Impact of topographic features on the distribution of fire based on MODIS data in Inner Mongolia, northern China

Understanding the interplay between the distribution of fire and the topographic features is a fundamental concern for holding the regularity of fire distribution and designing strategic fire management plans. In this study, we analyzed MODIS thermal anomalies (MOD14 and MYD14) and DEM data to explicitly quantify relationships between fire and topographic features, with a particular focus on Inner Mongolia during the period of 2000 to 2015, using a moving-window resampling approach. The results showed that: 1) with the support of mean change-point analysis, the curve appeared at the inflection point at the grid of 8×8 mesh size (0.52 km²) for Inner Mongolia relief amplitude; 2) there was a significant terrain gradient in distribution pattern of fire. It was found that the number of hotspots increased at first and then decreased with the rise of elevation, while decreased with the increase of slope and relief amplitude; 3)fire easily occurred in plat areas, the areas with elevation between 80 and 700 m, slope between 0° and 7° and relief amplitude between 1 and 70 m. Human activities are frequent in these plat areas, which provides the opportunity for the fire; 4) grassland was most affected by fire in terms of hotspots, followed by agricultural areas, forests and others. Human beings' frequent actions and rich combustible are the main reasons for fire on grass.