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Fine root status and element contents in three stands of Norway spruce in the Krkonose mountains
2002
Godbold, D.L. (University of Wales, Bangor (United Kingdom). School of Agricultural and Forest Sciences) | Fritz, H.W. | Cudlin, P. | Bonifacio, E.
Fine root distribution was estimated in three spruce stands with different stages of forest decline. At all 3 sites in the 0-5 cm layer the density of living fine root mass exceeds the necromass. However, in the deeper soil layer necromass exceeds biomass by a factor of 2-4 at Modry Dul, ca. 3 at Alzbetinka and by more than 8 at Mumlavska Hora. The distribution of root density was reflected in the distribution of root length and the number of root tips in each soil layer for the 3 sites
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 [-]Is microbial population associated to ectomycorrhized roots of Norway spruces in Krkonose National Park influenced by forest decline?
2002
Martinotti, M.G. (University of Piemonte Orientale, Novara (Italy)) | Avidano, L. | Fracchia, L.
Investigations on the bacterial communities associated to ectomycorrhized roots of seedlings from three stands with different degrees of regeneration decline (high, intermediate and low) and from seedlings grown on monoliths obtained from the very same stands have been carried out. The results suggest that forest decline does not influence bacterial biomass associated to seedlings roots but induce a clustering of specific bacterial species adapted to the different degree of forest decline
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 [-]The effect of nitrogen fertilization on fungistatic phenolic compounds in roots of beech (Fagus sylvatica L.) and Norway spruce (Picea abies L. [Karst.])
2002
Tomova, L. | Braun, S. | Fluckiger, W. (Institute for Applied Plant Biology, Schonenbuch, (Switzerland))
The phenolic compounds showed different responses to fertilization. Fine roots of beech showed a significant decrease of (-) epicateching (84-99%) and pecatannol (78-98%) with nitrogen fertilization. Fine roots of fertilized Norway spruce showed decreased concentrations of 4-hydroxyacetophenone (33-48%), p-coumaric acid (44-64%), and pecatannol (36-61%). Concentration of p-hydroxybenzoic acid and protocatechuic acid were significantly higher in no fertilized roots. However in both tree species fertilization had no effect on vanillin and quercetin concentration in fine roots. It is suggested that roots of beech and Norway spruce are more susceptible to attacks of pathogens when they are exposed to impact of nitrogen
اظهر المزيد [+] اقل [-]Chloroplast microsatellite markers monitoring genetic differentiation of Picea Abies [L.] Karst. in response to air and soil pollution
2002
Schubert, R. | Muller-Starck, G. | Metzger, H. G. | Riegel, R. (Technical University of Munich, Freising (Germany). Weilhestephan Center of Life and Food Sciences)
The chloroplast genome has been widely addressed to describe genetic diversity in tree species with regard to phylogeographic studies. In contrast, there is little information on the pattern of genetic differentiation in tolerant and sensitive tree populations, responding to different types of environmental stress. The results demonstrate that chloroplast microsatellites markers are useful tools for elucidating and for testing the pattern of genetic differentiation in stress-exposed populations of Norway spruce, offering to prove the feasibility of marker-aided selection in future
اظهر المزيد [+] اقل [-]Evaluation of Norway spruce forest plantation under air pollution load after the application of a slow-release forest tablet fertilizer Silvamix MG
2002
Sarvas, M. | Tucekova, A. | Seben, V. (Forest Research Institute, Zvolen (Slovak Republic))
Fertilization plays an essential role in forest management on the site being under air pollution load in last years. The soil acidity due to the acid fall-out is markedly worse and at the same time the concentration of calcium, phosphorous, potassium and magnesium are decreasing. The fertilization besides positive influence on height increment could help in adaptation process of plants establishment after transplanting and it can eliminate negative ifluence of anthropogenic conditions of the environmnet
اظهر المزيد [+] اقل [-]Long-term changes of soil chemical parameters in forests of Saxony (Germany)
2002
Raben, G. | Symossek, F. | Katzschner, W. | Gemballa, R. | Karst, H. | Kohler, S. | Nowatzki, O. (Saxon State Institute of Forestry, Pirna (Germany))
Taking into account the results of environmental monitoring in forest ecosystems (European Level I- and II-Programme) showing high degrees of soil acidification and still a widespread exceedance of critical loads by deposited sulphur and nitrogen compounds, the programme of differentiated forest protection liming should continue with site specific doses. On the other hand the programme to restore forest ecosystems with higher stability and to a large extent balanced nutrient cycles has to be carried out in order to minimize internal acid-generating processes
اظهر المزيد [+] اقل [-]Surface liming of immission clear-cuts: benefits and risks
2002
Podrazsky, V. | Ulbrichova, I. (Czech University of Agriculture, Prague (Czech Republic). Faculty of Forestry)
Presented study documents the effects of experimental liming on the forest soils and forest plantations (Norway spruce). Liming was performed in the top part of the Orlicke hory Mts., in the altitude 1100 m. Results documented mutual effects on the forest soil as well as on the newly established Norway spruce plantations. It was evaluated the effect of liming on the soil pH, soil adsorption complex, exchangeable nutrients. Special attention was paid to the nitrogen dynamics and to the plantation growth and nutrition
اظهر المزيد [+] اقل [-]Yellowing of the Norway spruce stands in Central Europe
2002
Sramek, V. | Lomsky, B. (Forestry and Game Management Research Institute, Prague (Czech Republic))
Yellowing of trees with current year needle-class remaining green shows typical symptoms of magnesium deficiency. The chemical analysis proved severe deficiency of magnesium and mild deficiency of calcium in needles and forest soils indeed. This corresponds to the new forest decline as observed in the 1970s and the 1980s in some regions in Germany and France. Other contributing factor breaking out yellowing at that extent at particularly short time is not known. The problem is even increasing, because yellowing has recently appeared also in other mountain localities in Central Europe even though in smaller scale
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