The ectomycorrhizal biodiversity of selected Norway spruce stands on an Alpine limestone mountain was studied by inventories of occurring fruitbodies and descriptions of new ectomycorrhizal types. Based on fruitbody surveys a total of 137 ectomycorrhizal and 48 saprophytic species was recorded. Dependent on elevations as well as microclimatic, soil, and stand conditions there were significant differences in the fungal composition and number of species between the investigated forest plots.

The use of ectomycorrhizal fungi as possible indicators of ecosystem response to disturbance is discussed with emphasis on the analysis of individual species by direct observation of their mycorrhizas. Some examples of such studies are given. The possible role of fungal diversity and differential tolerance by individual species to pollutants are also discussed in relation to observed changes within ectomycorrhizal fungal communities.

In 1992, a monitoring survey on a national scale was carried out using Hypogymnia physodes (L.) Nyl. as a biomonitor for trace element air pollution. The primary aim was to analyse epiphytic lichens collected at 86 sampling locations of the 16 x 16 km bioindication grid using k(0)-based instrumental neutron activation analysis (k(0)-INAA), and X-ray fluorescence spectrometry (XRF) for sulphur and lead, to obtain information about the levels of elements in the atmosphere and to identify significant pollution sources. The geographical concentration patterns of the trace elements obtained from the lichen data were mapped and compared with the index of atmospheric purity (IAP) calculated on the basis of data from lichen thalli type mapping, obtained on a more dense bioindication grid in 1991. The results obtained showed good agreement between the mapping of sulphur and trace elements with the status of lichen vegetation. The most exposed regions with elevated trace element levels and lower values of IAP were in the north-western Alpine part of Slovenia which coincides with high precipitation, and in the east of Slovenia, where many local pollution sources are situated.

Forest soil was sampled on two different observation plots by following well described methodology. Sampling sites had been chosen in place with typical soil conditions for the observed forest site. To make sampling easier some natural forest site characteristics were considered. Mg, Zn and Cd were determined by atomic absorption spectroscopy in all samples. Results were statistically evaluated and different sources of variance were estimated. It was also estimated whether the number of samples was sufficient for our requirement for accuracy of analytical results.