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Light response of Fagus sylvatica L. and Abies alba Mill. in different categories of forest edge % Vertical abundance in two silvicultural systems
In 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
Trace elements and nitrogen in naturally growing moss Hypnum cupressiforme in urban and peri-urban forests
We 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
Promotion activities of wood industry in Slovenia and in Croatia
Wood industry is among the most important industrial sectors in Slovenia and Croatia. In both countries, wood sector is a part of the national strategy plans and one of the industrial branches considered national economy boosters. But media coverage of wood industry and furniture manufacturing in Slovenia, as well as in Croatia, is far behind the promotion enjoyed by other industrial branches. This paper will give the current situation in promotional activities of wood sector in Slovenian and Croatian media and demonstrate the existing differences among given countries. Also, it will present some ideas on improving this situation according to media share of other highly profiled industrial branches in some southeastern European countries
Short reviews on the genetics and breeding of introduced to Europe forest tree species
Monograph 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
Towards a common methodology for developing logistic tree mortality models based on ring-width data
Tree mortality is a key process shaping forest dynamics. Thus, there is a growing need for indicators of the likelihood of tree death. During the last decades, an increasing number of tree-ring based studies have aimed to derive growth-mortality functions, mostly using logistic models. The results of these studies, however, are difficult to compare and synthesize due to the diversity of approaches used for the sampling strategy (number and characteristics of ‘alive’ and ‘death’ observations), the type of explanatory growth variables included (level, trend, etc.), and the length of the time-window (number of years preceding the alive/death observation) that maximized the discrimination ability of each growth variable.
Here, we assess the implications of key methodological decisions when developing tree-ring based growth-mortality relationships using logistic mixed-effects regression models. As examples we use published tree-ring datasets from Abies alba (13 different sites), Nothofagus dombeyi (one site) and Quercus petraea (one site). Our approach is based on a constant sampling size and aims at (1) assessing the dependency of growth-mortality relationships on the statistical sampling scheme used; (2) determining the type of explanatory growth variables that should be considered; and (3) identifying the best length of the time window used to calculate them.
The performance of tree-ring based mortality models was reasonably high for all three species (Area Under the receiving operator characteristics Curve: AUC > 0.7). Growth level variables were the most important predictors of mortality probability for two species (A. alba, N. dombeyi), while growth-trend variables need to be considered for Q. petraea. In addition, the length of the time window used to calculate each growth variable was highly uncertain and depended on the sampling scheme, as some growth-mortality relationships varied with tree age.
The present study accounts for the main sampling-related biases to determine reliable species-specific growth-mortality relationships. Our results highlight the importance of using a sampling strategy that is consistent with the research question. Moving towards a common methodology for developing reliable growth-mortality relationships is an important step towards improving our understanding of tree mortality across species and its representation in dynamic vegetation models
The state and development of competencies of employees in wood based production
The great changes in business environment, rapid technological development and different approaches to work execution demand
from employees in industry, including woodworking, to constantly develop their capabilities and widen their knowledge.
Education and training are key parts of development of each employee, through which he can gain new knowledge. It is the
key to ensuring their competencies for the job, which in turn leads to greater competitiveness of the companies. The objective
of the research was to assess the level of competencies for different profiles of employees in wood industry production and to
determine the effect of systematic training on the reduction of deficits in competencies. We have established that the biggest
deficits in competencies prior to training were in the fields of development, quality management and control, use of computer
tools and programming and management of CNC technologies. It can be concluded that the state of competencies of production
workers in wood industry is good. Particularly notable is the positive effect of systematic training on the improvement of their
competencies, as there was a significant progress of almost all competencies (by 51.8% on average)
Structure and function of intra-annual density fluctuations
Tree rings are natural archives of climate and environmental information with a yearly resolution. Indeed, wood anatomical, chemical, and other properties of tree rings are a synthesis of several intrinsic and external factors, and their interaction during tree growth. In particular, Intra-Annual Density Fluctuations (IADFs) can be considered as tree-ring anomalies that can be used to better understand tree growth and to reconstruct past climate conditions with intra-annual resolution. However, the ecophysiological processes behind IADF formation, as well as their functional impact, remain unclear. Are IADFs resulting from a prompt adjustment to fluctuations in environmental conditions to avoid stressful conditions and/or to take advantage from favorable conditions? In this paper we discuss: (1) the influence of climatic factors on the formation of IADFs; (2) the occurrence of IADFs in different species and environments; (3) the potential of new approaches to study IADFs and identify their triggering factors. Our final aim is to underscore the advantages offered by network analyses of data and the importance of high-resolution measurements to gain insight into IADFs formation processes and their relations with climatic conditions, including extreme weather events