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Wyświetlanie 1-4 z 4
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
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:
Parametry techniczne młodocianego i dojrzałego drewna sosny zwyczajnej (Pinus sylvestris L.)
Technical parameters of juvenile and mature wood in Scots pine (Pinus sylvestris L.)
Autorzy:
Tomczak, A.
Jelonek, T.
Powiązania:
https://bibliotekanauki.pl/articles/1008693.pdf
Data publikacji:
2012
Wydawca:
Polskie Towarzystwo Leśne
Tematy:
lesnictwo
uzytkowanie lasu
sosna zwyczajna
Pinus sylvestris
drewno sosnowe
drewno mlodociane
drewno dojrzale
parametry techniczne
wytrzymalosc na sciskanie wzdluz wlokien
wytrzymalosc na zginanie statyczne
wspolczynnik jakosci wytrzymalosciowej
basic density
compression strength along the grain
static bending strength
coefficient of quality of strength
Opis:
The study compares selected technical parameters of juvenile and mature wood from different stem sections of Scots pine trees, i.e. breast height diameter, mid−length of the section between breast height and the base of live crown and from the base of live crown. Statistically significant differences were found mainly in relation to mature wood, which indicates that juvenile wood in terms of technical quality is a more homogeneous zone.
Źródło:
Sylwan; 2012, 156, 09; 695-702
0039-7660
Pojawia się w:
Sylwan
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Właściwości drewna sosny zwyczajnej (Pinus sylvestris L.) pochodzącej z gruntów porolnych
Properties of wood of Scots pine [Pinus sylvestris L.] growing on former farmlands
Autorzy:
Jelonek, T.
Pazdrowski, W.
Arasimowicz-Jelonek, M.
Tomczak, A.
Powiązania:
https://bibliotekanauki.pl/articles/1009458.pdf
Data publikacji:
2010
Wydawca:
Polskie Towarzystwo Leśne
Tematy:
lesnictwo
grunty porolne
drzewa lesne
sosna zwyczajna
Pinus sylvestris
drewno sosnowe
jakosc
gestosc drewna
wlasciwosci mechaniczne
wytrzymalosc na sciskanie wzdluz wlokien
zginanie statyczne
wzmocnienie desorpcyjne
scots pine
wood quality
basic density
former farmland
juvenile wood
mature wood
desorption strengthening
Opis:
Analyses were conducted on wood from twelve Scots pines from northern Poland, aged 102 to 110 years, growing on former farmland and on forest grounds. The study was an attempt to determine basic density of wood, compressive strength along the grain, bending strength of absolutely dry wood and wood with moisture content above saturation point. Desorption strengthening was determined for analyzed strength properties of wood. Wood properties were determined in terms of juvenile and mature wood zones. Generally pines growing on former farmlands were characterized by wood with higher density and slightly lower strength than pines growing on typical forest soils. Conducted investigations indicate varied structure and properties of wood tissue formed in pines growing on former farmlands, which is different from that of typical forest soils.
Źródło:
Sylwan; 2010, 154, 05; 299-311
0039-7660
Pojawia się w:
Sylwan
Dostawca treści:
Biblioteka Nauki
Artykuł
    Wyświetlanie 1-4 z 4

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