From Phytoremediation to Safe Land Reuse: A PRISMA-ScR Review and Decision-Support Framework for Non-Food Crops on Metal-Contaminated Mining Soils

Metal-contaminated mining soils require management options that reduce environmental risk while enabling the controlled reuse of degraded land. Following the PRISMA extension for Scoping Reviews (PRISMA-ScR), this review synthesizes evidence on the use of non-food crops for the phytomanagement of metal-contaminated mining soils, with particular emphasis on crop establishment, agronomic performance, metal uptake and partitioning, biomass safety, valorisation pathways, and safe land reuse. Searches conducted in Web of Science, Scopus, and ScienceDirect, complemented by Google Scholar and manual screening, identified 7223 records; after duplicate removal and eligibility assessment, 85 publications were included in the final synthesis. The evidence indicates that non-food crops can support phytostabilization, exclusion-based phytomanagement, biomass production, and, in selected cases, phytoextraction. However, their suitability is strongly site-specific and depends on substrate constraints, contaminant behaviour, biomass quality, and residue-management requirements. Field and pilot-scale evidence remains less frequent than pot and greenhouse studies, which limits the direct transfer of findings to heterogeneous post-mining landscapes. Biomass safety emerged as a critical decision point because harvested biomass and conversion residues may become secondary contamination pathways. Based on the evidence map, this review proposes a seven-step conceptual decision-support framework linking site diagnosis, management objective definition, crop pre-selection and field-performance screening, metal-risk behaviour assessment, biomass safety assessment, land-reuse matching, and adaptive monitoring. The proposed framework is intended as a screening and planning tool and requires site-specific validation before operational implementation.