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Seasonal ultrastructural changes in the cambial zone of beech (Fagus sylvatica) grown at two different altitudes
No full textSeasonal structural changes of cambial cells in mature beech (Fagus sylvatica L.) trees growing at elevations of 400 m a.s.l. (lowland) and 1200 m a.s.l. (mountains) are presented on the basis of light (LM) and electron microscopy (TEM). For LM, samples from trees were collected at weekly intervals and for TEM at two-month intervals from March till September, 2008. LM enabled us to follow the production of new xylem and phloem cells that lasted for 16.5 ± 3.7 weeks at the lowland site and for 10.7 ± 1.3 weeks in the mountains. TEM revealed differences in ultrastructure of cambial cells in the phases of dormancy, reactivation, activity and transition to dormancy. The seasonal patterns of ultrastructural changes in cambial cells were similar at both sites but their timing was different. TEM revealed changes in the fine structure of cambial cells, indicating their activation in spring and the earliest stages of cell divisions and development of new cell walls. When using LM, the onset of cambial activity could be observed one month later, compared with TEM. LM therefore enabled us to follow cambial productivity but not the activity and related cytoplasmic modifications during reactivation
Genetic differentiation of the Western capercaillie highlights the importance of South-eastern Europe for understanding the species phylogeography [Elektronski vir]
No full textWestern capercaillie (Tetrao urogallus L.) is a grouse species of open boreal or high altitude forests of
Eurasia. It is endangered throughout most mountain range habitat areas in Europe (Storch 2007).
Considered to be an umbrella species, Western capercaillie serves as an indicator of sufficiently preserved
structures of old coniferous or mixed forests. Genetic differentiation studies of Western capercaillie in
Eurasia (Duriez et al. 2007, Rodríguez-Muñoz et al. 2007, Segelbacher and Piertney 2007, Segelbacher et
al. 2003, Liukkonen-Anttila et al. 2004) revealed the existence of two main genetically identifiable
lineages: the southern and the boreal lineage. The southern lineage has been discussed as a glacial relict
(Duriez et al. 2007, Rodríguez-Muñoz et al. 2007) and has only been described at southern edges of the
species distribution range in Europe. We addressed the question of genetic differentiation of Western
capercaillie populations across all major habitat areas in the Balkans including Rhodope and Rila
Mountains in Bulgaria, Dinaric Mountains (Slovenia, Croatia, Bosnia and Herzegovina, Montenegro,
Serbia) and Southeast Alps in Slovenia. The contact zone between the two lineages and the resulting
implications for conservation strategies in this so far under-studied area of distribution had not been
determined previously
Strokovne podlage Programa ohranjanja kmetij in podeželja v gorskem in hribovitem svetu z omejenimi možnostmi gospodarjenja
Get PDFTreatment of recovered wood-based panels
No full textDue to the increasing global production of wood based panels (particleboards, fiberboards, and plywood) problems with raw material and difficult treatment of recovered wood based panels after life cycle occur. Inorganic pollutants represent the main problem of raw material while treatment of recovered wood-based composites is aggravated due to the presence of synthetic adhesives. Latter and the release of methane during anaerobic decomposition are reasons for using alternative methods instead of sending these composites to landfills. The most promising methods of recovered wood-based panels treatment are: hydrothermal recycling, re-manufacturing of panels, combustion and pyrolysis, composting, re-use and some other less used methods for processing of new recycled products
Types of ectomycorrhizae on beech seedlings (Fagus sylvatica L.) in rhizotrons
Get PDFNatural processes or human activities affect environmental conditions, as reflected in the structure of the communities and the level of ectomycorrhizalfungi. The aim of the study was to determine the potential impacts of several temperature regimes of air and soil (substrate) on the occurrence and species diversity of ectomycorrhizal fungi in symbiosis and in the substrate. For this purpose, we analyzed the occurrence of types of ectomycorrhizae on beech seedlings in rhizotrons exposed to four different environmental temperature conditions: 1) air 15-25°C, 2) air 15-25°C in combination with cooling of roots for 5°C, 3) elevated air temperature from 30-50°C, and 4) ambiental conditions (air temperature in Ljubljana). Types of ectomycorrhizae were identified with a combined approach of anatomical morphological characterisation and with analysis of molecular markers (ITS1-5.8S rDNA-ITS2 ribosomal region in rDNA). We identified a total of 6 types of ectomycorrhizae on 51 root tips on 40 beech seedlings. The diversity of ectomycorrhizal types was the highest in terms of near-optimal growth conditions of beech. Most similar as far as species diversity of ectomycorrhizal fungi are concerned were the experiments with air temperature of 15-25°C with or without cooling of the root system. The commonest ectomycorrhizal species was Hebeloma sacchariolens, which was also the most commonly seen species in fine roots of dead plants. Selected species of ectomycorrhizal fungi were further substantiated with DGGE method in all analyzed substrate samples
The impact of traffic on the epiphytic lichen species composition
No full textFor the assessment of traffic-originated pollutants input into the environmentand their impact on biocenosis, the passive bioindication was used at eight selected road sections, where mapping of epiphytic lichen flora was implemented according to a German (VDI) method. The mapping of epiphytic lichens implies that lichens can be used in bioindication studies along roads; indeed, at locations with higher traffic density (average daily traffic > 20,000) fewer lichen species were identified in comparison with locations with lower traffic density. At road sections with very high traffic density only epiphytic lichen species most resistant to pollution were recorded, while less resistant but still highly tolerant to nitrogen pollution lichen species were recorded at road sections with moderate traffic density (average daily traffic around 10,000). At those road sections, the lichen species more sensitive to air pollution also begin to occur, which were not recorded at road sections with very high traffic density, not even 100 m away from the roadside
Genetic differentiation of the Western Capercaillie highlights the importance of South-Eastern Europe for understanding the species phylogeography
No full textThe Western Capercaillie (Tetrao urogallus L.) is a grouse species of open boreal or high altitude forests of Eurasia. It is endangered throughout most mountain range habitat areas in Europe. Two major genetically identifiable lineages of Western Capercaillie have been described to date: the southern lineage at the species’ southernmost range of distribution in Europe, and the boreal lineage. We address the question of genetic differentiation of capercaillie populations from the
Rhodope and Rila Mountains in Bulgaria, across the Dinaric Mountains to the Slovenian Alps. The two lineages’ contact zone and resulting conservation strategies in this so-far understudied area of distribution have not been previously determined. The results of analysis of mitochondrial DNA control region sequences of 319 samples from the studied populations show
that Alpine populations were composed exclusively of boreal lineage; Dinaric populations of both, but predominantly (96%) of boreal lineage; and Rhodope-Rila populations predominantly (.90%) of southern lineage individuals. The Bulgarian mountains were identified as the core area of the southern lineage, and the Dinaric Mountains as the western contact zone between both lineages in the Balkans. Bulgarian populations appeared genetically distinct from Alpine and Dinaric populations and exhibited characteristics of a long-term stationary population, suggesting that they should be considered as a glacial relict and probably a distinct subspecies. Although all of the studied populations suffered a decline in the past, the significantly lower level of genetic diversity when compared with the neighbouring Alpine and Bulgarian populations suggests that the isolated Dinaric capercaillie is particularly vulnerable to continuing population decline. The results are discussed in the context of conservation of the species in the Balkans, its principal threats and legal protection status. Potential conservation strategies should consider the existence of the two lineages and their vulnerable Dinaric contact zone and support the specificities of the populations
