EFFECTS OF THERMAL ALTERATION 

 ON MACROINVERTEBRATE FAUNA 

 IN THREE ARTIFICIAL CHANNELS 



DALLAS E. ALSTON, J. M. LAWRENCE, DAVID R. BAYNE, and 

 FRANCES F. CAMPBELL 



Department of Fisheries and Allied Aquacultures, Agricultural Experiment 

 Station, Auburn University, Auburn, Alabama 



ABSTRACT 



Three earthen channels constructed at the Greene County Steam-Electric 

 Generating Plant in Alabama were used in a 2-year study to evaluate the effects 

 of heated effluents on aquatic biota. Macroinvertebrates were collected with 

 modified Hester— Dendy multiple-plate samplers and an Ekman dredge at 4- to 

 6-week intervals throughout the period. Channel 1, a control habitat, received 

 unheated river water; channel 2, a thermally stratified habitat, received both 

 unheated water and heated effluent waters from the steam plant; and channel 3 

 received only heated water. The highest average weekly water temperature in 

 channel 1 was 30.8°C and in channel 3, 35.5°C. During most periods 

 oligochaetes and chironomid larvae (Diptera) were the dominant organisms 

 found in both plate and dredge samples. Total fish-food organisms collected 

 from plate and dredge samples were in channel 1, 132,000, and in channels 2 

 and 3, 160,000. The overall mean diversities for dredge samples indicated that 

 channels 1 and 2 were not significantly different, but channel 3 had a lower 

 diversity. The plate samplers indicated that channel 1 had the highest diversity; 

 channel 2, intermediate; and channel 3, lowest. Channels 1 and 2 had more 

 mayflies (Ephemeroptera) than did channel 3. 



Much work has been done to determine the effects of thermal 

 alteration on aquatic ecosystems (Federal Water Pollution Control 

 Administration, 1967; Raney and Menzel, 1969; Coutant and 

 Goodyear, 1972; Coutant and Pfuderer, 1973; 1974; Coutant and 

 Talmage, 1975; Gibbons and Sharitz, 1974; Esch and McFarlane, 

 1976; Lehmann, 1976). Some of these studies were conducted in the 

 vicinity of heated-water effluents with little or no control over 



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