Past and present status of nematode community indicators

Differences in sensitivity of nematodes towards some chemicals have been recognised for nearly four decades. Initially, single species or taxonomie groups were considered, followed by parameters of whole communities to measure different properties of natural and disturbed terrestrial ecosystems. A short overview of nematode community Indices is presented, progressing from those considered traditional, relatively simple, and widely applied in environmental studies (e.g., abundance, richness, diversity, similarity and constancy) to those considered more sophisticated (e.g., Maturity Index and its modifications) and specific to nematodes (e.g., proportions among trophic groups). The analysis of 76 case studies carried out in forests, grasslands, crops and mixed ecosystems showed that among the most commonly used Indices, total abundance and abundance of trophic groups were successful at differentiating nematode communities. In contrast to those Indices, number of taxa, and Shannon-Weaver Diversity Index seem less informative. Maturity Indices were better indicators for assessing changes in agroecosystems than in forests. Fundamental constraints and research priorities were identified, e.g., clarifying trophic affinity of some species, integrating morphological, ecological and molecular approaches, and intensifying long-term studies in natural and disturbed environments.