Microbial biomass and activity in lead-contaminated soil

Microbial community diversity, potential microbial activity, and metal resi stance were determined in three soils whose lead contents ranged from 0.000 39 to 48 mmol of Pb kg of soil(-1). Biomass levels were directly related to lead content. A molecular analysis of 16S rRNAs suggested that each soil c ontained a complex, diverse microbial community. A statistical analysis of the phospholipid fatty acids indicated that the community in the soil havin g the highest lead content was not related to the communities in the other soils. All of the soils contained active microbial populations that mineral ized [C-14]glucose. In all samples, 10 to 15% of the total culturable bacte ria were Ph resistant and had MIC of Ph for growth of 100 to 150 mu M.