Integrated Mining and Reclamation Practices Enhance Sustainable Land Use: A Case Study in Huainan Coalfield, China

Abstract

In the coal-grain composite area (CGCA) of eastern China with a high groundwater table (HGT), underground coal mining subsidence has caused extensive submergence of farmland, posing a significant threat to regional food security. Currently, land reclamation techniques in mining subsidence areas primarily focus on post-mining reclamation (PMR) of stable subsidence land with a low reclamation rate. This study investigated the application of concurrent mining and reclamation (CMR) technology for unstable subsidence land in a representative HGT mining area, namely the Guqiao Coal Mine in the Huainan Coalfield. Firstly, mining subsidence prediction and geographic information technology were employed to simulate the spatio-temporal evolution of dynamic mining subsidence, taking into consideration the mining plan. Subsequently, phased reclamation parameters were quantitatively designed by integrating the dynamic mining subsidence and surface reclamation measures. Lastly, scenario simulations were conducted to discuss the effectiveness of CMR in comparison with non-reclamation (NR) and PMR. Additionally, reclamation and ecological restoration strategies for coal mining subsidence areas with comprehensive governance modes were proposed. The findings indicated that mining activities have led to a reduction in both the quantity and quality of original farmland, with 70% of the farmland submerged and rendered uncultivable. In contrast to PMR, which achieved a reclamation rate of 29%, CMR can significantly increase the farmland reclamation rate to 69% while also prolonging the service life of farmland. This study provides theoretical support and technical references for promoting sustainable mining practices, protecting farmland, and facilitating the high-quality development of coal resource-based cities.

A Calculation and Optimization Method for the Theoretical Reclamation Timing of Cropland

“…This technology advocates using mining subsidence control technology to excavate coal resources underground and implement reclamation measures on the surface before or during mining [4,26]. Relevant studies have shown that this technology can improve the land reclamation rate [4,18,[27][28][29]. This technique requires engineers to implement reclamation measures before cropland waterlogging occurs to salvage more soil.…”

The role of red mud and cow manure for sustainable post-gold mining land rehabilitation

“…It is imperative to conduct research on sustainable postgold mining land rehabilitation, with the goal of minimizing losses arising from land degradation and maximizing land productivity. A suitable amelioration technology that aligns with site conditions can play a key role in enhancing soil fertility and land quality (Feng et al, 2023;Setiawan et al, 2021). Consequently, judicious stewardship of post-mining terrains is essential in attenuating detrimental environmental repercussions and advocating for sustainable mining protocols.…”