Comparative Evaluation of Metal Phytoremediation Potential of Trees, Grasses, and Flowering Plants from Tannery-Wastewater-Contaminated Soil in Relation with Physicochemical Properties

Abstract

This study reports a comparative account of metal accumulation in the trees, grasses, and flowering plants from agricultural fields contaminated with tannery wastewater. Soil physico-chemical properties along the pollution gradient and soil depth were analyzed. Monitoring and assessment of the plants growing on contaminated sites revealed that the accumulation of Cr in the aboveground part of the trees ranged from 1.87 to 34.44 μg g−1 dw with maximum concentration in Dendro-calamus strictus (34.44 μg g−1 dw). Chrysanthemum coronarium and Tagetes erecta showed better accumulation of Cr than other flowering plants. Separate field experiments were conducted on the contaminated area. The shoots of Vetiveria zizanoides (532 mg 4 m−2) and Cymbopogan winterianus (535.46 mg 4 m−2) have shown almost similar removal potential of Cr, with maximum removal potential in the roots of C. winterianus (1206.43 mg 4 m−2). Seasonal flowering plants (i.e., C. coronarium) have shown better accumulation of Cr than T. erecta. The results indicate that the plants of V. zizanoides, C. coronarium, and C. winterianus are suitable for phytoremediation of contaminated sites and trees can successfully be used for phytostabilization.