Rotifera composition and vertical distribution in Aslantas Dam Lake was studied from April 2001 to March 2002. It was established that the rotifera were represented by 33 species and 2 subspecies in the lake. Total average density of the rotifera was found to be 255883 Rotifer/m 3 . Species such as Keratella cochlearis cochlearis, K. cochlearis tecta, Polyarthra dolichoptera, Trichocerca capucina and Asplanchna priodonta were present througout the year. The analysis for the determination of

more »

... ical distribution of Rotifera showed that the most abundant species at surface and below surface was P. dolichoptera with 34.59%, and K. cochlearis cochlearis with 29.29%, respectively. Rotifera had the highest density at 5 m in the lake. In addition, 63.58% of total Rotifera was observed in photic zone while the rest (36.42%) was collected from aphotic zone. Chlorophyll a measurement of the dam lake showed that the average montly values were 31.44 mg/m 3 at the surface and 20.13 mg/m 3 below the surface. A vertical increase at the value of chlorophyll a was observed from the surface to 7.5 m. Gradual decrease at the value was recorded exceeding the depth of 7.5 m.