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Valtera M.,Silva Tarouca Research Institute for Landscape and Ornamental Gardening | Schaetzl R.J.,Michigan State University
Forest Ecology and Management | Year: 2017

Forest ecosystems are known for their capacity to retain and redistribute water. Nevertheless, even in some forested watersheds, prolonged or intense rainfall events often exceed the retention threshold of the system, generating accelerated runoff. Surface microrelief is an important attribute of forest ecosystems that often act to mediate potential runoff. In most natural forests, the soil surface is typically unevenly broken with pit and mound microrelief, formed by both historical and recent tree uprooting events. In managed forests, however, tree uprooting is traditionally seen as undesirable. The systematic repression of this process may lead to gradual loss of microrelief. To date, little attention has been paid to the impacts of the pit-mound microrelief, or its absence, on forest hydrology. Restoration of naturally undulating microrelief in managed forests can help to accentuate water retention and mitigate runoff, while reducing drought stress and reinforcing forest productivity and resilience. This paper summarizes the literature and presents insights on the effects of tree uprooting on the microrelief of forest soils and forest hydrology, focusing on its consequences to water retention, tree water supply, and forest health. Furthermore, we explore the mechanisms and possible consequences of the long-term repression of these processes in intensively managed forests, with implications for forest management and further research. © 2017 Elsevier B.V.

Havlickova K.,Silva Tarouca Research Institute for Landscape and Ornamental Gardening | Suchy J.,Silva Tarouca Research Institute for Landscape and Ornamental Gardening
Renewable and Sustainable Energy Reviews | Year: 2010

This paper deals with modelling the development of plantations for intentional biomass production. The model of plots for the areas of interest consider the following biomass sources: intentionally produced biomass from SRC of fast-growing trees and non-woody energy crops (sorrel, reed grass and triticale). Statistical data for the entire area of interest (NUTS1 size) and data for a part of this area (NUTS3 size - 18% of total area of interest) were used to determine data on the area of arable land and permanent grasslands in the initial year. This paper presents a model of the development of production plots for the period 2008-2030. Yields are calculated of selected energy crops with regard to their growing cycle using so-called triangular method. The core of the algorithm for calculation of growing area of energy crop is an optimalization of processes regarding economic and technical demands for long-term and sustainable production of biomass. © 2010 Elsevier Ltd. All rights reserved.

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.

Samonil P.,Silva Tarouca Research Institute for Landscape and Ornamental Gardening | Kral K.,Silva Tarouca Research Institute for Landscape and Ornamental Gardening | Hort L.,Silva Tarouca Research Institute for Landscape and Ornamental Gardening
Geoderma | Year: 2010

The role of tree uprooting in soil formation was evaluated using an analysis of scientific articles published from 1940 to 2009. The potential for generalizing these published results across a range of regions, forest and soil types was assessed. We focused on the following topics: ecological conditions within pit-mound microsites; the area of pit-mounds in different landscapes; the age of pit-mounds; rotation period; and the effect of tree uprooting on soil properties, including the absence of pit-mound dynamics in forests that have been managed long-term. These topics were analysed on the spatial scales of the pit-mound, forest stand, and landscape. The effect of tree uprooting on soil formation has been particularly studied in northern hardwood forests on Podzols in the region of the Great Lakes (USA, Canada). Fewer studies have been done in Europe, Asia or Australia, and we are not aware of any studies from tropical rain forests and temperate forests in South America or Africa. The ecological characteristics of pit-mound microsites with moister, colder and more stable pit conditions are well known and can be generalized. On the other hand, the proportional area of pit- mounds is highly variable, ranging from 0 to 90% depending on forest history and natural conditions, and therefore has only local validity. The maximum age of pit-mounds is most often 200-500 years, though sometimes pit-mounds can be older than 2000 years. The duration of pit-mounds depends on geologic, geomorphologic and climatic conditions, and thus has regional validity. The rotation period (how often an area equivalent to the entire study area is disturbed) is a synthetic characteristic which is largely similar within specific biomes, and usually is as long as 103 years. However, there is still an open question concerning the heterogeneity of the rotation period on fine spatial scales, especially considering the assumed higher susceptibility of some microsites to disturbances. On fine spatial scales, the effect of tree uprooting on soil formation is relatively well understood. However, the traditional method of approximating the development of pit-mound soil properties by using a linear function is a gross simplification. Faster leaching from pits compared with mounds and currently undisturbed soils is a common phenomenon, and is valid across forest and site types. Under specific site conditions and under specific disturbance regimes, however, this phenomenon may not necessarily be applicable. On the scale of the forest stand, the opinion predominates that pit-mound dynamics inhibit the development of soils. This theory is hardly ever supported with quality data, however, and results from some important studies do not fully reflect this. In managed forests, where there is a long-term absence of pit-mound dynamics, studies have indicated that the stage of soil formation is more advanced compared with naturally disturbed forests. The impact of tree uprooting on the development of soil spatial variability is thus still insufficiently explained. At the landscape scale, there are only few relevant studies dealing with the importance of tree uprooting where authors have demonstrated the significant effect of pit-mounds on erosion-sedimentation processes. © 2010 Elsevier B.V. All rights reserved.

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.

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.

Businsky R.,Silva Tarouca Research Institute for Landscape and Ornamental Gardening
Phyton - Annales Rei Botanicae | Year: 2013

Vietnam shows one of the greatest conifer diversity in Eurasia, and Pinus is the genus with the highest species richness (8 species). There is a great taxonomic confusion or there are only provisional identifications of Pinus species in the relevant literature. In this study Vietnamese populations of pines with controversial identities have been taxonomically reassessed. All taxa are summarised and geographical distribution on the basis of the author's field knowledge of Asian pine species is given. The main results were as follows: 1) the specimens referred commonly to as Pinus kwangtungensis belongs to P. eremitana (SW of the Red River Basin) or to P. wangii (NE of the Red River Basin) with geographically separated P. w. subsp. wangii (in the north of the Ha Giang Province) and P. w. subsp. variifolia (eastwards from the Ha Giang Province); 2) P. merkusii reported in Vietnamese flora refers to the mainland species P. latteri, including the population called "Muong Tip pine" in the western tip of the Nghe An Province; 3) a very limited and isolated population of a two-leaved pine called "Na Hang pine " from the karstic mountains near the boundary of the Tuyen Quang and Bac Can Provinces was identified as P. henryi, which was currently known only from China; 4) the pine recently discovered at the SE tip of the Son La Province near the border with Laos, referred to as P. armandii, was identified as the true P. fenzeliana, currently known only from China. - The true taxa Pinus kwangtungensis (= P. wangii subsp. kwangtungensis) and P. merkusii do not occur in Vietnam or in adjacent regions and should be excluded from accounts of the Vietnamese flora. A determination key to all taxa of the genus Pinus relevant to the flora of Vietnam is given.

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.

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.

Sucharova J.,Silva Tarouca Research Institute for Landscape and Ornamental Gardening
Journal of Analytical Atomic Spectrometry | Year: 2011

An inductively coupled plasma spectrometer (ICP-MS) equipped with a dynamic reaction cell (DRC) was used for determining Se in plant samples. A study was made of the ways of removing polyatomic interferences that affect the determination of the most abundant isotopes of selenium, using CH 4 or, alternatively, NH 3 as a reaction gas. We optimized the efficiency of the bandpass tuning and the cell gas flow rate for suppressing potentially interfering product ions formed by ion-molecule reactions in the dynamic reaction cell of an inductively coupled plasma mass spectrometer. 115In + was selected as an internal standard for determining Se by DRC ICP-MS. We monitored the rate of reaction between 115In + and CH 4 or NH 3, and the product ions created from reactions between In + and CH 4 or NH 3. The trueness of the analytical results was assessed by the use of CRMs for Se in plants. The Se experimental results obtained by DRC ICP-MS and by conventional ICP-MS methods were compared with certified values. The values obtained by DRC ICP-MS at m/z 78 with NH 3 as the reaction gas were in good agreement with all analysed reference materials at an RPq value of 0.75, zero RPa and cell gas flow rate 0.8 mL min -1. The use of ammonia instead of methane was more appropriate for determining Se in plant samples. Higher reaction efficiency was achieved for suppressing the interferences of double charge ions of lanthanides, and, in addition, determining 80Se + with CH 4 as the reaction gas in plant material with a higher Br content, than in the certified reference material NIST Tomato Leaves 1573a (1300 ng g -1 Br), which suffers from strong interference from 1H 79Br +. © 2011 The Royal Society of Chemistry.

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