Phyto-management potential of naturally thriving plants on the metal contaminated overburden dump of coal mines: a study from Jharkhand, India

Abstract

Quality of land once disturbed due to mining either by opencast or underground mines though it cannot be fully restored back, it can be reclaimed by phyto-management. However, its success depends on the selection of the plant species based on their remediation ability. Here, an attempt was made to select native plant species which are dominant in a mining area of Kuju and Charhi, Jharkhand, India and have good metal accumulating capacity from coal mine overburden (OB) dumps. First, vegetation community study was performed to identify the dominant herb and shrub species through quadrat method. Seven dominant plant species were selected from the OB dumps and analyzed for metal uptake. Bioconcentration factor (BCF) and translocation factor (TF) of Cd, Ni, As, Fe, Pb, Mn, Zn and Se were calculated to understand the pattern of bioaccumulation and translocation into the various plant parts, respectively. Four plant species viz. Cynodon dactylon, Eulaliopsis binata, Croton oblongifolius, Lantana indica were found to be abundant in the area and efficient accumulators of metals from the soil. The order of uptake for the various metals in mg/kg of dry weight by the abundant plant species were Fe: 1191 > Mn: 441 > Zn: 232 > As: 12.5 > Ni: 10.91 > Pb: 8.6 > Se: 0.7 > Cd: 0.15. These species can thus be further utilized for phytoremediation of the degraded OB dumps and similar studies can help in other OB dump reclamation in other geographical and climatic regimes.