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Suchara I.,Silva Tarouca Research Institute for Landscape and Ornamental Gardening
Water, Air, and Soil Pollution | Year: 2012

Two large-scale national monitoring campaigns investigating changes in spruce bark extract acidity and long-term monitoring of bark acidity along elevation transects have been carried out in the Czech Republic. The investigations have revealed significant average changes in the pH values of bark extracts (4 g: 16 ml) from 2.35 to 2.60 between 1989 and 1995, and from 2.60 to 3.25 between 1995 and 2005. In comparison with 1990, the H+ concentrations in bark extracts had decreased by 10-15% in 1995 and by 70% in 2005. National emissions of acidic compounds were reduced by about 58% (1995) and 62% (2005), and the mean annual H+ deposition was reduced by about 60% (1995) and by about 80% (2005). However, neither inventoried current absolute amounts nor specific regional amounts of emitted acidic pollutants correlated significantly with bark acidity in 1995 and 2005. Bark acidity was not significantly affected by the elevation of the sampling plots or by the average tree defoliation. Along the altitudinal transects, considerably defoliated trees near the top of mountain ridges showed permanently lower bark acidity than trees lower down the mountain slopes. Significant differences in average bark acidity were found between defined mountain, highland and lowland elevation zones. In 2005, the epiphytic lichen Hypogymnia physodes was found at almost all sampling plots, with the exception of the most industrialised areas of two coal basins. The abundance of the lichen correlated significantly and negatively with spruce bark acidity and with total nitrogen and copper concentrations in moss growing at the bark sampling plots in 2005. © Springer Science+Business Media B.V. 2011. Source

Businsky R.,Silva Tarouca Research Institute for Landscape and Ornamental Gardening
Phyton - Annales Rei Botanicae | Year: 2014

Three taxa constituting the Pinus merkusii agg., a group with separate phylogeny that is native to tropical SE Asia, have been heterogeneously classified or adopted in modern literature. This situation has been caused by the incomplete comparison of material and missing collective knowledge from important areas of its natural distribution. An ongoing taxonomic study of Pinus in East Asia has revealed the need to review relevant literature sources and to identify and properly typify all names pertaining to the aggregate to prevent further ambiguities. The three accepted taxa were morphologically compared in detail on the bases of field surveys and representative collections were sampled from six geographic regions representing the most important areas of the group's distribution range. All three of the taxa are accepted at the rank of species: P. merkusii is lectotypified with a designated epitype, P. ustulata is newly elevated from the subspecific rank, and for P. latteri a neotype is selected. The synonyms of the latter species, P. ikedae and P. tonkinensis, are also lectotypified. The different taxonomic concepts adopted by various authors and several published discrepancies are discussed. Source

Velebil J.,Silva Tarouca Research Institute for Landscape and Ornamental Gardening
Preslia | Year: 2012

Sorbus omissa is described as a new hybridogenous triploid (2n = 3x = 51) species belonging to the Sorbus latifolia group. This species is considered to be of hybrid origin, with S. danubialis and S. torminalis being its putative parental species. It is a stenoendemic whitebeam occurring in central Bohemia (Czech Republic) in the vicinity of the towns of Roztoky and Libčice nad Vltavou (Prahazápad district) in the valley of the lower Vltava river, where it grows primarily in oak forests (Viscario-Quercetum). The only two known populations contain approximately 150 individuals. This species differs from other similar Czech species of the S. latifolia group in having broadly elliptical to rhomboidal leaves with very shallowly lobed laminas, predominantly with 9-11 lateral leaf veins on each side, and is orange to orange-red fruit at maturity. Observation, morphological comparison and karyological (chromosome counts, DAPI flow cytometry) methods were used to identify this new species. A character-comparison table and a determination key including all taxa of the S. latifolia agg. endemic in the Czech Republic are provided. An illustration, a photograph and a distribution map of this new species are also presented. Source

Horak J.,Silva Tarouca Research Institute for Landscape and Ornamental Gardening
Urban Forestry and Urban Greening | Year: 2011

Urban secondary forest areas are still not in the focus of studies of forest biodiversity. Beetles (Coleoptera) are one of the key groups for assessing biodiversity. I studied beetle fauna and its response to tree species composition using flying interception traps placed on the trunks of dead and withered trees. This study was carried out in Landek, a forest area in an urban agglomeration of one of the largest central European cities, Ostrava (Czech Republic). My results show that species composition and richness and population densities of beetles in this urban forest area may be rather high. Beech (Fagus sylvatica), as the main tree species present, was more species rich and supported more individuals than admixed tree species (oak, hornbeam and ash). I obtained the same results for a group of obligate saproxylic beetles and two of their guilds (old and rotten dead wood, and wood-decaying fungi and mycelia). The beeches also maintained a higher diversity (or were close to being significantly different) than admixed tree species for several functional groups (fungivores, predators and phloeoxylophages), red-listed beetles and indicators, which prefer close-to-natural forests. Thus, beech trees as the main tree species seem to have the function of large habitat islands, which are more species rich than admixed tree species as smaller ones. The admixed tree species hosted fewer species with lower population densities. Forest managers are often confronted by the opinion that real nature cannot be found in cities. My results may be useful during their search for reasons to maintain biodiversity in urban forest areas. © 2011 Elsevier GmbH. Source

Horak J.,Silva Tarouca Research Institute for Landscape and Ornamental Gardening | Rebl K.,Lesak
Journal of Insect Conservation | Year: 2013

Forests support high concentrations of species and beetles in particular are often used to evaluate forest biodiversity. Ancient pasture woodlands are facing a major decline in Europe mainly due to the abandonment of traditional management and subsequent succession. We studied click beetles (Coleoptera: Elateridae) in one of the largest central-European remnants of pasture woodland in Lány Game Park (Czech Republic) using flight interception traps placed at standing veteran trees. The gradient of sun-exposure, circumference of stem, height and vitality of tree and tree species were studied in relation to the species richness of click beetles and their ecological groups. Total species richness reached nearly one half of the recently documented fauna in the study area and species accumulations showed us that the majority of species were represented. Most species preferred solitary trees in sun-exposed habitats and avoided shaded trees in closed canopies. The same results were obtained for ecological groups, such as saproxylic and non-saproxylic species, functional groups and guilds. Our results showed that the species richness of one of the most ecologically diverse beetle families, click beetles, benefits from a high level of sun exposure. Thus, the long spatial and temporal continuity of sun-exposed veteran trees could be a good predictor for sustainable forest management. © 2012 Springer Science+Business Media B.V. Source

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