Critical loads were estimated for over more than 1400 receptors supporting forest vegetation in northern Belgium using simple mass balance method. Necessary data were derived from old historical soil database, recent data from forest surveys, meteo data, level I and II plots and regional studies concerning elemental sequestration in woody biomass. Deposition estimates were performed with the OPS-model, which had been validated with deposition measurements of N and S in 6 level II plots over the period 1994-1998. In addition, an edge enhancement factor was calculated to account for enhanced deposition in plots situated in forest edges

Forest Scientists must recognize that numerous diseases and insect occurrences as well as more subtle environmental stresses are prevalent as causes of changes in forest health. Their interactions often lead to "natural" declines of individual tree species or site-species declines of multiple species. The role of air pollution should be carefully investigated in an integrative sense with these other endemic and sometimes epidemic outbreaks of biotic agents and environmental stresses.

The article presents a state of art of forest decline inventories in Slovenia. The first part deals with methodological and technological aspects of forest health inventories, while the second one describes some hints and directions of further forest inventories development.

The Forest Research Plot was chosen on a typical site for the Pokljuka plateau. It is covered by a supposedly autochthonous old Norway spruce stand with rejuvenation centres. Data on the physiological parameters can be used as representation values for a subalpine Norway spruce stand. The studies include: standard site and dendrological parameters, physiological parameters (foliar analysis, antioxidants, hormones and aminoacids in spruce needs), genetical and biochemical analysis (isoenzymes and molecular markers), microbiological activity (acid phosphatase, rate of decomposition, number and occurrence of fungal decomposers of wood and litter) and studies of symbionts and pathogens of Norway spruce (mapping of fruitbodies of mycorrhizal fungi, types of ectomycorrhizae, endophytes, epiphytes - lichens and phytopathological surveys). All physiological and ecological studies are planned to be repeated at certain time periods in order to understand better the functioning of the forest ecosystems on Pokljuka.

This paper deals with presenting a broad range of possibilities, which can be used with computer equipment by deriving, interpreting and processing forest data. Different rates of generalized data from the forest inventory can be used as a criterion in preparing different solutions. So this data strongly influences decision making processes. The paper also presents cost analysis and multi-criteria evaluation methods.