Correlation of Extractable Metals and Metal Uptake of Snap Beans Grown on Soil Amended with Sewage Sludge

A field study was conducted in which anaerobically digested sludge was applied to sandy Udorthentic Haploboroll soil as single applications (0, 112, 225, and 450 metric tons/ha) or as three annual sludge applications (accumulated total 0, 350, 700, and 1,400 metric tons/ha). In both cases sludge‐borne trace metals removed by several chemical extractants were correlated to trace metal uptake by snap beans ( Phaseolus vulgaria L., Cv. Tendergreen) and soil organic matter. A highly significant linear correlation was found between: (i) DTPA‐, KNO 3 ‐, Na 4 P 2 O 7 ‐, and NH 4 C 2 H 3 O 2 ‐extractable Zn and Zn concentrations in edible bean tissue, bean leaf tissue, and organic matter; (ii) DTPA‐, Na 4 P 2 O 7 ‐, and NH 4 C 2 H 3 O 2 ‐extractable Cu and Cd and their concentrations in edible bean tissue and organic matter; (iii) DTPA‐, Na 4 P 2 O 7 ‐, and NH 4 C 2 H 3 O 2 ‐extractable Ni and Pb and organic matter; and (iv) Na 4 P 2 O 7 ‐extractable Cr and organic matter. Pyrophosphate extracted the highest percent of applied metal, except for Ni where the Na 4 P 2 O 7 and DTPA extracted approximately equal quantities. Except for Cr, a highly significant correlation was observed between Na 4 P 2 O 7 and DTPA or NH 4 C 2 H 3 O 2 ‐extractable metal. A highly significant linear correlation was found for the 4‐year period between DTPA‐extractable Zn and Cu and their concentrations in edible bean tissue, bean leaf tissue, and organic matter. For the single application series the maximum percentage of applied Zn and Cu was extracted during the second year.