Research progress on environmental impacts of iron tailings and prevention strategies

The large-scale stockpiling and improper disposal of iron tailings have become a key issue restricting the sustainable development of the global mining industry. Their long-term open-air storage not only occupies a large amount of land resources, but also leads to the diffusion of heavy metal elements into the environment through leaching, wind erosion and other pathways, causing cross-media and cross-regional complex pollution and triggering a series of severe ecological problems such as water eutrophication, soil degradation and loss of biodiversity, posing multi-level and multi-scale environmental risks to ecosystem health and human living environment. Typical iron tailings ponds in many parts of the world are taken as the research object and the pollution characteristics and environmental behavior of iron tailings are systematically analyzed. Firstly, it comprehensively reviews the pollution mechanisms of iron tailings on surrounding water bodies, atmosphere, soil and ecosystems, revealing the migration and transformation laws of heavy metals and their ecotoxicological effects. On this basis, the research progress of current iron tailings pollution prevention and ecological restoration strategies are deeply explored, mainly including the following aspects. In terms of source control, it achieves the reduction of pollutant generation and resource recycling by optimizing the beneficiation process and developing green mining technologies. In terms of resource utilization, it focuses on the high-value utilization of iron tailings in the fields of building materials, ceramic preparation, and soil conditioners. In terms of end-of-pipe remediation, the system summarizes a physico-chemicalbiological combined restoration technology, including substrate improvement-vegetation reconstruction-microbial synergy as a set of human-assisted ecological restoration measures. Based on the systematic review of pollution mechanism and prevention strategies of iron tailings, it proposes innovative concepts such as intelligent responsive restoration materials and integrated system of graded utilization and restoration, providing technical routes with both scientific value and application potential for promoting mine environmental management and iron tailings pollution control.