Heavy metal bioaccumulation and distribution in Typha latifolia and Arundo donax: implication for phytoremediation

Abstract

In this study we determined the concentration of metals (Cd, Ni, Zn and Cu) in sediment and aquatic plants (Typha latifolia and Arundo donax). The level of pollution in the sediment was assessed using contamination factor (CF), pollution load index (PLI) and geo-accumulation index (Igeo). Obtained results have exhibited that the distribution of trace elements in sediment follows: Zn (196.51 µg g-1) > Ni (140.68 µg g-1) > Cu (121.56 µg g-1) > Cd (1.101 µg g-1). However, comparison of sediment metal concentrations with several environmental contamination parameters, such as: probable effect level (PEC) and background levels, indicated that the concentrations of all investigated elements were less than PEC, except that of Ni, albeit higher than the background levels. The Igeo values revealed that Cd (1.28 µg g-1) had been accumulated significantly in the Djendjen River. Contamination factor (CF) exhibited that the sedimentary samples were moderate in terms of all studied metal contaminations. The pollution load index (PLI) values were above one (>1), displaying an advanced decline of the sediment quality. In studied plants, results exhibited that the amount of concentrations in tissues is significantly dependent on the kind of organ and element. A. donax revealed a lesser capacity of bioaccumulation as well as a lesser efficiency of metal removal than T. latifolia. In contaminated aquatic ecosystems, the presence of T. latifolia may increase the removal of heavy metals, thus, their introduction contributed to a possible action of phytoremediation.