Atlantic Forest loss caused by the world´s largest tailing dam collapse (Fundão Dam, Mariana, Brazil)

The collapse of Fundão dam in Mariana, Minas Gerais, Brazil, released more than 50 million cubic meters of ore tailings into the environment, representing the world's largest mining disaster. Three analyses estimating the forest loss to the ore tailings were produced soon after the collapse but the values varied threefold between them due to differences in objective and spatial resolution. Our aim was to estimate the riverside forest loss due to the flooding of the ore tailings. We analyzed Landsat Normalized Difference Vegetation Indexes (NDVI) with the digital elevation model (DEM) specific for flooded forest and limited to analyze an area floodable and contiguous from the water stream. Our forest loss quantification resulted in the same order of magnitude than the two of previous estimates. The area other than forest flooded by the ore tailings accounted for 1176.6 ha. The loss of the forest area due to the collapse was 457.6 ha and concentrated along the first 74 km from the Fundão Dam.