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RESUMOOs remanescentes florestais da Mata Atlântica têm sofrido pressões antrópicas frequentes. Essas pressões são relacionadas, principalmente, ao desmatamento e aos incêndios florestais. Por isso, o objetivo deste artigo é o desenvolvimento de um mapa geoecológico de susceptibilidade à ocorrência de incêndios no Estado do Rio de Janeiro, na escala de 1:100.000. Para esta proposta, mapas de elementos funcionais e de estrutura da paisagem (forma das encostas, radiação solar, uso da terra e balanço hídrico) foram construídos. O estudo foi conduzido utilizando o método analítico integrativo e diferentes técnicas de geoprocessamento, como Modelos Digitais de Elevação e Sistemas de Informações Geográficas. Os mapas representam três diferentes períodos: anual, seco e chuvoso. Ademais, estes mapas foram validados por meio dos dados do sensor MODIS. Os resultados proporcionaram diferentes arranjos espaciais para a susceptibilidade por meio das classes designadas como alta, média e baixa, que tiveram boa correlação com os dados de validação.Palavras-chave: mapas geoecológicos, incêndios florestais, geoprocessamento. Geoecological Assessment of Wildfire OccurencePotentiality in the State of Rio de Janeiro ABSTRACTThe remaining Atlantic Forest has frequently suffered anthropogenic pressures. These pressures are mainly related to deforestation and wildfires. The purpose of this paper was to develop a geo-ecological susceptibility map of fire occurrences in the State of Rio de Janeiro at 1:100,000 scale. To this end, maps of landscape functions and structures (landforms, solar radiation, land use and water balance) were constructed. The study was conducted using analytical integrative approach and different geo-processing techniques, such as digital elevation models and geographic information systems. These maps represent three different periods: annual, dry and rainy seasons. Moreover, they were validated through the analysis of MODIS sensor data.Results showed different spatial arrangements provided by the susceptibility of classes designated as high, medium and low sensitivity, which correlated well with the validation data.

Abstract:Throughfall has been widely studied in forests but there is a scarcity of studies that focus on the spatial variability and temporal stability of throughfall in eucalyptus plantations. We examined throughfall in a daily basis in a 2Ð5-year eucalyptus plantation in southeastern Brazil using three sample arrangements: (1) close to tree trunks (CT) and in the central point between trunks (BT), (2) four-radial layout centred in tree trunk and (3) eight-radial layout. Throughfall was spatially non-uniform and varied according to the spatial monitoring arrangement: accumulated throughfall/precipitation ratio of 146% (CT) and 85% (BT) in arrangement 1, mean throughfall of 88% in arrangement 2, 84% (hilltop) and 85% (side slope) in arrangement 3. The highest throughfall values, spatial variability and persistence of dry and wet conditions were found close to eucalyptus trunks. Often accumulated throughfall close to trunks exceeded rainfall, especially for long-duration rainfall >5 mm. The 'funnel effect' was consistently observed in all three arrangements and we speculate that the high throughfall concentration and temporal stability are related to canopy structures of eucalyptus.