Estudo sobre incêndios florestais na Floresta de Miombo Reserva do Niassa-Moçambique, com base em dados de sensoriamento remoto

Os incêndios florestais são um dos principais fatores recorrentes de danos ambientais, sociais e econômicos na Reserva do Niassa. A presente pesquisa teve como objetivo entender os fatores causais e os padrões de ocorrência dos incêndios florestais na Reserva do Niassa-Moçambique, com base no conhecimento prévio do padrão de distribuição espacial e da dinâmica temporal da cobertura vegetal, utilizando dados MODIS, entre o período de 2001 a 2015. Para tal foram utilizadas bases de dados, de diferentes produtos do sensor MODIS (Moderate Resolution Imaging Spectroradiometer): produto MOD13Q1 (índice de vegetação NDVI - Normalized Difference Vegetation Index); produto MCD14ML (Fogo ativo); produto MCD64A1 (Área queimadas). Os dados meteorológicos de precipitação pluvial foram obtidos do Climate Hazards group InfraRed Precipitation with Station data (CHIRPS), a temperatura média do ar do ERA Interim; e umidade relativa foi calculada com base na equação da FAO-Penman-Monteith. Foram utilizados ainda dados topográficos (Modelo Digital de Terreno) do Shuttle Radar Topographic Mission (SRTM) para o cálculo de elevação, declividade e exposição solar. Os dados de vias de acesso e dos assentamentos populacionais foram produzidos pela CENACARTA (Centro Nacional de Cartografia e Teledeteção-Moçambique). O uso de séries temporais de dados NDVI /MODIS permitiu obter informações sobre a fenologia da vegetação, identificar diferentes tipos de cobertura vegetal da Reserva e analisar a sua dinâmica e variabilidade espaço-temporal. A sazonalidade da vegetação da Reserva apresenta ciclos bem marcados com baixos valores na estação seca e valores altos na estação chuvosa. Para análise dos padrões espaço-temporais dos incêndios florestais foram utilizados os produtos MCD14ML (Fogo ativo) e MCD64A1 (Área queimada), utilizando a estatística descritiva, análise de tendência e a densidade de Kernel. Foi observado que os incêndios florestais ocorrem entre os meses de agosto a outubro, período de maior ocorrência, e com uma dinâmica espacial que inicia a leste e se desloca para o oeste. Os incêndios ocorrem predominantemente nas florestais decíduas e de montanha. Foi também utilizada à regressão logística para a modelagem de ocorrência de incêndio florestal, com vista à identificação de locais de maior ocorrência de incêndios florestais, e identificação de fatores determinantes para a sua ocorrência. Os resultados revelaram que os principais fatores determinantes para ocorrência dos incêndios florestais na Reserva do Niassa, entre 2001 e 2015, foram fundamentalmente: cobertura vegetal, seguida de temperatura do ar e da elevação. A área de maior ocorrência de incêndios é a zona leste da Reserva. Os resultados obtidos permitiram concluir que a cobertura vegetal é um dos fatores fundamentais da ocorrência de incêndio nas florestais de Miombo. O uso dos dados MODIS, índice de vegetação, focos de incêndio e áreas queimadas demonstrou potencial no estudo de incêndios florestais na Reserva do Niassa.Forest fires are one of the main recurring factors of environmental, social and economic damages in Niassa Reserve. The objective of the present research was to understand the causal factors and patterns of occurrence of forest fires in Niassa-Mozambique Reserve, based on prior knowledge of the spatial distribution pattern and temporal dynamics of the vegetation cover using MODIS data between the period from 2001 to 2015. For this purpose, the following databases were used: MODIS sensor (Moderate Resolution Imaging Spectroradiometer): MOD13Q1 (Normalized Difference Vegetation Index); MCD14ML product (active fire); product MCD64A1 (burned area). Meteorological data on rainfall were obtained from the Climate Hazards group InfraRed Precipitation with Station data (CHIRPS), and the average air temperature of ERA Interim; The relative humidity was calculated based on FAO-Penman-Monteith equation. Topographic data (Digital Terrain Model) of the Shuttle Radar Topographic Mission (SRTM) were used for the calculation of elevation, slope and sun exposure. Data on access routes and population settlements were produced by CENACARTA (National Center for Cartography and Teledetection-Mozambique). The use of NDVI / MODIS temporal data series allowed us to obtain information on vegetation phenology, to identify different types of vegetation cover of the Reserve and to analyze its dynamics and spatio-temporal variability. The seasonality of the Reserve vegetation shows well marked cycles with low values in the dry season and high values in the rainy season. For the analysis of spatiotemporal patterns of forest fires, the products MCD14ML (Active fire) and MCD64A1 (Burned area) were used, using descriptive statistics, trend analysis and Kernel density. It was observed that forest fires occur between August and October, the period of greatest occurrence, and with a spatial dynamics that begins in the east and moves to the west. Fires occur predominantly in deciduous and mountain forests. It was also used logistic regression for modeling of occurrence of forest fire, with a view to the identification of sites of greater occurrence of forest fires, and identification of factors determining its occurrence. The results showed that the main determining factors for the occurrence of forest fires in Niassa Reserve between 2001 and 2015 were fundamentally: vegetation cover, followed by air temperature and elevation. The area with the highest occurrence of fires is the eastern zone of the Reserve. The results obtained allowed to conclude that the vegetation cover is one of the fundamental factors of the fire occurrence in Miombo forest. The use of MODIS data, vegetation index, active fire and burned areas showed potential in the study of forest fires in Niassa Reserve

Advances in Remote Sensing and GIS applications in Forest Fire Management: from local to global assessments

This report contains the proceedings of the 8th International Workshop of the European Association of Remote Sensing Laboratories (EARSeL) Special Interest Group on Forest Fires, that took place in Stresa, (Italy) on 20-21 October 2011. The main subject of the workshop was the operational use of remote sensing in forest fire management and different spatial scales were addressed, from local to regional and from national to global. Topics of the workshops were also grouped according to the fire management stage considered for the application of remote sensing techniques, addressing pre fire, during fire or post fire conditions.JRC.H.7-Land management and natural hazard

Fire

Vegetation plays a crucial role in regulating environmental conditions, including weather and climate. The amount of water and carbon dioxide in the air and the albedo of our planet are all influenced by vegetation, which in turn influences all life on Earth. Soil properties are also strongly influenced by vegetation, through biogeochemical cycles and feedback loops (see Volume 1A—Section 4). Vegetated landscapes on Earth provide habitat and energy for a rich diversity of animal species, including humans. Vegetation is also a major component of the world economy, through the global production of food, fibre, fuel, medicine, and other plantbased resources for human consumptio