Lake Piburger See is situated in the Oetz Valley in the Eastern Alps at 913 m asl. Its mainly forested catchment area is 1.7 km2 in size and spans up to 2400 m asl. The lake is a protected site since 1929 and part of a Natural Reserve since 1983. During the 1960s, Piburger See suffered from eutrophication due to increasing recreational activities and fertilizer application on nearby fields. In 1970, lake restoration started with exporting anoxic and nutrient rich hypolimnetic waters by a deep-water siphoning tube (Olszewski tube) and a reduction of external nutrient loading (fertilizers on nearby fields, domestic sewage from a public bath). Consequently, the oxygen regime of the lake improved. However, hypolimnetic oxygen saturation became worse again during the 1980s, probably due to a progressively reduced discharge of the Olszewski tube. The response of phytoplankton to lake restoration was delayed by approximately two decades. The restoration of Piburger See has been accompanied by a monitoring program and by a series of master and PhD theses, addressing topics like hydrology, water chemistry, sediment, phytoplankton, zooplankton, zoobenthos, fish ecology, microbial food webs. Funding comes from the Austrian Science Foundation FWF, the European Commission and the Community of Oetz.
3 long-term data records (2003-2014) are available on Pangea: