Harnessing the potential of invasive plants biomass for biochar production and coal-mine spoil reclamation: A review

The coal mining industry plays a vital role in driving economic growth. However, mining activities generate vast amounts of coal mine spoil, leading to severe environmental degradation. It contains acidic pH, high bulk density, and toxic contaminants, which hinder plant growth. Biochar derived from invasive plant biomass can significantly improve soil properties, including bulk density, water-holding capacity, and the immobilization of contaminants, while also promoting plant growth. Compared to conventionally used biomass, biochar derived from invasive plants exhibits distinct physicochemical properties and contaminant adsorption capacity. Its utilization provides the dual advantage of managing invasive plants and restoring degraded mine land. Research on invasive plant-based biochar is primarily confined to laboratory studies, whereas its application in coal mine spoil reclamation remains underexplored. Moreover, reviews specifically addressing this topic remain scarce, highlighting a critical gap in the existing literature. Therefore, this review critically evaluates the physicochemical properties of biochar derived from invasive plants and its potential for the reclamation of coal mine spoils.