Biotic indices

Biotic indices that are relatively simple and inexpensive to apply can be very useful for identifying environmental problems caused by pollutants. Serious effects of pollutants can cause departures from normal profiles. The problem is, however, identifying which pollutants—or which other enviromnental factors—are responsible for significant departures from normality. This dilemma illustrates well the importance of having both a top-down and a bottom-up approach to pollution problems in the field. Chemical analysis and biomarker assays can be used to identify chemicals responsible for adverse changes in communities detected by the use of biotic indices. 

Important in trophic transfer of MeHg To select biotic indicators with a significant role in the trophic transfer of MeHg in aquatic food webs Unclear Important Highly important Highly important Highly important Highly important... 

Also, a sediment quality system has been developed that combines chemical analyses with biotic indices in the so-called TRIAD (Sediment Quality Triad-integrated assessments of sediment quality based on measures of chemistry, toxicity, and benthos).112... 

Distribution Close to 500 species are represented in North America. Many stoneflies are known as clean-water insects, since they are often restricted to highly oxygenated water. As such, some are excellent biotic indicators of water quality. Adults of stoneflies can be found throughout the year, some being adapted for winter emergence. (Aquatic Entomology, 148). 

Chemical guideline(s) exceeded Biotic indices impaired Toxicity (field or lab.) Tissue residues elevated Habitat impairment ... 

In the last years different other biotic indices have been designed to assess the ecological quality of coastal waters. The development of biological indicators as a tool for the assessment and hence protection of biological diversity in European coastal and marine ecosystems has been advanced due to the implementation of the Habitats Directive and the Water Framework Directive (WFD). 

Grail, J., Glemarec, M., 1997. Using biotic indices to estimate macrobenthic community pertubations in the Bay of Brest. Estuarine, Coastal and Shelf Science, 44 (Suppl. A), 43-53. 

FIGURE 17.39 Stepwise canonical discriminant analysis of biotic indicators measured along phosphorus gradient in WCA-2A. (From Corstanje et al., 2007.)... 

Resh, V.H., Myers, M.J. and Hannaford, M.J. (1996) Macroinvertebrates as biotic indicators of environmental quality. In Methods in Stream Ecology (eds F.R. Hauer and G.A. Lamberti), Academic Press, London, pp. 647-667. 

---