Paper Title
Mathematical Model of Heavy Metal Removal from Soils using Plants

Abstract
Heavy metal contamination of soil-water system is a ubiquitous problem and remediation of such polluted resources is required to eliminate the risk to human and the environment. Phytoextraction is an eco-friendly technology through which plants are used for removing heavy metal from polluted sites. The effective implementation of phytoextraction requires a conceptual insight of the soil-plant-atmosphere continuum process that controls the removal of metal pollutants from the problematic area. A mathematical model is developed to investigate the removal of a heavy metal, lead, by maize at different stages of it growth. The model comprises two parts; 1) moisture flow prediction and 2) contaminant uptake simulations. In the first part, the actual water uptake by plant is predicted and the hydraulic regime of the root zone for different moisture conditions is computed. Through the second part of the model, the extraction kinetics of lead is simulated using the data of water uptake and plant root biomass accumulation. The set of partial differential equations developed are solved numerically by the finite difference technique for varying boundary conditions. Keywords - Phytoextraction, Maize, Heavy metal, Mathematical model, Lead