Zero-fire: Not possible nor desirable in the Cerrado of Brazil

Abstract

Fire has been a natural force modulating the vegetation of the Brazilian Cerrado since long before the first humans arrived in this region about 12 thousand years BP. Cerrado plants are, therefore, adapted to fire and some of them depend on fire to maintain their reproduction and survival. However, after the use of fire as a tool to destroy vast extents of forests in the last centuries, Brazilians in general formed a very negative opinion about the use of fire and burning native vegetation was prohibited in the country. Although this decision was effective in protecting tropical forests, the zero-fire policy has been quite negative in the Cerrado. Fire suppression in Cerrado reserves has caused a dramatic loss of biodiversity at landscape level (homogenizing the vegetation structure), at species level (leading non-tree species to local extinction) and likely at population level (sexual reproduction impaired). Furthermore, fuel accumulation over several years without fire increases the risks of catastrophic firestorms that will inevitably occur. Such negative consequences of fire suppression in the Cerrado have not been noticed even among ecologists, including myself in early career and until recently. The biased tree-and-carbon perspective of environmental campaigns and ecological studies have reinforced the misunderstanding of fire effects in Cerrado vegetation. Both neglect that the absolute majority of Cerrado plant species, as well as associated fauna and ecosystem services, depend upon open vegetation-structures which are mostly maintained by fire.