DEVELOPMENT OF SUBMERGED MACROPHYTES IN THE TREATED SEWAGE CHANNEL WUHLE (BERLIN, GERMANY)

The environmental conditions for submerged macrophytes in sewage chann els ale different to those of natural waters. Mainly 6 eutraphent spec ies occur in two communities on the flowing stretch of the Berlin trea ted sewage channel Wuhle. The survival time of the above ground biomas s of the annual spe cies is relatively long due to the higher water te mperatures in winter. The average biomass of the different parts of th e flowing stretch is between 50 and 830 g DM/m(2) in summer. With decr easing concentrations of ammonia and BOD an increase of the biomass an d the colonization density could be noticed over the last few years.