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Andrew J. Elmore, Gregory P. Asner, and R. Flint Hughes

objective was intended to prototype an operational fire-monitoring program that must eventually also include fire risk assessment and modeling. Our work also provides a more detailed understanding of how the invasive grass/fire cycle operates at regional scales on the dry leeward slopes of Hawaii. 2. Site description Hawaii is a volcanic island archipelago containing strong climatic gradients leading to a diversity of ecosystem types ranging from tropical rain forests to desert environments ( Figure 1

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

trees. Leaching of nitrate in large harvest gaps was exceptionally high, amounting to 19 g N m −2 during the first three years following harvest on podsols ( Brouwer 1996 ). Large-scale root disturbance in trenching experiments has also been shown to approximately double the emission of N 2 O during 10 weeks following disturbance ( Varner et al. 2003 ). Root mortality following logging disturbance may contribute to the increased emissions of nitrogen oxides. 4.3. Possible regional effects of

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

regenerating from pastures in central Amazônia ( Steininger 2000 ) and higher than rates reported for abandoned pastures in Puerto Rico ( Aide et al. 1995 ). Gehring et al. ( Gehring et al. 2005 ) found that a moderate increase in the intensity of land use had only minor effects on biomass accumulation, but affected forest structure with the biomass being more evenly distributed among size classes. In the upper Rio Negro of the Amazon basin biomass increased linearly through the first 40 yr following

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Tomas F. Domingues, Joseph A. Berry, Luiz A. Martinelli, Jean P. H. B. Ometto, and James R. Ehleringer

different regions, simple comparison of net primary productivity (NPP) provides limited understanding on processes governing regional carbon exchange. For example, net ecosystem exchange (NEE) measurements alone cannot clarify whether or not spatial and temporal variations in carbon fluxes are due to changes in photosynthetic assimilation, respiration, or both ( Valentini et al. 2000 ; Ehleringer et al. 2002 ). To fulfill such a gap, process-based carbon assimilation models are used to scale up fluxes

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

operational monitoring project started, supplying regional offices of the Brazilian Forest Institute (which later became IBAMA) with coordinates of fires sent by Telex machines. The results showed an unknown scale of biomass burning associated with massive deforestation in the Amazon, awakening the scientific community to the global environmental effects of such practices ( Setzer and Pereira 1991a ; Setzer and Pereira 1991b ). The monitoring system continued to improve and the user base expanded

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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

-Plus . Springer-Verlag, 512 pp . Werth , D. and R. Avissar . 2002 . The local and global effects of Amazon deforestation. J. Geophys. Res. 107 . 8087, doi:10.1029/2001JD000717 . Wessels , K. J. , R. S. DeFries , J. Dempewolf , L. O. Anderson , A. J. Hansen , S. L. Powell , and E. F. Moran . 2004 . Mapping regional land cover with MODIS data for biological conservation: Examples from the Greater Yellowstone Ecosystem, USA, and Pará State, Brazil. Remote Sens. Environ. 92

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Gregory P. Asner, David E. Knapp, Amanda N. Cooper, Mercedes M. C. Bustamante, and Lydia P. Olander

Atmospheric Correction Now (ACORN) algorithm for hyperspectral data (ImSpec, Inc., Pasadena, California), and convolved to six Landsat ETM+ optical channels. These green vegetation spectra thus inherently included the variable effects of intra- and intercrown shadowing, which are prevalent in tropical forests ( Gastellu-Etchegorry et al. 1999 ). In Amazonia, shade fractions average 25% cover in humid tropical forests, but the variance is high with standard deviations of 12% or more ( Asner and Warner 2003

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

1. Introduction Biomass burning plays an important role in various aspects of the global climate system, largely because of the effects of trace gas emissions from biomass combustion and the resulting changes to the radiation and energy budget ( Crutzen and Andreae 1990 ; Lenoble 1991 ; Artaxo et al. 1998 ; Eck et al. 1998 ; Ross and Hobbs 1998 ). Of the total number of fire events observed every year, most occur in the Tropics ( Hao and Liu 1994 ; Dwyer et al. 2000 ), due to the

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

research on logging impacts in tropical forests focuses on silvicultural aspects, such as damage to remaining trees, regrowth rates, and changes in species composition. Studies are in progress in the Brazilian Amazon to assess the extent and impacts of logging on a regional scale using remote sensing ( Asner et al. 2002 ; Asner et al. 2004a ) and eddy flux towers ( Saleska et al. 2003 ; Rice et al. 2004 ). However, only a handful of the previous or current studies address the potential for changes in

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Eraldo A. T. Matricardi, David L. Skole, Mark A. Cochrane, Jiaguo Qi, and Walter Chomentowski

and affect the postharvest forest recovery to varying degrees. Poor felling techniques can kill up to six trees for every one that is cut down. The remaining forests become highly degraded, with up to 40%–50% of the canopy cover being destroyed by the logging operations ( Uhl and Vieira 1989 ; Veríssimo et al. 1992 ). The effects of unmanaged selective logging include increased fire susceptibility ( Holdsworth and Uhl 1997 ), damage to nearby trees and soils ( Johns et al. 1996 ; Veríssimo et al

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