Relating Breast-Height Wood Properties to Whole-Stem Wood Properties in Loblolly Pine

prediction models;wood density;lignin;alpha-cellulose;tree improvement

Aspinwall, Michael Joseph ; Dr. Fikret Isik, Committee Member,Dr. Marcia L. Gumpertz, Committee Member,Dr. Bailian Li, Committee Chair,Dr. Steven E. McKeand, Committee Co-Chair,Aspinwall, Michael Joseph ; Dr. Fikret Isik ; Committee Member ; Dr. Marcia L. Gumpertz ; Committee Member ; Dr. Bailian Li ; Committee Chair ; Dr. Steven E. McKeand ; Committee Co-Chair

University:North Carolina State University

关键词: prediction models;    wood density;    lignin;    alpha-cellulose;    tree improvement;   

Others  :  https://repository.lib.ncsu.edu/bitstream/handle/1840.16/1727/etd.pdf?sequence=1&isAllowed=y

美国|英语

来源: null

【 摘 要 】

Prediction models describing the relationship between breast-height wood properties (wood density, α-cellulose content, and lignin content) and whole-stem wood properties were developed for juvenile and mature loblolly pine.Both genetic and environmental effects were examined when predicting whole-stem wood properties in juvenile loblolly pine.Also, the relationship between juvenile, transition, and mature wood properties and whole-stem wood properties were analyzed in both juvenile and mature loblolly pine.The juvenile trees used in this study were made up of 24 trees; 4 clones, 3 ramets per clone, replicated over two sites.The mature trees sampled in this study were 20 unrelated 20-year-old trees.For juvenile loblolly pine, significant differences in all growth and wood property traits, excluding breast-height transition wood lignin content, breast-height juvenile α-cellulose content, and breast-height transition wood α-cellulose content were found between sites.At the Florida and Alabama sites, mean breast-height wood density values were 479.75 ± 8.27 and 424.37 ± 7.23 kg⁄m3, respectively.Across both sites, mean breast-height wood density values were 450.86 ± 7.96 kg&⁄m3.Mean whole-stem values were 383.66 ± 4.29 and 429.27 ± 7.74 kg⁄m3 at the Alabama and Florida sites respectively.At the Alabama site, mean breast-height α-cellulose content was 42.12 ± .23%, while mean breast-height α-cellulose content at the Florida site was 42.94 ± .21%.Mean whole-stem α-cellulose content at the Florida site was 41.89 ± .18% and mean whole-stem α-cellulose content at the Alabama site was 41.25 ± .22%.Also, at the Florida and Alabama sites mean breast-height lignin content values were 27.10 ± .17% and 28.22 ± .22%, respectively.Calculated mean whole-stem lignin content was 27.21 ± .15% at the Florida site and 28.59 ± .13% at the Alabama site.No significant clonal differences were found for any trait except breast-height juvenile wood α-cellulose content and height.Both linear and polynomial models were developed for describing the relationship between breast-height wood properties and whole-stem wood properties.Coefficients of determination for wood density ranged from 0.72 to 0.92 when data from both sites were combined.Across sites, coefficients of determination ranged from 0.43 to 0.73 for α-cellulose and 0.58 to 0.82 for lignin content.Correlations between breast-height wood properties and whole-stem wood properties were high and ranged from 0.84 to 0.92.Significant correlations were also found between breast-height juvenile and transition wood properties and whole-stem wood properties.However, the best predictor of whole-stem wood properties proved to be the entire breast-height pith to bark sample.For mature loblolly pine, both linear models were developed that described the relationship between breast-height wood properties and whole-stem wood properties.In mature loblolly pine, mean breast-height wood density was 455.25 ± 4.15 kg⁄m3 and mean whole-stem wood density values was 414.52 ± 4.18 kg⁄m3.Mean breast-height α-cellulose yield was 41.1 ± .22 % and mean whole-stem α-cellulose yield was 40.77 ± .20 %.Mean breast-height lignin content was 27.94 ± .14 % while mean whole-stem lignin content was 28.41 ± .12 %.On average, breast-height lignin content was about 0.47 % lower than whole-stem lignin content.Coefficients of determination for wood density ranged from 0.27 to 0.85.Coefficients of determination ranged from 0.42 to 0.95 and 0.59 to 0.85 for α-cellulose and lignin content respectively.For juvenile wood, correlations between breast-height wood properties and whole-stem wood properties ranged from 0.62 to 0.92 and correlations with whole-stem wood properties ranged from 0.77 to 0.90 for breast-height transition wood and from 0.44 to 0.84 for mature wood.Positive correlations were found between lignin measurements and growth measurements (0.12 to 0.24).For mature loblolly pine, the entire breast-height sample was the best predictor of whole-stem wood properties.Depending upon the trait of interest, breast-height transition wood also was an adequate predictor when compared to juvenile and mature wood.