Aquatic Sciences

, Volume 54, Issue 3–4, pp 381–390 | Cite as

Possibilities and limitations of lake restoration: Conclusions for Lake Lugano

  • D. M. Imboden
Modelling and restoration of Lake Lugano


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.

Key words

Eutrophication phosphorus lake restoration internal restoration measures for lakes Swiss lakes Lake Lugano (Lago di Lugano) 


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Copyright information

© Birkhäuser Verlag 1992

Authors and Affiliations

  • D. M. Imboden
    • 1
  1. 1.Environmental PhysicsSwiss Federal Institute of Technology, c/o EAWAGDübendorfSwitzerland

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