Stand der Walderschliessung mit Lastwagenstrassen in der Schweiz

Abstract

Status of the forest transportation system in Switzerland with regard to roads for trucks Questions concerning the best possible forest transportation system have once again grown in significance as a result of technological developments and the current situation in the forestry and timber industry. For more than 30 years, the Swiss National Forest Inventory (NFI) has periodically recorded the condition of and changes to the forest road network. NFI4 first incorporated attributes for trafficability according to types of truck in 2013/2014, thus making possible to conduct differentiated analyses of the status of the forest transportation system. Between 1985 and 1995, 280 kilometres of new forest roads were laid every year, while only 26 kilometres of road were laid per year from 2006 to 2013 (12 km in protection forests, 14 km in other forests). In contrast, road redevelopment (reengineering) has increased, with 30 kilometres of road currently being redeveloped every year. 84% of the forest roads included in the NFI can be accessed by four-axle trucks weighing 28 to 32 tonnes in total, while 72% are suitable for five- and six-axle truck sets with a total weight of 40 to 44 tonnes. There are considerably fewer of these roads in protection forests than in other forests. The road density in Switzerland for 28- to 32-tonne trucks totals on average 22 metres/hectare, though this varies widely from region to region (ranging from 2 to 57 metres/hectare in production regions and from 0 to 84 metres/hectare in forested areas). Based on harvesting methods currently applied at local level and the corresponding optimum and maximum transport distances, 46% of useable forested areas in Switzerland is good, 29% is moderately good, and 25% is poor or undeveloped. The percentage of poor or undeveloped forests is highest in the Alps (44%) and the south side of the Alps (53%). In the Alpine foothills the percentage of poor or undeveloped forests is 13%, in the Jura Mountains 5% and on the Plateau 2%. A current study of the Swiss Federal Institute WSL is striving to determine the potential scale of the need for transportation systems in the future upon application of the best harvesting methods.