Browsing by Autor "Sonaira Souza da Silva"

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    Assessment of fire hazard in Southwestern Amazon
    (Frontiers Media, 2023) Igor José Malfetoni Ferreira; Wesley A. Campanharo; Maria Lucia Ferreira Barbosa; Sonaira Souza da Silva; Galia Selaya; Luiz E. O. C. Aragão; Liana O. Anderson
    Fires are among the main drivers of forest degradation in Amazonia, causing multiple socioeconomic and environmental damages. Although human-ignited sources account for most of the fire events in Amazonia, extended droughts may magnify their occurrence and propagation. The southwestern Amazonia, a transnational region shared by Brazil, Peru, and Bolivia and known as the MAP region, has been articulating coordinated actions to prevent disasters, including fire, to reduce their negative impacts. Therefore, to understand the fire patterns in the MAP region, we investigated their main drivers and the changes in the suitability of fire occurrence for the years 2005, 2010, 2016, and 2020. We used a maximum entropy (MaxEnt) model approach based on active fire data from satellites, climatic data, and land use and land cover mapping to spatially quantify the suitability of fire occurrence and its drivers. We used the year 2015 to calibrate the models. For climatic data and active fire count, we only considered grid cells with active fire count over the third quartile. All our models had a satisfactory performance, with values of the area under the curve (AUC) above 0.75 and p < 0.05. Additionally, all models showed sensitivity rates higher than 0.8 and false positive rates below 0.25. We estimated that, on average, 38.5% of the study region had suitable conditions for fire occurrence during the study period. Most of the fire-prone areas belong to Acre, representing approximately 74% of the entire MAP region. The percentage of deforested areas, productive lands, forest edges, and high temperatures were the main drivers of fire occurrence in southwestern Amazonia, indicating the high vulnerability of fragmented landscapes extreme climatic conditions to fire occurrence. We observed that the modeling approach based on Maxint is useful for useful for evaluating the implications of climatic and anthropogenic variables on fire distribution. Furthermore, because the model can be easily employed to predict suitable and non-suitable locations for fire occurrence, it can to prevent potential impacts associated with large-scale wildfire in the future at regional levels.
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    Multi-Actor adaptation plan to cope with forests under increasing risk of extensive fires (MAP-FIRE)
    (2019) Liana O. Anderson; Luiz E. O. C. Aragão; Víctor Marchezini; Sonaira Souza da Silva; Marisa Gesteira Fonseca; Galia Selaya; Foster Brown; Cândida Leite; Guillermo Rioja-Ballivián; Eddy Mendoza
    Wildfires, caused by the interaction of social and climate systems, are currently one of the major driver of reduction of Amazonian carbon stocks and biodiversity. This process is also an important threat to the well-being of the ~25 million Amazonian inhabitants, imposing great economic losses in the impacted areas. Most Earth System Models predict increasing occurrence and intensity of droughts in the Amazon which is strongly interlinked with wildfires. The fire-related socio-environmental disaster risks are particularly critical in the tri-national frontier of Madre de Dios (Peru), Acre (Brazil) and Pando (Bolivia), known as MAP, the focal region of this study. For achieving a sustainable future, we propose a conceptual framework, based on four strategic working packages (WP): WP1- to develop a comprehensive understanding of current and future fire probability as well as quantifying the fire impacts; WP2- to produce a diagnostic and identify challenges and bottlenecks of operational and community-based strategies of wildfire risk management in the MAP region; WP3-to contribute towards the increase of risk awareness and capacity building of intergenerational social groups; and WP4- to influence conservation strategies and policies, providing technical reports for governments, improving their terminology, methods of data sharing and streams of information. Our results of a pessimistic climate†land†use projection suggest an increase of more than 100% of the area with high fire probability. Moreover, we have estimated an economic loss of approximately US$ 16 million per year due to fire impacts. Operational strategies for mitigating fire occurrence differ in the three MAP countries: in Acre, governmental actions are aligned among many environmental secretariats, which not being so structured in the two other countries. Community-based strategies will be assessed on high schools' communities. The schools' selection was defined based on their proximity with high concentrated hot pixels areas. Currently the schools' directors are being contacted to be invited for being part of the study. We expect that during the next two years, this project will contribute to identifying bottom-up initiatives and creating participatory methodologies to strengthen the science-police-citizen interface in order to mitigate mega-fires in this region.