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Lydia P. Olander, Mercedes M. Bustamante, Gregory P. Asner, Everaldo Telles, Zayra Prado, and Plínio B. Camargo

1. Introduction In the last decade, selective logging has become an important land use in the Brazilian Amazon. Most of the Amazon forest was relatively inaccessible until new infrastructure allowed for rapid development and exploitation of forest resources ( Uhl et al. 1997 ). Now, within the Legal Amazon Basin, approximately 16 000–20 000 km 2 are deforested for agriculture or pastureland, and another 5000–15 000 km 2 are selectively logged each year ( Nepstad et al. 1999 ). Previous

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Douglas C. Morton, Ruth S. DeFries, Yosio E. Shimabukuro, Liana O. Anderson, Fernando Del Bon Espírito-Santo, Matthew Hansen, and Mark Carroll

1. Introduction Deforestation in the humid Tropics is a conspicuous change in land use with myriad impacts on global carbon (e.g., Houghton et al. 2000 ) and climate (e.g., Salati and Nobre 1991 ; Werth and Avissar 2002 ). Deforestation rates in tropical Africa, Southeast Asia, and South America have remained constant or increased over the past two decades ( DeFries et al. 2002 ), elevating the need for frequent and accurate assessment of forest loss. In Brazil, the continued expansion of

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Wilfrid Schroeder, Jeffrey T. Morisette, Ivan Csiszar, Louis Giglio, Douglas Morton, and Christopher O. Justice

:// )] over the last two decades. In particular, satellite fire detection methods have been based on a number of sensors aboard a range of orbital platforms, resulting in different manners of characterizing events at the Earth’s surface. In this paper, we focus on daily fire count data from two sensors aboard polar-orbiting satellites—the Advanced Very High Resolution Radiometer (AVHRR) and the Moderate Resolution Imaging Spectroradiometer (MODIS)—to describe fire occurrences in Brazil. The AVHRR sensor

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Michael Keller, Ruth Varner, Jadson D. Dias, Hudson Silva, Patrick Crill, Raimundo Cosme de Oliveira Jr., and Gregory P. Asner

emissions from the sandy loam Ultisols were similar to emissions from forests on Ultisol of 1.9 kg N ha −1 yr −1 in the state of Rondonia, Brazil. On both soils, interannual variability was strikingly small considering the episodic nature of N 2 O fluxes ( Crill et al. 2000 ). In comparison, annual estimates for two 1-yr periods of N 2 O fluxes for a wet tropical forest site in Queensland, Australia, using automated chambers measured about four times daily, varied by a factor of 7 ( Kiese et al. 2003

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Jeffrey T. Morisette, Louis Giglio, Ivan Csiszar, Alberto Setzer, Wilfrid Schroeder, Douglas Morton, and Christopher O. Justice

Centro de Previsão de Tempo e Estudos Climáticos (CPTEC; Center for Weather Forecast and Climate Studies) in Cachoeira Paulista, São Paulo, where fire products are designed and implemented. The MODIS INPE algorithm relies on the well-consolidated methodology of fixed threshold algorithms ( Setzer and Pereira 1991a ; Setzer et al. 1994 ; Setzer and Malingreau 1996 ; Li et al. 2001 ). INPE has successfully used this method with the NOAA AVHRR series of satellite data for nearly two decades. The

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Ted R. Feldpausch, Susan J. Riha, Erick C. M. Fernandes, and Elisa V. Wandelli

using analysis of variance (ANOVA) and regression analysis, with LAI, canopy openness, basal area, biomass, DBH, and stem density as the response variables by time after pasture abandonment (midpoint of each age class). 3. Results 3.1. Plant community transition Across the successional sequence spanning more than a decade, the pioneering vegetation converted the abandoned pastures from a low biomass, grass–forb–shrub-dominated community with species from the genera Borreria (Rubiaceae

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