COMMUNITY DNA HYBRIDIZATION AND PERCENT-G-METAL POLLUTED SOILS(C PROFILES OF MICROBIAL COMMUNITIES FROM HEAVY)

Microbial community DNA was extracted directly from an arable soil exp erimentally polluted with Cd, Cu, Ni, Pb or Zn, and incubated for 34 m onths. Broad-scale measurements of changes in microbial community stru cture were assessed by applying %G+C profiling and community hybridisa tion techniques to the DNA, and compared with phospholipid fatty acid (PLFA) profiles. %G+C profiles, statistically compared using parameter isation and principal component analysis, differed between treatments. Community hybridisation revealed a range of DNA similarities between treatments. The combination of these two techniques facilitated the in terpretation of the data. The differences between the treatments deter mined by DNA analysis were consistent with the PLFA patterns, and reve aled that: (i) microbial communities in metal contaminated soils were different from those in uncontaminated soil, (ii) the microbial commun ity in Cu contaminated soil was different from those in soils contamin ated with the other metals, and (iii) the microbial communities in soi ls contaminated with Pb and Ni were indistinguishable from one another .