ABSTRACT
Mining activities result in heavy metal (HMs) pollution and pose threats to human health, reduce natural vegetation, and impose socioeconomic impacts on communities around mining sites. Remediation technologies like HM biosorption, biochar application, and phytomining have the goal of cleaning the environment. They are applied in the mining landscape for the adsorption and recover of HMs and for phytotoxicity reduction. Biosorption can help in the recovery of HMs from polluted soil, acid mine drainage systems, and wastewater. Biochar application can help in increasing soil pH, establishing vegetative cover, and reducing the runoff and erosion of mine waste (water- and air-suspended particles) areas far away from mines. Biochar can be used to assist in phytoremediation practices aimed at in situ stabilization and reducing the uptake and bioavailability of HMs in polluted soils. Phytomining can be applied to recover the precious metals in plant biomass after it is harvested from polluted sites. These processes are successful to some extent, but they also have specific limitations in the long run. Biosorbents have limited reuse efficiency for HM recovery. Biochar can also cause locking or oversupplying of soil nutrients, increases in soil pH, cementing effects, and changes in soil albedo. Phytomining is affected by the concentration of metals in the soil, plants, and plant biomass, but it offers the possibility of metals to be recovered and sold.
