Comparative analysis of natural and anthropogenic wildfire regimes in Mainland Southeast Asia

Clear differentiation between natural and man-caused fires (NFs and MFs), and understanding their distinct behaviors and drivers, is essential for predicting fire dynamics and assessing impacts. However, these efforts remain challenging due to scarce direct ignition observations, requiring reliance on large-scale geospatial datasets and sophisticated analytical frameworks. This study classifies NFs and MFs across Mainland Southeast Asia (MSA) (2000–2020) to enhance understanding of their distinct patterns and inform mitigation strategies. By integrating land cover data with the Human Footprint Index (HFP) and lightning fire probability, we delineated NF- and MF-dominated regions across MSA. We found that the proportion of identified human-caused fire regions (61.5%) was substantially higher than that of natural fire regions (38.5%). Spatial-temporal analyses revealed divergent trends: a statistically significant decline in NFs contrasted with escalating MF activity, showing a close connection with population growth and concurrent habitat fragmentation. El Niño-induced thermal anomalies further amplified wildfire frequency during drought periods. Notably, MFs showed a stronger correlation with moisture deficits and greater sensitivity to Niño 3.4 index variability compared to NFs. To mitigate wildfire risks, policy efforts should prioritize (1) real-time forecasting systems for extreme aridity and (2) accelerated transition from slash-and-burn agriculture practices to sustainable land-use alternatives.