Modeling of radial variations of wood properties in naturally regenerated trees of Betula platyphylla grown in Selenge, Mongolia

Abstract

Wood properties, such as annual ring width, wood fiber length, vessel element length, basic density, air-dry density, dynamic Young’s modulus, modulus of elasticity (MOE), modulus of rupture (MOR), absorbed energy in impact bending, compressive strength parallel to grain, and shearing strength, were investigated for wood from 10 naturally regenerated trees of Betula platyphylla Sukaczev in Mandal, Selenge, Mongolia. Mixed-effects models were used to evaluate the radial variations in the wood properties. The mean values of wood properties obtained in the present study were in almost the same range, with a few exceptions, as those reported by other researchers for other Betula species. The radial variations of wood properties in B. platyphylla were well-fitted to a nonlinear mixed-effects model (logarithmic formula); all examined wood properties increased from the pith and then became constant toward the bark side. The wood properties significantly differed between the core and outer wood. Basic density, air-dry density, and dynamic Young’s modulus were significantly correlated with MOE, MOR, and compressive strength. It is concluded that when the wood of B. platyphylla is utilized as raw materials for solid wood products, the differences between the core wood and outer wood should be considered. In addition, the selection of wood with higher strength properties can be achieved using the wood density and dynamic Young’s modulus as indicators.

Relationship between the xylem maturation process based on radial variations in wood properties and radial growth increments of stems in a fast-growing tree species, Liriodendron tulipifera

“…Thus, the rate of change in the aforementioned properties from the pith toward the cambium might differ among individual trees. On the other hand, the model with a y-value at the first annual ring from the pith of the individual tree was selected in vessel frequency, vessel diameter, wood Erdene-ochir et al [15] fiber diameter, wood fiber wall thickness, air-dry density, MOR, and compressive strength. This finding indicated that these wood properties depend on the values at the first annual ring, which differed among individual trees, and that the radial variation pattern itself is not affected by differences among individual trees.…”

“…The relationship between radial growth increments and the xylem maturation process based on radial variation patterns of single or several wood properties has been reported for several fast-growing tree species in dry [9], tropical [14], and subarctic climates [15] (Table 6). In these studies, wood properties became stable below the age of 10 years at the time of peak CAI and MAI values in L. tulipifera in Japan (Fig.…”

“…Numerous studies have investigated the relationship between the xylem maturation process and radial growth increments of stems expressed as CAI and MAI in many fast-growing tree species [3,5,7,9,12,13]. In previous research, we estimated this relationship in various fast-growing tree species in tropical and boreal zones [14,15]. In Eucalyptus camaldulensis in Thailand (tropical zone), after 5 years, the basic density and compressive strength values of the wood were stable, and the radial growth increments of stems reached maximum values [14].…”

“…In Eucalyptus camaldulensis in Thailand (tropical zone), after 5 years, the basic density and compressive strength values of the wood were stable, and the radial growth increments of stems reached maximum values [14]. However, based on an analysis of fiber increments in Betula platyphylla in Mongolia (boreal zone), xylem maturation began before the age of 10 years compared to the age showing maximum radial growth increments [15]. Thus, the relationship between the xylem maturation process and radial growth increments of stems might differ among properties, tree growth conditions, and others.…”

Influence of Silvicultural Operations on the Growth and Wood Density Properties of Mediterranean Pines

“…Besides the abovementioned wood properties that are desirable for high-quality uses, other characteristics such as wood density are a major physical criterion for wood quality [6] since they are related to many other aspects of quality such as wood strength and shrinkage, fiber properties, and flexibility or stiffness, among others [7,8]. Furthermore, it has been demonstrated that wood density affects carbon storage [9][10][11].…”