Anne Jacquin* - University of Toulouse, Purpan School of Engineers (France)
Thomas Devienne - University of Toulouse, Purpan School of Engineers (France)
Shawn J.M. Hutchinson - Department of Geography, Kansas State University (U.S.)
The U.S. Army Integrated Training Area Management (ITAM) program is the organization responsible for ensuring training lands are available and accessible to meet Army operational needs now, and into the future, while attempting to minimize landscape degradation. At Fort Riley (Kansas), burning grassland is the main practice to prevent shrub encroachment, to guarantee healthy stands of native grass species and to maintain accessible the training areas for the soldiers. But, because of vegetation degradation and soil erosion, one effort currently underway to support the Fort Riley ITAM vegetation monitoring activities is to clarify the importance and the role of fire on the dynamics of grassland vegetation in the training area. To this end, the fire history was reconstructed over the 12 past years (2000-2011) into a GIS and using multi-source earth observation data. The image dataset is composed of a Landsat time series (83 images), a MODIS Monthly Burned Area time series (135 images) and a MODIS 16-days Normalized Burn Ratio time series (270 images). Seasonal burned areas were detected on each time series using adapted methods. Then, according to the variability of burned areas detection quality, we combined the three data sources to produce consistent annual burned areas maps. For each pixel, the date of fire event within the year is identified. The end result of this study consists on a GIS database in which, for each pixel of the training area, information on fire frequency and seasonality during the period 2000-2011 is recorded.