Incêndios em restingas: histórico, dinâmica, persistência e estratégias de mitigação

Abstract

The vegetation of the coastal plains along the Brazilian Atlantic coast, known as restinga, represents an ecosystem increasingly threatened by pressures related to urban expansion, land speculation, and land-use activities. These anthropogenic factors have intensified fire occurrences, rendering them more frequent and ecologically impactful. Understanding the profile and dynamics of these fire events, as well as their effects on vegetation regeneration, is essential for the development of effective management and conservation strategies. In this context, the present study analyzed the historical fire regime in restinga ecosystems of Espírito Santo State and assessed the impacts of a fire event that occurred in 2022 on both vegetation and soil properties. A historical analysis of fires from 1985 to 2023, conducted using data from MapBiomas Fire Collection 3, enabled the identification of fire seasonality, recurrence, and the most affected vegetation classes. Fire impacts on vegetation were evaluated using the Normalized Difference Vegetation Index (NDVI) and the Normalized Burn Ratio (NBR), while soil chemical analyses and floristic surveys were conducted to assess the effects of fire in a flooded restinga forest. Results indicated that fire events predominantly occurred between August and October, with wetland areas being the most affected due to the high flammability of accumulated herbaceous biomass. Vegetation regeneration varied among physiognomies, with flooded forests showing the greatest impact and limited recovery. Two years after the fire, only four tree species were identified in the burned area, indicating a negative effect on the structural diversity of the plant community. Soil analysis revealed an 11.5% reduction in carbon and organic matter stocks in the burned area, although no evidence was found that soil conditions inhibited the recruitment of new individuals. The presence of threatened species, such as Erythroxylum nitidum Spreng., highlights the heightened concern regarding recurrent fires, which may impair regeneration and promote the invasion of exotic species, thereby altering the floristic composition of the restinga. Given that most recorded fires had anthropogenic origins, mitigation strategies are critical for the conservation of this ecosystem. Preventive measures, such as the construction of firebreaks and environmental education for surrounding communities, are essential to reduce the frequency of fire events. Considering climate change and increasing anthropogenic pressure on restingas, the conservation of these environments requires an integrated approach that combines scientific research, public policy, and community engagement. Continuous monitoring of vegetation and soil, alongside the implementation of preventive and restorative strategies, will be pivotal to sustaining long-term ecological processes.