The use of fire in the cerrado and Amazonian rainforests of Brazil: Past and present

Abstract

Humans have been changing the natural fire regimes in most Brazilian vegetation types for over 4000 years. Natural lightning fires can easily happen in savannas and grasslands, but they are rare in the moist rainforests. Today, anthropogenic fires are frequent in both the fire-adapted cerrado (Brazilian savanna) and the fire-sensitive rainforest. In this paper, I compare two very different biomes concerning their susceptibilities and responses to fire: the Amazon rainforest and the cerrado. I present an overview of their fire history, especially regarding human-made fires for land management, and pull together information about the use of fire by indigenous peoples in the cerrado and the Amazon, as this information is very fragmented. Accordingly, I describe how fire regimes have changed in these biomes over time due to agricultural practices and the consequences of the current altered fire regimes. After European settlement, fire frequency greatly increased in the cerrado, especially related to cattle ranching, and more recently in the more seasonal landscapes in the Amazon. In cerrado natural preserves, however, managers try to keep fire away, but wildfires eventually come and develop into destructive events. Actions to reduce biodiversity loss and environmental deterioration due to inappropriate fire management are necessary and should be very distinct in both areas: in the Amazon they would include the development of policies to stimulate fire-free, small-scale agricultural projects, and in the cerrado, sustainable use of fire for cattle ranching is possible but the regimes must be fitted to local specific features in order to avoid land degradation. In cerrado conservation areas, proper fire management programs based on scientific knowledge and the incorporation of the traditional expertise of indigenous peoples are needed to maintain the biological diversity, to maintain the ecological processes, and to reduce wildfires.