Assessing hypolimnetic stress in a monomictic, eutrophic lake using profundal sediment and macrobenthic characteristics

Summer-winter variations of the physico-chemical features of profundal sediments and of the characteristics of the profundal benthic community in a small, monomictic and eutrophic fake were analyzed in order to define their relations to environmental stress in the hypolimnion. The sediments were rich in P and N compounds. The benthic fauna exhibited a very poor taxa richness and diversity in summer, probably due to reduced oxygen in the hypolimnion, and there was only slight improvement of these community parameters in winter when reoxygenation occurred. The macrofauna was influenced by both sediments and overlying waters.