Post-wildfire assessment of vegetation regeneration in Bastrop, Texas, using Landsat imagery

Abstract

Monitoring post-wildfire vegetation trends is key to the management and sustainability of forest ecosystems. The 2011 Bastrop Complex Wildfire provided a unique opportunity to study the effects of wildfire on vegetation in an infrequently studied locale for wildfire research. Using Landsat 5 Thematic Mapper and Landsat 8 Landsat Data Continuity Mission imagery, we investigated the relationship between burn severity and vegetation regeneration while exploring changes in spatial vegetation patterns resulting from the wildfire. Mean normalized difference vegetation index (NDVI) levels increased substantially in the three years after the fire, indicating that vegetation has recovered rapidly in the Bastrop forest, though the overall course of recovery is still uncertain at these early stages. At an aggregate level, the substantial vegetation regrowth in the early post-wildfire years was broadly consistent with previous research, but NDVI trajectories behaved divergently when evaluated by burn severity level. Heavy and moderate burn severity areas experienced a net decline in NDVI during the third year, while more lightly burned areas demonstrated the greatest degree of overall recovery. Continued research will be required to evaluate the long-term effects of the wildfire and determine whether these trends are temporary or lasting.