RESEARCH IN ARTIFICIAL STREAMS - APPLICATIONS, USES, AND ABUSES

Increased use of artificial streams in aquatic research over the last 20 years has not been accompanied by a systematic, critical analysis o f their advantages and disadvantages. A symposium held at the 1992 ann ual meeting of the North American Benthological Society in Louisville, Kentucky, attempted specifically to provide this information. We defi ne an artificial stream as any constructed channel that has a controll ed flow of water and that is used to study a physical, chemical, or bi ological property of natural streams. The following aspects of artific ial streams were covered in the symposium: historical perspectives, hy drodynamics, algal-nutrient dynamics, macroinvertebrate growth, grazer -algal interactions, fish ecology, disturbance, ecotoxicology, small- and large-scale artificial streams, and longitudinal linkages. Althoug h the symposium addressed a wide variety of subjects, each contributio n was linked by a common desire to ascertain the strengths and weaknes ses of artificial streams relative to that subject. Major conclusions that emerged from the symposium include; (1) there is no single best d esign for artificial streams; appropriate stream design is contingent on the question being asked; (2) research geared to mechanistic unders tanding of lotic processes is particularly well-suited for artificial streams; and (3) generation of testable hypotheses, which can then be validated in natural stream ecosystems, is a useful application of res earch in artificial streams.