Spatial distribution and population dynamics of a benthic rotifer, Embata laticeps (Murray) (Rotifera, Bdelloidea) in the bed sediments of a gravel brook

摘要: SUMMARY 1  The spatial and temporal distributions of the most abundant bdelloid rotifer, Embata laticeps (Murray), inhabiting sediment surface hyporheic interstitial a gravel stream were investigated between October 1991 1992. Three peaks population density occurred during year at differing in their riming from detected within bed sediments. 2  The depth E. pool riffle areas differed significantly. Higher abundances found 10 20 cm 30 area. In these two sites significant effect discharge (estimated 1 week before sampling) on rotifer densities was found. Discharge greater than 0.424 m3s−1 significantly reduced riffle, while only values 1.660m3s−1 influenced area. 3  The percentages egg-bearing females higher layer, area riffle. Thus, overall mean increase habitat (x= 0.015 ± SE 0.029 day−1) 0.004 0.025 0.005 0.026 day−1, respectively). addition, growth fluctuated more strongly intersiritial. Comparison observed with randomization test, where randomly permuted, revealed no differences those random model. clear trend over time could not be demonstrated this stream.