Geotecnologias aplicadas ao mapeamento de risco de incêndio florestal no Parque Nacional da Chapada dos Veadeiros e área de entorno

Abstract

The research aimed to use geotechnologies in the mapping of the forest fire risk in Chapada dos Veadeiros National Park (CVNP) and its surroundings area. The studied area has 2376,73km2 and it is located in UTM 23S zone, between coordinates 177422 248096mE and 8420578 8473325mN, in the northeastern of Goiás State, encompassing part of the municipalities of Alto Paraíso de Goiás, Cavalcante and Colinas do Sul. To accomplish this research, we used topographic maps, with a scale of 1:100.000 edited by DSG; TM/Landsat 5 images; Ikonos images; Digital Elevation Model of the SRTM mission; daily data of the coordinates of the hotspots detected by the satellites NOAA, GOES, AQUA, TERRA and METEOSAT, available at the Image Processing Division of INPE; and climatological data of the studied area. The chosen methodology was based on studies of several authors, among them, Chuvieco and Congalton (1989); Ferraz and Vettorazzi (1998); Oliveira et al. (2004); Santos (2007); Ribeiro et al. (2008), adapted according to the characteristics of study area. Based on the most important factors to the forest fire risk, the following thematic maps were created: landuse and vegetation cover, hypsometry, slope, orientation of slopes, proximity of roads and urban areas, rainfall, average air temperature, water deficit and potential evapotranspiration. For each thematic map, we made a map of the fire susceptibility, with classes ranging from high, moderate and low. The areas of PNCV were considered with highly fire susceptibility and the surroundings area that presented the following conditions: occupied by the categories of landuse and vegetation cover Park Savanna, Grassy-Woody Savanna and Cultivated Pasture; altitudes lower than 1200m; slopes greater than 40%; hills with orientation towards the north, northeast and northwest; areas near roads, trails outside the park and urban areas; monthly precipitation less than 25mm; monthly average temperature above 26°C; monthly water deficit exceeding 90mm and monthly potential evapotranspiration exceeding 120mm. The fire susceptibility maps were integrated using a math equation to model the fire risk in the studied area, generating forest fire risk maps from June to October. The results obtained showed that the PNCV and its surrounding areas have a higher fire risk in the months of August and September (extreme risk), being the western part the most critical area. Furthermore, it is necessary to direct the attention to areas that present higher concentrations and access of people.