Shima Ramezani; Mohammad Talaeipoor; Misam Aliabadi; Asghar Tabeai; Behzad Bazyar
Abstract
Samples were prepared from the native poplar species (Populus alba) grown in Mehnan, a region in Bojnourd at the ages 5 and 25 and the anatomical, biometrical and chemical characteristics of the samples sections in three directions (cross section, radial and tangential) of the tree were measured. ...
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Samples were prepared from the native poplar species (Populus alba) grown in Mehnan, a region in Bojnourd at the ages 5 and 25 and the anatomical, biometrical and chemical characteristics of the samples sections in three directions (cross section, radial and tangential) of the tree were measured. Dioxan and Klason lignin were measured. Structural similarities in vascular cavities or impacted vessels in the form of binary, tripple or tetraploidy groups in juvenile and mature wood was observed primarily in radial direction. Fiber length and cell wall thickness variation in the juvenile and mature wood was significantly different and as the age of the tree increases, such difference is more significant. This point need to be considered by cellulose industries. As the age of the tree increase and the wood matures, significant change in vessel size in samples from 5 or 25 years old trees was not detected. The result showed that the older wood contains lower content of extractive and lignin and higher content of cellulose
Physics and anatomy
Ahmad Jahan latibari; Fardad Golbabaei; Mohammad reza Amini
Abstract
Pinus teada, which was planted in Pelembera region, shows promising both in growth rate and adaptability. Even though the fiber geometry of P. teada wood in its native growth region is excellent, but for utilization of this wood in pulping, the knowledge of its technological characteristics especially ...
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Pinus teada, which was planted in Pelembera region, shows promising both in growth rate and adaptability. Even though the fiber geometry of P. teada wood in its native growth region is excellent, but for utilization of this wood in pulping, the knowledge of its technological characteristics especially fiber geometry is required.Two trees of this species were randomly selected from Pelembera forests plantation in Gilan and after felling were cut in smaller bolts and transferred to wood &paper research laboratory, research institute of forests and rangelands. Five cross-sections with the thickness of 15 cm were cut from each tree and the cross-sections were used for selection of samples. Fiber geometry measurement samples were prepared from every five annual rings and from each sample, springwood (early wood) and summer wood (late wood) sample were cut separately. Preparations of fiber geometry samples were according to procedure developed by Franklin (1954) and from each sample the dimension of 30 complete and unbroken trachieds was measured.Trachied length, diameter, cell wall thickness and lumen diameter was measured for different elevation in tree and different growth rings in cross-section.Dimension of 3,00 trachieds were measured totally.Average trachied length, diameter, lumen diameter and cell wall thickness of early wood were measured at 3.65mm, 38.97 mm, 28.94 mm and 3.72 mm respectively. Related values for late wood is as follow: trachied length 3.84mm; diameter, 35.54 /lm; lumen diameter, 22.96 mm; and cell wall thickness, 6.29 mn. Average annual growths were measured at 5.66 mm and late wood percentage at 24.13. Felting, flexibility and runkel coefficients were calculated at 97.96, 73.48, and 26.74 respectively. The result of this study indicates that all measured properties increases with increasing the height of tree and from center (pith) toward outer regions (bark). However all the measured values decreased at highest as well as outer locations.Statistical analysis indicated that the difference in measured properties at different heights of trees from center to the bark is significantly different at 1% level.
