Wyniki wyszukiwania - Biblioteka Nauki

1

Zwiazki miedzy wybranymi parametrami korony a cechami makrostruktury i gestoscia drewna daglezji zielonej [Pseudotsuga menziesii var. viridis Franco]

100%

Wasik R.

Sylwan

|

2010

|

tom 154

|

nr 11

783-790

2

Zmiennosc wybranych cech makrostruktury i gestosci drewna daglezji zielonej [Pseudotsuga menziesii var. viridis Franco] na terenie Polski

100%

Wasik R.

|

tom 50

|

nr 178

57-85

3

Analysis of changes in wood structure of Douglas fir [Pseudotsuga menziesii var. viridis Britt.] in Poland

100%

Wasik R.

Zeszyty Naukowe Akademii Rolniczej w Krakowie. Sesja Naukowa

|

2005

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tom 91

463-470

4

Variability of the share of heartwood on the stem cross-section of Douglas fir (Pseudotsuga menziesii var. viridis Franco) in Poland

100%

Wasik R.

Acta Scientiarum Polonorum. Silvarum Colendarum Ratio et Industria Lignaria

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2007

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tom 06

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nr 4

EN

This paper presents the results of investigation into the variability of the share of heartwood on the stem cross-section of Douglas fir in Poland. The research was conducted in Douglas fir stands in the IV and V age classes. The feature was analysed on increment cores taken from the trees at 1.3 m level from the base of the stem, in the N and S direction. The differences of the share of heartwood between Douglas firs of the V and VI age classes as well as between the trees growing in moderate and broken crown closure were not significant. No significant differences occurred between specimens of different vitality, either; however, the trend towards increasing the share of heartwood in weak trees with relation to normal and lush ones was noticeable. No significant correlations between the share of heartwood and crown parameters were noted. Three regions were distinguished in the territory of Poland: the southern and north-western ones, where Douglas firs have a higher share of heartwood on the stem cross-section, and the central-western one, where the share is lower.

PL

W pracy przedstawiono wyniki badań zmienności udziału twardzieli na przekroju poprzecznym strzał daglezji zielonej z terenu Polski. Badania prowadzono w drzewostanach daglezjowych V i VI klasy wieku. Badaną cechę określano na odwiertach pobranych z drzew za pomocą świdra przyrostowego, z wysokości 1,3 m od podstawy pnia, z kierunków N i S. Nie stwierdzono istotnych różnic udziału twardzieli między daglezjami V i VI klasy wieku oraz wzrastających w zwarciu umiarkowanym i przerywanym. Różnice istotne nie wystąpiły również między osobnikami o różnej żywotności, zaznaczyła się jednak tendencja do zwiększania udziału twardzieli u drzew osłabionych w stosunku do normalnie i bujnie rozwiniętych. Nie stwierdzono istotnych korelacji pomiędzy udziałem twardzieli a parametrami koron drzew. Na terenie Polski wyróżniono trzy obszary: południowy i północno-zachodni, gdzie daglezje mają większy udział twardzieli na przekroju poprzecznym strzał, oraz środkowo-zachodni, charakteryzujący się udziałem mniejszym.

5

Zastosowanie analizy dendrochronologicznej do określenia zmienności gęstości drewna na przekroju poprzecznym pnia na przykładzie jodły olbrzymiej (Abies grandis Lindl.)

100%

Wasik R.

|

nr 1[30]

6

Wielkie piekno na malym terenie

75%

Wasik R.

Poznajmy Las

|

2008

|

nr 6

26-27

7

Analiza szerokości przyrostów rocznych oraz gęstości drewna buka zwyczajnego (Fagus sylvatica L.) na wybranych powierzchniach w Beskidzie Niskim

63%

Niedzielska B. , Wasik R.

Problemy Zagospodarowania Ziem Górskich

|

1998

|

tom 44

8

Comparative analysis of the calorific value of giant fir timber (Abies grandis Lindl.) from various stands in southern Poland

63%

Wasik R. , Michalec K.

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nr 3

EN

The paper presents a comparative analysis of wood calorific value of grand fir (Abies grandis Lindl.), originating from four stands of the southern Poland. The research material were the samples, collected from the trunks of 30 trees in each stand. The samples were divided into sections, each containing five annual increments. Then each section was measured: annual ring width and the relative wood density, which was converted to dry wood density, taking the total volumetric shrinkage of 11%. It was assumed that the calorific value of 1 kg dry wood of grand fir is 20.15 MJ. On the basis on the analysis it was found that the average calorific value of 1 m3 of grand fir wood was 8021 MJ. It was shown, that a significantly higher calorific value was obtained by the combustion of 1 m3 wood of giant fir trees, growing on the poorer soil in comparison to the more fertile soils. Statistical analysis also showed that with increasing age of the trees the calorific value of 1 m3 grand fir wood increases significantly.

PL

W pracy przedstawiono analizę porównawczą wartości ciepła spalania drewna jodły olbrzymiej (Abies grandis Lindl.) pochodzącej z czterech drzewostanów Polski południowej. Materiałem badawczym były próbki pobierane w każdym drzewostanie z pni 30 drzew. Próbki dzielono na sekcje zawierające po pięć przyrostów rocznych. Następnie każdej sekcji zmierzono szerokości przyrostów rocznych oraz względną gęstość drewna, którą następnie przeliczono na gęstość bezwzględną, przyjmując całkowity skurcz objętościowy 11%. Założono następnie, że ciepło spalania 1 kg absolutnie suchego drewna jodły olbrzymiej wynosi 20,15 MJ. Na podstawie przeprowadzonych analiz stwierdzono, że średnia wartość ciepła spalania 1 m3 drewna jodły olbrzymiej wynosi 8021 MJ. Wykazano, że istotnie większą wartość ciepła spalania uzyskano by z 1 m3 drewna jodły olbrzymiej wzrastającej na glebie uboższej w porównaniu z glebami żyźniejszymi. Analizy statystyczne wykazały również, że wartość ciepła spalania 1 m3 drewna jodły olbrzymiej istotnie zwiększa się wraz z wiekiem drzew.

9

Zmienność wybranych cech makrostruktury i gęstości drewna dębu czerwonego (Quercus rubra L.) z Polski południowo-wschodniej

63%

Wasik R. , Michalec K.

Sylwan

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2020

|

tom 164

|

nr 10

EN

The aim of the paper was to determine the variability of selected macrostructural features and wood density for northern red oak growing in south−eastern Poland. On 4 study plots, we sampled each tree, taking an increment core from the northern side of the trunk, from the height of 1.3 m. The number of tree rings, width and the share of sapwood was measured. The cores were scanned and then tree ring and latewood widths were measured. The latewood proportion in each ring was calculated. Next, starting from the bark, the cores were divided into sections containing 10 annual rings. The relative wood density was determined for each section, then the density was calculated for entire stem cross−section. The mean sapwood width was 1.5 cm. It included 7 annual rings on average, and its share in the trunk cross−sectional area reached 17%. Younger red oaks (II and III age classes) had a significantly higher share of sapwood compared to older trees (IV and V age classes). The investigated red oaks formed narrow−ring wood with an average width of 2.16 mm. The trees growing on deciduous forest habitat had a more equal tree ring width compared to trees from coniferous forest habitats, where this feature showed also higher variability. The latewood proportion in the studied red oaks was 60% on average. The mean relative wood density was 0.578 g/cm³ and it was slightly higher than the value given for red oaks growing in North America. The calculated absolute density (with an assumed volumetric shrinkage from 12.9 to 13.7%) varied from 0.664 to 0.670 g/cm³. It classifies the investigated wood as moderately heavy. Similar density values are given for native oaks, which allows to assume that the technical quality of the wood of red oaks growing in Poland is similar to native oak species. The wood of trees from deciduous forest habitat showed a significantly higher density and a more equal distribution compared to the trees from coniferous forest sites. The raw material of red oaks obtained from deciduous forest habitats should characterize by a better technical quality of wood in comparison with that obtained from coniferous forest sites.

10

Zmienność wybranych cech morfologicznej budowy drzew daglezji zielonej (Pseudotsuga menziesii var. viridis Franco) w Polsce

63%

Wasik R. , Michalec K.

|

tom 48

EN

This paper presents the results of investigation into the variability of selected features of morphological structure of Douglas fir trees in Poland. The research was carried out in 28 Douglas fir stands, which were at least 80 years old. The mean values of studied features amounted: diameter at breast height — 54.8 cm, height — 32.4 m, bark thickness — 3.9 cm, crown length — 13.6 m, relative crown length — 41.6% and crown width — 5.4 m. The significant variability of studied features was stated, especially large diversity bark thickness and crown width was revealed. Four regions were distinguished in Poland. These regions were characterized by some distinction of the studied features.

11

Analiza zmiennosci wybranych cech drewna buka zwyczajnego [Fagus sylvatica L.] w zachodniej czesci Krainy Karpackiej

63%

Niedzielska B. , Wasik R.

Problemy Zagospodarowania Ziem Górskich

|

2000

|

tom 46

97-108

12

The dynamics of stem necrosis occurrence in mountain stands of varying forest cover index and ground slope

63%

Michalec K. , Wasik R.

|

nr 3

EN

The aim of this study was to analyse the frequency and extent of mechanical damage of tree stems in mountain spruce stands of varying forest cover index and ground slope, without taking into account the technology used in obtaining wood. The study was conducted in 17 spruce stands located in the Sudetes and the Carpathians. In the stands the 1 ha test surfaces were established. The damage on trees with dbh ≥ 18 cm was measured. As a result of the analysis it was found that the most damaged trees grew in the stand with forest cover ratio of 0.7 and 1.0, while taking into account the decline of the area most damage was found in the stands with a slope of 16 to 25°. The study, however, showed no clear relationship between the position of necrosis on tree stems (its size and height) and forest cover and a decrease of the area.

PL

Celem pracy była analiza częstotliwości i rozmiaru uszkodzeń mechanicznych pni drzew w górskich drzewostanach świerkowych, o różnym wskaźniku zadrzewienia i spadku terenu, bez uwzględniania technologii wykorzystywanych przy pozyskaniu drewna. Badania prowadzono w 17 drzewostanach świerkowych zlokalizowanych na terenie Sudetów i Karpat. W drzewostanach zakładano powierzchnie badawcze o wielkości 1 ha. Pomiarowi poddano uszkodzenia występujące na drzewach o pierśnicy ≥ 18 cm. W wyniku przeprowadzonych analiz stwierdzono, że najwięcej uszkodzonych drzew powstało w drzewostanach o wskaźniku zadrzewienia 0,7 i 1,0, natomiast z uwzględnieniem spadku terenu najwięcej uszkodzeń powstało w drzewostanach o nachyleniu od 16 do 25°. Przeprowadzone badania nie wykazały jednak wyraźnych zależności między wielkością i wysokością położenia martwic na pniach drzew a wskaźnikiem zadrzewienia drzewostanu i spadkiem terenu.

13

Variability in static bending strength of the "Taborz" Scots pine wood (Pinus sylvestris L.)

51%

Wasik R. , Michalec K. , Mudryk K.

|

2016

|

tom 59

|

nr 196

14

A comparative analysis of pine and beech wood classification according to Polish and EU norms

51%

Barszcz A. , Michalec K. , Wasik R.

|

nr 193

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.

15

Variability of selected macrostructure features, density and compression strength along the grain of “Tabórz” Scots pine wood (Pinus sylvestris L.)

51%

Wasik R. , Michalec K. , Barszcz A. , Mudryk K.

Drewno. Prace Naukowe. Doniesienia. Komunikaty

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2020

|

tom 63

|

nr 205

16

Jakość surowca świerkowego pochodzącego z drzewostanów naturalnych (rezerwatowych) i drzewostanów pełniących funkcje gospodarcze

51%

Michalec K. , Barszcz A. , Wasik R.

|

nr 189

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. TheU-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 injuriesin 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.

17

Differentiation of selected macrostructural features and the basic wood density on the radius of the stem-cross section of black locust Robinia pseudoacacia L. from southern Poland

51%

Wasik R. , Michalec K. , Gach M.

Sylwan

|

2023

|

tom 167

|

nr 08

18

Zmienność wybranych cech makrostruktury i gęstości drewna świerkowego pochodzącego z drzewostanów gospodarczych i terenów pogórniczych

51%

Michalec K. , Wasik R. , Pajak M. , Sikora F.

Sylwan

|

2020

|

tom 164

|

nr 01

EN

The aim of this work was to analyze the tree−ring width, the share of the latewood as well as the density of wood of trees growing in commercial and degraded stands. The research was carried out in the Brynek Forest District (southern Poland) in 3 commercial stands and in 4 degraded stands. For every study plot fifteen spruces were chosen and increment cores were sampled using the Pressler borer. Next, the surface of the cores was smoothed and the width of the annual rings was measured. Latewood zones were determined and the share of latewood was calculated. It was found that the average and minimum tree−ring width was the same in both commercial and degraded stands, while the maximum values were slightly and insignificantly different. In turn, the average share of latewood was higher in trees from commercial stands, but higher minimum and maximum values were recorded in stands on degraded sites. In this case, the differences turned to be statistically significant. The average density of wood was slightly lower in trees from degraded stands compared to wood from commercial stands (413 vs 418 kg/m³). The minimum and maximum values were also higher in trees from commercial stands. However, this feature did not show a significant difference between analysed groups of stands. We found that despite such significant differences in the terrain formed during the production of zinc and lead ores, the wood of trees growing in these areas hardly shows any differences (except for the share of latewood) in comparison to wood from commercial stands.

19

Kształtowanie się szerokości przyrostów rocznych i wytrzymałości na zginanie statyczne drewna kasztanowców białych (Aesculus hippocastanum L.) w warunkach środowiska miejskiego

51%

Wasik R. , Barszcz A. , Michalec K.

|

tom 16

|

nr 2B[39]

20

Badania nad stanem zdrowotnym swierka Picea abies [L.]Karst. w drzewostanach Gorczanskiego Parku Narodowego

51%

Kowalski T. , Leszczynski K. , Wasik R.

|

tom 26

103-119