Microbial community-based measurements to estimate heavy metal effects in soil : The use of phospholipid fatty acid patterns and bacterial community tolerance

Microbial community-based measurements to detect effects of heavy metals in soils rely on the premise that metal toxicity exerts a selection pressure, which induces a change in the composition of the community. The phospholipid fatty acid (PLFA) composition gives an integrated picture of all living organisms in the soil, and changes in the PLFA pattern of the soil indicate an altered species composition due to, e.g. metal toxicity. An increased bacterial community tolerance to metals also indicates an altered community composition, with tolerant organisms becoming more abundant relative to sensitive organisms. The use of these two techniques is described, and their advantages and disadvantages as monitoring tools are discussed and exemplified by field data and laboratory experiments from different soils