Quantifying, monitoring, and minimising the negative environmental impacts of mining in tropical Africa

Mining activities are distributed spatially across sub-Saharan Africa (SSA) and are in close proximity to the forestlands. Deforestation and forest degradation caused by mineral excavation is underreported especially in the SSA region, which has become a mining hub, because of its abundant mineral reserves. This study focuses on the primary and secondary impact of mining on areas of biodiversity richness, the location of 469 mines were identified and mapped in SSA and a database of mining locations was created using geospatial techniques. The dynamics of these mines were assessed to quantify how much they have expanded over time from 2001 to 2020 and the hotspots of mining were identified. Proximity analysis was conducted to ascertain the level of threat the mines pose to areas of conservation interest, results showed that the mines that are < 10 km to the protected areas had doubled in size from < 50,000 ha in 2000. The abundant reserve of key minerals in SSA has made it a major mining hub, especially at the turn of the millennium when over 260 mines were created in less than 20 years. Mining caused deforestation and forest degradation, a comparative analysis was conducted using matching to compare forest losses around locations with mines (treatments) and locations without mines (controls) over time at various buffer distances from the mines, using two sets of data: the global forest change (GFC) and the tropical moist forest (TMF). The result showed that treatments had lost 726,887 ha compared to 427,700 ha in the controls. In addition, the rates of deforestation and forest degradation pre- and post-mine creation were assessed, the rates of forest loss had increased significantly from an annual average of 1,318 ha pre-mine to 2,418 ha post-mine creation, this is an indication that mining drives forest loss. The key commodities driving deforestation in SSA are gold and copper, with annual mean loss rates of 1,462 ha and 556 ha, respectively. Sustainable mining is a prerequisite for reducing deforestation and forest degradation, and the reduction of GHG emissions attributable to mineral extraction. Furthermore, the impact of mining on the forest can be minimised through forest restoration and offsetting of biodiversity loss.