Der Einfluss von gereinigtem Abwasser auf das Phytoplankton in Seen

The effect of domestic sewage effluents after a) mechanical, b) mechanical-biological and c) mechanical-biological-chemical treatment on algal cultures and on natural lake phytoplankton was studied by means of laboratory assays and in situ experiments. The concentrations of phosphorus and nitrogen are almost exclusively responsible for any algal growth. Other constituents which may be present in sewage effluents (e.g. residual amounts of iron originating from the tertiary treatment) do not stimulate substantially the growth of algae.