bluuebunny/crossref_metadata_2025 huggingface dataset:
Optimization of thinning technology in beech coppice stands in Crni Vrh region
Authors: Bajic Vojislav , Danilovic Milorad
Published: September 2009

The application of rationalized thinning technology in beech coppice stands was studied. Three basic methods of thinning: schematic, selection and combined method were analyzed. In the framework of each of the above thinning methods, different thinning varieties were designed, differing by the degree of crosscutting, width of gathering lines and their distance. The applied method of felling and crosscutting is the whole tree method or log method, and the form of work organization (1M+1R). The felling and crosscutting are characterized by two key work operations: directed felling and manual collection of the felled wood material. Manual collection is made significantly easier by the correct selection of tree felling direction which in turn affects significantly the rationalization of the entire thinning process.
Trg republike: Dominant pedestrian place in central Belgrade zone
Authors: Galecic Nevenka , Vujkovic Ljiljana
Published: September 2009

The paper analyses historical, compositional and functional values of one of the most frequent open space in central zone of Belgrade - Trg Republike. Based on gathered data from terrain, cartographical and literary data genesis of the space, functionality and composition characteristics were analyzed, as well as degree of the usage. It is concluded that neither degree of functionality nor the compositional value of Trg Republike do not satisfy in full, although the degree of usage is very high, as a result of position in the very center of the town, as well as the important surrounding objects.
The proposition of optimal silvicultural-reclamation operations in untended beech stands of mixed origin
Authors: Krstic Milun
Published: September 2009

The state, quality, spontaneous development and silvicultural demands of untended beech stands of mixed origin were studied, the age of trees in the dominant layer is about 75 years. The analysis of stand development through a 17-year period (1986-2003) included the monitoring of the elements of stand structure: Number of trees, basal area, volume, diameter and volume increment, mean stand diameter, structure, mortality and tree removal from the stand, morphological, biological and technical characteristics of trees and biological differentiation of trees. The adequate silvicultural-reclamation measures are proposed based on the identified stand state.
Ecological approach to the study of medicinal plants: Soil-plant relationship
Authors: Obratov-Petkovic Dragica , Popovic Ivana , Kadovic Ratko , Belanovic Snezana , Miletic Zoran
Published: September 2009

A very important parameter for the utilization of medicinal plants is the quality of active substances. The quality of the plant active substances does not depend only on its physiological potential and condition, but also on the environmental factors. The status of microelements in the soil and the basic ecological indices of plants, as the site indicators, at two localities on Mt. Kosmaj are presented. It was concluded that these relationships are very complex, in most cases identical and in direct correlation with the representation of individual plant species. Medicinal plants were analyzed in the first place because of their potential exploitation.
Definition of optimal structure of white ash juvenile stands
Authors: Stajic Branko
Published: September 2009

Optimal structure of young white ash stands was studied in the region of Majdanpecka Domena. The stands are characterized by poor crown development and a high number of trees. The definition of the optimal stand structure was based on the analysis of causal relationships between crown structure and tree and stand increment. It was concluded that the optimal number of trees on the sample plots should be considerably lower compared to the actual number of trees. This would enable an economic utilization of growth space, forming of more efficient crown assimilation, faster growth and more effective tree and stand dimensions, as well as the greater stand vigor and stability.
The distribution, hosts, epidemiology, impact and control of fungus Mycosphaerella pini E. Rostrup apud Munk in Serbia
Authors: Karadzic Dragan
Published: September 2009

M. pini is one the most widespread and dangerous pathogenic fungi in the plantations of Pinus species in the world. This fungus has been observed on more than fifty Pinus species, and on European Larch, Douglas Fir, Norway Spruce, Serbian Spruce and Sitka Spruce. In Serbia, M. pini caused greatest damage in plantations of Austrian pine (P. nigra Arn). In Serbia both states of the fungus have been observed, i.e. conidiomata and ascostromata. Conidia are far more significant in the infection process. The critical period for infections is May - June. Of the all tested fungicides, the best results have been obtained by copper protectants. In heavily infected plantations of Austrian pine the protections should be carried out in the period when the plantations are 5-20(25) years old.
Study of the effect of climate factors on Austrian pine height increment in the seed orchard on Jelova Gora
Authors: Vukin Marina , Isajev Vasilije
Published: September 2009

Variability of height increment and the most important climate elements were researched in the Austrian pine seed orchard on Jelova Gora during the period 1993-2003. The seed orchard was established in 1991 by the principle of meta-population structure. The comparative analysis of the above elements shows the correlation between height increment, as the element of tree growth, and climate parameters, which is significant for the correction of the previous opinions that Austrian pine does not have a biological predisposition for the full utilization of the high production potentials of beech sites.
Mycoflora diversity in the stands and plantations of poplars in the section Aigeiros
Authors: Keca Nenad
Published: September 2009

The saprophytic and parasitic fungi were inventoried in poplar stands and plantations in Serbia. During the four-year study, the material was collected from different localities in order to assess the density distribution and significance of individual fungal organisms occurring in the plantations on different clones and cultivars, but also in other stands of native poplars in the section Aigeiros.
Beech wood export and import trends in Serbia
Authors: Rankovic Nenad , Glavonjic Branko
Published: September 2009

By the establishment and analysis of the model of beech wood export and export trends in Serbia (by quantity and value), for the period 1988-2002 the regularities of the changes of their magnitude in time were defined. On this basis, the relations of import and export trends were analyzed. Based on the study elements, the potentials of beech sawlog and beech sawnwood export, as well as the potential economic effects, were pointed out.
Impact of stereoide fungi on decomposition of oak wood and possibility of its protection
Authors: Miric Milenko
Published: September 2009

Four stereoide fungi, causers of decay of oak wood, have been investigated as follows: Stereum hirsutum, Chondrostereum purpureum, Stereum rugosum and Xylobolus frustulatus. The field tests have been undertaken in order to determine the influence of the stereoide fungi on the wood of Sessile oak (Quercus petraea) and Austrian oak (Quercus robur). Artificial inoculations with mycelia have been provoked in vital standing trees, as well as in laying trunks. The appearance of dying back symptoms, the rate of mycelia spread through the stem, speed of wound callusing and appearance of fruit bodies or decay symptoms, have been observed. The protection possibility of trunks has been tested as well by using preservatives based on chromo-cupric boron salts, dichlorfluanide and chlorinepyriphos, cupric naphtenates, as well as with antiseptic paste. Microscopically analysis of attacked oak wood has been performed by utilizing of scanning electron (SEM) and standard optical microscope providing normal, fluorescence, polarized and UV light, so that anatomical changes of the wood structure elements influenced by fungal activity have been noted.
Exchangeable cations in some soils of Mt. Stara planina
Authors: Belanovic Snezana , Kosanin Olivera
Published: September 2009

Land use in forest and pasture ecosystems requires the respecting of ecological and economic interactions between the individual components of these ecosystems. The content of nutrition elements in the soil solution depends on soil types, climate conditions and vegetation species, i.e., it is conditioned by their cycling in the ecosystem. This paper studies the cation exchange capacity in pasture and forest soils of Mt. Stara Planina.
Effect of planting density on the development of tree and plantation volume of Populus x euramericana (Dode) Guinier cl. I-214
Authors: Vuckovic Milivoj , Andrasev Sinisa , Roncevic Savo , Bobinac Martin
Published: September 2009

The effect of plantation density on the stem volume development phases of mean trees of Populus x euramericana (Dode) Guinier, cl. I-214 were studied in the test plantation aged 25 years with two different planting densities 4.25x4.25 m (treatment A) and 6.00x6.00 m (treatment B). The modeling of stem volume growth of mean trees enabled the identification of development phases based on biological laws. Different growth dynamics of mean trees of the clone I-214, depending on plantation density, had a clear effect on the beginning and the end of individual phases, i.e. subphases of development, as well as on the diameters, heights and volumes of mean trees at the end of each phase of volume development.
Improving germination of Chionanthus virginicus L. seed by using gibberellic acid (GAZ)
Authors: Grbic Mihailo , Nikolic Aleksandar , Skocajic Dragana , Cukic Matilda , Djunisijevic Danijela
Published: September 2009

The aim of this experiment was to explore effects of gibberellic acid on Chionanthus virginicus L. seed germination. The species has great horticultural values but due to problem in propagation it is rarely used. The seed possesses double dormancy: egzo and endo dormancy. Gibberellin has shown helpful in overcoming endo dormancy which is confirmed with this species. Different concentrations of GA3 had different influence. The lower one has shown stimulative effects while the higher one has shown the inhibitor effects. It is also confirmed that endocarp prevents germination.
Analysis of commercial cost-effectiveness of poplar plantations
Authors: Keca Ljiljana
Published: September 2009

The commercial cost-effectiveness of poplar cultivation and commercial cost-effectiveness of long-rotation (42-year) poplar plantation were analyzed. The aim of the research is, based on analysis of expenses and receipts during the period of 42 years and by applying the method of analysis of the project commercial cost-effectiveness, to show the justification of long rotations in poplar plantations. Modern methods of investment valuation were applied and consequently their practical application in forestry was confirmed.
Characteristics of Armillaria species development and their growth at different temperatures
Authors: Keca Nenad
Published: September 2009

Previous research shows that 5 Armillaria species are identified in forest ecosystems in Serbia. This paper presents the Pegler's key of species identification based on fruiting bodies - mushrooms. Previous reference data from Serbia refer only to the species A. mellea. Because of the insufficient information on the bioecology of individual species in the genus Armillaria we studied the effect of temperature, as one of the most important ecological factors for the development of mycelium and rhisomorphs.
Phyto-gegographycal analysis of Divcibare
Authors: Popovic Ivana , Obratov-Petkovic Dragica
Published: September 2009

The aim of phytogeographical analysis is to determine the plant species origin, genesis and migrations. The study results contribute to the knowledge of phytogeographical classification of the particular regions. Different chorions, by their effects, determine the flora structure and composition. The aim of the floristic research of Divcibare was to identify the diversity of flora in this region, i.e., in a wider sense, the diversity of flora in Serbia. Phytogeographical analysis was based on floristic research. The identified plant species were classified into the corresponding floral elements, area groups and area types. The data on diversity and the degree of representation in the flora of Divcibare were obtained based on the percentage of each area type. It was concluded that the flora of Divcibare has a transitional, Central European-Mediterranean-Pontic character.
Symmetric serpentine marking on forest roads by internal circular curve method
Authors: Stefanovic Bogdan
Published: September 2009

This paper presents a new method of symmetric serpentine marking in constructing forest roads on the terrain itself. This method is based on surveying the elements needed for symmetric serpentine marking on forest roads and on estimating other elements and their marking. By using this method construction errors are reduced as well as the number of attempts of serpentine marking on the terrain itself. In the way, the effects of serpentine marking are increased compared to the ones reached by the method used so far.
Heavy metals in the organic soil layer of beech forests in Serbia
Authors: Kadovic Ratko , Kosanin Olivera , Belanovic Snezana , Knezevic Milan
Published: September 2009

During the last decades, forest ecosystems have been strongly exposed to the effect of different harmful pollutants, especially from the atmosphere. Harmful substances from the air, in addition to the direct effect on forest trees, also deposit in the soil, and have an adverse effect on soil chemistry and pedogenetic processes. The results of previous studies in Serbia (Kadovic, Knezevic, 2002, 2004) show some specificities regarding the accumulation and migration of heavy metals in the soil. The highest concentrations were found in the layers of forest litter and in the surface organo-mineral horizons. This paper presents the results of the study of heavy metal contents (Zn, Mn, Cu, Fe, Cd, Pb, Ni and Cr) in the organic horizon (forest litter) of beech forests in Serbia. The study of the heavy metal content in the organic horizon (forest litter) is very significant primarily in the aim of monitoring the trend of their migration through the soil profile and the effect on the soil properties and genesis. The soil quality in beech forests in Serbia was assessed within the Project ICP Forest, Level I, by the methodology UN/ECE-EC, 2000.
Genetic and no genetic variability of two-year old seedlings of 13 hybrid plane half-sib lines
Authors: Knezevic Radmila , Sijacic-Nikolic Mirjana
Published: September 2009

This paper presents the results of the analysis of variability of 8 analyzed morph metric parameters in two-year old seedlings of 13 half-sib lines at different levels. The recorded genetic and no genetic variability is conditioned by numerous different factors. The important causes of genetic variability are: partial incompatibility of parent trees, partial hybrid sterility, predominant inbreeding, frequent mutations with the growth of parent trees, very abundant gene recombination's, etc. The causes of no genetic seedling variability are: external environmental conditions (soil humidity, conditions of cultivation, sylvotechnical interventions, etc) and the internal or the somatic environment of seedling.
Effect of climate index on diameter increment of 40 Austrian pine half-sib lines
Authors: Vukin Marina , Isajev Vasilije
Published: September 2009

The effects of the climate characters and climate index calculated by Thornthwaite-Mather method on diameter increment of Austrian pine trees in the seedling seed orchard on Jelova Gora was studied in the period from 1996 to 2002. The samples for dendrometric analysis were taken from 498 trees in 40 half-sib lines originating from the best natural sites of this species. A strong correlation was determined between the range of precipitation regime and Thornthwaite-Mather climate index, and the development of current diameter increment. The study results indicate that the diameter increment of Austrian pine increases considerably with the increase of humidity, regardless of the relatively modest demands regarding the site productive characteristics.
Analysis of biological spectrum of Divcibare flora
Authors: Popovic Ivana , Obratov-Petkovic Dragica
Published: September 2009

One of the essential analyses which is performed during the floristic study of a region is the analysis of the biological spectrum. The analysis of the biological spectrum of the flora includes the determination of the type of life form for each taxon described in the flora of the study region. If it is considered that life form is a specific structural-functional response to the environmental effects and the result of the adaptation during the species evolution, it is clear that the basic characteristics of the site are more or less reflected in any life form. This fact is confirmed by the analysis of the biological spectrum of Divcibare flora. The study results are in correlation with the results of the analysis of the biological spectrum of the flora of Serbia and the Balkan Peninsula.
Growth models of black poplar trees, section Aigeiros (Duby)
Authors: Andrasev Sinisa , Vuckovic Milivoj , Roncevic Savo , Bobinac Martin
Published: September 2009

Different courses of tree growth in height and diameter in nursery and plantation, immediately after transplanting, cause the difficulties in adaptation of tree growth models. Tree growth models, which do not include the sudden transitions and specificities of nursery growth and in the first years after planting can show errors in the assessment of the values of current and average increment at the moment of culmination and at the age of maximum increment. This paper proposes the introduction of additional parameters in the models of diameter and height growth, e.g. the values of mean diameter at breast height and mean height immediately after planting. Compared to the models without additional parameters, the precision of diameter and height model is reflected in the lower standard error of regression (se) and in the more accurate assessment of current and average increment at the moment of culmination and at the age of culmination.
Dense poplar plantations as the raw material for the production of energy
Authors: Klasnja Bojana , Orlovic Sasa , Galic Zoran , Pap Predrag , Katanic Marina
Published: September 2009

The higher heating value of wood and bark was determined for several poplar (Populus spp) clones. The study included the juvenile one year old plants of the following clones: P.?euramericana cl. ostia, P. nigra cl.53/86, P. deltoides cl. PE 19/66, P.?euramericana cl. I-214, P. deltoides cl. S6-7 and P.?euramericana cv. robusta. By using FVI which takes into account ash content, wood bulk density, and moisture content, it was determined that poplar wood can be a significant energy raw material, primarily thanks to its short rotation cycle and a very high wood volume increment. Significant differences were determined in the values of wood basic density which affect the higher heating value of the study poplar clones, and consequently the yield (weight) of biomass produced per unit area of dense plantations. This is reflected also on the estimated amount of energy that can be produced by the combustion of biomass of the whole one year old plants.
Possibility of micropropagation of dianthus giganteiformis subsp. Kladovanus (Degen) SÓO by the method of proliferation of lateral shoots
Authors: Markovic Marija , Grbic Mihailo , Sindelic Ana
Published: September 2009

The micropropagation of kladovanus carnation (Dianthus giganteiformis subsp kladovanus) was tested by the lateral shoot proliferation method. Micropropagation was performed on the medium with 1/2 MS mineral solution supplemented with 3% sucrose, 0.8% agar, 50 mg?L-1 mio-inositol, 0.025 mg?L-1 thiamin, 0.125 mg?L-1 nicotinic acid and 0.5 mg?L-1 glycine. The development of lateral shoots was induced on 6-benzyl-aminopurine (BAP) and ?-naphthaleneacetic acid (NAA). The best results were achieved on the medium with 1 mg?L-1 BAP and 0.1 mg?L-1 NAA. Rooting was successful on the medium without hormones, and the percentage of acclimatisation was 83%.
Effect of host plant on gypsy moth diet and biological efficacy of Btk preparations
Authors: Milanovic Slobodan , Tabakovic-Tosic Mara , Markovic Nenad
Published: September 2009

The effect of two host plants, Turkey oak (Quercus cerris L) and black poplar (Populus nigra L) on gypsy moth (Lymantria dispar L) development was researched. The effect of host plant was determined based on the parameters which characterize the diet, growth and efficacy of conversion of ingested food of the third instar caterpillars. Along with the effect on development, the effect of host plant on the efficacy of biological preparation based on the bacterium Bacillus thuringiensis var. kurstaki in gypsy moth caterpillar suppression was also researched. The differences in parameters characterizing the diet, growth, and efficacy of ingested food between experimental groups of caterpillars grown on poplar and Turkey oak leaves are explained by the differences in the chemical composition of the leaves of these tree species. The efficacy of Btk preparation is conditioned by the mechanism and content of different groups of defense substances in the leaves of the applied tree species.
Diversity of MAPs in some plant communities of Stara Planina
Authors: Obratov-Petkovic Dragica , Popovic Ivana , Belanovic Snezana , Perovic Marko , Kosanin Olivera
Published: September 2009

The high floristic diversity of Stara Planina was the starting base for the research of medicinal and aromatic plants (MAPs) in individual forest and meadow communities. The sites Javor and Prelesje, forest community Fagetum moesiacae montanum B. Jov. 1953, pioneer community of birch Betuletum verrucosae s.l. and meadow community Agrostietum vulgaris (capillaris) Pavlovic, Z. 1955, were researched as follows: soil types, floristic composition and structure of the community, percentage of MAPs, as well as the selection of species which, according to the predetermined criteria can be recommended for further exploitation. The study shows that the soil of the forest communities is eutric brown, and meadow soils are dystric and eutric humus-siliceous. The percentage of MAPs in the floristic structure of the study sites in forest and meadow communities is 32.35%. The following species can be recommended for the collection and utilisation: Hypericum perforatum L., Asperula odorata L., Dryopteris filix-mas (L) Schott. Urtica dioica L., Euphorbia amygdaloides L., Prunella grandiflora L. Tanacetum vulgare L., Achillea millefolium L., Rumex acetosa L., Campanula glomerata L., Stachys officinalis (L) Trevis., Plantago lanceolata W. et K., Potentilla erecta (L) Rauchel, Chamaespartium sagittale (L) P. Gibbs. Cynanchum vincetoxicum (L) Pers., Euphrasia stricta Host., Fagus moesiaca (Matt) Liebl. and Fragaria vesca L.
The improvement of the edge screw connection in OSB and conventional particleboard
Authors: Popovic Mladjan , Djiporovic-Momcilovic Milanka , Miljkovic Jovan , Gavrilovic-Grmusa Ivana
Published: September 2009

This work presents the method for improvement of direct screw connection performance in conventional particleboard (PB) and oriented strand board (OSB). It is conceived on adhesive insertion into the pilot hole prior to embedment of the screw. The tests were carried out on the PB and OSB, both presenting interior boards and with the same nominal thickness of 18 mm. Particleboard screws of the 5 mm in diameter were inserted in the edge of the board. Pilot hole diameters were 2,5 mm and 3,0 mm and the depth of embedment was 30 mm for all tests. The chosen PVAc adhesive (type 3) with the addition of wood flour as consolidator in the range from 3-10% was inserted into pilot-hole. Tests were also obtained after consequent reassembly of the screw connection in order to examine the ratio of loss in withdrawal forces in such case. It was found that the insertion of PVAc adhesive into the pilot hole and the addition of wood flour have the positive effects on the screw withdrawal force in the tested boards.
Form of turkey oak tree stems in coppice forests of Fruska Gora
Authors: Bankovic Stanisa , Medarevic Milan , Pantic Damjan
Published: September 2009

The study of tree stem form-form factors and form quotients, and their dependence, and the relation with other volume elements is a necessary precondition for the construction of volume tables by indirect methods, which are increasingly applied. After determining the magnitudes of the above indicators of tree stem form, this paper studies the correlation between normal form quotients and normal form factor, then the correlation between normal form factor and tree diameter and height, as well as the correlation of normal and artificial form factor.
Contribution to the development of the method of forecasting the frequency and duration of "failure" of technical systems
Authors: Vukicevic Milan
Published: September 2009

An active approach to the market means the full adaptation of the production system to the demands of the consumers, and the high profitability. To realize the above, production system should create the conditions for the simulation of the behavior of the system in real conditions. In the opposite the behavior of the system will be highly uncertain because of the disturbance in the system. The simulation of the behavior of the system in real conditions includes the existence of reliable information, obtained based on previous research. A series of such information also includes the information on the production cycle of a series of products. The components of the production cycle are also different disturbances. This paper analyses the failures of the technical system. This fact points to the significance of creating the conditions for forecasting the frequency and duration of the "failure". This paper, based on research of two formatisers, presents the methodology of carrying out the forecasting in real conditions.
Determining the degree of fire retardancy of plywood with thermogravimetry, part I: Beech plywood
Authors: Gavrilovic-Grmusa Ivana , Miljkovic Jovan , Djiporovic-Momcilovic Milanka , Kacarevic-Popovic Zorica
Published: September 2009

The basic motive of this work is the ever more pronounced need for fire-resistant plywood. In this work, beech veneers have been impregnated with solutions of chosen fire retardants, which are diammonium phosphate monoammonium phosphate, sodium acetate, water glass, sodium tetra borate and boric acid. To determine the preliminary level of fire retardancy achieved in veneers before manufacturing of finished plywood, thermo gravimetric (TG) and derivative thermogravimetric (DTG) methods are used. TG and DTG analyses of treated and untreated wood, as well as of fire retardants alone, were performed on a Perkin-Elmer TGS-2 thermo gravimetric equipment. Fire resistance of plywood was tested in accordance with standard test for resistance to the effects of fire and the most efficient fire retardants monoammonium phosphate and sodium tetra borate, had the same results as TG/DTG analyses, which points out the validity of TG methods in predicting success of fire retardants in future products.
The influence of irradiated wood filler on some properties of polypropylene - wood composites
Authors: Djiporovic-Momcilovic Milanka
Published: September 2009

The problem of compatibility between the wood filler and thermoplastic matrix is of essential importance in composite production. Numerous methods have been developed for increasing this compatibility, which is still representing a challenging objective of composite research throughout the world. The research into these methods is primarily directed towards their efficiency from the viewpoint of the composite performance and their economical acceptability. The latter is of particular importance for the composite production in the developing countries with respect to the shortage of the corresponding funds. With this respect, the utilization of ionizing radiation might have considerable advantages. In this research, the beech wood flour was irradiated by a dose of 10 kGy of 60Co gamma rays for purpose of provoking the changes by the ionizing effect. The effects of ionizing radiation upon the properties of wood particles have been examined by IR spectroscopy and by determination of contents of hydroxyl groups in wood by acetylating as an indirect method. All these methods have been expected to reveal the chemical effects of the applied radiation treatment. The irradiated and the control wood flour were used in order to produce the samples of composite with polypropylene. The polypropylene-wood flour (PP-WF) composites were produced with 40% of wood particles having fraction size 0.3 mm. The melt-blended composites were modified with amido-acrylic acid (AMACA) as a new coupling agent synthesized for this propose in amount of 6 wt.% (based on wood filler) and successively with 0.05 wt.% (based on PP) of organic peroxide during mixing step. The composites containing coupling agents showed superior mechanical properties, compared to the untreated one. The highest extent of improvement of tensile was achieved in PP-WFl composites modified with AMACA coupling agent.
Effect of phytohormone balance on shoot multiplication and rooting of the species Dianthus serotinus Waldst. and Kit.
Authors: Markovic Marija , Grbic Mihailo , Skocajic Dragana , Djunisijevic-Bojovic Danijela
Published: September 2009

The effect of different phytohormone concentrations on shoot multiplication and shoot rooting was researched on the species Dianthus serotinus. All nutritive media contained MS mineral solution, 3% sucrose, 0.8% agar, 100 mg?L-1 mioinositol, 0.05 mg?L-1 thiamin, 0.25 mg?L-1 nicotinic acid and 1 mg?L-1 glycine. For lateral shoot proliferation, the basic medium was supplemented with BAP (6-benzyl-aminopurine) in concentrations 0.1-2 mg?L-1 and NAA (?-naphthalene-acetic acid) in concentrations 0.1-1 mg?L-1. The best results were achieved on the medium with 0.5 mg?L-1 BAP and NAA. Rooting was most successful (73%) on the medium with 0.5 mg?L-1 NAA.
Metcalfa pruinosa (Say) (Homoptera: Auchenorrhyncha) anew harmful species for entomofauna of Serbia
Authors: Mihajlovic Ljubodrag
Published: September 2009

In the early autumn 2006, a Nonarctic species of cicadas Metcalfa pruinosa (Say) (Auchenorrhyncha: Flatidae) was identified in Belgrade (Kosutnjak). In Europe, this species was identified for the first time in Italy in 1979. In Slovenia, it was identified in 1990 in west Istria, and in 2001 in the neighbourhood of Ljubljana. In the park forest Kosutnjak (Belgrade) mass occurrence of M. pruinosa was recorded in the area of about 5 ha. The larvae developed on woody species in the genera: Acer, Aesculus, Gleditchia Robinia, Ailanthus, Populus, Platanus, Prunus, Pyrus, Ulmus, Tilia, Cornus Fraxinus, Quercus and Thuja, sto is konstatovano based on damages of larvae while numerous adults were found on trees and branches of the same plants.
Relation between consumption and import of wooden windows in France
Authors: Oblak Leon , Glavonjic Branko , Rankovic Nenad , Petrovic Slavica
Published: September 2009

The paper presents the results from the research about the relation between consumption and import of wooden windows in France. Apart from this, regional direction of import as well as the analysis of trends in consumption and import of wooden windows in France have also been presented. Researches were performed during the period from 1995 to 2005.
Properties of Hungarian oak(quercus conferta Kit.) wood from the Hilandar Monastery forest
Authors: Popovic Zdravko , Todorovic Nebojsa
Published: September 2009

This paper presents the study results of the basic physical and strength properties of Hungarian oak (Quercus conferta Kit.) wood from the Kakovo Monastery forests of Hilandar Monastery in Greece. Wood properties were analyzed in detail, as an indispensable proof of wood quality and its use for joinery, interiors and wooden floors. The basic physical properties of wood (moisture content at the time of tree felling, density and volume porosity) and the basic strength properties (compressive strength, bending strength and module of elasticity) were researched. The results are presented in Tables and in Diagrams with statistical parameters and compared to the literature data. The correlation of the study properties of wood was also analyzed.
Classification of trees and the effects of thinning in the artificially established spruce stand in the area of Sokolina-Kotor Varos
Authors: Govedar Zoran
Published: September 2009

The classifications of trees are mainly based on descriptive (attributive) characters and they have a great significance in thinning. In forestry practice (tree marking for felling, forest inventory, etc) in the Republic of Srpska, the most frequently applied classifications are silvicultural-technical (UT) and technical classification of trees, which are based on the knowledge of tree species, stem diameter and stem quality. In IUFRO classification, based on the silvicultural role of trees, and in UT classification, the trees are classified in three categories. The knowledge and application of these classifications is especially significant in the management of artificially established stands. Economic losses in spruce plantations occur because of untimely tending, especially thinning, which has multiple adverse effects on tree quality. The aim of this paper is to point out the application and the relation of UT and IUFRO classifications, as well as the effect of thinning on tree quality structure in both classifications. The research was performed in a 29-years-old spruce plantation established in the belt of mixed forests of beech and fir. The silvicultural-technical and IUFRO classifications were performed and compared in the aim of their application in different thinning treatments (high thinning of light and moderate weight and mixed thinning of moderate weight). Taking into account the state of spruce plantations in the Republic of Srpska, the effect of thinning on stand quality structure was researched and UT classification of trees applied in practice was compared with IUFRO classification.
Chrysomyxa pirolata G. Wint in Rabenh: New parasitic fungus on the cones and seeds of spruce
Authors: Karadzic Dragan
Published: September 2009

The new spruce disease known as "spruce cone rust" was discovered for the first time in Serbia and Montenegro. The fungus was detected in spruce forests only in the mountains regions (Kopaonik, Zlatar, Durmitor). This rust periodically damages the cones in localised forest areas and can be a serious problem. Usually seeds are not formed in diseased cones, and even when they are produced, malformation and resinosis of the cones hinder seed dispersal or extraction. Those seeds that are formed tend to weigh less and have poor germination. As this disease is a serious problem, care must be taken to prevent the spread of the disease to the new uninfected regions.
Structure and silvicultural demands of some narrow-leaved ash stands in the area of the Special Nature Reserve "Gornje Podunavlje"
Authors: Bobinac Martin , Andrasev Sinisa
Published: September 2009

The structure and silvicultural demands of two narrow-leaved ash stands of different origin and age was studied in the Special Nature Reserve "Gornje Podunavlje", in the area protected against floods. The elements of growth and structure in the 38-year-old natural stand in the area of previous wet depressions (dg=24,0 cm, dg20%=33,4 cm, hL=26,1 m, hg20%=27,65 m, N=745 kom?ha-1, G=33,81 m2?ha-1, V=433,3 m3?ha-1), and in the 74-year-old artificial stand on the site of the forest Fraxineto-Ulmetum effusae Slav. 1952 (dg=48,8 cm, dg20%=63,9 cm, hL=35,5 m, hg20%=36,7 m, N=288 kom?ha-1, G=53,86 m2?ha-1, V=842,30 m3?ha-1) point to very high production effects. The diameter distribution of trees is characterised by slight skewness and low kurtosis, and the height distribution of trees is characterised by left skewness. 154 future trees per hectare were selected in the 38-yearold stand, and in the twice older stand with the same initial selection criterion, the number of future trees per hectare was 82. The stands were treated by selection thinning of moderate weight (25% per G), i.e. low thinning based on qd=0.83-0.85. Thinning volume amounted to 109.8 m3?ha-1 in 38-year-old stand, and 207.4 m3?ha-1 in the 74-year-old stand.
Natural regeneration of beech in mixed stands of beech and fir with spruce (Piceo-Abieti-Fagetum) in the virgin forest "Perucica"
Authors: Govedar Zoran , Stanivukovic Zoran
Published: September 2009

Natural regeneration of beech in mixed stands of beech and fir was researched in the virgin forest Perucica, e.g. the basic elements of stand structure with special reference to beech regeneration characteristics, and the regeneration process in the conditions of broken stand canopy. The analysis included the stand development stages in he virgin forest based on the elements of structure, as well as the silvigenetic phases on a transect 10?100 m. The characteristics of beech regeneration (abundance, height, crown size, length of apical and lateral shoots) were measured on the selected regeneration areas (initial regeneration gaps). The silvigenetic phases on the transect and the interdependence of beech regeneration characteristics were assessed based on regeneration characteristics, ways of occurrence and spatial distribution of the young growth.
Amorpha fruticosa L. on wet sites in Belgrade
Authors: Radulovic Stojanka , Skocajic Dragana , Bjedov Ivana , Djunisijevic-Bojovic Danijela
Published: September 2009

Amorpha fruticosa is in many countries, and also in Serbia, one of the most dangerous invasive species. The detection of mechanisms which inhibit the spreading of Amorpha population would be of great significance for finding the adequate measures of biological control. In this sense, first of all it is necessary, inter alia, to determine Amorpha ecological and coenological characteristics. The vegetation studies of wet sites in Belgrade were compared. The study results indicate that Amorpha is present in forest communities, from the lowest elevations at the timber line to the highest elevations, where the periods of underground and flood waters are the shortest, or where they are absent. Amorpha forms thick brushland on meadows with different water regimes and in forest plantations of different canopy closure. If it is regularly removed by felling, Amorpha does not endanger the structure and the floristic diversity of meadow communities. Amorpha is absent or rare in forest plantations of the densest canopy, as well as in the communities which belong, or once belonged, to the alliance Magnocaricion Br.-Bl.
Comparative analyses of water soaking and thickness swelling of particleboard versus different test methods
Authors: Djiporovic-Momcilovic Milanka , Popovic Mladjan , Gavrilovic-Grmusa Ivana , Miljkovic Jovan
Published: September 2009

In regard to its hygroscopic properties, particleboard is dimensionally unstable material when exposed to water or in the atmosphere of high level of humidity. Since today several different standardized methods for determination of thickness swelling exist, the aim of this study was focused on comparison of different testing methods. In this aim, three different methods for determination of water soaking and thickness swelling were compared, two of which were defined by national standard SRPS D.C8.104 and one was defined by European standard EN 317. The results of testing of both properties have shown no significant difference between the EN method based on 50?50 mm test pieces and the SRPS method based on test pieces of 100?100 mm format, suggesting that these two methods can be used alternatively. On the other hand, the results obtained by the SRPS method utilizing the 25?25 mm test pieces, differed significantly from both previous methods. The results were lower for both water soaking and thickness swelling regardless of panel thickness.
Phytocoenological characteristics of beech forests on Manjaca
Authors: Eremija Sasa
Published: September 2009

This paper deals with vegetation in series of sample plots put in the aim to define ecological-vegetational units within forest management unit 'Dubicka gora' and to make basis and scope of future forest management. Research encompassed montane beech forest of Iliyian region (Fagetum montanum illyricum, Fuk. et Stef., 1958) and its more mesic type, forest of beech and Acer obtusatum (Aceri obtusati-Fagetum, Fuk. et Stef., 1963). On the basis of floristic composition and site conditions in the community Fagetum montanum illyricum, four subcommunities were set apart: typicum, aceretosum, drymetosum and geranietosum.
Host plant effect on the activity of digestive enzymes of the gypsy moth caterpillars
Authors: Milanovic Slobodan , Lazarevic Jelica , Mrdakovic Marija , Vlahovic Milena , Miletic Zoran
Published: September 2009

Insect growth and development depend on nutritive value and secondary metabolite content of their host plants. This influence may be exerted through changing the activity of digestive enzymes which further affects efficiency of conversion of ingested food. This paper represents the results of investigation of feeding effects on the leaves of three oak species (Quercus cerris, Q. robur and Q. petraea) on growth, development and digestive enzyme activities of the 4th instar gypsy moth larvae (Lymantria dispar L.). Compared to larvae fed on Q. cerris and Q. robur leaves, larvae fed on Q. petrea exhibited the lowest body mass, midgut protein content and specific protease activity. Specific amylase activity was significantly reduced in the midguts of larvae fed on Q. robur while host plant did not affect larval duration upon molting into the 4th instar. Concomitant chemical analyses of leaves given to the 2nd and 4th instar larvae was carried out in order to explain the obtained results.
The content of heavy metals in the leaves of Hypericum perforatum L. on serpentinite soils in Serbia
Authors: Obratov-Petkovic Dragica , Bjedov Ivana , Belanovic Snezana
Published: September 2009

St John's wort is one of the best known and used medicinal plants. The demands for St John's wort in Serbia is still supplied by the collection of native plants. Therefore it was necessary to examine the concentration of heavy metals in the soil and in plant material on serpentinites and to assess the potential safe harvesting and further utilisation of this plant species. The research was performed on three serpentinite sites in Serbia: Zlatibor, Divcibare and Goc. The main soil types were determined and the contents of 7 chemical elements were analyzed in the soil and in the plant material. It was determined that the soils of all three localities had increased concentrations of nickel, chromium and manganese. The St John's wort plant material (leaves) showed the increased concentrations of iron, nickel and chromium. It was concluded that St John's wort was a tolerant species regarding the heavy metal content, and it was recommended to avoid its harvesting on the investigated localities.
Air pollution effects on the percentage of stomata in the leaves of tested species of horse chestnut and birch in Banja Luka conditions
Authors: Oljaca Rodoljub , Govedar Zoran , Hrkic Zoran
Published: September 2009

The aim of this paper is the determination of air pollution influence on the percentage of stomata in tested woody species, horse chestnut and birch, under examined Banja Luka air pollution conditions. Two locations in Banja Luka town were examined, with different air pollution degrees: the first location is a hostel for students, with the minimal or absent air pollution; the second location is the west transit, with high air pollution due to a high number of motor cars which pass by the west transit. The air pollution difference between these two locations is very marked, and the objective of the examination was to assess how the indicated locations, which have different life conditions for the tested woody species, impact the physiological processes such as transpiration and photosynthesis. The study species react differently when the percentage of stomata and air pollution are compared.
Comparative investigation of durability of chairs made of beach and Paulownia tomentosa
Authors: Skakic Dusan , Dzincic Igor
Published: September 2009

The result of parallel investigation of chair durability, which has been made in two different wood species (beach and Paulwonia tomentosa) has been presented in this paper. Static and dynamic loads has highest values in seating furniture, and that is the reason why chair has been chosen to bee representative for testing new species, which could be used in furniture production in Serbia. A shown results indicates on possibility that this species can be used only for production furniture which wont bee imposed with heavy loads during exploitation.
Grouping and analysis of chair quality and their basic elements
Authors: Skakic Dusan , Dzincic Igor
Published: September 2009

Both the scientific experience and the engineering practice indicate that the decision making processes in the course of solving complex designing problems require an analysis of a great number of different construction variants. These types of decision-making processes are time consuming and do not always result in the selection of an optimal solution. That is why the methods of numerical optimization are applied in a wide range of technical sciences to assist in the selection of the best solution. The first step in solving the problem by using the Finite element method is to determine the type of chair earmarked for modeling, and to determine the dimensions of the chair elements.
Heterocyclic Analogs of Thioflavones: Synthesis and NMR Spectroscopic Investigations
Authors: Fuchs Ferdinand C. , Eller Gernot A. , Holzer Wolfgang
Published: September 2009

The synthesis of several hitherto unknown heterocyclic ring systems derived from thioflavone is described. Coupling of various o-haloheteroarenecarbonyl chlorides with phenylacetylene gives 1-(o-haloheteroaryl)-3-phenylprop-2-yn-1-ones, which were treated with NaSH in refluxing ethanol to yield the corresponding bi- and tricyclic annelated 2-phenylthiopyran-4-ones. Detailed NMR spectroscopic investigations of the ring systems and their precursors are presented.
Fusion of a Short HA2-Derived Peptide Sequence to Cell-Penetrating Peptides Improves Cytosolic Uptake, but Enhances Cytotoxic Activity
Authors: Neundorf Ines , Rennert Robert , Hoyer Jan , Schramm Franziska , Löbner Kristin , Kitanovic Igor , Wölfl Stefan
Published: September 2009

Cell-penetrating peptides (CPP) have become a widely used tool for efficient cargo delivery into cells. However, one limiting fact is their uptake by endocytosis causing the enclosure of the CPP-cargo construct within endosomes. One often used method to enhance the outflow into the cytosol is the fusion of endosome-disruptive peptide or protein sequences to CPP. But, until now, no studies exist investigating the effects of the fusion peptide to the cellular distribution, structural arrangements and cytotoxic behaviour of the CPP. In this study, we attached a short modified sequence of hemagglutinin subunit HA2 to different CPP and analysed the biologic activity of the new designed peptides. Interestingly, we observed an increased cytosolic distribution but also highly toxic activities in the micromolar range against several cell lines. Structural analysis revealed that attachment of the fusion peptide had profound implications on the whole conformation of the peptide, which might be responsible for membrane interaction and endosome disruption.