However, distinctly different

environmental conditions might require such different selleck screening library physiological or ecological adaptation strategies that tolerance ranges might become exceeded not only for species, but also for aggregated taxonomic groups. Indeed, studies pertaining to sites that are distinctly different with respect to for example land use or the degree of human CYT387 disturbance showed that relatively coarse taxonomic arthropod data were sufficient to discriminate between the sites, despite a relatively large degree of taxonomic bifurcation (Biaggini et al. 2007; Nakamura et al. 2007). The lowland floodplains along the Rhine river in The Netherlands are characterized by considerable environmental heterogeneity, due to both natural processes and human influences (Schipper et al. 2008a). On a small spatial scale, relatively large differences

can be found with respect to e.g., elevation, flooding, soil characteristics, and vegetation types. Such a wide range of environmental conditions might require such different physiological or ecological adaptations that arthropod assemblages show clear spatial variation not only at low, but also at higher taxonomic levels. This likely explains why indicator taxa for a distinct vegetation type like the hedgerow were found not only among the ground beetles and beetles, but even among the rather coarse arthropod groups at class–order level. In addition to the degree of taxonomic bifurcation and the degree of environmental heterogeneity, differences Saracatinib solubility dmso in research goals might explain why the Tideglusib literature is inconclusive concerning the taxonomic level most suited for biological monitoring. If a study aims to detect the influence of perturbations or distinct environmental characteristics on organism distribution, identification to family or maybe even order level can be sufficient. However, if the goal is to detect small between-site differences in environmental

characteristics and to provide an interpretation of the ecological consequences, it might be necessary to perform identification at lower taxonomic levels (Basset et al. 2004; Lenat and Resh 2001). The lower the taxonomic level, the more specific and thus informative a taxon’s distribution becomes (Williams and Gaston 1994). Indeed, the ground beetle family as a whole (Carabidae) was no significant indicator for any of the vegetation types, whereas ten of the species within this family were significant indicators for four different vegetation types (Table 4). The higher specificity of taxa at lower taxonomic levels may also explain why the ground beetle genera and species showed a significant relation to soil heavy metal contamination, whereas no significant relations with soil contamination could be detected for the beetle families and the arthropod groups (Table 3). Summarizing, the question concerning the most appropriate taxonomic level for biological monitoring cannot be answered by rigidly recommending one level of taxonomy (Lenat and Resh 2001).