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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
Afficher plus [+] Moins [-]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
Afficher plus [+] Moins [-]Depositions from precipitation in the forest ecosystem of pedunculate oak and their possible impacts on the stability of the lowland forests in Croatia
2002
Tikvic, I. (University of Zagreb, Zagreb (Croatia). Faculty of Forestry) | Seletkovic, Z. | Sojat, V. | Znidaric, G.
The paper deals with the results of chemical analyses of the precipitation collected with the bulk method in and out of the pedunculate oak forest near Lipovljani in Croatia, for the period 1997-2001. A considerable higher total annual deposition of the majority of analysed determinants has been found in the forest. The results point to the importance and influence of the forest cover on the reception and distribution of dry and wet pollution in the forest ecosystem of pedunculate oak
Afficher plus [+] Moins [-]Effects of big polluters on biodiversity of northern terrestrial ecosystems
2002
Kozlov, M.V. (University of Turku, Turku (Finland). Section of Ecology)
Impacts of big polluters on adjacent ecosystems can be seen as long-term unintentional experiments. Contrary to the common guess, results of these experiments may be used to address basic ecological problems, like diversity - stability and diversity - productivity relationships, as well as evaluate general effects of disturbance on ecosystem structure and functioning. Toxicity of pollutants plays a leading role at early stages of forest decline, while transformation of forests into birch woodlands and industrial barrens is accelerated by positive feedback's acting primarily via changes in microclimate
Afficher plus [+] Moins [-]A global overview of the long-term effects of air pollution on forest trees and ecosystems
2002
Bastrup-Birk, A. (Centre of Forest, Landscape and Planning, Hoersholm (Denmark)) | Kozlov, M. | Thienhoven, M. van
This paper aims to integrate existing information on effects of air pollution on main forest tree species of economic importance, mainly on growth and reproduction. Gaps in knowledge and areas for future research will be identified
Afficher plus [+] Moins [-]Diagnosis of pollution effect on Slovak forest ecosystems
2002
Mankovska, B. (Forest Research Institute, Zvolen (Slovak Republic))
Presented paper based on long-term and systematic research of the negative effect of pollutants and of the content of the elements in particular parts of forest environment (the years 1965/2002) proves of the importance, need and justificatin of the research on given subject. Knowing the elemental composition of pollutants as to its quality and quantity is basic precondition with diagnosing the effect of polluted air on forest environment. For the needs of practice three main pollution deposition types (acid, alkaline and ammonia) and 8 subtypes were established. They represent changes of forest ecosystems caused by different substances from pollutants
Afficher plus [+] Moins [-]Foreign tree species cultivated in the emission damaged area of the ore mountains
2002
Paul, M. (Saxon State Institute for Forestry, Pirna/OT Graupa (Germany). Department of Genetics and Breeding)
The paper presents forest damage in Saxony, silvicultural treatment and the choice of tree species, base of the choice of tree species for areas damaged by air pollutants and solving the problems only on interdisciplinary basis
Afficher plus [+] Moins [-]Change analyses of forest health condition development in Ziar nad Hronom region influenced by aluminium plant
2002
Bucha, T. | Mankovska, B. (Forest Research Institute, Zvolen (Slovak Republic))
Forest health condition was evaluated on 111 terrestrial permanent monitoring plots. Image classification for the whole region was done by using regression equation between data from the terrestrial survey and digital value of original and derived synthetic bands of Landsat TM. It was found that synthetic channels give better result than original bands. The change analysis was carried out by the method of image diffferences in image pairs. Output images were standardized and than reclassified into 6 classes. It was found that difference of vegetation indexes between two years gives better result than simple difference between two independent classified images of forest condition
Afficher plus [+] Moins [-]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
Afficher plus [+] Moins [-]Discussion of the effects of N with and without acidified S on a sitka spruce ecosystem after 5 years treatment
2002
Sheppard, L.J. | (CEH Edinburgh Bush Estate, Edinburgh (United Kingdom)) | Crossley, A. | Ingleby, K. | Carfrae, J. | Harvey, F. | Kennedy, V.
Significant differences in the effects of N alone compared with NS Acid have been found with respect to eutrophication and acidification. N alone had no effect on the pleurocarpous mosses, whereas NS Acid caused their death within 2 years. Both treatments enhanced stem area increment and N alone also doubled fine root growth. By contrast NS Acid treatments increased litterfall in a a dose response fashion
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