Lake Kinneret, the nutrient chemistry of the sediments

Lake Kinneret plays an important role in the water supply of Israel. Since the sedi-ments may actively contribute to the nutrient supply causing the winter algal bloom, an extensive study of the mud-water exchanges has been undertaken; the first results are reported here. The concentrations of Fe, Mn, P, N, organic-C, and CaC03 in recent sediments have been determined for the whole lake and the results discussed in the light of the chemical conditions of bottom waters, the detrital input, and the plankton compo-sition. Only 4 % of the total autotrophic carbon is withdrawn from the lake cycle by the sediments. The lake muds concentrate phosphorus in spite of the prevailing reducing conditions, which suggests an active physical adsorption. Conclusions are drawn concern-ing the role of clays as “nutrient fixer ” and concerning lake management