Forests provide more effective protection against natural hazards than even experts in the field believed up to now. Maintaining forests is considerably cheaper than building costly technical structures. But can the forest guarantee a similar level of safety to structural measures? The Protect Bio method enables the evaluation of this nature-based protection service. As part of this project, a method was developed which makes it possible to determine the effect of the forest and other biological protection measures and to take them into account accurately in hazard protection projects.
Reforestation of slope near Davos to limit snow avalanches
The Kaunertal Valley in western Austria is experiencing glacier retreat, and the southern part of the valley, the ‘Gepatschferner’ glacier, is one of the fastest melting glaciers in Austria. This glacier retreat leaves unconsolidated sediments in steep lateral moraines exposed to erosion and subsequently rock fall, debris flows, and shallow landslides decreasing the slope stability in the proglacial. The Kaunertal pro glacial area will serve as a concept case where climatic changes, such as the increase in frequency and severity of extreme events, impose strong threats to the region.
Mountain forests (esp. protection forests) play a crucial role in protecting people, permanent human settlements and infrastructure in Alpine settings.The environmental and social benefits in this case study are:(i) Securing the protective function of forests against natural hazards (floods, mudslides and landslides) and(ii) enhancing social and economic vitality (including ecological stability) of the region.
Following 2005 floods, the dikes at the Obere Iller section Fischen were relocated and the foreland area was set deeper. Additionaly the Iller was widened.
In recent years, the city of Sonthofen has acquired seven plots of land with a total area of more than 11 hectares for the purpose of restoration in the Strausbergmoos. In 2011, the Landschaftspflegeverband Oberallgäu-Kempten e. V. had a maintenance and development plan drawn up by three renowned moorland experts (Ringler, Quinger and Siuda). Already in 2012 the bed of the Löwenbach was raised to protect the Strausbergmoor, because as a result of the stream straightening and stream deepening, large parts of the Stausbergmoor threatened to slide into the stream.
Following 1999 floods, the Obere Iller was widened in the Section Sonthofen / Ofterschwang and new retention areas were created.
In the course of the extension of the flood protection, the Ostrach was also expanded and ugraded ecologically. The river bed was widened, as far as the existing local utilization conditions allowed it. All exisiting drop structures were replaced with river bed ramps to improve the ecological passability. Groynes and large stones were implemented to improve the flow diversity.
In order to protect the Kematsrieder Moos against dehydration youths and young adults of the BUND Naturschutz Jugendorganisation (JBN) have dammed up ditches in the Kematsrieder Moos by hand.
The core of the Hagspielmoor is crossed by drainage ditches. Through these ditches the moor is still continuously drained, which leads to further degeneration. The district group Lindau of the Bund Naturschutz will carry out In several steps extensive scrub clearance and ditch closures. The measures will be implemented in cooperation with the Bergwaldprojekt e.V., which will carry out manual ditch closures and scrub clearance with the help of volunteers.