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Wyświetlanie 1-5 z 5
Tytuł:
Porównanie wybranych właściwości fizycznych drewna młodocianego i dojrzałego sosny zwyczajnej (Pinus sylvestris L.) z drzewostanów rębnych
Comparison of selected physical properties of the juvenile and mature wood of Scots pine [Pinus sylvestris L.] from mature stands
Autorzy:
Tomczak, A.
Jelonek, T.
Zoń, L.
Powiązania:
https://bibliotekanauki.pl/articles/1009416.pdf
Data publikacji:
2010
Wydawca:
Polskie Towarzystwo Leśne
Tematy:
lesnictwo
drzewostany rebne
drzewa lesne
sosna zwyczajna
Pinus sylvestris
drewno dojrzale
drewno mlodociane
wlasciwosci fizyczne
gestosc drewna
gestosc umowna
kurczliwosc
juvenile wood
mature wood
basic density
shrinkage
scots pine
Opis:
The paper presents results of a comparative analysis of basic density and shrinkage of juvenile and mature wood of Scots pine (Pinus sylvestris L.). Mature wood turned to exhibit higher density and shrinkage. Differences are dependent on the location of a sample at the stem profile. Properties of juvenile wood exhibit higher variability in comparison to those of mature wood, especially in relation to shrinkage.
Źródło:
Sylwan; 2010, 154, 12; 809-817
0039-7660
Pojawia się w:
Sylwan
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Zmienność gęstości umownej drewna sosny zwyczajnej (Pinus sylvestris L.) w zależności od wybranych czynników
Variability of conventional wood density of Scots pine (Pinus sylvestris L.) depending on the selected factors
Autorzy:
Witkowska, J.
Lachowicz, H.
Powiązania:
https://bibliotekanauki.pl/articles/993205.pdf
Data publikacji:
2013
Wydawca:
Polskie Towarzystwo Leśne
Tematy:
lesnictwo
drzewa lesne
sosna zwyczajna
Pinus sylvestris
drewno sosnowe
gestosc drewna
gestosc umowna
czynniki siedliska
polozenie geograficzne
typy siedliskowe lasu
wiek drzewostanu
gestosc na wysokosci piersnicy
gestosc w polowie dlugosci grubizny
gestosc w gornym koncu grubizny
scots pine
conventional wood density
forest habitat type
poland
Opis:
Paper presents analysis of differences in conventional wood density of Scots pine measured at breast height regarding the geographical location of stands, forest habitat type, stand age and associated parameters such as density in the mid−length of the stem, density in the upper end of the stem and diameter at breast height. To investigate the impact of these factors, an analysis of covariance was used in accordance with two models specifically developed for this purpose. We found dependence of conventional wood density on the type of forest habitat and geographical location of the stand. The highest density was detected in dry coniferous forests, while the smallest in fresh mixed coniferous forests. Scots pine wood from Zielona Góra Forest (western Poland) characterised with the highest density, while from the Knyszyn Primeval Forest (eastern Poland)− with the lowest.
Źródło:
Sylwan; 2013, 157, 05; 336-347
0039-7660
Pojawia się w:
Sylwan
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Promieniowa zmienność właściwości drewna sosny zwyczajnej (Pinus sylvestris L.) wyrosłej na gruntach porolnych
Radial variation in the wood properties of Scots pine (Pinus sylvestris L.) grown on former agricultural soil
Autorzy:
Tomczak, A.
Jelonek, T.
Powiązania:
https://bibliotekanauki.pl/articles/1339968.pdf
Data publikacji:
2013
Wydawca:
Instytut Badawczy Leśnictwa
Tematy:
lesnictwo
drzewa lesne
sosna zwyczajna
Pinus sylvestris
drewno sosnowe
gestosc drewna
gestosc umowna
wytrzymalosc na sciskanie wzdluz wlokien
wytrzymalosc na zginanie statyczne
zmiennosc cech
czynniki siedliska
grunty porolne
basic density
static bending strength
compressive strength along fibers
Opis:
The soil of former farmland greatly differs from forest soil, and significantly influences tree growth and development compared with other site factors. The effect may also be reflected indirectly in radial variability of wood. This study compared radial variation of wood density, compressive strength along the grain and static bending strength of wood of Scots pine trees growing on former farmland and forest soils. The analyses were conducted in eight mature pine stands. On the basis of the stand description, four stands were classified as growing on forest soil (L) and four as growing on former farmland soil (P). A total of 24 model trees were selected, twelve on each soil type. Analyses of wood properties were conducted along four axes from the cross sectional radius of the treesat breast height. Our analyses showed that radial variation in wood properties of Scots pine (from selected locations in Poland) growing on former farmland is similar to the variation among the control trees growing on forest soils. In both groups of trees, the lowest density and the lowest strength were in the pith (juvenile) zone. Wood with the highest density and greatest strength was located in the central part of the radius. Wood of Scots pine trees growing on former farmland soils in comparison to that of trees growing on forest soil was characterised by a statistically lower basic density, lower compressive strength along the grain and static bending strength.
Źródło:
Leśne Prace Badawcze; 2013, 74, 2; 171-177
1732-9442
2082-8926
Pojawia się w:
Leśne Prace Badawcze
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Wzmocnienie desorpcyjne jako podstawa oceny jakości drewna dębu szypułkowego (Quercus robur L.) i dębu burgundzkiego (Quercus cerris L.)
Desorption strengthening as a basis for the assessment of wood quality of pedunculate oak (Quercus robur L.) and Turkey oak (Quercus cerris L.)
Autorzy:
Szymański, M.
Szykowny, T.
Pazdrowski, W.
Nawrot, M.
Powiązania:
https://bibliotekanauki.pl/articles/994476.pdf
Data publikacji:
2013
Wydawca:
Polskie Towarzystwo Leśne
Tematy:
drzewa lesne
dab szypulkowy
Quercus robur
dab burgundzki
Quercus cerris
drewno debowe
jakosc
gestosc drewna
gestosc umowna
wytrzymalosc na sciskanie wzdluz wlokien
wzmocnienie desorpcyjne
conventional wood density
compressive strength along the grain
basic strength
desorption strengthening
wood quality
Opis:
The analysis was conducted on the wood of two 100−year−old oak species that grew in the riparian forest conditions. The aim of the study was to determine the effect of tree species on conventional wood density, compressive strength along the grain with a moisture content of 12% and above 30% and desorption strengthening. It was found that wood of both oak species differed in density, compressive strength along the grain and desorption strengthening. These differences should be taken into account in the processing and use of timber harvested in the prescribed cuts.
Źródło:
Sylwan; 2013, 157, 11; 811-816
0039-7660
Pojawia się w:
Sylwan
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Związki między wybranymi cechami drzewa a niektórymi właściwościami drewna młodocianego sosny zwyczajnej (Pinus sylvestris L.)
Relationships between selected tree characteristics and the properties of juvenile wood in Scots pine (Pinus sylvestris L.)
Autorzy:
Tomczak, A.
Powiązania:
https://bibliotekanauki.pl/articles/1312952.pdf
Data publikacji:
2014
Wydawca:
Instytut Badawczy Leśnictwa
Tematy:
lesnictwo
drzewa lesne
sosna zwyczajna
Pinus sylvestris
cechy morfologiczne
wysokosc drzew
piersnice drzew
wysokosc osadzenia pierwszej zywej galezi
srednica korony
dlugosc korony
drewno sosnowe
drewno mlodociane
gestosc drewna
gestosc umowna
wytrzymalosc na sciskanie wzdluz wlokien
wytrzymalosc na zginanie statyczne
modul elastycznosci przy zginaniu
korelacja cech
basic density
strength perpendicular to grain
bending strength
modulus of elasticity
breast height
diameter
tree height
crown length
crown diameter
Opis:
The aim of this study was to determine relationships between selected properties of juvenile wood and characteristics of the stem and crown of Scots pine. Analyses were conducted in northern Poland in eight mature pine monocultures. Nine trees were selected in each experimental site and their stems were divided into five sections. The centers of the sections were established at a height of 1.3 m from the tree base and at points corresponding to 20, 40, 60 and 80% tree height. Samples were taken from these locations, and these samples were prepared for analyses of basic density, compressive strength along the grain and static bending, as well as the modulus of elasticity during bending. The mean height of the investigated group of trees was 26.0 m with an average diameter breast high of 33.6 cm. The mean crown depth was 7.8 m and crown diameter was 3.6 m, and the mean basic density (Qu) of juvenile pine wood was 416 kg/m3. The average compressive strength along the grain (CS) was determined to be 22.3 MPa, while static bending strength (BS) was 45.8 MPa. The recorded modulus of elasticity (MOE) was 4726 MPa. Both in general terms and when dividing stems into sections, the wood properties correlated with tree characteristics to various degrees. All indexes were negative indicating that trees of greater dimensions produce juvenile wood of inferior quality. Properties of juvenile wood formed during various periods of tree life were mostly related to diameter breast high and crown depth. They were also correlated with tree height, but only to a limited extent. In contrast, properties of wood from the middle stem sections were significantly correlated with crown diameter.
Źródło:
Leśne Prace Badawcze; 2014, 75, 3; 237-244
1732-9442
2082-8926
Pojawia się w:
Leśne Prace Badawcze
Dostawca treści:
Biblioteka Nauki
Artykuł
    Wyświetlanie 1-5 z 5

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