Protective Forest and Natural Hazards

The effect of the forest in terms of its effective protective function for the preservation and development of habitat and quality of life is the focus of both teaching and research of the mountain forest group of the Institute for Alpine Natural Hazards (IAN).

Mountain forests make an important contribution to the protection against natural hazards in the alpine living and traffic area. By counteracting soil erosion, improving the hydrological and climatic conditions at the site and maintaining the regulating ecosystem services, forests reduce the risk of natural hazard processes such as avalanches, landslides, rockfall, debris flows, sediment transport and floods. This so-called indirect protective effect of the forest refers to the conservation of the forest site itself. Such forests are therefore also called site protection forests. However, forests also have a direct protective function, namely when people, human settlements or facilities or cultivated soils are directly threatened by natural hazards. Forests with a direct protective function are also called site protection forests. Irrespective of whether indirect or direct, the protective function of forests usually extends over a larger area of disposition (areas with an increased probability of occurrence of processes relevant to natural hazards) than can be achieved, for example, by technical measures.

The research group "Mountain Forest" can refer to one of the oldest and first concepts for the protection against natural hazards and thus to a wealth of experience, which goes back to one of the very first specialisations of the Institute of Alpine Natural Hazards. About 15 years ago, the graduates of the study course on protection against natural hazards were almost exclusively forestry students. As the handling of natural hazards changed over time, so did the challenges to be mastered and with them the complexity of the matter. Nowadays, natural hazard processes and their challenges are viewed from different perspectives by different disciplines (a reason also for the various research groups at IAN). The strategy of the Mountain Forest Group is to be operative on an interdisciplinary and thus transinstitutional level. This explicitly includes the willingness to cooperate with different research fields as well as the use, processing and continuation of previous research achievements on the topic of forests and natural hazards. In addition to international cooperation, this means above all targeted cooperation with other BOKU institutes.

Due to its explicit willingness to cooperate with different research fields, the Mountain Forest Group sees itself as a partner in the competence fields of water-atmosphere-environment, soil and terrestrial ecosystems, but also in the competence fields of habitat and landscape, renewable raw materials and resource-oriented technologies and resources.

The mountain forest group faces the following challenges for the future:

• How much natural resources are needed to ensure sustainable protection against natural hazard processes such as snow/avalanches, rockfall, erosion/slides and torrent processes (from floods to debris flows)?
• How great is the influence of land use and land-use changes in the "ecosystem" torrent catchment area?
• What is the role of climate change (global warming and social adaptation) on the protective effect of forests? Indirectly (natural disturbances such as beetles, wind) and directly (afforestation at high altitudes, adaptation of forest communities)?
• Which strategies are needed to maintain or improve the water or soil balance in the sense of the supporting ecosystem services of a torrent catchment area?
• What is the direct role of the forest in hazard delimitation and planning of measures against natural hazard processes in terms of regulating ecosystem services?
• How can we manage natural resources and habitat development sustainably? Which combinations of technical and near-natural measures to reduce the occurrence of natural hazard processes help us to do so?