VAR TAR EMISSIONER FRÅN FISKODLINGAR VÄGEN? / Where are the emissions from fish farms in lakes?
This work presents results from a sedimentological investigation of Lake Södra Bullaren, Sweden, and a budget suspended matter for the lake. The basic question concerns the spread offeed wastes and faeces from a fish farm. Where do these emissions appear? Are they large in comparison to other fluxes of marerial causing increase in total-phosphorus-concentrations and oxygen-consumption? The basic aim of this work is to discuss some fundamental, general aspects in quanritative evaluations ofenvironmental effects of fish farms. The data om Lake Södra Bullaren provide a case-study. The results are summarised in a flow-diagram, which shows that about 5200 tons of sedimenting material emanate from tributary inputs and lake primary production. A fish farm producing 500 tons ofrainbow trout per year used 450 tons of dry feed (pellets). About 80 % (or 350 tons) of this is used for growth and respirarion of the culdvated fish. “Complete abstract not presented.”