ML080280435

Biological Indicators of Watershed Health

ML080280435
Person / Time
Site:	Susquehanna
Issue date:	01/23/2008
From:	Environmental Protection Agency
To:	Office of Nuclear Reactor Regulation
References
TAC MD3021, TAC MD3022
Download: ML080280435 (2)

Text

EPA - Biological Response Signatures Page I of 2 http://www.epa.gov/bioindicators/html/brsig.html Last updated on Friday, November 30th, 2007.

Biological Indicators of Watershed Health You are here: EPA Home Biological Indicators of Watershed Health About Bioindicators Biological Response Signatures Biological Response Signatures For More Information:

Biological indicators are both accurate and sensitive measures of the health of waterways and they can also be used to diagnose sources and causes of pollution. Definite patterns exist in the responses of biological communities to stress (pollution), and finding these patterns can show what types of pollution are present, and sometimes the source of those problems. When the response patterns of the various metrics and components of IBIs (Indices of Biotic Integrity) are identified, these unique combinations of biological community characteristics that aid in distinguishing one impact type over another are referred to as "Biological Response Signatures."

Metrics When conducting biological assessments, measurements are taken in the field or lab.

Metrics (or biological attributes) for each assemblage sample (e.g., benthic invertebrates, fish, periphyton, macrophytes) are calculated from these measurements. The following table presents an example of representative metrics for each type of assemblage.

Biological Assemblage Benthic Macroinvertebrates Fish Metric No. of taxa ETO taxa (ephemeroptera, trichoptera, odonates)

% intolerant species

% suspension feeders No. of taxa

% piscivores No. of intolerant species No. of sunfish species No. of taxa

% dominant species (by weight)

No. of exotic species Species richness Pollution Tolerance Index for Diatoms Achnanthes minutissima Shannon Diversity (for diatoms)

Response to Stress Reduced Reduced under enrichment, DO, stress Reduced Reduced Reduced Reduced Reduced Reduced Low High High Not Determined Not Determined Not Determined Not Determined Macrophytes Periphyton Each metric is then assigned a score which is related to its deviation from the reference (or expected) site values. In more complicated studies, multimetric indices can be calculated, which is the sum of all the metric scores within each biological assemblage. <more on metrics>

For more information on biological response signatures:

Please see the discussions on the diagnostic value of biological 1/23/2008 http://www.epa.gov/bioindicators/htmlibrsig.html

EPA - Biological Response Signatures indicators in EPA's Stressor Identification Evaluation Manual and Ohio EPA's discussion on Biological Response Signatures (pdf file) and the Area of Degradation Value.

To learn more about metrics please visit the following sites:

Page 2 of 2 Reader to view some of the files on this page. See EPA's PDF page to learn more.

" The Rapid Bioassessment Protocols For Use in Streams and Rivers: Periphyton, Benthic, Macroinvertebrates, and Fish Protocols Chapter has a nice section on Metrics

• The Lake and Reservoir Bioassessment and Biocriteria Technical Guidance Document http://www.epa.gov/bioindicators/html/brsig.html 1/23/2008