Bioassessment

According to the official definition of the United States Environmental Protection Agency (EPA), bioassessment refers to the process of evaluating the biological condition of a body of water using biological surveys (biosurveys) and other direct measurements of the resident biota—those organisms living in the surface water, including fish, insects, algae, plants and others. Since 1972 when the Clean Water Act was passed by Congress in order to clean up America's polluted waterways, the biological integrity of the nation's bodies of water has been the focus of professionals and citizens in ensuring the success of reaching this goal.

The derivation of biocriteria emerges from the bioassessment, and offers a narrative or numeric expression that explains the life surviving in the water. The process of evaluating biocriteria can be in "scores" using a method known as the Ohio multimetric approach; or, reported in "clusters" according to the Maine statistical approach.

Particularly in the study of water pollution , and the examinination of ways to correct it, a bioassessment of a body of water measures the composition, diversity, and functional organization of the community living in it. Consequently it lays the groundwork for the biocriteria in the determination of the quality of the desired goal in regard to the condition of the resource, and to what maximum level of management that water can be maintained. The result is not how extensive the pollutant level can be. The result of any bioassessment should be that the unique members of this community of living organisms thrive as they interact with the various elements of their common home. Biocriteria must be maintained separately from any chemical evaluation, whose whole effluent toxicity (WET) is a distinct measurement, and plays a different role in water management, along with the physical and toxicity factors also included in a complete water quality management program.

Measuring biological integrity is accomplished most successfully when researchers utilize the Rapid Bioassessment Protocols (RBPs) established originally in the 1980s by the EPA, and revised and reissued in 1999. The concept at the core of these protocols according to the official EPA information are:

• Cost-effective, scientifically valid procedures for biological surveys
• Provisions for multiple site investigations in a field season
• Quick turn-around of results for management decisions
• Scientific reports easily translated to management and the public

These RBPs resulted from those methods already in use by several state agencies. They are useful in the following areas of study:

• Determining if a stream is supporting a designated aquatic life use specified in state water quality standards
• Characterizing the existence and severity of impppairment to the water resource
• Helping to identify the sources and causes of impairment
• Evaluating the effectiveness of control actions and restoration activities
• Supporting use attainability studies an cumulative impact assessment
• Characterizing regional biotic attributes of reference conditions.

Not only are current living conditions key factors in studying this aquatic life. Physical and biological elements known as stressors are those that exert a negative or adverse effect on the organisms. How those stressors might have affected the organisms over a long period of time is crucial to understanding what actions will be necessary to improve the ecology of the waterbody.

Centers and groups for bioassessment are active in each state throughout the United States, and throughout the world. They operate with scientifical professionals such as biologists, as well as include trained citizen groups who participate by volunteering their time to monitor local water conditions. In one such program begun in California in 1998, trained citizen groups throughout the state under the training and guidance of a water biologist with the California Department of Fish and Game (CDFG) track the abundance and diversity of macroinvertebrates in order to assess the effects of pollution . This method was considered one of the best ways to monitor the health of streams and lakes due to the fact that each species is adapted to thrive in a particular habitat—along with an examination of bugs, whose various reactions to different types of pollutions have been monitored and well-established for years.

In an article written for the EPA Journal, in 1990, "Measuring Environmental Success," Steve Glomb noted that, "Biological community interactions are probably the most difficult goals to measure, Many scientists, however, think that these interactions are the most important factors to assess." Those interactions are often subtle, such as the example of invertebrates living in the mud on the floor of coastal waters, as Glomb mentioned. "Because they don't move much," he observed, "they can be used as an indication of problems over time." In determining past and current living conditions, bioassessment has proved an invaluable tool in implementing the goals of clean water for all life, including humans.

[Jane E. Spear ]

RESOURCES

PERIODICALS

California Aquatic Bioassessment Workgroup. Mission Statement &lt: http://www.dfg.ca.gov/>

Central Plains Center for BioAssessment. Home Page. http://www.cpcb.ukans.edu/>

Glomb, Steve. "Measuring Environmental Success." EPA Journal 16 (Nov/Dec 1990): 57.

Levy, Sharon. "Using Bugs to Bust Polluters." Bioscience 48 (May 1998): 342.

U.S. Environmental Protection Agency. Biocriterial. http://www.epa.gov/ost/>

Yosemite National Park/U.S. Environmental Protection Agency. Water. http://www.yosemite.epa.gov/>

ORGANIZATIONS

California Aquatic Bioassessment Workgroup, Department of Fish and Game, 1416 Ninth Street, Sacramento, CA United States 95814 (916)445-0411, Fax: (916)653-1856, <www.dfg.ca.gov>

Central Plains Center for BioAssessment, 2021 Constant Avenue, Lawrence, KA United States 66047-3729 (785)864-7729, Email: dbaker@ukans.edu, <www.cpcb.ukans.edu>

U. S. Environmental Protection Agency, 1200 Pennsylvania Avenue, NW, Washington, D.C. United States 20460 (202) 260-2090, , <www.epa.gov>