Key Concepts for Using Biological Indicators
EPA has developed draft guidelines intended to describe the technical attributes and processes of State and Tribal biological assessment programs. Increasingly, biological assessments and criteria are being used and formalized in State and Tribal programs to refine designated aquatic life uses and improve the identification of impaired waters. With this, the need to recognize and communicate technically sound approaches takes on increasing importance and urgency. In addition, it is essential to provide detailed guidelines and milestones by which States, Tribes, and USEPA can evaluate progress when developing and improving biological assessment programs.
The quality and level of rigor of a bioassessment program is dependent upon the quality and level of resolution of each of its technical elements, which are categorized as 1) survey design (the extent of temporal {index period} and spatial coverage, natural classification, characterization of reference conditions, and reference site criteria), 2) methodology (number of assemblages, field sampling, sample processing, and management of the data), and 3) quality of the interpretation (ecological attributes, biological endpoints, diagnostic capability, and professional peer review). Certain aspects of monitoring and assessment, particularly quality assurance/quality control (QA/QC), are inherent in several technical elements of a viable bioassessment approach. An explanation of the key attributes of each element is presented in the following links.
- Data Quality Objectives (DQOs)
- Meausrement Quality Objectives (MQOs)
Key Technical Elements
Design
1. Index period
2. Spatial coverage
3. Natural classification
4. Criteria for reference sites
5. Reference conditions
Methods
6. Taxonomic Resolution
7. Sample collection
8. Sample processing
9. Data management
Interpretation
10. Ecological attributes
11. Biological endpoints
12. Diagnostic capability
13. Professional review
For additional information on many of the topics, please visit
- Developing Biological Indicators: Lessons Learned from Mid-Atlantic Streams and Lessons Learned for Bioassessment.
- Multimetric Indices to Prepare and Analyze Data
- Obtain Water Quality Score Results
- Present Results for Decision-Making