Sustainable approaches to tailings remediation: Role of organic fertilizers

Tailings, a by-product of mineral processing, challenge environmental restoration due to poor structure, low nutrients, and ecological risks. This study employs bibliometric methods to systematically summarize the classification, detrimental effects, and restoration technologies associated with tailings, with a particular focus on the regulatory mechanisms of organic fertilizers in tailings restoration. The aim is to provide a scientific foundation for the ecological restoration and resource utilization of tailings, thereby promoting the sustainable development of mining practices. The findings indicate tailings can be classified into various categories based on the ore dressing process and petrochemical characteristics. Tailings remediation technologies primarily consist of physical, chemical, biological, and phytoremediation methods. Research indicates that organic fertilizers can markedly enhance the physical properties of tailings by reducing bulk density, increasing porosity and water retention capacity, promoting the formation of aggregates, and improving soil structural stability. Additionally, organic fertilizers can help regulate the pH of tailings towards neutrality and decrease the bioavailability of heavy metals through mechanisms such as adsorption, complexation, and precipitation. In addition, organic fertilizers can stimulate microbial activity, promote plant growth, and enhance the recovery capacity of tailings ecosystems. Existing studies have limitations:they lack tailored repair strategies and organic fertilizer selection criteria for different tailings characteristics, have insufficient long-term research on biological activity, and face potential issues of heavy metal accumulation and ion balance from organic fertilizer use. Future research should prioritize the development of customized repair strategies for various tailings types; strengthen long-term monitoring of agglomerate stability and microbial community dynamics; evaluate the sustainability of repair effects; explore the synergy between organic fertilizers and other modified agents; and develop targeted regulatory technologies for multi-material coupling. Furthermore, integrating genetic engineering and plant breeding technologies can enhance plants' tolerance and enrichment capabilities concerning heavy metals, thereby promoting the ecological and resource-based development of tailings repair.