Abstract
In most lakes eutrophication is linked to an excessive input of phosphorus. Lake restoration by reduction of P-input (external measure) has led to a considerable drop of the P-concentration in all major Swiss lakes as well as in many other lakes. Internal restoration measures such as artificial mixing, drainage of hypolimnetic water, flushing, aeration, biomanipulation and others serve to improve and accelerate the response of a lake to external measures. For the case of Lago di Lugano, a simple two-box model is employed to demonstrate that a reduction of the P-input to about 25% of the present values is necessary to reach the “P-criterion” (P-concentration below 30 µg/l). Internal measures could possibly accelerate the extremely slow response of the northern basin.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
Ambühl, H., 1982. Eutrophierungskontrollmassnahmen in Schweizer Mittellandseen. Z. Wasser-Abwasserforsch. 15:113–120.
Benndorf, J., 1987. Food web manipulation without nutrient control: A useful strategy in lake restoration? Schweiz. Z. Hydrol. 49:237–248.
Gächter, R. and D. M. Imboden, 1985. Lake restoration. In: W. Stumm (ed.), “Chemical processes in lakes”, Wiley-Interscience, New York, p. 363–388.
Gächter, R., A. Mares, E. Grieder, A. Zwyssig and P. Höhener, 1989. Auswirkungen der Belüftung und Sauerstoffbegasung auf den P-Haushalt des Sempachersees. Wasser, Energie, Luft 81:335–341.
Imboden, D. M., 1987a. Restaurierung von Seen: Eine multidisziplinäre, ökologische Aufgabe. Gas-Wasser-Abwasser 67:427–432.
Imboden, D. M., 1987b. Restoration of a Swiss lake by internal measures: can models explain reality? Proc. Internat. Congress on Lakes Pollution and Recovery, Europ. Water Poll. Control. Assoc., Rome, April 1985, p. 29–40.
Müller, R., 1992. Trophic state and its implication for natural reproduction of salmonid fish. Hydrobiologia/Dev. Hydrobiol., in press.
Rast, W., R. A. Jones and G. F. Lee, 1983. Predictive capability of U.S. OECD phosphorus loading — eutrophication response models. Journal WCPF 55:990–1003.
Ripl, W., 1976. Biochemical oxidation of polluted lake sediment with nitrate. A new lake restoration method. Ambio 5:132–135.
Sas, H., 1989. Lake restoration by reduction of nutrient loading. Academia Verlag Richarz, Sankt Augustin, 497 pp.
Vollenweider, R., 1976. Advances in defining critical loading levels for phosphorus in lake eutrophication. Mem. 1st. Ital. Idrobiol. 33:53–83.
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Imboden, D.M. Possibilities and limitations of lake restoration: Conclusions for Lake Lugano. Aquatic Science 54, 381–390 (1992). https://doi.org/10.1007/BF00878149
Received:
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/BF00878149