Vegetation and rejuvenation after disturbance events (wind throw, bark beetle infestation) in spruce age-class populations in the Gesäuse National Park

In recent years there has been a strong spread of the bark beetle species Yps typographus in spruce stocks in the area of the Scheuchegg alm. The most intense infestation occurred in 2009 and 2010. In a national park, dead wood was supposed to remain in the stock and so spruce from which the bark beetles had already flew out were also left in the area of the mentioned bark beetle infestation (called young open space). However, these remaining standing deadwood logs account for only a small part of the total wood volume of the disturbance area. The larger proportion was removed. The release of the beetle broods was considered too risky for the spruce populations in the surrounding area. Due to the location on the edge of the national park, economic forests outside the park would also have been endangered. A debarkation of tribes, such as partially accomplished elsewhere in the national park, was completely renounced here. As an argument for this, the Department of Forest and Wildlife Management mentioned on the one hand the cost pressure, on the other hand, there was concern that the barked tribes would slip and endanger infrastructure below. For these reasons, most of the timber volume was removed and sold in summer 2010 and early summer 2011. For this purpose, it can be noted that in many nature conservation reserves with process nature conservation orientation, whose area sizes only reach the lower limit for large protected areas, buffer zones for the control of the book printer (Yps typographus) are already established outside the protected area. For the Gesäuse National Park, the purchase of the Waag area (neighboring economic area at Scheuchegg) was already argued in the planning phase with the creation of such a buffer zone. The future implementation of this project would be very welcome to nature conservation. In this thesis, the above-mentioned young open space is first documented in terms of its extent and current vegetation. This characterisation is primarily intended to serve as a basis for interpretation of vegetation development for future ascents or monitoring recordings. It can be anticipated that the observation of the open space is recommended in the future, as currently tree species or shrub species rejuvenation is completely lacking. Forest clearing corridors and bushes are among the particularly insufficiently studied biotope types of Central Europe (see e.g. WEBER 1999, EXNER & WILLNER 2007); subalpin even more than montan or collin, as turned out in the course of the research on this text. In order to make a small contribution to closing this knowledge gap in general, as well as to provide indications for the expected vegetation development of the young open space, the second part of the report is devoted to the vegetation and rejuvenation conditions of older forest clearing corridors in the southwestern environment of the Scheuchegg-Alm.