Journal||Science of the Total Environment|
|State||Published - Sep 5 2014|
Bibliographical noteFunding Information:
This research was funded by the National Natural Science Foundation of China (Grant No. 31200362 and 41201185 ) and the 973 Project of the Ministry of Science and Technology of China (Grant No. 2011CB403200 ). We thank two anonymous reviewers for their comments which greatly improved earlier versions of this manuscript.
© 2014 Elsevier B.V.
- Boreal forest
- Fire occurrence
- Relative importance
ASJC Scopus subject areas
- Environmental Engineering
- Environmental Chemistry
- Waste Management and Disposal