The past, present, and future importance of fire in tropical rainforests

The tropics bring to mind picturesque beaches and idyllic visions of seemingly endless tropical rainforests. Often overlooked, however, is that the tropics are also comprised of vast areas of savanna, montane grasslands, dry deciduous and dry thorn forests, as well as mangroves, deserts, wetlands, and a multitude of other ecosystems; many of these ecosystems burn frequently. The tropics cover one-third (33.7%) of the planet’s land surface. They contain over 40% of the world’s forests, the vast majority of all species, and are home to over 35% of the human population (Cochrane, 2009a). Satellite detections of thermal anomalies also show that the tropics experience more fires per year than anywhere else on Earth (Figure 7.1). In this region, where fire dominates many landcover types, sit the world’s richest storehouse of biodiversity within what appear to be nearly fire-immune tropical rainforests.