Taxocenes of Ephemeroptera in Unpolluted and Polluted Streams of the Tatra Mountains

Abstract

In the streams of the Tatra Mountains over 1550 m a. s. l. mayflies are generally lacking. At 900 to 1550 m a. s. l Baetis alpinus and Rhithrogena loyolaea dominate in the current, and Ameletus inopinatus in the pools. In the submontane zone of the streams (below 900 m a. s. l.) many other species appear. In a polluted stream (138U to 1390 m a. s. l.) below the outlet of sewage mayflies are absent. Thirty m below the sewage outlet B. vernus dominates from July to September (tourist season). One hundred to 500 m below the sewage outlet B. rhodani and B. muticus dominate. Single specimens of B. alpinus are also encountered but representatives of Rhithrogena are missing.