Preparation of technosol based on coal gangue and its impact on plant growth in coal mining area

Coal gangue, a byproduct of coal mining, is traditionally considered a nuisance. Recent research has begun to explore its potential for soil improvement and land reclamation through controlled pot experiments. However, its usage in soil matrices remains below 50% in most studies. To address these issues, this study investigates the preparation and utilization of coal gangue in technosols, with a focus on its impact on plant growth under natural conditions. The study was conducted at the Suntuan coal mine, located in the Huaibei mining area of eastern China. Results showed that technosols prepared with a high coal gangue dosage ranging from 60% to 100% could support optimal growth of maize (Zea mays L.) with low pollution risk. The impacts of the amount of coal gangue and organic fertilizer on the improvement of technosol quality and the promotion of vegetation growth were significant. The preferred preparation method involved a combination of coal gangue, soil, biochar, microbial agent, water-retaining agent, and organic fertilizer at 60:40:1:0.0025:0.01:5. Overall, our study emphasizes the potential of coal gangue for sustainable land reclamation and environmental benefit. Through optimized technosol preparation and effective utilization of functional materials, our research contributes to eco-friendly practices in coal mining areas.