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Nitrogen budget on a limestone site in the Austrian Alps
2002
Herman, F. (Institut fur Immissionsforschung und Forstchemie, Vienna (Austria). Bundesamt und Forschungscentrum fur Wald) | Smidt, S. | Englisch, M. | Feichtinger, F. | Gerzabek, M.: Haberhauer, G. | Jandl, R. | Kalina, M. | Zechmeister-Boltenstern, S.
While nitrogen input exceeded the critical loads of the WHO (1995), nitrogen deficiency and nutrient imbalances were verified by needle analyses. The atmospheric input of inorganic nitrogen was higher than the nitrogen output in 50 cm soil depth. A tracer experiment with 15N helped to prove that not more than half of the applied nitrate could be discharged. This allows the conclusion that nitrogen is stored in the system and that the site cannot yet be said to be saturated with nitrogen. The same result was also obtained by modelling
Mostrar más [+] Menos [-]Integrative study on relationships between atmospheric deposition and forest condition in German forest ecosystems using multivariate statistics
2002
Wellbrock, N. (Applied University of Forestry, Eberswalde (Germany). Institute of Soil Science) | Riek, W. | Wolf, B.
Interactions between atmospheric deposition and nutrient status or soil condition were studied using correlation analysis of the principal factors values for the year 1989. In case of both species, especially sulphur and calcium (factor 1) input is related to high foliar content of sulphur and calcium. The same influence can be detected for nitrogen (factor 3). Nitrogen inputs on Scots pine stands influenced the magnesium sufficient in a negative way
Mostrar más [+] Menos [-]The changes of Scots pine (Pinus sylvestris L.) tree stem and crown increment under decreased environmental pollution
2002
Augustaitis, A. | Juknys, R. | Kliucius, E. | Augustaitiene, I. (Lithuanian University of Agriculture, Kaunas (Lithuania). Faculty of Forest)
The main objective of this paper is to analyse regeneration regularities of damaged trees during the period of decreased environmental pollution load. Investigations concentrated on Scots pine tree height and radial increment, branch length increment, amount of branches on the verticil and needle and whole crown mass. Model trees were selected in 3 stands located on 3.5, 10 and 21 km from the plant according to their development classes and condition
Mostrar más [+] Menos [-]Implementation of remediation measures in municipal forests of Spisska Nova Ves
2002
Stefanik, J. (Municipal Forests, Spiska Nova Ves (Slovak Republic))
Spis region is due to long-term effect of air pollution one of the most polluted regions in Slovakia. Decline of trees, mostly of spruce, was recorded here altogether with disintegration of forest stands. Incidental felling and its volume is frequently connected with local source of air pollution from iron-ore works Rudnany and Kovohuty. Long-range transfer of air pollutants from Poland (Katowice) plays a certain role in air pollution as well. In the year 1994 the damaged stands were classified into the zones of endangerment, the period of the validity of forest management plan was shortened and there were proposed measures for forest regeneration
Mostrar más [+] Menos [-]Effects of elevated CO2 and O3 on silver birch rhizosphere and leaf litter decomposition
2002
Kasurinen, A. (University of Kuopio, Kuopio (Finland). Department of Ecology and Environmental Science) | Vapaavuori, E. | Holopainen, J. K. | Holopainen, T.
There is still limited amount of information about the long-term and interactive effects of increased CO2 and O3 levels on larger forest trees growing under natural or semi-natural conditions. Elevated CO2 and O3 might affect the quality and quantity of leaf litter produced and thus change litter decomposition rates and nutrient cycling in the forest ecosystems severely. In this long-term field experiment we studied the effects of realistically increased CO2 and O3 levels on fine root and mycorrhiza growth in ozone-tolerant and ozone-sensitive silver birch clones by root ingrowth core method. We measured rhizosphere soil CO2 efflux plus assessed the total fungal biomass of fine roots and soil by ergosterol analysis
Mostrar más [+] Menos [-]The influence of air pollution on contents of pollutant in some components of nature environment in the protected landscape area Ponitrie
2002
Dureckova, E. (State Nature Protection of Slovak Republic, Nitra (Slovak Republic). Protected Landscape Area Ponitrie)
Since 1990 the investigations of quality of some components of nature environment were carried out on selected permanent plots in Protected Landscape Area Ponitrie focused on pollutant contents. The increased concentration of pollutants in precipitation from the top of the Vtacnik Mts. indicates firstly the effect of the nearby thermal power station, secondly documents an increased immission load on forest ecosystems in ridge positions of these mountains
Mostrar más [+] Menos [-]Forest health research on a natural air pollution gradient in the San Bernardino Mountains, Southern California
2002
Arbaugh, M.J. | Alonso, R. | Bytnerowicz, A. (USDA Forest Service, Riverside (USA). Pacific Southwest Research Station)
Toxic effects of photochemical smog on ponderosa and Jeffrey pines in the San Bernardino Mountains were discovered in the 1950s. It was revealed that ozone is the main cause of foliar injury manifested as chlorotic mottle and premature needle senescence. Various morphological, physiological and biochemical alterations in the affected plants have been reported over a period of about 40 years of multidisciplinary research. Recently, the focus of research has shifted from studying the effects of ozone to multiple pollutant effects. Recent studies have indicated that the combination of ozone and nitrogen may alter biomass allocation in pines towards that of deciduous trees, accelerate litter accumulation and increase carbon sequestration rates in heavily polluted forests
Mostrar más [+] Menos [-]Dynamics of forest sites after liming
2002
Kunes, I. | Ulbrichova, I. (Czech University of Agriculture, Prague (Czech Republic). Faculty of Forestry)
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
Mostrar más [+] Menos [-]Forest soil condition in Slovakia and air pollution impact
2002
Pavlenda, P. (Forest Research Institute, Zvolen (Slovak Republic))
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
Mostrar más [+] Menos [-]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
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