Microbial eco-physiological indicators to asses soil quality

The demand for quick and reproducible soil quality indicators in order to detect soil quality changes have increased over the last decade. Since soil functioning and sustaining soil fertility is governed largely by the decomposition activity of the microflora, there is particularly a need for microbial-based indicators. This short overview presents concepts and recent discussions found in the pertaining literature about the microbial biodiversity aspect of taxonomic species diversity in relation to environmental impact and taxonomic species diversity in relation to soil functioning, both of which seem at present inadequate for use as indicators. It also introduces the potential of ecological theory at the microbial community level and its use for indicator development. Here, own experiences on eco-physiological indicators are presented and their possible use for establishing eco-physiological profiles of soil sites are proposed. (C) 2003 Elsevier Science B.V. All rights reserved.