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The rate of PAHs accumulation in the pine needles (Pinus sylvestris L.) from selected regions with different types of PAHs emission
2002
Malawska, M. (Warsaw University, Warsaw (Poland). Faculty of Biology) | Staszewski, T. | Wilkomirski, B.
The investigation was carried out in three areas characterised by different levels and types of PAHs emission. The difference in total amount of PAHs in pine needles from investigated areas was accompanied by a significant changes in mutual ratio of PAHs with different number of rings
Mostrar más [+] Menos [-]Differentiation of ozone, heavy metal or biotic stress in leaves and needles
2002
Gunthardt-Goerg, M. S. | Vollenweider, P. (Swiss Federal Research Institute, Birmensdorf (Switzerland))
We aim to differentiate the various visible leaf symptoms in the field survey with microscopical methods, and to better know, how the leaf, tissue and cell response differs between injury from ozone, heavy metals (both oxidative stress) and biotic infections
Mostrar más [+] Menos [-]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
Mostrar más [+] Menos [-]The role of roots and mycorrhizas in C-sequestration under elevated CO2 (popface)
2002
Lukac, M. | Godbold, D.L. (University of Wales, Bangor (United Kingdom). SAFS)
The need to assess the role of terrestrial ecosystems in the global C cycle and the potential change of this role as the atmospheric concentration of CO2 increases attracted considerable scientific attention over the recent decade. In order to assess ecosystem responses as a whole and to evaluate the potential role of forests and tree communities as a carbon sinks, the below-ground response to increasing levels of CO2 must be addressed
Mostrar más [+] Menos [-]Needle surface structure and its relation to nutrient status of Norway spruce under the long-term air pollution influence
2002
Popierova, D. | Mankovska, B. (Forest Research Institute, Zvolen (Slovak Republic))
Emissions, especially of SO2 and to a certain degree of NOx have been reduced markedly in Slovakia during the 90s. Problems related to climate change and especially ozone are increasingly growing. The aim was to evaluate the long-term air pollution effect on forest ecosystems in mountain area with prevailing distribution of spruce through evaluation of spruce needle surface structure in relation to mineral nutrient status of trees. According to strong relationship between the coefficient of epicuticular wax degradation (Q) and accumulation of S and other elements it can be suggested that evaluation of needle surface structure by means of Q well reflects the surface status of needles
Mostrar más [+] Menos [-]Physiological ozone responses of birch (Betula pendula Roth) differ between soil-growing trees in a multi-year exposure and potted saplings in a single-season exposure
2002
Oksanen, E. (University of Kuopio, Kuopio (Finland). Department of Ecology and Environemntal Science)
Increased ozone sensitivity of larger soil-growing trees with growth in the multi-year exposure was a result of several interactive senescence-related physiological factors: lower net photosynthesis to stomatal conductance ratio at the end of the growing season promoted high ozone uptake and low photosynthetic carbon gain, leading to onset of visible injuries and impaired bud formation. This was expected to affect negatively the early growth of the next year foliage, This clone showed a major change in allocation pattern during the early ontogeny at the expense of foliage growth towards the stem height increase
Mostrar más [+] Menos [-]Diameter and diameter increment values of beech trees grown on permanent research plots with various stand densities, in the submountain vegetation tier
2002
Vosko, M. | (Forest Research Institute, Zvolen (Slovak Republic)) | Jezik, M. (Institute of Forest Ecology of Slovak Academy of Sciences, Zvolen (Slovak Republic))
The attention was focused on the diameter increment of beech timber forest growing on the partial plots with various stand density. The individual parts of the originally homogenous stand, were subjected to regeneration cutting of various intensity resulting in several partial plots. On the different partial plots we found different proportions of trees belonging to the individual diameter classes. We also found that the differences between the individual plots were statistically very significant. Beech is a tree species which is capable to continue creating considerable light increments even long after the stand opening
Mostrar más [+] Menos [-]Moderation of CO2 induced gas exchange and growth responses by elevated tropospheric O3
2002
Karnosky, D. F. (Michigan Technological University, Houghton (USA). School of Forestry and Wood Products) | Sober, A. | Sharma, P. | Kubiske, M. | Isebrands, J.G.
Stimulation of photosynthesis by elevated CO2 has been consistently found for aspen but not for maple. Similar responses have been shown for growth. In contrast, O3 causes decreased levels of photosynthesis and growth in aspen but does not appear to impact sugar maple significantly. When the pollutants co-occur, CO2 induced enhancements in photosynthesis and growth are moderated so that trees in CO2 and O3 treatments respond similarly to those in control rings. In this presentation, we will provide a physiological interpretation of our results in modelling growth response under future atmospheric conditions
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
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