1721 research outputs found
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Trace elements and nitrogen in naturally growing moss Hypnum cupressiforme in urban and peri-urban forests
No full textWe monitored trace metals and nitrogen using naturally growing moss Hypnum cupressiforme Hedw. in urban and peri-urban forests of the City Municipality of Ljubljana. The aim of this study was to explore the differences in atmospheric deposition of trace metals and nitrogen between urban and peri-urban forests. Samples were collected at a total of 44 sites in urban forests (forests within the motorway ring road) and peri-urban forests (forests outside the motorway ring road). Mosses collected in urban forests showed increased trace metal concentrations compared to samples collected from peri-urban forests. Higher values were significant for As, Cr, Cu, Hg, Mo, Ni, Pb, Sb, Tl and V. Within the motorway ring road, the notable differences in element concentrations between the two urban forests were significant for Cr, Ni and Mo. Factor analysis showed three groups of elements, highlighting the contribution of traffic emissions, individual heating appliances and the resuspension of contaminated soils and dust as the main sources of trace elements in urban forests
Predstavitev strokovnih osnov za pripravo dopolnitev in sprememb Pravilnika o določitvi provenienčnih območij (Ur. l. RS 72/2003, 58/2012): ekspertiza
Full text linkLight response of Fagus sylvatica L. and Abies alba Mill. in different categories of forest edge % Vertical abundance in two silvicultural systems
Full text linkIn managed Dinaric montane fir (Abies alba Mill.) and European beech (Fagus sylvatica L.) forests, the light response of young beech and fir in gap microsites was studied during three consecutive growing periods (2009, 2010, and 2011) under controlled environmental conditions in stands of single-tree and irregular shelterwood silvicultural system. According to maximal quantum yield, the different response between species in microsite light categories was evidenced for silver fir on microsites with predominating diffuse light and for beech on microsites with predominating direct light, respectively. Abundance and change of share in microsite light categories was compared over different elevation belts on comparable sites between two silvicultural systems. The share of forest edge area was bigger in the irregular shelterwood system. Change in width of forest edge (20, 30 and 40 m) did not affect the proportion and share of the microsite in both regions of different silvicultural system. Separation of microsite areas between both silvicultural systems, evident in lower elevation belts was not evident in the most conflict and highest elevation zone, while the absolute values of all categories above 700 m in both systems were almost identical, indicating the same, small-scale irregular shelterwood system, known also as the freestyle silvicultural approach
Missing Rings in Pinus halepensis – The Missing Link to Relate the Tree-Ring Record to Extreme Climatic Events
No full textClimate predictions for the Mediterranean Basin include increased temperatures, decreased precipitation, and increased frequency of extreme climatic events (ECE). These conditions are associated with decreased tree growth and increased vulnerability to pests and diseases. The anatomy of tree rings responds to these environmental conditions. Quantitatively, the width of a tree ring is largely determined by the rate and duration of cell division by the vascular cambium. In the Mediterranean climate, this division may occur throughout almost the entire year. Alternatively, cell division may cease during relatively cool and dry winters, only to resume in the same calendar year with milder temperatures and increased availability of water. Under particularly adverse conditions, no xylem may be produced in parts of the stem, resulting in a missing ring (MR). A dendrochronological network of Pinus halepensis was used to determine the relationship of MR to ECE. The network consisted of 113 sites, 1,509 trees, 2,593 cores, and 225,428 tree rings throughout the distribution range of the species. A total of 4,150 MR were identified. Binomial logistic regression analysis determined that MR frequency increased with increased cambial age. Spatial analysis indicated that the geographic areas of south-eastern Spain and northern Algeria contained the greatest frequency of MR. Dendroclimatic regression analysis indicated a non-linear relationship of MR to total monthly precipitation and mean temperature. MR are strongly associated with the combination of monthly mean temperature from previous October till current February and total precipitation from previous September till current May. They are likely to occur with total precipitation lower than 50 mm and temperatures higher than 5°C. This conclusion is global and can be applied to every site across the distribution area. Rather than simply being a complication for dendrochronology, MR formation is a fundamental response of trees to adverse environmental conditions. The demonstrated relationship of MR formation to ECE across this dendrochronological network in the Mediterranean basin shows the potential of MR analysis to reconstruct the history of past climatic extremes and to predict future forest dynamics in a changing climate
Publishing characteristics in the field of wood value chain and their influence on the assessment of scientific fields in the research evaluation policy - literature overview
No full textThis article presents an overview of bibliometric research in the scientific fields of forestry, wood and paper sciences and highlights the characteristics of publishing in these areas, particularly those that affect the results of the evaluation process and, consequently, the development of these fields. Articles published in scholarly journals are considered important for the development of the scientific field and professional terminology, therefore the review focuses mainly on the specifics in the area of scientific publishing. Although forestry, wood and paper science comprise a single wood value chain, publications mainly cover only the forestry as a result of the interdisciplinary areas, different science classification schemes, narrow research areas, their role in the society. Research work under study focuses mainly on the publications indexed by citation databases WoS and Scopus. Some studies also present the findings on the level of individual institutions or countries. Publication of scientific papers in the field of forestry has an important impact on further development and continuation of journals in this field; especially in less common languages. An important part of articles in these fields is published in the journals which are not classified as forestry-associated indicating interdisciplinarity of the fields, cooperation between authors from different areas, as well as the impact of the evaluation policy on publishing patterns
Forest and wood: idea, invention, innovation (in forestry, wood technology and paper industry): book of abstracts of the Scientific Meeting Forest and Wood, Ljubljana, May 12th, 2016
No full textSuitability evaluation of beech sawdust as reinforcement component in the preparation of thermoplastic biocomposites
No full textBeech sawdust was used as reinforcing component for the preparation of biocomposites with polyoxymethylene – POM and
polylactic acid – PLA as polymer matrix. Materials with different portions of sawdust, e.g. 5, 10 and 15 wt. %, were prepared
by using extrusion and injection techniques. Their mechanical (E modulus, flexural and tensile strength and strain) as well as
thermal (melting point, glass transition) properties were determined. The results indicate that sawdust acts as reinforcement
of the composites in the case of flexural stress and also tensile strength by POM matrix. Addition of sawdust to POM and PLA
increases maximal temperature of biocomposite utilization. The main advantage of new materials is low density. Despite their
brittleness they are convenient, low-cost alternatives to composites reinforced with glass fibres
Short reviews on the genetics and breeding of introduced to Europe forest tree species
No full textMonograph represents short reviews on the genetics and breeding of introduced to Europe forest tree species. The management of tree species non-native to European geographical regions has a long tradition within forestry management practice. Their introduction to Europe (initially focused on growing tree species) dates back to the 18th century when enormous demands were being made on natural resources to sustain the on-going industrialization of Europe. Today issues of biomass production and C sequestration as well as the question of whether these species could increase the adaptive capacity of forests to long-term climate change patterns have fueled a growing interest in non-native tree species in Europe