The objective of this study was to develop a simple and user-friendly model and to examine the Cd-phytoextraction of Ornamental Kale (Brassica oleracea var. viridis). For this purpose, a new formulation was established based on soil and plant responses to Cd pollutants. This proposed model assumes that relative transpiration reduction function can resemble total soil Cd concentration. Combining the related functions of soil and plant responses to soil Cd concentrations, the phytoexteraction rate of Cd was predicted. To test the models, large quantities of soil were thoroughly polluted with Cd. When soil and pollutant equilibrium was reached, the contaminated soils were carefully packed into the pots. Ornamental Kale seeds were then germinated in these pots. The proposed model was tested against the experimental data. The results indicated that the transpiration reduction function followed a non-linear trend. Also, the results indicated that the proposed macroscopic model can reasonably well predict the Cd-phytoexteraction (R2>0.92).
