Advancements in Fertilizer Conservation and Ryegrass Growth in High-Altitude Copper Tailings Regions: Facilitating Green Restoration and Ensuring Sustainable Utilization.

The study involved conducting soil column simulation tests and pot experiments to explore the impact of applying five different proportions of amendments on fertilizer retention and ryegrass growth characteristics in copper tailings at high altitudes. The results demonstrated that fertilization with these varying proportions of amendments significantly enhanced the physical structure and nutrient content of the copper tailings, leading to a notable difference compared to the control group. Following application of the amendment to the surface layer (0–20 cm) of the tailings, nitrogen, phosphorus, and potassium levels declined with increasing leaching times; however, even after six leaching times, the nutrient content still met afforestation planting soil fertility requirements. In contrast, nutrients in the lower layer (20–40 cm) without amendment initially rose significantly during leaching but ultimately exhibited less fertility increase compared to the control group. This suggests that pure copper tailings have limited capacity for nutrient absorption from leaching solutions and poor fertilizer retention effects. Ryegrass thrived on improved tailings, showing a positive correlation between its growth and organic matter content as well as available potassium, available phosphorus, and alkali-hydrolyzed nitrogen levels in the tailings. In conclusion, utilizing amendments for fertilizing copper tailings demonstrates superior fertilizer retention characteristics while providing essential nutrients for ryegrass growth. This approach could prove economical and effective when used for mine ecological restoration purposes aimed at rehabilitating surrounding ecological environments. Graphical AbstractHighlights: Resource utilization of copper tailings; Ecological restoration in high-altitude mining areas; Green restoration and sustainable development. [ABSTRACT FROM AUTHOR]