ABSTRACT
Sediments contaminated with nutrients, metals, organics and oxygen demanding substances can be found in freshwater and marine systems throughout the world. A number of approaches have been used to assess sediment contamination; however, they all employ either chemical or biological measures, or in some cases, both. The existence of a sustainable and reproducing biota is determined by the occurrence, through time, of an assemblage of species that is self-maintaining and resilient to environmental fluctuations. Four approaches to developing numerical guidelines for comparison of observed and expected communities are considered: a simple scoring system; percent difference in reference and test site means; calculation of X-values and; comparison in multivariate space. While in the example of the Detroit River, the people only include benthic invertebrate community structure data, this approach could easily be adapted to other biological data matrices. The Detroit River example is provided for illustrative purposes only.
