Availability of heavy metals for uptake by Salix viminalis on a moderately contaminated dredged sediment disposal site

Extractability of Cd, Cr, Cu, Ni, Pb, and Zn in a dredged sediment disposal site was assessed using single extraction procedures (H2O; 0.01 M CaCl2; 1 M NH4OAc; NH4OAc-EDTA; CaCl2-TEA-DTPA). Only Cd and Zn were found to exceed statutory threshold values for total content. The field was planted with Salix viminalis 'Orm' and accumulation of heavy metals in bark, leaves, roots, and wood was evaluated at seven sampling locations along an observed gradient in texture and pollution. Biomass production was high, ranging from 13.2 to 17.8 t ha-1 y-1 dry weight. Metal accumulation in aboveground plant parts was low, amounting to the following annually extracted mass of metals per ha: 5034 g Zn, 83 g Cd, 145 g Cu, 83 g Pb, 12 g Ni and 6 g Cr. The use of accumulating clones and the use of soil amendments might enhance extraction efficiency in future research. - Combination of energy cropping and phytoremediation with Salix sp. allows for economic revalorization of contaminated sites during the remediation process