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Soil acidification in Swiss forest ecosystems
2002
Braun, S. (Institute for Applied Plant Biology, Schonenbuch, (Switzerland)) | Kurz, D. | Fluckiger, W.
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
Показать больше [+] Меньше [-]Narrow-band spectral indices for foliage loss of Norway spruce (Picea abies [L.] Karst.) estimation
2002
Rasi, R. (Forest Research Institute, Zvolen (Slovak Republic))
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
Показать больше [+] Меньше [-]Effects of preparatory stands on forest site restoration
2002
Remes, J. | Podrazsky, V. (Czech University of Agriculture, Prague (Czech Republic). Faculty of Forestry)
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
Показать больше [+] Меньше [-]Forms - an integrated forest monitoring system in Denmark
2002
Bastrup-Birk, A. | Johannsen, V.K. (Centre of Forest, Landscape and Planning, Hoersholm (Denmark))
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
Показать больше [+] Меньше [-]Heavy metals in Hypnum cupressiforme collected in the surroundings of oil plants in Ploiesti and Slovnaft
2002
Oprea, C. D. (FLNP, Dubna (Russia)) | Frontasyeva, M. V. | Pavlov, S. S. | Florek, M. | Mankovska, B. | Mihul, A. | Timofte, L.
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
Показать больше [+] Меньше [-]Long-term effects of pollutants on forest vegetation in Central Spis region
2002
Mankovska, B. (Forest Research Institute, Zvolen (Slovak Republic))
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
Показать больше [+] Меньше [-]Progressive methods of increasing the survival of planting stock in the reforestation of localities affected by air pollutants
2002
Tucekova, A. | Sarvas, M. (Forest Research Institute, Zvolen (Slovak Republic))
Possibilities of the use of progressive methods in artificial regeneration of areas affected by air pollutants are namely modification of soil environment, active protection of planting stock against root desiccation, use of containerized planting stock for artificial regeneration of clearings, which resulted from air pollution
Показать больше [+] Меньше [-]Probabilistic sampling for monitoring pollution effects on forest sites
2002
Fattorini, L. (Universita di Siena, Siena (Italy). Dipartimento di Metodi Quantitativi) | Ferretti, M.
The present paper presents a list of probabilistic sampling procedures and subsequent statistical analysis, which may achieve this goal without a considerable increase of field effort
Показать больше [+] Меньше [-]Development trends of forest soils water regime under changing ecological conditions
2002
Tuzinsky, L. (Technical University, Zvolen (Slovak Republic). Forestry Faculty)
Forest ecosystems water balance research is very complicated because of forest influence upon individual components of the water balance. Global climate changes represent a real threat for forest ecosystems. In hydric area these changes concern especially thermal balance and resulting increased evapotranspiration, time and spatial distribution of precipitation
Показать больше [+] Меньше [-]The contributing role of SO2 and drought in forest decline of Austrian pine in coastal Croatia
2002
Diminic, D. (University of Zagreb, Zagreb (Croatia). Faculty of Forestry) | Hrsovec, B. | Potocic, N.
This case study confirms the role of air pollution impact on forest susceptibility to other abiotic and biotic detrimental factors. It is however very important to take into account numerous contributing factors in order to interpret or predict the degree of damage correctly
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