As roads penetrate into the Brazilian Amazon, the expansion of deforestation and logging have promoted fragmentation and changed forest structure, increasing the susceptibility of the forest to fire. This process is poorly understood at the regional scale because of interactions between land-use types and biophysical characteristics that differentially affect the susceptibility of forests to fire. The goal of this doctoral dissertation research project is to determine the spatial and temporal relationships between historic forest fires and human-related landscape characteristics along a gradient of drought and vegetation structure in Amazon region. Forest fires will be mapped using a historical set of Landsat scenes located along the two main road corridors in eastern Amazon. The fire maps will be used to derive the set of conditions under which forest fires have occurred and to help generate fire-probability functions for different landscapes under ENSO climatic events. These interactions will be used to build and validate a spatially-explicit model to assess the likelihood of future forest fire occurrence within the region using scenarios that include (1) increased frequency and intensity of drought provoked by El Nino Southern Oscillation (ENSO), (2) ongoing and projected road building and/or paving in the region, and (3) alternative policies designed either to promote or to constrain agricultural expansion.
This research project will help predict future forest fire occurrence within these major road corridors under a variety of scenarios. During ENSO years, forest fires in the Brazilian Amazon can double regional carbon emissions from intentional deforestation, accounting for as much as 0.329 Pg of carbon. Application of the models to be developed as part of this project can play a major role in influencing public policy by highlighting the spatial and temporal contexts that can enhance the susceptibility of Amazonian landscapes to forest fires. The results of this research also can help to direct understory fire prevention and control efforts to the areas under higher fire risk in the Amazon. The reduction of forest fires along road corridors in the region can have a positive impact on forest ecosystems by averting biodiversity loss, forest impoverishment, and carbon emissions while reducing economic and health-related costs associated with uncontrolled fires and smoke. As a Doctoral Dissertation Research Improvement award, this award also will provide support to enable a promising student to establish a strong independent research career. This award is jointly supported by NSF's Office of International Science and Engineering.