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Bioindication of air pollution by epiphytic lichens in forest decline studies in Slovenia
1995
Batic, F. (Ljubljana Univ. (Slovenia). Biotechnical Fac., Agronomy Dept.) | Mayrhofer, H. (Graz Karl-Franzens Univ. (Austria). Botanik Inst.)
First studies of this kind were based on mapping of cover and frequency of crustose, foliose and fructicose epiphytic lichens on trees which were assessed also for the decline symptoms. Since 1985 epiphytic lichen vegetation has been assessed by this methods and results, expressed as a lichen map of Slovenia were used as an air quality indicator for plots of forest die-back inventory. In case studies of forest decline, in collaboration with lichenologist from Graz Univ., Austria, all epiphytic lichen species were mapped in order to obtain better measure of air quality in the area studied. Very polluted and still clean and well preserved forests were investigated. From the material collected and determined a lichen herbarium has been established on the Slovenian Forestry Inst.. Possibilites of further research and use of epiphytic lichens as air quality indicators are discussed.
Afficher plus [+] Moins [-]Air pollution stress in forest-physiological perspective
1995
Bytnerowicz, A. (USDA Forest Service, Riverside (USA))
Mechanisms of air pollution toxicity are very complex and depend on various physiological and biochemical properties of plants. These mechanisms (including formation of free radicals) are still poorly understood. In addition, physiological responses of forest plants to air pollution stress can be modified by various biotic (e.g., insects, pathogens, mycorrhizae associations, genetic variation) and abiotic (e.g., increasing CO2 concentrations, ultraviolet-B radiation, nitrogen desposition, nutrient deficiencies, drought) factors. An example of air pollution effects on forest trees may be responses of ponderosa pine seedlings to elevated concentrations of ozone: various physiological changes in trees (lowered net photosynthesis, altered carbon allocation, deterioration of photosynthetic pigments, etc.) have led to reduced growth and biomass of plants.
Afficher plus [+] Moins [-]Soil and tree disturbances due to forest operations - an unresolved, interdisciplinary issue
1995
Robek, R. (Forestry Inst. of Slovenia, Ljubljana (Slovenia)) | Matthies, D.
In the paper authors review the complexity of the impacts on the forest ecosystem caused by road construction and logging operations and discuss research activities in that field. Interdiciplinary approach is emphasized and research priorities are suggested. The studies are needed where structural parameters of the soils are related to the plant vitality. This will help us understand the forests response on the impact and enable us to develop the practical techniques for soil and stand protection during further actions.
Afficher plus [+] Moins [-]Forestry and society-oriented research on the history of virgin forests and their future needs
1995
Mlinsek, D. (Ljubljana Univ. (Slovenia). Biotechnical Fac., Forestry Dept.)
Giemsa C-banding of the chromosomes in the macrogametophyte of norway spruce
1995
Kohler, B. | Guttenberger, H. (Graz Univ. (Austria). Plant Physiology Inst.) | Borzan, Z. (Zagreb Univ. (Croatia). Forestry Fac.)
Giemsa C-banding method was applied on chromosomes in the female gametophyte tissue of Norway spruce (Picea abies (L.) Karesten). A karyogram of one single tree growing in the Botanical Garden of the University of Graz, Austria, was made by using an image analysis system. All chromosomes (n=12) showed pericentic C-bands. Chromosomes II, V and IX possed intercalary C-bands located at secondary constrictions. Telomeric C-bands appeared in chromosomes II and III on both arms.
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