Impact of mining-induced deforestation on soil surface temperature and carbon stocks: A case study using remote sensing in the Amazon rainforest

The Amazon rainforest is one of the most important ecosystems on the planet; however, the environmental pressure created by anthropic activities require monitoring of this critical biome. In this study, we assessed the evolution of deforestation in an open mine pit and its impact on surface environment (i.e., temperature and carbon stocks) using remote sensing techniques. The study was carried out on an area of 11,283.3 ha in the municipality of Marabá, Pará State, Brazil, where the “Salobo” copper mine is located. A temporal analysis was conducted, using Landsat satellite images (2005–2020). Subsequently, the Land Surface Temperature (LST) and the Normalized Difference Vegetation Index (NDVI) of the deforested area were determined. Mining-induced deforestation has expanded from 0.9 ha in 2005 to 2214 ha in 2020 with an increase in surface temperature of 10 °C in the period. The temperature difference between the pit and the adjacent forest ranged from 30 to 40 °C over the 15 years, while the temperature at the forest edges rose by 4 °C. The correlation coefficient between exposed soil temperatures and mining deforestation was 0.66. CO2 emissions, increasing from 0.005 Tg CO2 in 2005 to 1.82 Tg CO2 in 2020 due to mining deforestation. The findings demonstrate the significant environmental impact of deforestation, which may also have an influence on local climate. The results can provide scientific support for public policies aimed at mitigating the issue.