Trübeströme in Seen: Sauerstoffeintrag durch grundnah eingeschichtetes Flusswasser

Near-bottom current measurements in the main delta areas of the Walensee (Switzerland) and of Lake Constance yielded evidence that sporadic high influxes of clastic suspensions caused by flood stage discharges of tributaries generate turbidity underflows. Turbid suspensions plunge down the delta front as hyperpycnal inflows with speeds up to 130cm/s. These periodic intrusions of well oxygenated river water may influence the oxygen budget of the basal hypolimnion, thus possibly antagonizing eutrophication in marginal cases, supported by the adsorption of phosphate by suspended clay particles.