Fig. 2. (a) Cadmium, (b) Zn, (c) Cu, (d) Pb, (e) As, (f) Bi, and (g) Tl distributions in sludge and soil samples. CL, clay loam; CLc, calcareous clay loam; Cs, saline clay; -h, highly contaminated soil; L, loam; -l, low-level contaminated soil; -r, noncontaminated reference soil; SLhy, hydromorphous sandy loam.