A DIRT (Detritus Input and Removal Treatments) experiment was initiated at the Sikfokut Forest LTER site in Hungary in November 2000. This study was designed to evaluate how sources and quantities of litter inputs control nutrient cycling and carbon storage in forest soils across sites with different climate, C and N status. Sikfokut Forest was selected for its high N deposition rate compared the Harvard Forest LTER, Bousson Forest and Andrews Forest LTER DIRT experiment sites in the United States. Trends in soil enzyme phosphatase and beta-glucosidase activity at Sikfokut indicate that the microbial community there is already clearly responding to reduced litter availability after only two years of treatment

Forest soil condition in Slovakia harmonised with the programme ICP Forests has been monitored since 1988. There are presented some results of the first complete survey for 111 observation plots and three sampling depths (overlaying humus layer, 0-10 cm and 10-20 cm layer of mineral soil). Geological and geochemical diversity has resulted in rather differentiated forest soil condition and soil properties in Slovakia. That has strong effect on sensitivity to soil acidification as well as it brings other risks of air pollution impact

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

Passive samplers offer considerable advantages for measuring ozone (O3) concentrations in remote areas. Measurements with passive samplers typically result in data about weekly-to-monthly O3 concentrations, which are not consistent with the definitions of cumulative indices currently being used to estimate the exposure of vegetation to O3. For this reason, attempts were and are being made to develop statistical and empirical methods to estimate exposure indices like the AOT40 adopted in Europe (O3 Accumulated Over Threshold 40 ppb) starting from mean concentrations obtained from passive samplers. This paper describes an empirical method adopted in Italy to estimate 1996-2000 AOT40 values at 20 forest sites of the Italian network of intensive monitoring of forest ecosystems

This paper summarizes the data on growth response and N uptake in open-top chambers planted with ponderosa pine (Pinus ponderosa Laws.) treated with both N (0, 10, and 20 g N msub-2 yrsub-1 as ammonium sulfate ) and CO2. Both N and elevated CO2 caused increased growth. The effects of N on growth response to elevated CO2 were assessed in various ways and various interpretations could be drawn depending on which metric was used, including a negative effect of N on growth response to CO2. These calculations suggest that expressing growth as percentages can be misleading, especially when done on a grams per tree basis

The results showed that ozone specific symptoms can be detected in the needles of mature spruces in the southern Sweden with AOT40 considerably lower than the present critical level of 10 000 nl 1sup-1. The results could be expressed as an index per tree and needle generations, but also as a single value for forest stand allowing statistical tests. The results from this study support the general hypothesis and results from exposure and field studies that low nutrient concentrations or nutrient deficiency modifies the ozone response in plants. The results also show that together with low nutrition status ozone may affect the hardiness status of the needles

The mosses Pleurozium schreberi, Hylocomium splendes and Dicranum scoparium were used as biomonitors to study the atmospheric deposition of heavy metals on the territory of Slovakia. The samples of mosses were collected on 86 permanent plots. Comparison with limit values from Norway shows strong pollution of the examined areas of Slovakia with many different heavy metals. The maximum level of pollution by heavy metals was observed in the region Gemer-Spis. The most important feature of sampling is that it correlates with the European Moss-Survey-2000 and the results obtained will be incorporated in the Atlas of Heavy Metal Atmospheric Deposition in Europe

Selected parameters of the nutrients cycling process for forest ecosystem were investigated in period 1989-2000 at Prednji Vrh in the area affected by the Sostanj thermal power station. In the year 1995 desulphurization of exhaust gases from the TPP Sostanj caused considerable reduction of SO2 emission. We could not find serious tree-ring width decline in spruce. In the year 1956 and 1978 tree-ring widths rapidly declined. In the year 1995 slight icrement recovery could be observed. One probably climatically (drought) induced pointer year (1992) occurred

Small attention has been still addressed to the study of ozone effects on seminatural vegetation. Following this direction we selected an ozone heavily exposed area in Northern Italy, where the development of visible injuries on leaves of common pasture herbs were observed. The selected area, an alpine pasture located at Moggio belongs to the Level II permanent monitoring network of the ICP-Forest program. The ozone exposure mapping exercise made on the whole regional domain estimated for this area an AOT40f of 32000 ppb.h as 1999 and 2000 years average

Remarkable differences were found in soil development on three sites. At Modru Dul (the least damaged site) Sopdosols and Inceptisols were found, in Alzbetinska (moderately damaged) Entisols are common, while in Mumlavksa hora (highly damaged) the representative soils are several kind of Podzols, with variable degree of drainage restriction and organic soils. The heavy metal content is always rather low and the vertical distribution does not indicate any appreciable contribution of atmospheric contamination