Acidification of forest soils is dependent on the tree species for several reasons. One reason is that the deposition to deciduous tree species normally is considered lower than to coniferous tree species. This study therefore considers the differences in deposition to different tree species in Denmark. Canopy throughfall and precipitation were collected during the period 1986 to 1999 at three trial species experimental sites in Denmark. At each site the species Norway spruce, sitka spruce, Douglas fir, beech and oak were studied. The paper presents and discusses the differences in canopy exchange processes and dry deposition in different tree species and at different locations

The contribution summarizes outputs of annual measurements that were made in the eleven-year long period of observation (1991-2001). In this case, the liming had markedly positive effect on prosperity of spruce plantation up to now. The limed variants "surface" and "planting pit" show lower values of the total mortality than the control variant. Furthemore, the mean value of the periodic annual increment of the trees of the control variant is clearly lower than the mean values of the variant "surface" and the variant "planting pit". According to soil analyses the above described forms of liming do not seem to induce any serious negative changes within soil in this case

Wet-deposited - sulphur and nitrogen pollutants and ambient ozone are important anthropogenic factors affecting forest health. Regular assessment of chemistry of throughfall and precipitation water based on two-week sampling started in 1997. Passive samplers for detection of ozone concentration have been exposed on a network of monitoring stations during vegetation periods since 1998. In addition, in selected locations, UV absorption monitors for continuous O3 measurements were installed in 1999

The assessment of O3-like foliar symptoms is increasingly considered in monitoring programs aimed at evaluating air pollution effects on forests. The results showed considerable spatial and temporal variation of O3-like foliar symptoms: year, subplot adn the interaction between year and plot were found significant factors. Symptoms resulted lower in 2001; there were differences of foliar symptoms between different subplot and overall the variation between years are considerably different according to the plot being considered. These findings suggest that O3-like foliar symptoms recorded on a small plot selected without a formal statistical approach and with no consideration of the apparently high variability of symptoms expression risk to introduce a serious bias in the evaluation of the potential ozone impact at a given site and its trend

Soil water measurements in Swiss forest plots show a decrease of the ratio between base cations and aluminium within last 4 years. The decrease is significant in at least one soil layer in 12 of 14 plots and is strongest in areas with high acid deposition. In some of the soils the critical ratio of 1 is being reached today. The development is compared with model estimates. In Switzerland, 80% of acid deposition is made up by nitrogen compounds

The spectral reflectance curves give important information about investigated objects. High-resolution laboratory spectroradiometric measurements were used to investigate the spectral reflectance properties of spruce twigs with various foliage loss. The spectral reflectance was measured in the range from 400 nm to 1100 nm wavelength with 2 nm spectral sampling interval. Measurements of spectral reflectance were obtained using a LI-COR spectroradiometer LI-1800 equipped with standard 1/2 mm monochromator exit slit measuring 6 nm bandwidth and its external integrating sphere covered with barium sulphate inside

The main aims of the preparatory stands in air pollution areas are growth development, successfull dynamics of the plants and fast creation of the stand microclimate with favourable effect on soil conditions. This process is documented by height and diameter increment. The results confirm different growth dynamics of the particular species. Larch is the species with the best growth dynamics of selected species on experimental plots. On the other hand, beech is the worst species for reforestation in this condition. One of the causes could be damage by frost

A FORest Monitoring System (FORMS) has been implemented in Denmark in order to gain and deliver knowledge and information for operational and strategic decisions concerning nature and environment. FORMS integrate four national monitoring programmes. Forest condition monitoring is performed on 52 permanent plots distributed on a 16 x 16 km grid. FORMS gives a systematic and representative assessment of the resources in and development of the forests in Denmark, includes the monitoring of important processes in the forest ecosystem and follows the use of forest for recreational purposes

The terrestrial moss Hypnum cupressiforme was collected in the surroundings of oil plant Slovnaft (Slovakia) and oil industry in Ploiesti (Romania) to monitor heavy metal atmospheric deposition. A comparative evaluation of heavy metal atmospheric deposition recorded at the two locations versus a background area in Europe as Norway is presented. The highest concentrations were observed for V, Cr, Fe, Co, Ni and As at Ploiesti and for V, Cr, Fe, Co, and Ag at Slovnaft. This moss is very useful as biomonitoring organism to indicate and characterize deposition of atmospheric pollutants nearby oil plants

Pollution problems in forest ecosystems resulting from 100 year long operation of three smelter complexes in Central Spis are reviewed. Original data are presented with respect to temporal and spatial trends of nitrogen, sulphur and heavy metal pollution, and elemental composition of individual aerosols on leaf surface. Spruce stands in Central Spis are loaded by pollutants 1.7 times more than are critical values and the highest concentrations of As, Fe, Hg, and N were found in this region. Low Tatra National Park was the cleanest region where no element maxima were found