The invention relates to a treatment method of treating
cadmium contaminated water, and relates to a treatment method of
contaminated water. The treatment method comprises the following steps of: planting one or two of a
cadmium hyperaccumulator plant, namely nightshade, and leaf beta vulgarisvar.cicla into water to be treated; activating and absorbing
cadmium contained in the
contaminated water; continuously extracting the cadmium contained in the contaminated water by continuously and regularly collecting and replacing the plants till the cadmium content of the water achieves a safety standard; and culturing nightshade and leaf beta vulgarisvar.cicla plants: yielding the nightshade and leaf beta vulgarisvar.cicla plants through seed
germination and
greenhouse culture. One or two of the nightshade and the leaf beta vulgarisvar.cicla is or are planted in the water to be treated, and a planting method comprises the following steps of: planting the plants into a floating
bed, wherein roots directly contact with the contaminated water through small holes drilled on the floating
bed; and continuously and regularly collecting and replacing the plants, and collecting and replacing the plants for one time every 15-20 days till the cadmium content of a
water body achieves the safety standard. According to the invention, the two plants have the advantages of hyperaccumulation capacity on the cadmium,
root system upgrowth, vigorous growth, easiness for propagation and higher
biomass, so that the cadmium contaminated
water body is efficiently restored.