Analysis of changes in physical parameters of surface derived from biomass burning in Rondônia State

The main objective of this work is to analyze the impacts in soil temperature and short-wave radiation balance derived from biomass burning in Rondônia State for 2000-2011 years, using RegCM4 for meteorological modeling. This model requires some input data such as land use and land cover maps (with and without burned areas) and physical parameters such as the surface albedo (separated in photosynthetic active radiation and in shortwave infrared reflectance), leaf area index and the fraction of vegetation cover. Thus, the land use and land cover maps were updated from MCD12A1 product of Moderate Resolution Imaging Spectroradiometer (MODIS) sensor. The MOD09 and MYD09 products of MODIS were utilized for the burned areas mapping, obtained from the Linear Spectral Mixture Model (SLMM), segmentation of shadow fraction images and manual editing. The surface albedo and the fraction of vegetation cover data were collected in the fieldwork with FieldSpec Pro equipment and leaf area index was obtained from MYD15A2 and MOD15A2 of MODIS products. The results indicated that the burned areas exhibit significant variability in Rondônia State, especially in 2005, 2010 and 2004 years, and these burnings occur in majority in areas that already have some type of use (areas of vegetation extraction, large animals livestock areas and diverse permanent crops). The albedo values showed a decrease of 16% with the occurrence of a fire, a factor that causes changes in short-wave radiation balance. These changes occasioned the elevation of soil temperature, which can reach maximums values of 10°C per day, resulting in significant changes in different climatic variables that may alter the local and regional climate. (AU)