HR: 11:35h
AN: B42A-06    [Abstracts]
TI: Changing Dynamics of Forest Clearing in Mato Grosso: Implications for Ecosystem Processes
AU: * Morton, D
EM: morton@geog.umd.edu
AF: University of Maryland, College Park, Department of Geography 2181 LeFrak Hall, College Park, MD 20742 United States
AU: DeFries, R
EM: rdefries@geog.umd.edu
AF: University of Maryland, College Park, Department of Geography 2181 LeFrak Hall, College Park, MD 20742 United States
AU: Shimabukuro, Y E
EM: yosio@ltid.inpe.br
AF: Instituto Nacional de Pesquisas Espaciais (INPE), Avenida das Astronautas, 1758 Jd. Granja, Sao Jose dos Campos, SP 12227-010 Brazil
AU: Pongratz, J
EM: julia.pongratz@gmx.de
AF: Ludwig-Maximilians Universitaet, Munich, Schellingstraáe 4/IV, Munich, D-80799 Germany
AU: Anderson, L O
EM: liana@ltid.inpe.br
AF: Instituto Nacional de Pesquisas Espaciais (INPE), Avenida das Astronautas, 1758 Jd. Granja, Sao Jose dos Campos, SP 12227-010 Brazil
AU: Del Bon Espirito-Santo, F
EM: fernando@dsr.inpe.br
AF: Instituto Nacional de Pesquisas Espaciais (INPE), Avenida das Astronautas, 1758 Jd. Granja, Sao Jose dos Campos, SP 12227-010 Brazil
AU: Morisette, J
EM: jeff.morisette@nasa.gov
AF: NASA Goddard Space Flight Center, Code 130, Office of Public Affairs, Greenbelt, MD 20771 United States
AU: Bounoua, L
EM: bounoua@dounia.gsfc.nasa.gov
AF: NASA Goddard Space Flight Center, Code 130, Office of Public Affairs, Greenbelt, MD 20771 United States
AB: The state of Mato Grosso has experienced consistently high rates of deforestation over the past ten years. Recent land use transitions in the state have been influenced by a growing grain-based agricultural sector. Clearings for mechanized agriculture have altered the size and timing of deforestation activities. We explore the changing dynamics of forest clearing in Mato Grosso between 2000 and 2004 with field-validated estimates of deforestation based on Moderate Resolution Spectroradiometer (MODIS) data at 250m resolution. Subsequently, we classify areas of new deforestation based on the phenological signature of post-clearing land use as pasture or mechanized agriculture. The combination of these datasets permits the quantification of relative increases in mean clearing size and definition of the timing of new clearing, stratified by post-clearing land cover. In addition, the classification of deforested areas as pasture or mechanized agriculture provides critical insight regarding climate feedbacks from changing land use in the region. Using an offline version of the Simple Biosphere Model (SiB2) modified for tropical land cover types, we evaluate the sensitivity of water and surface energy balances and temperature to transitions from forest to pasture, forest to mechanized agriculture, and pasture to mechanized agriculture. The results illustrate the important influence of land use changes that alter the photosynthetic pathway (C3 or C4) of the vegetation. Characterizing the changing dynamics of forest clearing at the agricultural/forest frontier is a critical step towards quantifying the impacts of land use change on ecosystem processes.
DE: 1600 GLOBAL CHANGE (New category)
DE: 1620 Climate dynamics (3309)
DE: 1640 Remote sensing
DE: 0400 Biogeosciences
SC: Biogeosciences [B]
MN: 2004 AGU Fall Meeting