Systematic approaches for ecological restoration of acidic coal mine overburden dumps in Guizhou Province, South China, using sustainable strategies to mitigate environmental degradation

Abstract

This study examines the long-term ecological restoration of acidic coal mine overburden dumps in Guizhou Province, South China, a region severely affected by soil acidification, biodiversity loss, and water contamination due to extensive mining activities. Restoration efforts employed a systematic approach integrating vegetation establishment, soil amendments, and bioremediation to rehabilitate the degraded landscapes. Application of lime (2 t ha−1) and organic compost effectively raised soil pH from 3.5 to 6.0 within 5 years, while organic amendments enhanced microbial activity and reduced heavy metal bioavailability through complexation and adsorption of metals by humic substances. The establishment of acid-tolerant plant species, such as Vetiveria zizanioides and Cymbopogon citratus, promoted soil stabilization and biodiversity recovery, increasing vegetation cover from 20% to 75% and improving the Shannon–Wiener diversity index from 1.2 to 2.8. Collaborative involvement of local communities and government agencies ensured sustainability, biodiversity enhancement, and improved water conservation. This model offers quantitative evidence and practical insights into the sustainable restoration of mining-impacted environments globally.