Investigations on Mycorrhizae and Fine Roots in an Area used as Forest Pasture

1996

S. 193-204

17 Lit. Ang.

Unselbständiges Werk

200052136

On the Schulterberg, at an altitude of 1640m a.s.l. (Achenkirch project area) , investigations on mycorrhiza and fine roots were carried out at the end of the 1991 grazing season in an area used as pasture. The evaluation of 900 cylinder samples (100ml), taken from an area of 400m2, showed considerable differences between small forest and pasture sites. Where there were trees the dry weight and the density of mycorrhizae and fine roots were higher. The diversity of the mycorrhizae and their vitality were those of a healthy forest in good condition. In areas used for granzing dead mycorrhizae and fine roots were frequently found. It is assumed that this damage, as well as the resulting poorer vitality, is due to the mechanic stress of the soil caused by grazing cattle or sheep. It is evident that the quantitative features which can be established in respect of mycorrhizae do not provide sufficient information to allow an evaluation of the site quality and that qualitative features must be taken into account for that purpose. No pollutant-related deformation of mycorrhizae was observed. From seed experiments, which can be used to assess natural regeneration, the following results have been obtained: The roots of 2-year old seedlings developed poorly on sites used for grazing, moderately around trees, and well, or even very well, on rotting wood. The feature assessed was the length of the roots. The development of the mycorrhizae also proved to be heavily dependent on the substrate and, therefore, can be used as a site indicator.