Research also highlights the influence of climate change on maintaining carbon stocks
Illegal gold mining drastically reduces carbon stocks in affected areas, with decreases of up to 50%, and increases the availability of mercury in the soil by up to 70%. The research, published in the magazine on Sunday (01.dec.2024), was carried out by Brazilian researchers who analyzed soil samples from illegal mining regions in 4 different biomes. Here is it (PDF – 5 MB).
They found that carbon release into the atmosphere averages 3.5 tons per hectare, while mercury accumulation can reach 39 kilograms per hectare.
Scientists used techniques such as chemical extraction, spectroscopy and thermogravimetry for a detailed analysis of the seasonal dynamics of these chemical elements. It was observed that the transition from the rainy to the dry season can increase the release of carbon into the atmosphere by up to 20%.
Matheus Bortolanza Soares, agronomist and post-doctoral researcher at the Luiz de Queiroz College of Agriculture of the University of São Paulo (Esalq-USP), and corresponding author of the article, added the importance of organic matter in the soil for mercury retention . “Mining and deforestation not only release CO2, contributing to global warming, but also increase the availability of mercury in the soil”said Soares.
The study also highlights the influence of climate change on maintaining carbon stocks and regulating mercury availability.
Luís Reynaldo Alleoni, Soares’ advisor, highlighted the significant contamination of mercury influenced by climatic factors, suggesting that changes in climate can worsen the transport and bioavailability of mercury, presenting greater environmental and public health challenges.
