HR: 13:30h
AN: NB13D-01 INVITED [Abstracts]
TI: Setting Expectations for the Ecological Condition of Streams:The Concept of Reference Condition
AU: Stoddard, J L
EM: Stoddard.John@epa.gov
AF: U.S. Environmental Protection Agency, 200 SW 35th St., Corvallis, OR 97333 United States
AU: * Larsen, D P
EM: Larsen.Phil@epa.gov
AF: U.S. Environmental Protection Agency, 200 SW 35th St., Corvallis, OR 97333 United States
AU: Hawkins, C P
EM: Chuck.Hawkins@usu.edu
AF: Department of Aquatic, Watershed, and Earth Resources, 5210 Old Main Hill
Utah State University, Logan, UT 84322 United States
AU: Johnson, R K
EM: Richard.Johnson@ma.slu.se
AF: Department of Environmental Assessment, P.O. Box 7050, Uppsala, Sweden
AU: Norris, R H
EM: Richard.Norris@canberra.edu.au
AF: Cooperative Research Centre for Freshwater Ecology, University of Canberra, Canberra 2601, Australia
AB:
One step in evaluating the current ecological condition of streams involves estimating the expected condition (or biological
composition) of the streams under study. The concept of a reference condition is increasingly used to describe the standard
or benchmark against which current condition is compared. Many individual nations, and the European Union as a whole, have
codified the concept of reference condition in legislation. However, the phrase "reference condition" has many meanings in a
variety of contexts. Our primary purpose is to bring some consistency to the use of the term. We argue that "Reference
Condition" should be reserved for referring to biotic integrity, defined in terms of the "naturalness" of the biota
(structure, composition, function, diversity) and that naturalness implies the absence of significant human disturbance or
alteration. To avoid the confusion that arises when alternative definitions of reference condition are used, we urge that
these specific terms be used to refer to the concepts and methods used in individual bioassessments: Minimally Disturbed
Condition; Historical Condition; Least Disturbed Condition; and Best Attainable Condition. We argue that each of these
concepts can be narrowly defined, and each implies specific methods for estimating expectations.
DE: 1845 Limnology
DE: 1871 Surface water quality
SC: North American Benthological Society [NB]
MN: 2005 Joint Assembly