Phytoremediation Potentials of Selected Plant Species at Nigerian Defence Academy (NDA) Shooting Range, Kaduna State, Nigeria

Abstract

Environmental contamination by heavy metals from industrial and military activities poses serious ecological and human health risks, particularly in shooting ranges where ammunition residues accumulate. This study assessed the phytoremediation potential and molecular characteristics of selected plant species at the Nigerian Defence Academy (NDA) shooting range. Soil and plant samples were collected from polluted and control sites, analyzed for heavy metals (Cd, Cr, Cu, Pb, Ni, Zn, Mn), and translocation factors (TF) were calculated.  Results indicated significant increases in Cu (67.65 ± 0.05 vs 26.55 ± 0.07 mg/kg), Cr (40.65 ± 2.05 vs 3.05 ± 2.05 mg/kg), Mg (111.50 ± 0.60 vs 54.60 ± 0.60 mg/kg), Ni (42.05 ± 0.85 vs 26.75 ± 0.85 mg/kg), Pd (21.700 ± 11.100 vs 33.400 ± 27.000) and Zn (46.55 ± 1.05 vs 21.45 ± 1.15 mg/kg) at polluted soils compared to controls, while Cd showed no significant difference. Among these plants, Chamaecrista rotondifolia exhibited high Cd and Zn accumulation with root-to-shoot TF > 1, indicating strong phytoextraction potential. Waltheria indica also exhibited high Cd and Zn accumulation with root-to-shoot TF > 1, indicating moderate phytoextraction potential. Furthermore, Aeschynomene uniflora demonstrated selective Pb, Cd, Zn, Mn, and Ni translocation, while Eriosema psoraleoides and Isoberlinia doka primarily exhibited phytostabilization traits. The findings highlight species-specific strategies in metal uptake, translocation, and stabilization. Future studies should include genomic analyses to identify metal tolerance genes in these promising species.