Analizing post-fire boreal forest patterns with AVHRR and Canadian Large Fire Database

Resumo

As boreal forests have been diagnosed as particularly vulnerable to climate warming through changes in fire regimes, different fields of study have emerged. Vegetation recovery, phenological changes and landscape transformation after fire have been studied in Canadian boreal forests by means of Large Fire Database (LFDB) and satellite data sources, commonly according to eco-regions. A new version of Land long-Term Data Record project (LTDR v.3.2) has been recently released by recalibration of radiometric irregularities in Advanced Very-High Resolution Radiometer (AVHRR) on the different operational NOAA platforms since 1981. This allowing us to perform more accurate multi-temporal studies of burned areas from fires occurred across boreal regions for the last three decades. This work intends to find an alternative to more conventional spatial classifications like eco-regions, for future post-fire vegetation analysis in boreal forests. Different spectral indices have been analyzed by means of statistical techniques to characterize major spectral patterns from LTDR data. LFDB has been used to contrast cell radiometric and spatial coherence. Due to their ecological particularities, cells burned more than once within the period of study were considered separately. Many factors may influence boreal forest ecosystem behavior after fire (season of fire, climate conditions, cause of fire, fire type and severity). Hence, the applicability of our approach to monitoring boreal forest burned area will be discussed.