Fig. 4. Denaturing gradient gel electrophoresis (DGGE) profiles of PCR-amplified 16S rDNA fragments from tailings treatment plots 5 mo after transplants were established. Labels on top of the gel indicate the sample identity: C, compost plot; NC, no compost plot; U, unplanted control; M, marker ladder composed of heterotrophic mine tailings isolates; and N, negative control.