خيارات البحث
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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
اظهر المزيد [+] اقل [-]Science and policy - to what extent does long-term monitoring of forest ecosystems contribute to policy relevant air pollution issues?
2002
Haussmann, T. (Federal Ministry of Consumer Protection, Food and Agriculture, Bonn (Germany)) | Fischer, R. | Riebau, A.
Following the objective to provide an overview on the spatial and temporal variation in forest condition on a European scale, an extensive systematic survey on more than 6000 so called Level I plots throughout Europe is carried out. Results show a recuparation of crown condition in the mid nineties and a resuming deterioration with nearly a quarter of the sample trees classified as damaged in 2001. Results of statistical evaluations explain the observed variation mainly by weather extremes, insects, fungi and indirect effects of air pollutants via soil acidification or changes in the nutritional status of trees
اظهر المزيد [+] اقل [-]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
اظهر المزيد [+] اقل [-]Epiphytic lichens as air quality indicators in forest stands
2002
Mavsar, R. (Slovenian Forestry Institute, Ljubljana (Slovenia)) | Batic, F. | Jeran, Z.
An outline of the analyses of experimental material from the 2000 moss survey is given. It includes some selected areas in Central Russia, Bosnia, Bulgaria, Romania, Slovakia and Serbia. Applying this methodology to areas of Central and Eastern Russia, not yet covered by the European moss surveys, will significantly broaden our understanding of air pollution in Europe
اظهر المزيد [+] اقل [-]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
اظهر المزيد [+] اقل [-]Ectomycorrhizal associations in Norway spruce stands influenced by long lasting air pollution (Silesian Beskid Mountains, Poland)
2002
Rokicka-Kieliszewska, B. (Polish Academy of Sciences, Kornik (Poland). Institue of Dendrology) | Rudawska, M. | Staszewski, T. | Kurcynska, E. | Karlinski, L.
Norway spurce (Picea abies L.) is the dominating tree species in the Silesian Beskid Mountains. The mountain forests are under severe climatic conditions, such as low temperatures, short growing season, strong winds, high annual precipitation, a long-time snow cover. The forests have been exposed also for about half century to gaseous and dust pollutants emitted by large industrial centres in the Czech Republic, Germany and Poland. Anthropogenic impacts may influence negatively the growth of tree fine roots, can develop ectomycorrhizas and alter the communities of ectomycorrhizal fungi and other microorganisms in soil. Ectomycorrhizal communities at the both forest sites were dominated by the same two morphotypes, which were further studied using the PCP-RFLP analysis for identification of the fungal species
اظهر المزيد [+] اقل [-]Long-term effect of alkaline air pollutants on forest ecosytems
2002
Caboun, V. | Mindas, J. | Priwitzer, T. | Pavlenda, P. | Istona, J. | Pavlendova, H. (Forest Research Institute, Zvolen (Slovak Republic))
The effect of alkaline air pollutants appears on 98% of the area of forests in Slovakia. Despite a local impact of magnesite air pollutant type is very significant as to the degree and extent of damage. Despite enormous efforts of magnesite plants only a low reduction of dust fallout was reached. While in the years 1978-1979 emission of Mg dust reached 7396.5 tons and emission of SO2 1133.5 tons, in the years 1990-1991 respective figures were 1174.5 tons of Mg dust and 1114 tons of SO2. It means that the amount of emitted SO2 has not changed but the amount of emitted dust has dropped 6.5 times. On the basis of research results the whole attacked territory was divided into four zones of endangerment and there were tested various reclamation and revitalization measures successfully
اظهر المزيد [+] اقل [-]Nutrient concentrations in the foliage of beech (Fagus sylvatica L.) and Norway spruce (Picea abies L. Karst.) plants of a model ecosystem in response to long-term exposure to atmospheric CO2 enrichment and increased N deposition
2002
Landolt, W. | Egli, P. | Pezzotta, D. | Bucher, J. B. (Swiss Federal Research Institute WSL, Birmensdorf (Switzerland))
The biological effects of both elevated CO2 and N deposition on model ecosystem were investigated in the Birmensdorf open-top chamber facility. Each of the 16 chambers was divided into two compartments with a ground area of 3 msub2 and filled with natural unfertilized forest soils from two sites (one acidic, the other calcareous). Elevated CO2 significantly increased O and Zn concentrations in beech leaves and those of Zn in spruce needles on the calcareous soils. Enhanced N deposition also led to a dilution of nutrients and increased N contents
اظهر المزيد [+] اقل [-]Impact of regional pollution load on tree condition and interpretation of assessment methods
2002
Augustaitis, A. (Lithuanian University of Agriculture, Kaunas (Lithuania). Forest Monitoring Laboratory)
Investigation of air pollution impact on tree condition indicates the greatest correlation between pine defoliation and SO2, SO4 and NH4 concentration in the air, NH4 load with precipitation and its pH in the eastern part of Lithuania. In the southern part significant correlation was found between defoliation and SO4 concentration in the air and SO4, NH4 load with precipitation and its pH. No significant correlation was found in the western region of the country, which includes seaside part. Tree age and tree development classes have an essential effect on the correlation significance
اظهر المزيد [+] اقل [-]Elemental composition of lime wood response to atmospheric deposition
2002
Mankovska, B. (Forest Research Institute, Zvolen (Slovak Republic)) | Popierova, D. | Florek, M. | Frontasyeva, V. | Yermakova, L. | Antoni, J.
Instrumental neutron activation analysis was used for determination of element concentration in 10 year old segments of lime wood in extremely polluted area in Central Spis. We found the highest concentrations of Al, As, Au, Br, Cl, K, Na, Rb, Sb and Sm in the oldest 80-90 year old forest. The same elements were determined in atmospheric deposition with moss bio-monitoring technique. In the area of Central Spis we found in comparison with Norwegian limit values exceeded levels for the elements as given similarly for comparison with Magnitogorsk in Ural Mountains
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