Prediction of Static Bending Properties of Eucalyptus Clones Using Stress Wave Measurements on Standing Trees, Logs and Small Clear Specimens
Abstract
:1. Introduction
2. Materials and Methods
2.1. Sample Origin
2.2. Sampling and Measurements
2.3. Data Analysis
3. Results and Discussion
3.1. Stress Wave Measurements in Trees and Logs
3.2. Radial and Among-Clonal Variations of SWVS and Wood Properties
3.3. Prediction of Static Bending Properties Using Stress Wave Measurements on Standing Trees, Logs, and Small Specimens
4. Conclusions
- There was a significant difference in density and static properties in radial location and among Eucalyptus clones. Clones 3 and 5 had significantly higher AD, MOR, and MOE than other clones. Therefore, clones 3 and 5 might be appropriate for Eucalyptus tree breeding programs focused on improving wood quality, specifically for lumber production in the north central region or similar sites of Vietnam.
- SWVT and SWVL had positive correlations with both average MOE- and MOR-determined by static bending tests of small specimens. This implies that stress wave velocities measured using time of flight gives a good indication of static bending properties in Eucalyptus clones planted in Vietnam.
- At the specimen level, SWVS and AD were significantly correlated with static bending properties. Improved prediction of stiffness can be achieved when both SWVS and AD of specimens are used together to calculate dynamic modulus of elasticity (MOEd), while this combination does not improve predictions of bending strength, compared to using AD alone.
Author Contributions
Funding
Data Availability Statement
Acknowledgments
Conflicts of Interest
References
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Clone | Species | Code | n | DBH (cm) | Tree Height (m) |
---|---|---|---|---|---|
UP54 | E. urophylla × E. pellita | 1 | 5 | 14.24 ± 0.88 | 18.81 ± 0.54 |
UP95 | E. urophylla × E. pellita | 2 | 5 | 15.43 ± 0.58 | 20.01 ± 0.38 |
UP99 | E. urophylla × E. pellita | 3 | 5 | 13.17 ± 0.93 | 18.40 ± 0.60 |
U892 | E. urophylla | 4 | 5 | 14.18 ± 1.96 | 18.08 ± 0.63 |
U1427 | E. urophylla | 5 | 5 | 14.06 ± 1.09 | 16.48 ± 0.65 |
PN14 | E. urophylla | 6 | 5 | 13.83 ± 1.18 | 15.23 ± 0.30 |
Clone | n | SWVT (m/s) | SWVL (m/s) | ||||
---|---|---|---|---|---|---|---|
Mean | SD | Range | Mean | SD | Range | ||
1 | 5 | 3151 cd | 101 | 3047–3299 | 3229 c | 55 | 3166–3285 |
2 | 5 | 3559 ab | 129 | 3399–3704 | 3569 b | 85 | 3498–3714 |
3 | 5 | 3662 a | 86 | 3546–3759 | 3844 a | 91 | 3762–3989 |
4 | 5 | 3375 bc | 95 | 3279–3521 | 3588 b | 106 | 3449–3706 |
5 | 5 | 3288 c | 123 | 3160–3450 | 3553 b | 137 | 3354–3714 |
6 | 5 | 3013 d | 214 | 2686–3219 | 3231 c | 206 | 2989–3404 |
Mean | 30 | 3341 | 256 | 2686–3759 | 3503 | 246 | 2898–3989 |
Variable | Description | n | SWVS (m/s) | AD (g/cm3) | MOEd (GPa) | MOE (GPa) | MOR (MPa) | |
---|---|---|---|---|---|---|---|---|
Radial positions | 1 | Near pith | 40 | 4021 b ± 128 | 0.43 b ± 0.02 | 6.99 b ± 0.62 | 5.96 b ± 0.51 | 56.50 b ± 4.63 |
Near bark | 40 | 4244 a ± 168 | 0.48 a ± 0.02 | 8.71 a ± 0.84 | 7.38 a ± 0.69 | 69.59 a ± 4.69 | ||
2 | Near pith | 40 | 4229 b ± 131 | 0.46 b ± 0.02 | 8.27 b ± 0.70 | 6.57 b ± 0.57 | 62.37 b ± 7.01 | |
Near bark | 40 | 4353 a ± 57 | 0.51 a ± 0.01 | 9.69 a ± 0.39 | 7.92 a ± 0.60 | 76.22 a ± 4.88 | ||
3 | Near pith | 28 | 4226 b ± 122 | 0.53 b ± 0.07 | 9.52 b ± 1.86 | 8.24 b ± 1.71 | 77.45 b ± 14.60 | |
Near bark | 28 | 4421 a ± 122 | 0.58 a ± 0.05 | 11.42 a ± 1.28 | 9.73 a ± 1.23 | 92.50 a ± 11.71 | ||
4 | Near pith | 28 | 4234 b ± 153 | 0.47 b ± 0.03 | 8.39 b ± 1.08 | 7.30 b ± 0.92 | 65.09 b ± 6.36 | |
Near bark | 28 | 4360 a ± 125 | 0.52 a ± 0.03 | 9.84 a ± 0.89 | 8.63 a ± 1.02 | 76.36 a ± 4.90 | ||
5 | Near pith | 32 | 3744 b ± 149 | 0.59 a ± 0.02 | 8.32 b ± 0.74 | 7.02 b ± 0.77 | 80.42 b ± 6.16 | |
Near bark | 32 | 4016 a ± 83 | 0.60 a ± 0.03 | 9.61 a ± 0.67 | 8.39 a ± 0.66 | 87.47 a ± 4.63 | ||
6 | Near pith | 28 | 3772 b ± 144 | 0.50 b ± 0.03 | 7.07 b ± 0.77 | 5.97 b ± 0.78 | 57.01 b ± 11.10 | |
Near bark | 28 | 4034 a ± 186 | 0.57 a ± 0.02 | 9.25 a ± 0.72 | 7.50 a ± 0.83 | 76.13 a ± 6.10 | ||
Clones | 1 | 80 | 4133 b ± 186 | 0.46 e ± 0.03 | 7.85 c ± 1.14 | 6.67 d ± 0.94 | 63.05 c ± 8.05 | |
2 | 80 | 4291 a ± 118 | 0.49 d ± 0.03 | 8.98 b ± 0.91 | 7.24 bc ± 0.89 | 69.30 b ± 9.20 | ||
3 | 56 | 4323 a ± 194 | 0.56 b ± 0.06 | 10.47 a ± 1.85 | 8.98 a ± 1.65 | 84.98 a ± 15.15 | ||
4 | 56 | 4297 a ± 152 | 0.49 d ± 0.04 | 9.12 b ± 1.22 | 7.97 b ± 1.17 | 70.73 b ± 8.00 | ||
5 | 64 | 3880 c ± 182 | 0.60 a ± 0.03 | 8.97 b ± 0.96 | 7.70 b ± 0.99 | 83.94 a ± 6.47 | ||
6 | 56 | 3903 c ± 211 | 0.53 c ± 0.05 | 8.16 c ± 1.33 | 6.73 cd ± 1.11 | 66.57 bc ± 13.11 | ||
Mean | 392 | 4142 ± 249 | 0.52 ± 0.06 | 8.86 ± 1.48 | 7.48 ± 1.36 | 72.47 ± 13.11 |
Reference | Species | Country | Stand Age | AD (g/cm3) | MOEd (GPa) | MOE (GPa) | MOR (MPa) |
---|---|---|---|---|---|---|---|
This study | Eucalyptus | Vietnam | 6 | 0.46–0.60 | 7.85–10.47 | 6.67–8.98 | 63.05–84.98 |
De Melo et al. [26] | E. camaldulensis | Brazil | 5 | 0.56 | 7.01 | 77.95 | |
Kothiyal and Raturi [27] | E. tereticornis | India | 5 | 0.58 | 7.98 | 84.80 | |
Duong et al. [17] | A. auriculiformis | Vietnam | 5 | 0.50–0.59 | 8.70–10.95 | 7.37–9.14 | 83.81–101.43 |
Duong et al. [29] | A. mangium | Vietnam | 5 | 0.44–0.50 | 7.73–8.92 | 7.03–8.23 | 66.63–84.19 |
Source of Variation | df | SWVS | AD | MOEd | MOE | MOR | |||||
---|---|---|---|---|---|---|---|---|---|---|---|
p Value | Var (%) | p Value | Var (%) | p Value | Var (%) | p Value | Var (%) | p Value | Var (%) | ||
Clone (C) | 5 | 0.001 | 40.38 | 0.001 | 43.22 | 0.001 | 16.47 | 0.001 | 19.54 | 0.001 | 24.00 |
Ramet (T)/Clone | 24 | 0.001 | 2.18 | 0.001 | 2.23 | 0.001 | 2.33 | 0.001 | 2.90 | 0.001 | 2.00 |
Radial position (R) | 1 | 0.001 | 55.92 | 0.001 | 52.44 | 0.001 | 80.15 | 0.001 | 76.92 | 0.001 | 72.39 |
C × R | 5 | 0.001 | 0.86 | 0.001 | 1.72 | 0.001 | 0.63 | 0.677 | 0.10 | 0.001 | 1.17 |
T × R | 23 | 0.001 | 0.46 | 0.001 | 0.29 | 0.001 | 0.31 | 0.001 | 0.39 | 0.001 | 0.31 |
Residuals | 333 | 0.20 | 0.10 | 0.12 | 0.15 | 0.13 |
Level | Y | X | n | Equation | r | p-Value |
---|---|---|---|---|---|---|
Tree level | MOE | SWVT | 30 | Y = 0.003X − 1.27 | 0.61 | <0.001 |
MOR | 30 | Y = 0.021X + 2.50 | 0.53 | 0.003 | ||
Log level | MOE | SWVL | 30 | Y = 0.003X − 4.42 | 0.76 | <0.001 |
MOR | 30 | Y = 0.030X − 31.03 | 0.71 | <0.001 |
Clone | Variables | MOE | MOR | ||
---|---|---|---|---|---|
Equation | r | Equation | r | ||
1 | SWVS | MOE = 0.004SWVS − 10.51 | 0.83 *** | MOR = 0.03SWVS − 57.24 | 0.67 *** |
AD | MOE = 25.46AD − 4.96 | 0.85 *** | MOR = 229.26AD − 41.67 | 0.89 *** | |
MOEd | MOE = 0.76MOEd + 0.69 | 0.92 *** | MOR = 5.94MOEd + 16.43 | 0.84 *** | |
2 | SWVS | MOE = 0.005SWVS − 15.22 | 0.69 *** | MOR = 0.05SWVS − 131.10 | 0.60 *** |
AD | MOE = 22.42AD − 43.66 | 0.75 *** | MOR = 248.15AD − 51.40 | 0.81 *** | |
MOEd | MOE = 0.82MOEd − 0.11 | 0.83 *** | MOR = 8.29MOEd − 5.17 | 0.82 *** | |
3 | SWVS | MOE = 0.007SWVS − 20.79 | 0.81 *** | MOR = 0.06SWVS − 166.60 | 0.74 *** |
AD | MOE = 23.40AD − 4.03 | 0.92 *** | MOR = 217.08AD − 35.74 | 0.93 *** | |
MOEd | MOE = 0.85MOEd + 0.03 | 0.96 *** | MOR = 7.65MOEd + 4.87 | 0.93 *** | |
4 | SWVS | MOE = 0.006SWVS − 18.12 | 0.79 *** | MOR = 0.04SWVS − 79.81 | 0.67 *** |
AD | MOE = 26.76AD − 5.21 | 0.88 *** | MOR = 160.32AD − 8.17 | 0.78 *** | |
MOEd | MOE = 0.88MOEd − 0.06 | 0.92 *** | MOR = 5.16MOEd + 23.71 | 0.79 *** | |
5 | SWVS | MOE = 0.005SWVS − 10.18 | 0.84 *** | MOR = 0.02SWVS − 1.68 | 0.62 *** |
AD | MOE = 13.01AD − 0.04 | 0.36 ** | MOR = 74.11AD + 39.81 | 0.31 * | |
MOEd | MOE = 0.93MOEd − 0.60 | 0.89 *** | MOR = 4.61MOEd + 42.59 | 0.68 *** | |
6 | SWVS | MOE = 0.004SWVS − 10.17 | 0.82 *** | MOR = 0.04SWVS − 10.86 | 0.72 *** |
AD | MOE = 15.15AD − 1.32 | 0.63 *** | MOR = 215.42AD − 47.95 | 0.76 *** | |
MOEd | MOE = 0.74MOEd + 0.71 | 0.88 *** | MOR = 8.59MOEd − 3.55 | 0.87 *** | |
Combined | SWVS | MOE = 0.003SWVS − 6.66 | 0.63 *** | MOR = 0.02SWVS + 0.78 | 0.33 *** |
AD | MOE = 13.93AD + 0.29 | 0.64 *** | MOR = 173.61AD − 17.01 | 0.82 *** | |
MOEd | MOE = 0.85MOEd − 0.07 | 0.93 *** | MOR = 7.34MOEd + 7.41 | 0.83 *** |
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Van Duong, D.; Schimleck, L. Prediction of Static Bending Properties of Eucalyptus Clones Using Stress Wave Measurements on Standing Trees, Logs and Small Clear Specimens. Forests 2022, 13, 1728. https://doi.org/10.3390/f13101728
Van Duong D, Schimleck L. Prediction of Static Bending Properties of Eucalyptus Clones Using Stress Wave Measurements on Standing Trees, Logs and Small Clear Specimens. Forests. 2022; 13(10):1728. https://doi.org/10.3390/f13101728
Chicago/Turabian StyleVan Duong, Doan, and Laurence Schimleck. 2022. "Prediction of Static Bending Properties of Eucalyptus Clones Using Stress Wave Measurements on Standing Trees, Logs and Small Clear Specimens" Forests 13, no. 10: 1728. https://doi.org/10.3390/f13101728
APA StyleVan Duong, D., & Schimleck, L. (2022). Prediction of Static Bending Properties of Eucalyptus Clones Using Stress Wave Measurements on Standing Trees, Logs and Small Clear Specimens. Forests, 13(10), 1728. https://doi.org/10.3390/f13101728