Karina Custódio*
20 million hectares of native Cerrado vegetation were affected by fires that started in areas of deforestation, reveals an article published with the participation of IPAM (Amazon Environmental Research Institute). The research was carried out in five states with high deforestation rates (Mato Grosso, Maranhão, Tocantins, Piauí and Bahia) over an 18-year period (2003 to 2020).
After deforestation, fire is used to ‘clear’ remnants of vegetation and prepare the area for other activities. However, the survey shows that 93% of the territory affected by fires that started in deforested areas in the period “escaped” into areas of conserved vegetation, while 7% were restricted to deforested areas.
Map of the area analyzed
Map: Gian Luca Spadoni
The research is the first to examine the relationship between deforestation and fire over a large area of land in the Cerrado. A total of 105.1 million hectares were analyzed, making it possible to establish a correlation between the two phenomena.
“The research shows that fire is not restricted to deforested areas. It escapes into the surroundings, reaching vegetation that has not been converted. Even if unintentionally, these fires impact native vegetation. The tendency is for these escapes to increase even more as the climate emergency progresses. These results reinforce the need to eliminate ignition sources, which makes it essential to reduce deforestation as one of the main strategies for limiting the area affected by fire in the biome,” says Ana Carolina Pessôa, a researcher at IPAM and one of the authors of the publication.
Fires related to deforestation behaved differently from those not associated with vegetation suppression, burning at the end of the biome’s dry season, when the vegetation is more flammable, thus increasing the risk of the fire escaping.
Private properties concentrate the largest burnt area
With 14.7 million hectares of burned vegetation, private properties were the most affected by fires related to deforestation – 27% of their native vegetation was consumed by this type of fire. This was followed by public sustainable use areas, with 1.4 million hectares burned by deforestation-related fires.
Indigenous lands and fully protected conservation units registered some of the lowest rates of deforestation, with 81,500 hectares and 22,700 hectares converted, respectively. Even so, they were hit by fires that escaped deforestation: on indigenous lands, 1.2 million hectares of vegetation were burned – the equivalent of 16% of their vegetated area. In full protection conservation units, 362,000 hectares were burned, or 12% of the native vegetation.
Tocantins concentrates largest burned area
Tocantins had the highest rate of fire escapes from deforested areas among the states – 96.5% of the burned area was native vegetation, burning 6.4 million hectares, 33.1% of its native vegetation. Mato Grosso comes next, with 96.8% and 4.8 million hectares burned, and Maranhão with 92.2%, a total of 4.5 million hectares.
Bahia was the only state in which the deforested area was greater than the burned area related to deforestation. 86.6% of the area burned by fires started in deforested areas affected native vegetation.
How the survey was carried out
To identify whether the fire originated from deforestation, the area of vegetation suppressed in the period was compared with the area burned. Fires related to deforestation were considered to be those that started in or within 1 km of deforested areas, and which occurred within two years of the vegetation being converted.
The data used in the analysis comes from PRODES (Project for Satellite Monitoring of Deforestation in the Legal Amazon) Cerrado, MapBiomas and GFA (Global Fire Atlas), which provides information on the origin of fires.
The area analyzed brings together regions that faced deforestation peaks at two points in time: between the 1970s and 1990s in Mato Grosso, and between 2007 and 2008 in the states of MATOPIBA (a region that encompasses part of the states of Maranhão, Tocantins, Piauí and Bahia). Considered the last agricultural frontier of the Cerrado, the region faced the highest deforestation rates in the country in 2023 and 2024.
IPAM* communications analyst
Cover photo Sara Leal*