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

Journal of Wood Science

Official Journal of the Japan Wood Research Society

Table 3 Comparison of AIC values in the linear and nonlinear mixed-effects models for radial variations in the wood properties in relation to cambial age

Property	Model I	Model II	Model III
WFL	− 138.98	− 224.91	− 192.38
VEL	− 315.07	− 325.41	− 320.24
BD	− 209.97	− 239.75	− 209.04
AD	− 62.67	− 71.25	− 45.98
DMOE	123.38	110.54	128.95
MOE	113.46	103.43	123.21
MOR	258.10	252.49	266.34
U	248.73	242.57	253.86
CS	184.71	175.35	193.46
SS	112.06	98.46	123.28

Number of trees = 10. AIC, Akaike Information Criterion; WFL, wood fiber length; VEL, vessel element length; BD, basic density; AD, air-dry density after drying at around 22 °C and 65% relative humidity for 2 weeks (11.3 ± 0.5% of moisture content); DMOE, dynamic Young’s modulus; MOE, modulus of elasticity; MOR, modulus of rupture; U, absorbed energy in impact bending; CS, compressive strength parallel to grain; SS, shearing strength of small clear specimens. Formulae for the models are listed in Table 2. Bold indicates the smallest AIC among the developed models for each of the examined wood properties