Fire regime in the Brazilian Savanna: Recent changes, policy and management

Abstract

In 2019 Brazil recorded the highest wildland fire occurrence South America has seen for the last 15 years. Added to the Amazon, the Brazilian savanna (Cerrado) faces changes in fire regimes. Climatic changes and the recent weakening of environmental law enforcement are factors, but historic and large-scale trends and drivers of fire regimes must be analyzed. We discuss ecological and policy drivers of recent changes in fire regimes in the Cerrado, in order to highlight management strategies. The Cerrado has evolved with natural fires and anthropogenic fires are also common for millennia. In the past 50 years, wildfires tend to be concentrated in the late dry season and to occur every two / three years, causing serious damage in fire-sensitive vegetation. Apart from climatic variations, the drivers of wildfires are deforestation and fire suppression policies. Nearly half of the original vegetation of the Cerrado biome has disappeared largely due to agribusiness expansion. Fire is associated with deforestation in two ways: vegetation conversion to monocultures, and lack of fire management in the remaining native vegetation. Indeed, the attempts to exclude fires from this fire-prone ecosystem disrupted traditional fire management. Fire suppression policies lead to increased wildfire risks due to fuel load and the multiplication of sources of ignition (conflicts, roads). The recent advances in Integrated Fire Management in protected areas in the Cerrado are evident. However, the recent budget cuts by the Brazilian government in environmental management and research undermine the chances of decreasing occurrences of wildfires in this biodiversity hotspot.