Analysis of vegetation structure in the Natural Forest Reserve Gaisberg (Austria)

Birmensdorf

2003

S. 248-249

Artikel aus einer ZeitschriftUnselbständiges Werk

200120837

The Natural Forest Reserve (NFR) Gaisberg, 28 ha in size, has been investigated concerning vegetation composition and stand structure. The area is situated 30 km southwest of Vienna in the submontane zone and belongs to the Austrian Natural Forest Reserves Programme. To establish a phytosociological classification of the forest communities, 60 sample plots have been surveyed following the BRAUN BLANQUET method. After classification the area was mapped with respect to the defined forest associations. Additionally, stand structure has been ascertained in a systematic grid on circular plots with additional satellite plots. On the latter understorey vegetation data were collected quantitatively using the LONDO-scale. The vegetation of the NFR Gaisberg may be characterized as very rich in plant species diversity and small scaled in site and stand structure. Differences in soil conditions at the meso- and microscale and former human forest management activities might be the cause. Because of the terraced relief we found high variation in soil depths, i.e. with respect to the soil type Terra Fusca. As a consequence, water and nutrient regimes vary to a great extent, too. Human forest management is detected as a driving force of tree species composition. I.e., Fagus sylvatica was suppressed in former times to a favour Pinus nigra, Quercus petraea and Carpinus betulus. As a consequence, invasion of many plant species adapted to better light conditions and modified humus forms took place. Fagus sylvatica now starts selfreestablishment and successive shading. Natural stand develeopment without disturbance will probably lead to a decrease in plant species diversity.