Is phytoextraction a suitable green treatment for metal contaminated sediments?

Abstract

How to cite this paper: HUGUET S., SARRET G., BERT V., ISAURE M.-P., PROUX O., FLANK A.-M., HAMMADE V., BULTEEL D., LABOUDIGUE A. (2010 Abstract:The cleaning of waterways by regular dredging generates great volumes of sediments and, owing to human activities, these sediments often contain large amounts of metals. For some of these contaminated sediments, a treatment by phytoextraction could be considered. To our knowledge, phytoextraction with hyperaccumulating plants has been rarely tested on heavily contaminated sediments. This work consisted in a preliminary study of Cd phytoextraction potentialities and focused on the fate of Cd present in a metal-polluted dredged sediment during the culture of Arabidopsis halleri, a Zn and Cd hyperaccumulating plant. In this purpose, a five month pot experiment was achieved; results obtained for the first four months of monitoring are presented here. Cd contents in the sediment, in the aerial parts of plant and in the leachates were measured each month. Cd speciation in the sediment was studied by EXAFS and µXANES spectroscopy, Cd localization by SEM-EDX and µXRF. Before culture, Cd was present as mixed Zn, Cd and Fe sulphide in the sediment. Paralia -Vol. 3 (2010) During growth, plants were able to develop on sediment and accumulated about 100 mg Cd kg -1 in their aerial part from the first month of growth. The presence of plants decreased the amount of leached Cd. First results showed that culture of A. halleri on metal-contaminated sediments met some of the key objectives of Cd phytoextraction. UNE VERSION TRADUITE EN FRANCAIS EST DIPONIBLE EN LIGNE : Revue