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Bioindication of immmission load lowering with change of the aluminium production technology
2002
Mankovska, B. (Forest Research Institute, Zvolen (Slovak Republic))
Problems of the environment pollution in Ziarska basin are connected with the operation of Aluminium plant from 1953. After replacement of old production technology by a a new one by Norwegian company Hydro Aluminium emission of dust of Al2O3 dropped from 766 tons per year to 243 tons per year, emission of fluorides dropped from 847 to per year to 65.9 tons per year and of SO2 have increased from 716 to 974 tons per year. The mentioned reduction of emission reflected markedly in a great reduction of vegetation loading by fluorine. In the year 2001 we found statistically sifnificant difference for total Ksupz (coefficient of loading) in coniferous and broadleaved tree species in A polution zone in comparison with the zone B, C and D
Show more [+] Less [-]Development of macroscopic markers of Norway spruce damage in the Krusne Hory between 1998 and 2000
2002
Polak, T. | Albrechtova, J. (Charles University, Prague (Czech Republic). Faculty of Science) | Rock, B. N.
The average defoliation of the sites located in the western part significantly increased in 2000, probably as a result of massive needle yellowing and shedding, and the G/A bud ratio decreased for all of the sites what reflected in reduction of crown regeneration. We suppose that a further increase of crown defoliation due to exceedance of stress threshold may trigger tree defensive reactions and replacement of the loss of assimilative organs
Show more [+] Less [-]Effect of increased carbon dioxide and ozone on leaf spot pathogens of birch
2002
Syrjala, L. | Poteri, M. (Finnish Forest Research Institute, Suonenjoki (Finland). Suonenjoki Research Station)
Both CO2 and ozone increased the diseased leaf area of clone V5952 in Exp. 1 in the year 2000. The size of spots increased most under ozone fumigation, and the number of spots under ozone and CO2 + O3 fumigations. In clone K1659 all fumigation treatments decreased or had no effect on the DLA, or the number and size of the leaf spots. Also the number of fallen leaves under fumigation treatments was higher in clone V5952 than in clone K1659. Analysis of the year 2001 monitoring results is currently going on
Show more [+] Less [-]Linking air pollution and forest health: how are we doing?
2002
Percy, K. E. (Natural Resources Canada, Fredericton (Canada). Canadian Forest Service-Atlantic Forestry Centre) | Karnosky, D.F.
Scientific concern over air pollution impacts on forest health and ecosystem function have evolved from local (point-source), to regional (area source) and ultimately to the global scale (increasing atmospheric CO2). All three scales of investigation remain relevant to increasing our understanding of how air pollution affects forests. Presently, linking air pollution with forest health status through routine monitoring network data remains problematic. In this paper we present a brief overview of air pollutant trends, together with recent European forest condition monitoring and FACE experimental case-study evidence to illustrate the need for multiple-level investigation of air pollutant-forest interactions
Show more [+] Less [-]Consequences of elevated CO2 and O3 on birch canopy structure
2002
Kull, O. (University of Tartu, Tartu (Estonia). Institute of Botany and Ecology) | Tulva, I. | Vapaavuori, E.
We studied elevated CO2 and ozone effects in single and in combination on crown structure of two Betula pendula clones. Shoot ramification, shoot length, number of metamers, leaves and buds were measured at four heights in every tree. Chamber effect was substantial on sylleptic branching and on shoot length and ramification. However these responses differed between the clones. Ozone treatment affected shoot length and caused slight decrease in shoot ramification. Elevated CO2 affected appearance of long shoots in complex manner, but in lower crown positions CO2 caused increased number of long shoots in both clones
Show more [+] Less [-]Acid rains in Belgrad forest, Istanbul
2002
Serengil, Y. (University of Istanbul, Istanbul (Turkey). Faculty of Forestry)
The results showed that the hydrogen load had a very significant variation between the two monitoring years. In 1999-00 water year, hydrogen load was 4.72 kmol/ha, while in 2000-01 it was 1.70 kmol/ha. Although the observed pH values of rainwater never got over 7.0, high values around 6.0 were determined in summer moonths. The average equivalent concentrations of measured ions were calculated and an equilibrium between anions and cations was found
Show more [+] Less [-]Implementation of remediation measures in forests with the emphasis on the forests in Spis region
2002
Vosko, M. (Forest Research Institute, Zvolen (Slovak Republic))
Major part of implemented measures was aimed at early artificial forest regeneration and securing plantations, or protection of young forest stands against damage by bark beetles. Only exceptionally there were proposed measures with the aim to increase vitality, stability and improvement of the structure of forest stands by their tending. It was worked out a draft of procedures for forest managers to help them in deciding at which stocking it is necessary to reforest reduced or actual clearings, whether to fell down open stands or to leave them regarding their age, state and expected further development
Show more [+] Less [-]Foliar elements of Scots pine across the transect from the ammonia emission source (1995-1998)
2002
Kupcinskiene, E. (University of Agriculture of Lithuania, Kaunas (Lithuania). Kaunas-Akademia)
Significant correlations (p0.05) were found between the concentration of elements in the c needles and the distance of the sites from nitrogen ferilizer factory (NFF): the amounts of C, K, Mg, Zn, and Rb in the c+1 needles were increasing, whereas concentrations of N, P, Al, Mn, Cu, Ni, Sr and Cd were decreasing alongside the transect from NFF. Statistical analyses performed on logarithms and estimation of components of variance by maximum likelihood has shown that the age of the needles and the sites were the most important, while year of sampling was much smaller source of variance. Only a few significant differences were found comparing the amount of elements in Scots pine needles collected in four-year space
Show more [+] Less [-]The ecophysiological indicators of air pollution stress of beech (Fagus sylvatica L.) in Zasavje area, Central Slovenia
2002
Kalpic, A.B. (Ecological Research and Industrial Cooperation, Velenje (Slovenia)) | Lasnik, C.R.: Simoncic, P.
Several investigations about air pollution impact on forests have been carried out in Slovenia during last thirty years, mainly using the Norway spruce (Picea abies [L.] Karst.) as the main bioindication species, but there is a lack of information about common beach (Fagus sylvatica L.) condition, the most important forest tree species in Slovenia and in Zasavje area. The assessment of air pollution effect on beech based on stress physiological indicators of foliage, macronutrients level in beech leaves and by assessment of crown defoliation was carried out altogether with necessary soils analyses of the selected beech stands. On the basis of all parameters it can be concluded that the worst condition of beech trees in Zasavje is due to high level of air pollution, mainly by sulphur dioxide and not by deficiency of macronutrients or unfavourable state of soils
Show more [+] Less [-]Effect of increasing ozone and carbon dioxide on photosynthetic and related biochemical properties of two silver birch clones during three years of exposure
2002
Riikonen, J. (Finnish Forest Research Institute, Suonenjoki (Finland). Suonenjoki Research Station) | Holopainen, T. | Oksanen, E. | Vapaavuori, E.
Under elevated CO2 photosynthesis was 15-50% higher than in chamber controls depending on the weather conditions of the growing seasons. When measured at 360 ppm CO2 both elevated CO2 and elevated CO2 + O3 treatments decreased net photosynthesis, stomatal conductance and also transpiration, indicating downregulation of photosynthesis at elevated CO2
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