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EN
This paper presents the results of studies on the variability of selected features of the morphological structure of Scots pine trees, introduced on the post-mining lands in Piaseczno reclaimed for forestry. The field research was conducted in 2014 in the north-western part of a waste dump, on one-are circular sample plots. These plots were established in three groups, depending on the type of a substrate and the implemented reclamation treatments (1 – the Quaternary loose sands, 2 – mixed sediments of the Quaternary loose sands and the Tertiary Krakowiec clays, 3 – mixed sediments of the Quaternary loose sands and the Tertiary Krakowiec clays after an intensive preplant fertilization). The Scots pine trees introduced on the reclaimed dump displayed various crown structures and growth parameters. The longest and the widest crowns were recorded for the pine trees growing on mixed sediments of sands and clays, whereas the trees growing on loose sands had the smallest diameters at breast height.
EN
The paper presents the results of research on variability in the static bending strength of the “Tabórz” Scots pine wood (Pinus sylvestris L.). The wood samples for examination were obtained from the trunks of 260-year-old Scots pines felled in the “Sosny Taborskie” Nature Reserve. The mean value for all the tested wood samples amounted to 77.3 MPa, whereas for the individual trunks it reached 105.3 MPa, 66.4 MPa and 60.1 MPa, respectively. It is believed that the research results presented here are the first empirical data published concerning the mechanical properties of the wood of the “Tabórz” Scots pine, the trunks of which, due to their high quality, are considered in Europe to be extremely valuable timber.
3
Content available Image analysis in wood testing - selected examples
EN
This paper is a review article which presents examples of application of the image analysis in wood testing. The objective of the paper was to present selected research methods with the use of image analysis used in the research on anatomy and macro-structure of wood carried out in the Department of Forest and Wood Utilization of the Institute of Forest Utilization and Forest Technology of the University of Agriculture in Krakow. In the part concerning research on wood anatomy the following areas of application of the image analysis were indicated: identification of wood species and variability of the selected parameters of the anatomic structure with special attention to coniferous trees. In the part concerning the research on macro-structure of wood, methodology of collection and preparation of wood samples and measurement of the most important properties of the macrostructure was described with the use of the image analysis program. Moreover, the selected areas of practical application of the results of such analysis were indicated.
PL
Niniejsza praca jest artykułem przeglądowym, prezentującym przykłady zastosowania analizy obrazu w badaniach drewna. Celem pracy było przedstawienie wybranych metod badawczych z zastosowaniem analizy obrazu, wykorzystywanych w badaniach anatomii i makrostruktury drewna, prowadzonych w Zakładzie Użytkowania Lasu i Drewna, Instytutu Użytkowania Lasu i Techniki Leśnej Uniwersytetu Rolniczego im. Hugona Kołłątaja w Krakowie. W części dotyczącej badań anatomii drewna wskazano na takie obszary zastosowania analizy obrazu jak: identyfikacja gatunku drewna oraz zmienność wybranych parametrów jego budowy anatomicznej, ze szczególnym uwzględnieniem gatunków iglastych. W części dotyczącej badań cech makrostruktury drewna opisano metodykę pobrania i przygotowania próbek drewna oraz pomiaru najważniejszych cech makrostruktury przy pomocy programu do analizy obrazu. Wskazano także wybrane obszary praktycznego zastosowania wyników takiej analizy.
EN
The paper presents the results of investigations into the variability of certain features of the wood macrostructure, such as the width of the annual ring, the share of late wood, and the relative density of the wood of grand fir, growing in four stands in southern Poland. The trees under investigation were 30-35 years old. The research material consisted of incremental cores sampled from trial trees with the use of a Pressler borer. The examined wood features were analysed in sections, each one comprising five annual rings. The rings were given numbers, sorted in an ascending order from the trunk circumference. The mean values of the analysed features were as follows: the annual ring width – 4.38 mm, the share of late wood - 35.39%, the relative wood density – 0.354g·cm-3. It was established that the wood of grand firs growing on less fertile soils had significantly narrower annual rings and higher wood density than those on more fertile soils.
EN
Investigations were carried out at timber storage sites (depots) on large-sized pine (110 pieces) and beech (130 pieces) wood from three forest districts within the territory of the Regional Directorates of the State Forests (RDSF) of Łódź, Lublin and Kraków. As a result of a comparison of both classification systems, it was proved that in the case of pine wood classified according to EU norms, the shares of the number of pieces and volume in classes B and C decreased, whereas they increased in class D when compared with Polish classification. Analogically, in the case of beech wood, a decrease in the share of the number of pieces and volume in classes A, B and D, and an increase in class C were recorded. Among the most common defects that influence the classification of both sorts of wood, open and burl knots as well as curvatures are recognised, while in the case of beech wood, shakes and galls (disease T stains) are encountered. The results of the classification determined differences in the wood value. According to the pricelists for wood standing in forest districts where the raw wood under investigation originated, it was established that the value of the pine wood classified according to the EU norm decreased by ca. 7.6% when compared with the value estimated using the Polish norm. The value of the beech wood was nearly identical in both cases, which was mainly due to the higher share of wood of class C and lower share of class D upon applying the EU standards, in comparison with the Polish classification system.
PL
W artykule przedstawiono wyniki analizy porównawczej jakości surowca świerkowego pochodzącego z drzewostanów naturalnych (rezerwatowych) i drzewostanów pełniących funkcje gospodarcze. W analizach uwzględniono również wady drewna wpływające na wyniki klasyfikacji badanego surowca oraz częstotliwość ich występowania. Wytypowane do badań drzewostany zlokalizowane były w terenach górskich: w Sudetach i Karpatach. W wyniku przeprowadzonych analiz stwierdzono, że nieznacznie lepsze pod względem jakości surowca drzewnego są w porównaniu z drzewostanami naturalnymi (rezerwatowymi) drzewostany pełniące funkcje gospodarcze.
EN
The aim of this study is to determine the variation in the quality structure of spruce timber and to analyze the frequency of occurrence of trees with defects, including the generic structure of defects in natural stands (forest reserves) and stands serving economic functions. The study was conducted on 20 experimental plots located within the Sudeten and Carpathian Mountains, of which 10 were located in the area of nature reserves or national parks while the other 10 - in the managed stands (table 1). Each experimental plot constituted 5 or 10% of the area of the whole stand, depending on its differentiation. The following tasks were performed on the experimental plots: measurement of the breast-height diameter of each tree with a thickness of at least 7 cm, measurement of the height of each tree, quality assessment of the first section of the tree stem from the base along with its quality-dimensional class or group [Zasady... 2003], recording the types and varieties of wood defects. Analyzing the research material obtained, the stem of each tree growing on an experimental plot underwent simulated division into sections corresponding to the quality-dimensional classes and groups which could theoretically be distinguished over the whole length of a stem up to its top. The starting point was the quality-dimensional class noted in the butt section of the stem (section 1) during the field research. The above tasks included the use of the Radwański tables [Roczniki... 1956], which allowed the determination of the size and volume of each section of the spruce stems on the basis of the breast-height diameter and the tree height; wood defects, noted in field, were also taken into account. The material obtained was divided into 2 groups: data from the reserves and from the managed stands. For the material grouped in this way, juxtapositions were made of the average volumes of individual stem sections in quality-dimensional classes and groups of timber and the percentages of particular timber classes and groups in the two stand types were calculated. The material was also analyzed taking into account the generic structure of defects (percentages of individual trees with particular wood defects in a given group of stands). The next stage consisted in statistical analyses using the U-Mann-Whitney test, examining the significance of differences in the quality-dimensional structure of timber and the share of trees with defects between the two groups of stands. The research showed that trees growing in natural stands (reserves) are characterized by a greater average height, thickness (d1.3 and d1/2) and volume of individual trees as compared with the same characteristics of spruce trees in managed stands (table 2). Also, the average volume of the large-sized timber sections (WA, WB1, WB, WC, WD) of individual trees from natural forests dominated the volume of tree sections in managed stands. Despite that fact, the volume/ha of natural forest stands was lower (355.91 m3/ha) than of managed stands (380.27 m3/ha). By analyzing the quality-dimensional structure of the examined timber it was found that the proportion of higher quality timber classes (WA and WB) prevails in the managed stands, resulting in a lower share of the WC class of timber (fig. 1). Only the share of WB1 class timber prevails in natural stands. The managed stands also showed a larger share of medium-sized timber (groups S1, S2 and S4) as compared to natural forests. The U-Mann-Whitney statistical test, however, did not show statistically significant differences in the timber quality structure between the natural and the managed stands (U = 49.00, Z = -0.0378, p = 0.9698). Subsequently, it was found that the proportion of trees with quality reduced by defects was higher in the natural stands (70.38%) as compared to the managed stands (67.13%). The main defect, decisive for timber quality, were knots (in both groups of stands). The share of trees with that defect was greater in the stands of natural origin (fig. 2). In those stands, there was also a larger share of trees with rot (external and internal rot) and unilateral curvatures. The managed stands demonstrated a share of injuries (overgrown and open ones) as well as bilateral and multilateral curvatures that was higher than in the natural stands. In conclusion, it should be emphasized that in the managed stands within the research area a higher quality of spruce timber as well as higher volume/ha were noted as compared to the natural stands (forest reserves). Stands in forest reserves are generally located at higher altitudes in the mountains or hardly accessible areas; their main purpose are protective functions, they also serve the purposes of research. In the stands situated in forest reserves there was reported, in comparison with the managed stands, a higher incidence of trees with a large number of knots and highly affected by rot. A frequent presence of such defects is inevitable there because this group does not undergo any management cuts that would improve timber quality. Moreover, the presence of rot is due to the advanced age of these stands. At the same time, what is disturbing is a large share of trees with injuries in the managed stands. Given that spruce is very sensitive to mechanical damage of the stem, resulting in rapid development of rot, caution is recommended during forest management work and harvesting in spruce stands.
PL
Przedstawiono wyniki badań dotyczących porównania jakości surowca świerkowego pochodzącego z dwóch zasięgów jego występowania w Polsce (północno-wschodniego i południowo-zachodniego) oraz w obrębie zasięgu południowo-zachodniego z dwu ośrodków - sudeckiego i karpackiego. Porównywano zarówno strukturę jakościowo-wymiarową surowca drzewnego, jak i występowanie wad drewna wpływających na wyniki klasyfikacji. Otrzymane rezultaty nie dostarczyły jednak jednoznacznej odpowiedzi na pytanie: drewno, którego świerka nizinnego czy górskiego jest jakościowo lepsze?
EN
Due to the lack of comprehensive comparative research into the quality of spruce raw material from two ranges of spruce distribution in Poland an attempt to solve this issue was made. In connection with that aim of the research was set to be a comparative analysis of the quality of spruce raw material from centers and ranges of spruce distribution in Poland, and indication of characteristic features and the most important differences. Research covered two natural ranges of Norway spruce distribution in Poland - the south-western range and the north-eastern range. The following measurements works were carried out in the research areas: measurement of the diameter breast high of each tree of the thickness of 7 cm and more; measurements of the height of trees breast high of 7 cm; classification of raw material with the information on grade or quality-dimension group - of the first butt section of a trunk; registration of types and varieties of flaws; sampling from the bottom part of a trunk with the use of Pressler drill from 15 spruces selected by Draudt method from each research area. This research did not explicitly confirm the opinion of higher quality of spruce raw material from south-western range of distribution in comparison to wood from north-eastern range distribution.
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