Rhizofiltration potential of Arundo donax for cadmium and zinc removal from contaminated wastewater

Abstract

The main aim of the presented work was to design and characterize the rhizofiltration system comprised of giant reed plants (Arundo donax L.), as species with phytoremediation potential, for the removal of cadmium as a toxic metal and zinc as an important microelement from model solutions spiked with radionuclides 109 Cd and 65 Zn. The possibility of effective cadmium and zinc rhizofiltration by the root system of giant reed plants under continuous flow conditions to achieve complete decontamination was confirmed. The highest 109 Cd and 65 Zn specific radioactivity (Bq g −1 ; dry mass) was found in case of plants located near the input of the solution into the system, whereby the radioactivity in the plants decreased in the direction of the solution flow within the system. On the other hand, gradual increasing of the concentration ratio [Cd] shoot : [Cd]root within this horizontal plants location was observed. Individual experiments showed that the efficiency of cadmium rhizofiltration decreased in the order of model solutions: synthetic wastewater (χ = 505 µS cm −1 ), deionized water (χ = 29.6 µS cm −1 ), 100 % Hoagland medium (χ = 1675 µS cm −1 ). The same results were also found in case of zinc rhizofiltration. For the description of cadmium and zinc rhizofiltration processes, the kinetic mathematical models widely applied for sorption processes under continuous flow conditions were successfully used.

Phytoremediation of Cadmium: Physiological, Biochemical, and Molecular Mechanisms

“…Islam et al [95] reported the phytofiltration capability of Micranthemum umbrosum to remove Cd and arsenic (As) from a hydroponic system. In another experiment, the rhizofiltration potential of Arunda donax for Zn and Cd removal, it and recommended the use of the rhizofilteration technique for Cd elimination [96].…”

A Review of Plant Bioindicators in Wetlands

“…Overall, the genus Phragmites is one of the most effective plants in removing pollutants from wetlands [46]. For the other plant bioindicators, the literature review revealed metals to be assimilating in shoots and roots of Aruno donax and Nasturtium officinale indicating their strong phytoremediation potential [47,48]. Although some studies observed Nasturtium officinale to have a threshold for uptake of metals such as Pb, Cd and As [49].…”

Application of phytoremediation for heavy metal contaminated sites in the South Pacific: strategies, current challenges and future prospects

“…In contrast, rhizofiltration primarily employs the roots of certain terrestrial or aquatic plant species to absorb, concentrate, and precipitate HMs from contaminated water and aqueous waste sources. By using rhizofiltration, numerous plant species have been found to effectively remove HMs such as Pb, Cd, Cu, Ni, Zn, and Cr, which are primarily held within the roots and has been proven to be suitable for the treatment of acid mine drainage, partially treated industrial discharges and agricultural runoff, as well as low-level radioactive contaminants from liquid streams [12].…”