We know forests from the train window, enjoy them while hiking or see them while skiing in alpine valleys.
In doing so, we perceive the lush green in spring, perhaps the animals living there and beautiful autumn colours. However, the many functions that forests provide to protect our settlement and living areas remain invisible.
For example the canopy catches up to 70 percent of the amount of new snow and thereby reduces the danger of avalanches. The stems serve as a natural protection against rockfall, the roots penetrate the soil. In this way more water is stored in the soil and the danger of floods is reduced. Moreover, forests are the best means of erosion control.
In Austria the protective function of forests are outlined and defined in the Forestry Act, amended in 2002. Under the over-all term “protection forest” (now referred to as “protective forest”) this law distinguishes between site-protecting forests (section 21), object-protecting forests (section 21) and protective forests declared by official notice (“Bannwald”) (section 27).
Protective forests in Austria
According to the map of potential protective forests approximately 42 percent of Austria’s forest area have a protective function - that are nearly 1.6 million hectares. Almost every fourth Austrian benefits from the protective effects of forests.
Site-protecting forests are forests whose sites are threatened by the eroding forces of wind, water or gravity. They require special treatment to protect the soil and the plant cover and to ensure reforestation.
Site-protective forests can be found for example
- on wind-blown drifting sand or drifting soil,
- on sites that tend to the development of karst or that are particularly prone to erosion,
- on rocky, shallow grounds or steep locations,
- on slopes where slides might occur,
- in the timberline zone.
The protection and tending of site-protective forests ensure that soils - and thus important resources - are preserved. The stabilising measures are to be carried out by the owner of the forest concerned where costs can be covered from the proceeds of felling. In addition, unstocked areas have to be reforested. This guarantees sustainable forest management.
Object-protective forests (as defined in the Forestry Act) are forests that protect humans, settlements, infrastructure facilities or cultivated soil against natural hazards or injuring environmental impacts. They could stop for example avalanches and rocks, prevent land slides and store run-off precipitation water. Special treatment is required to ensure their protective effect.
The forest areas with an object-protective effects are shown in the map of potential protective forests.
The owner of a protective forest has to manage the latter in a manner ensuring a vegetation of optimum stability, appropriate to the location and with a strong inner structure. Unstocked areas have to be reforested. Forest owners can obtain financial support from public means or by payments from beneficiaries.
Protective forests declared by official notice (“Bannwald”)
“Bannwälder” are forests declared protective by official notice to directly ward off certain dangers. The official declaration as a protective forest means that the forest authority requires the relevant forest owner to implement necessary actions or to refrain from taking certain actions. If this entails financial disadvantages forest owners are entitled to compensation.
The purposes of declaring a protective forest by official notice include
- to protect against avalanches, rockfall, landslides, floods and wind
- to protect medicinal springs, water resources, centres of tourism and conurbations against negative Impacts
- to secure traffic facilities
Austria has about 12,000 hectares of “Bannwald”.
Shelterbelts / Windbreaks
Shelterbelts, or windbreaks, protect agricultural soils against erosion by wind and serve to hold snow. In this way they contribute significantly to the protection and preservation of the soil, which is a finite resource, meaning its loss and degradation is not recoverable within a human lifespan.
Shelterbelts are strips stocked with native trees and shrubs in our cultivated landscape that
- serve agriculture to ensure its production
- provide habitats for the natural fauna and flora
- provide people with diverse landscapes
"Fighting Zone" of the forest near the treeline
The term "fighting zone" of the forest means the area in alpine locations where the forest is already quite fragmented due to climatic conditions so that trees may only grow sparsely and sporadically. The trees thus virtually "fight" for their survival especially during extreme winter conditions, high wind speeds or frequently occurring fungal infections. For those areas the same regulations of the forestry act as for object-protective forests apply, assuming a high protective effect of the vegetation.
Riparian forests are an important part of river ecosystems. Originally, large forested areas stretched out on both sides of the river, frequently interrupted by side arms that were mostly flooded in case of floods. Today, according to the Inventory, there are about 95,000 hectares of riparian forests in Austria. Such forests provide a habitat for many animals, birds and insects but they also fulfill another important protective function for our society. During floods riparian forests can retain large amounts of water and sediments and thus serve as an important retention area.
Protective Forests "in yield"
Protective forest "in yield" can - of course taking its important protective function into account - be managed in an economically positive way as well. When measures are implemented it is important to ensure that the existing site characteristics are preserved and that the most stable forest stand is guaranteed. This is particularly the case in steep locations.
Protective Forests "out of yield"
Protective forests without yield are protective forests in locations that are difficult or impossible to access where no or only insignificant amounts of wood are used. Also included are stands with a rotation period of more than 200 years or those on shallow sites without any profit.
Protective function and protective effect
The terms “protective effect” and “protective function” of the forest are often used synonymously. However, it is useful to explain the technical differences in a nutshell.
The forest function is a task assigned to the forest by society to provide a specific service, for example the task of the forest to protect against damage caused by natural hazards. The function thus depends on the location and on spatial planning.
The effect of the forest describes the extent and the impact of the fulfilment of a task. Thus, the effect of the protective forest depends on its actual condition, that includes the tree species composition, the horizontal and vertical structure of the forest stand as well as the distribution of the tree diameters.
The management of a protective forest as well as the maintenance of its protective functionality is always accompanied by great challenges. Many forest areas are overaged, young trees are missing. In addition, those forest areas are difficult to access and financial challenges arise, whether expensive forest maintenance measures or the low price of wood. In addition, there are often conflicting interests, too high levels of game or calamities, such as mass growth of harmful organisms or windthrow, which are enormous challenges, especially in protective forests.
In order to meet the various challenges, a sustainable Austrian forest policy is needed to improve our protective forests.