Kapak Resmi

Wood Quality of Plantation Grown Azadlrachta Excelsa (Jack) Jacobs from Malaysia

Azadirachta exceIsa is a fast growing tree, with tall and straight clear bole. Six planted A. excelsa trees of three growth rates (dominant, co-dominant and suppressed) under the same site conditions and the same age were sampled at three height levels and three radial positions to provide specim...

Ful tanımlama

Kaydedildi:
Detaylı Bibliyografya
Yazar: Sing Boupha, Lathsami Boupha
Materyal Türü: Tez
Dil:English
English
Baskı/Yayın Bilgisi: 1998
Konular:
Azadirachta - Malaysia
Wood - Research - Malaysia
Online Erişim:http://psasir.upm.edu.my/id/eprint/9966/1/FH_1998_11_A.pdf
Etiketler: Etiketle
Etiket eklenmemiş, İlk siz ekleyin!
id oai:psasir.upm.edu.my:9966
record_format eprints
spelling oai:psasir.upm.edu.my:9966 http://psasir.upm.edu.my/id/eprint/9966/ Wood Quality of Plantation Grown Azadlrachta Excelsa (Jack) Jacobs from Malaysia Sing Boupha, Lathsami Boupha Azadirachta exceIsa is a fast growing tree, with tall and straight clear bole. Six planted A. excelsa trees of three growth rates (dominant, co-dominant and suppressed) under the same site conditions and the same age were sampled at three height levels and three radial positions to provide specimens to investigate among growth-rates and within tree variations of anatomical, physical and mechanical properties. Mean vessel, ray and fibre contents were 18.99%, 19.08% and 62.74% respectively. Mean fibre length was 1.12 mm, fibre diameter 24.17µm, fibre lumen diameter l1.55µm, and fibre wall thickness 6.31µm. Mean specific gravity (SG) was 0.59, green moisture content 96.30%, tangential shrinkage 5.64%, radial shrinkage 2.61 % and volumetric shrinkage of 9.3%. Mean shear parallel to the grain was 13.34 MPa, compression parallel to the grain 41.95 MPa, modulus of elasticity (MOE) 6862 MPa, modulus of rupture (MOR) 83.85 MPa and hardness 3.03 kN. The anatomical, physical and mechanical properties of A. excelsa evaluated in this study were comparable to many of the light hardwood species. Therefore, the tree is suitable for a wide range of utilisation. Between growth-rate variations of all properties analysed showed significant difference. In general, dominant trees have thicker fibre wall, higher specific gravity and strength properties than the co-dominant and suppressed trees. The considerable variations in specific gravity, in strength and in anatomical parameters among" trees, if genetically controlled, offers possibilities for selection of breeding stock from seed or cuttings with desirable wood quality. Within tree variations was more pronounced in radial than in vertical direction, suggesting that diameter growth is an important factor contributing to the variations than the height growth. Samples from the midpoint between the pith and the bark were found to have highest specific gravity and also more dimensionally stable in dimension compared to the outer and inner part. 1998 Thesis NonPeerReviewed application/pdf en http://psasir.upm.edu.my/id/eprint/9966/1/FH_1998_11_A.pdf Sing Boupha, Lathsami Boupha (1998) Wood Quality of Plantation Grown Azadlrachta Excelsa (Jack) Jacobs from Malaysia. PhD thesis, Universiti Putra Malaysia. Azadirachta - Malaysia Wood - Research - Malaysia English
institution UPM IR
collection UPM IR
language English
English
topic Azadirachta - Malaysia
Wood - Research - Malaysia
spellingShingle Azadirachta - Malaysia
Wood - Research - Malaysia
Sing Boupha, Lathsami Boupha
Wood Quality of Plantation Grown Azadlrachta Excelsa (Jack) Jacobs from Malaysia
description Azadirachta exceIsa is a fast growing tree, with tall and straight clear bole. Six planted A. excelsa trees of three growth rates (dominant, co-dominant and suppressed) under the same site conditions and the same age were sampled at three height levels and three radial positions to provide specimens to investigate among growth-rates and within tree variations of anatomical, physical and mechanical properties. Mean vessel, ray and fibre contents were 18.99%, 19.08% and 62.74% respectively. Mean fibre length was 1.12 mm, fibre diameter 24.17µm, fibre lumen diameter l1.55µm, and fibre wall thickness 6.31µm. Mean specific gravity (SG) was 0.59, green moisture content 96.30%, tangential shrinkage 5.64%, radial shrinkage 2.61 % and volumetric shrinkage of 9.3%. Mean shear parallel to the grain was 13.34 MPa, compression parallel to the grain 41.95 MPa, modulus of elasticity (MOE) 6862 MPa, modulus of rupture (MOR) 83.85 MPa and hardness 3.03 kN. The anatomical, physical and mechanical properties of A. excelsa evaluated in this study were comparable to many of the light hardwood species. Therefore, the tree is suitable for a wide range of utilisation. Between growth-rate variations of all properties analysed showed significant difference. In general, dominant trees have thicker fibre wall, higher specific gravity and strength properties than the co-dominant and suppressed trees. The considerable variations in specific gravity, in strength and in anatomical parameters among" trees, if genetically controlled, offers possibilities for selection of breeding stock from seed or cuttings with desirable wood quality. Within tree variations was more pronounced in radial than in vertical direction, suggesting that diameter growth is an important factor contributing to the variations than the height growth. Samples from the midpoint between the pith and the bark were found to have highest specific gravity and also more dimensionally stable in dimension compared to the outer and inner part.
format Thesis
author Sing Boupha, Lathsami Boupha
author_facet Sing Boupha, Lathsami Boupha
author_sort Sing Boupha, Lathsami Boupha
title Wood Quality of Plantation Grown Azadlrachta Excelsa (Jack) Jacobs from Malaysia
title_short Wood Quality of Plantation Grown Azadlrachta Excelsa (Jack) Jacobs from Malaysia
title_full Wood Quality of Plantation Grown Azadlrachta Excelsa (Jack) Jacobs from Malaysia
title_fullStr Wood Quality of Plantation Grown Azadlrachta Excelsa (Jack) Jacobs from Malaysia
title_full_unstemmed Wood Quality of Plantation Grown Azadlrachta Excelsa (Jack) Jacobs from Malaysia
title_sort wood quality of plantation grown azadlrachta excelsa (jack) jacobs from malaysia
publishDate 1998
url http://psasir.upm.edu.my/id/eprint/9966/1/FH_1998_11_A.pdf
_version_ 1819293418580344832
score 13.4562235

Benzer Materyaller