Evaluación del impacto del incendio Nilahue-Barahona mediante índices espectrales ex-antes y ex-post

Abstract

This study assessed the impact of the Nilahue-Barahona fire, occurred during the summer of 2017, in VI Region of Chile. To do that, differentials of vegetation spectral indices were derived from Sentinel-2 optical satellite images acquired on ex-ante and ex-post dates. Differentials of vegetation state indices (of vigor, turgor and calcination) resulting from a subtraction between an image acquired before the fire and another one acquired once it was extinguished were used as a calcination severity measure of the vegetation. Meanwhile, indices’ differentials of the same indices resulting from a subtraction between the image acquired before the fire and another one acquired just one year before it were used as a recovery measure of the calcined vegetation. One year after the fire, the indices’ values showed an increase that accounted for the recovery of the burnt biomass. The mapping of the NDVI differentials obtained for the previously mentioned measures, combined with other relevant cartographic sources, contribute to explain the impact of this fire considering the preexisting vegetation communities and their topographic context. This study provides useful information to orientate subsequent selective restoration actions of the burnt ecosystems.