The soil water retention potentials and other hydrolimits of individual soil horizons of podzolized soil were determined in the stand of Picea abies (Mecuvka, the Beskids, Czech Republic) on godulic sandstone. Different hydropedologic characteristics for the individual soil horizons were found. Extreme values were detected for the albic E horizon, which importance for water and nutrient status of forest stand on podzolic soil is discussed.

In the region of Knehyne-Velka Stolova in the Moravian-Silesian Beskids, where there are ecologically difficult conditions for functioning forest ecosystems, possibilities were studied for the naturat regeneration of beech. The study of problems was particularly related to generative propagation, however, cases of vegetative propagation were also found. Potential possibilities of regeneration are related to the seed year 1995. Rooting ability of layered branches or lying beech trees wes studied. Analysis is given of a rooting beech branch.

The studies of grass communities, which spread in deforested areas, also involved observations of soil thermal regimes. Three sites were chosen in order to determine differences in diurnal and seasonal variations of soil temperatures: (1) open site (barren) without plant cover, (2) site covered by a young, lower and thinner stand of Avenella flexuosa, and (3) old, dense stand of Calamagrostis villosa with a layer of plant litter on the soil surface. Soil temperatures were measured at the soil surface and in the soil depth of 5 and 10 cm. In summer months, the greatest differences in maximal temperatures recorded at the soil surface and at the 5, 10 cm depth between the bare site and the old stand of C. villosa represented 21.6, 15.9, 12.4 deg C, respectively. Soil temperatures measured in the bare plot in autumn months were lower than those in grass stands.

The cloned saplings of Norway spruce (7 years old) were exposed to ambient UV-B irradiation or enhanced BV-B irradiation (+25 %) continuously over three growing seasons. Comprehensive analysis of CO2 assimilation and chlorophyll a fluorescence was performed at the end of the third growing season to evaluate the influence of enhanced UV-B irradiation. The analysis resulted in observations of decreased photosynthetic activity, mainly of RUBISCO activity, as a result of long-term influence of enhanced UV-B irradiation. Morever, the deep impact of enhanced UV-B irradiance on the level of electron transport and thus enhanced sensitivity to photo-inhibition was demonstrated.

According to the geostatistical methods annual sums of precipitation, mean annual concentrations of SO2, total potential deposition of sulphur as inputs to the mountain forest ecosystem of Moravian-Silesian Beskids on the spatial level in 1996 were derived. For this purpose, all possible meteorological and monitoring stations in the surroundings of the cesearch teiritory were used.

Some 30 species of cambioxylophages with the dominant position of Pityophthorus pityographus, Polygraphus poligraphus, Pityogenes chalcographus, Molorchus minor and Obrium brunneum were recorded on subdominant trees attacked by Armillaria sp. and Heterobasidion annosum. The stress induced by fungal pathogens on subdominant trees causes unfavourable conditions for the development of Ips typographus and increases attractiveness for P. poligraphus and M. minor. Species of P. chalcographus and P. pityographus response indifferently.