Effects of drought on wildfires in forest landscapes of the Western Ghats, India

Abstract

Wildland fire is an understudied yet highly important disturbance agent on the Indian subcontinent. In particular, there is uncertainty regarding the degree to which annual climate variation influences inter-annual variability in fire activity. In this study, we evaluate wildland fire at two complementary spatial scales in the southern portion of the Western Ghats mountain range (hereafter ‘Western Ghats’) in India. At the larger regional scale, we evaluate temporal and spatial variability in fire activity from 2001 to 2015. At the smaller scale, we evaluate the relationship between annual area burned and climate variation within two landscapes nested within the Western Ghats (from c. 1996 to 2015). At the regional scale, we found that most fire activity was restricted to January–March, although substantial inter-annual variation was evident. For example, in 2004, 2009 and 2012, fire activity was approximately five times greater compared with the 3 years with the lowest fire activity. The landscape-scale analysis also revealed weak to strong correlations between annual area burned and climate variation in both landscapes. Although not the only factor influencing area burned, episodes of drought could be exerting an increasingly significant effect on wildfire activity in the Western Ghats.