Potential Heavy Metals Accumulation of Indigenous Plant Species along the Mafic and Ultramafic Terrain in the Mohmand Agency, Pakistan

Abstract

This study investigates the heavy metals concentration in soils derived from mafic and ultramafic rocks of the Kot Parang Ghar mélange zone in the Bucha Area, Mohmand Agency, Pakistan. Furthermore, plant species grown on these soils are assessed for their bioaccumulation ability. Representative samples (soil and plants) were collected and analyzed for heavy metals concentration using atomic absorption spectrophotometer. Heavy metals concentration in the serpentine soil were significantly higher ( p < 0.01) than the background soil values. Correlations between plant metal uptake and soil total metal were highly diverse due to different accumulation potential of plant species growing in the habitat. Among the selected plant species, Lycopersicon esculentum and Chrysopogon zizanioides showed manifold higher concentrations of iron, manganese, nickel and chromium and hence capable to uptake and translocate these metals in their tissues to a greater extent. Based on these observations, the local plant species could cause environmental impact in the study area as chromium and nickel contaminations have toxicological concerns. These plants can also be used as bioindicators for exploration of chromite ores.