Lake Muzzano, Ticino, Switzerland is a highly eutrophied anoxic shallow lake with reccurent algal blooms. In 1998, a bypass to diverge sewage water was installed to limit the input of nutrients. Although the amount of nutrients was indeed decreased, algal blooms are still occuring. To determine how to better restore this lake, a sampling campain was started in March 2012 and will soon end in May 2013. This project included: - Monthly analysis of nutrients in inflows and outflow - Monthly analysis (nutrients, temperature, pH, oxygen) of lake water - Evaluation of the sedimentation rate in three sediment traps installed at the major inflow, in the middle of the lake and at the outflow - Sediment analysis (LOI), chironomids and diatoms in a sediment core to reconstruct anoxia and total phosphorus through time and to evaluate the baseline conditions.
Based on these results, it was determine that although nutrients still come in the lake, changes in lake circulation was the first factor leading to anoxia and algal blooms.
The report will be available once the project is completed and approved.