Fig. 3. Plant Root Simulator (PRS) chelating ion-exchange membrane Zn uptake in Blackwell smelter and Taloka reference soils receiving remediation amendments. Columns (mean, n = 4, ±95% CI) with the same letter are not significantly different (Fisher's protected LSD, P > 0.05); symbols indicate soil–amendment combinations lethal to the earthworm Eisenia fetida.