Incêndios florestais como fator de mudança na dominância do bambu em florestas abertas no leste do Acre

With the increase of frequency of extreme droughts in Amazonia, there is also an increase in the occurrence of forest fires. There is change in the forest after the fire through the expansion of bamboo in the forests. However, our knowledge about the relation between bambu dominance and forest fire is still limited. The objective of this study was to evaluate the bamboo''''s dominance in open forest with bamboo affected by wildfires in 2005 and 2010 in the State of Acre, using remote sensing techniques and forest inventory. The mapping of forest fire scars was performed with Landsat images processed in the Claslite software. After the identification of scars, this data was overlayed with a map of open forest with bamboo, in order to select areas for forest inventory. The following parameters were evaluated: Total number of bamboo culms/m2, the number of living trees > 10 cm diameter at breast height (DBH) and mortality rate. The normalized difference of vegetation index (NDVI) was used to analyze vegetation change after fire. There were significant differences observed in both NDVI and forest inventory data between unburned forest and those burned forests of five years old and ten years old. The burned forests showed higher NDVI compared to the unburned forest. We observed the larger number of bambu culms in the burned forests than in the unburned forest. Based upon the results of these analyses, it is possible to concluid that forest fires beneficiate the process of bambu colonization.