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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
显示更多 [+] 显示较少 [-]Forests health status as the result of environmental impacts and forestry interventions
2002
Hocevar, M. | Mavsar, R. | Kovac, M. (Slovenian Forestry Institute, Ljubljana (Slovenia))
The analysis of the latest results along with the change analysis reveals that the conditions of Slovenia's forest are considerably stable and that the process of decline has not progressed with the intensity, that had been predicted in the early eighties. Quite favourable conditions are due to prompt actions (selection and sanitary cutting) in the field
显示更多 [+] 显示较少 [-]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
显示更多 [+] 显示较少 [-]Mechanised site preparation and restoration of degraded site
2002
Ulbrichova, I. | Podrazsky, V. (Czech University of Agriculture, Prague (Czech Republic). Faculty of Forestry)
It was performed the study of the humus forms, quantity and pedochemical characteristics, further the study of plantation growth, and the dynamics in the period of 1994-1999. Negative impacts of the bulldozing were documented, acidification in the period 1994-1999 and the ameliorative role of the birch stand as well
显示更多 [+] 显示较少 [-]Natural regeneration of Norway spruce ecosystems in the Krkonose mountains: conditions and constraints
2002
Cudlin, P. | (Academy of Sciences of Czech Republic, Ceske Budejovice (Czech Republic). Institute of Landscape Ecology) | Chmelikova, E. | Falta, V. | Gronsky, R. | Sera, B. | Polak, T.
Results on germination, growth and mortality of Norway spruce seedlings during period 1994-2000 in various types of soil cover were summarized and evaluated. The years 1992 and 1995 were recorded as high seed production years, while the year 2000 is considered as the low seed production year. In 1999 natural seedlings from various soil covers were examined for lateral root and root tip development. The results of germination and surviving of Norway spruce seedlings are discussed in relationship with the stage of the decline of Norway spruce ecosystems
显示更多 [+] 显示较少 [-]Evaluation of environmental impact on Pinus mugo Turra as bioindicator in Subalpine belt of Julian Alps in Slovenia
2002
Batic, F. (University of Ljubljana, Ljubljana (Slovenia). Biotechnical Faculty) | Mavsar, R. | Rozman, A. | Sircelj, H. | Simoncic, P. | Turk, B.
Determination of the streses operating on a forest ecosystem demands the use of several bioindication methods. Air quality indicators were assessed from an inventory of forest decline based on the assessment of tree crowns and lichens. Photosynthetic pigments, ascorbic acid and major macro nutrients were studied in mountain pine (Pinus mugo Yurra) needles as indicators of physiological and biochemical stress. Analyses were carried out at selected forest plots and transects in predominantly unpolluted areas within Triglav National Park, Julian Alps, Slovenia. It was assumed that air pollutant input in forest ecosystems is of two kind, e.g. local from the air pollutin sources in the valleys on the North-West part of tha national park and transboundary source at high altitudes
显示更多 [+] 显示较少 [-]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
显示更多 [+] 显示较少 [-]The contributing role of SO2 and drought in forest decline of Austrian pine in coastal Croatia
2002
Diminic, D. (University of Zagreb, Zagreb (Croatia). Faculty of Forestry) | Hrsovec, B. | Potocic, N.
This case study confirms the role of air pollution impact on forest susceptibility to other abiotic and biotic detrimental factors. It is however very important to take into account numerous contributing factors in order to interpret or predict the degree of damage correctly
显示更多 [+] 显示较少 [-]Spatial variability of some topsoil character in a declining forest site (Krkonose National Park, Czech Republic)
2002
Zanini, E. | Caimi, A. | Santoni, S. | Bonifacio, E. (DIVAPRA-Chimica Agraria, Grugliasco (Italy))
45 sites were selected and sampled on the transects and according to the first results of the spatial analysis, 15 more sites were added where useful for the optimal interpolation. Topsoils were sampled including both the soil organic horizons and the more superficial mineral horizon, frequently E, if reached. The depth of the organic horizons, the grass cover, ranked by its hydrophilic character, related to the incipient hydromorphy visible where Norway spruce is more declining, and the Norway spruce health status were systematically recorded
显示更多 [+] 显示较少 [-]Macro and microscopic effects of polluted seasprays on Pinus halepensis needles in El Saler Natural Park (Valencia, Eastern Spain)
2002
Calatayud, V. (Fundacion CEAM, Valencia (Spain)) | Della Rocca, G. | Paoletti, E. | Sanz, M. J.
Coastal forest decline due to seasprays has been reported from all continents, both on broadleaves and conifers. The main cause has been identified in the presence of surfactants. Sea winds transport these substances to the leaves, where they are absorbed via cuticula and stomata producing indirect and also direct damage. The scope of this work is the macroscopic and microscopic assessment of the long term effects of polluted seasprays on Aleppo pines in natural conditions from the Saler coastline (Eastern Spain) inwards. Surfactants may be involved in the damage to Aleppo pine in El Saler as more severe episodes of damage have been observed in the last decade
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