Mapping and monitoring lakes in the Brazilian Pantanal wetland using synthetic aperture radar imagery

1. The Pantanal wetland in South America is being threatened by human development, such as the construction of hydropower dams in the upper Paraguay River and the Hydrovia. The consequences of these developments are difficult to predict, but will potentially cause irreversible loss of habitat and biodiversity. 2. Radar satellite imagery can be used to establish baseline information that is crucial for monitoring changes in this region. In the case of the Pantanal, the pixel spacing of the imagery is a major concern if the goal is to count, map, and monitor lakes. To address this, Radarsat and JERS-1 data were acquired and used to produce a series of coarser-resolution images in order to understand the capabilities of the various resolutions to map Pantanal lake ecosystems. The simulations included resolutions of the existing JERS-1 mosaics (100m resolution) and the proposed ALOS/PALSAR mosaics (50m resolution). 3. Using the 15 in data it was found that in the Nhecolandia region of the Pantanal, only about 7% of lakes have an area larger than 0.2 km(2), 47% have an area larger than 0.05 km(2), and 50% are smaller than 0.05 km(2). Therefore, it is important to consider the substantial number of lakes smaller than 0.05 km(2). 4. The size of the errors in determining lake area depends on lake size, lake shape, and the image pixel spacing - long and small lakes have greater errors, and 100m resolution images show unacceptable errors. The error in estimating lake area associated with the pixel spacing of the Radarsat ScanSAR image is 12.5% and 25%, and for the proposed mosaics of ALOS/PALSAR it is 30% and 47% for lakes larger and smaller than 0.05 km 2 respectively. Therefore, based on simulated results, the spatial resolution of the observing SAR was an important determining factor in the capacity to discriminate small lakes in the Pantanal. Copyright (c) 2007 John Wiley & Sons, Ltd.17327728

SAR-based estimates of the size distribution of lakes in Brazil and Canada: a tool for investigating carbon in lakes

1. The size of lakes and the size distribution of lakes are important parameters controlling lake function, and how lakes interact with landscapes, the atmosphere and ecosystems. A baseline digital database of lakes could be used to improve understanding of lake function, to extrapolate lake information to regional and global scales, and as a basis for detecting future changes to lakes. 2. This paper examines the capabilities of synthetic aperture radar (SAR) imagery produced by the Japanese Earth Resources Satellite (JERS-1) to map the number and size distribution of lakes in western Arctic Canada, Central Canada and the Pantanal (Brazil). 3. For the Arctic and Pantanal, the total area found within one lake size category increases towards smaller lakes. The opposite was 2 true for the area in Central Canada. The number of lakes in the smallest size category, 0.01 to 0.1 km, was underestimated for all regions owing to the resolution of the mosaics - 100 x 100 m. The number of large lakes in the Pantanal was over-estimated through confusion with intermittent floodways that are scrubby grasslands and bare sand in the dry season and which exhibit low backscattering and therefore appear dark like lakes. 4. The lake distributions were combined with existing data to produce preliminary 2 regional estimates of carbon accumulation. Lakes may accumulate as much as 1.7 and 1.3 t C km(-2) yr(-1) for the Arctic Canadian and Central Canadian areas, respectively. No estimates were produced for the Pantanal because there are no applicable data on carbon accumulation rates available for that region. Copyright (c) 2007 John Wiley & Sons, Ltd.17328930

Programa de capacitação em ressuscitação cardiorrespiratória com uso do desfibrilador externo automático em uma universidade

A desfibrilação precoce na ressuscitação cardiopulmonar (RCP) recebe crescente destaque quanto à prioridade e rapidez. Este é um relato de experiência da implantação de um programa de capacitação em RCP, utilizando o desfibrilador em uma universidade privada. O programa em manobras básicas de RCP foi baseado nas diretrizes mundiais, envolvendo um curso teórico com demonstração prática das manobras de RCP com desfibrilador, treinamento prático individual, avaliação teórica e prática. Quanto ao desempenho dos alunos na avaliação prática, a média das pontuações obtidas pelos alunos na 1ª Etapa foi de 26,4 pontos e na 2ª Etapa a média aumentou para 252,8 pontos, já na Avaliação teórica na 1ª Etapa foi de 3,06 pontos e na 2ª Etapa a média aumentou para 9,0 pontos. A implantação desse tipo de programas contribui para a aquisição efetiva de conhecimento (teórico) e da habilidade (prática) nos atendimentos a vítimas de PCR