Mining in Ghanaian Forest Reserves: Impacts on Forest Cover, Biodiversity and Carbon Stocks

Abstract

<title>Abstract</title> Ghana recently legalized mining in forest reserves but the impacts of this policy shift on forest cover, biodiversity and carbon stocks are not well documented. We analysed forest cover dynamics between 2018 and 2023 in the Oda River Forest Reserve and inventoried data from 12 plots in non-mined and mined (low, moderate and heavily) sites for its consequences on biodiversity and carbon stocks. Forest cover declined by 5.9%, shrinking from 16,959.89 ha in 2018 to 15,952.82 ha in 2023, while illegal mining expanded astronomically by 1,917.6%, increasing from 52.78 ha to 1,059.85 ha, with the most rapid expansion occurring between 2022 and 2023. The study revealed significant reductions in plant species richness and diversity across trees, shrubs, and climbers in mined areas, with heavily mined zones exhibiting a complete absence of vegetation. The Shannon diversity index and structural attributes such as tree height and diameter also significantly declined, reflecting the widespread ecological disruption caused by mining activities. Non-mined areas demonstrated higher biodiversity (S = 13.33, H = 2.41), greater structural complexity, and maintained the highest carbon stocks (689.11 Mg C ha^{− 1}), emphasizing their role in mitigating climate change. In contrast, heavily mined areas exhibited complete carbon loss, resulting in substantial potential CO₂ emissions (2,522.15 tCO₂e). Our results demonstrate the urgent need for effective land management policies, enforcement of mining regulations, and restoration efforts, including reforestation with native species. Addressing mining in forest reserves is critical to preserving biodiversity, mitigating climate change, and ensuring the resilience of forest ecosystems.