Cr (III) and Cr (VI) absorption and translocation of Atriplex halimus L.

Abstract

Metal pollution has become, due to industrial and technological advances in recent decades, a major threat to human health and environment. It is thus important to have effective tools to assess the bioavailability of metallic element and their environmental effects in contaminated soils. The purpose of the present work was to evaluate the tolerance and capacity to accumulate chromium in its two valence states, Cr(III) and Cr(VI) of Atriplex halimus L., grazing species, one of the most abundant perennial halophytes which is found as hedges in agricultural soils near a discharge of a bolts, cutlery and fittings factory (BCR, located in Oued Rhiou, Algeria). The soil taken from the discharge of the BCR factory is used in the experiment. The obtained results show a variation of the accumulation of chromium according to the plant organs, the metal form and the rate of chromium. Chemical tests reveal an evolution of the chromium content in the aerial parts (leaves and stems) and the ground organs (roots) of Atriplex halimus L. This variation is related to the increase in dose and type of the used chromium. It was also found that Cr-III is more absorbed by Atriplex halimus L. than Cr-VI. The growth parameter results also show that Atriplex halimus L. is more tolerant to trivalent chromium than to hexavalent chromium. We finally found that this species present a large absorption roots capacity and a low translocation to the above ground organs.