光皮桦人工林生长规律与种质评价年龄的研究

摘要

The standard trees of different diameter classes of 14-year-oldBetula luminiferaplantation in the northwest of Guangxi were selected to stimulate the growth dynamics of DBH, tree height and individual volume by stem analysis and Richard’s regression analysis. The results showed that there were significant differences in the relationships between DBH, tree height, individual volume and tree age (P<0.001) and the regression coefficients were 0.86, 0.95 and 0.84 respectively, indicating that these regression models could be used to predict the growth of Betula luminifera plantation. The fast-growing periods of DBH, tree height and individual volume were from first to sixth, first to seventh and sixth to twelfth year, respectively. However, the preliminary and final age of evaluating the growth of this species were from seventh to eighth year, and twelfth year according to the characteristics of individual differentiation.%以桂西北地区光皮桦人工林为研究对象，以更全面反映林分整体生长规律的径阶标准木为材料，通过树干解析及采用Richards曲线方程进行建模，对14年生光皮桦人工林的胸径、树高和单株材积的生长过程进行了精度较高的拟合，并据此分析了光皮桦人工林胸径、树高及单株材积的生长节律。结果表明：光皮桦胸径、树高及材积与生长年龄的回归关系均达到极显著水平（p＜0.001），拟合度分别为86.1%、95.1%、84.1%，模拟方程可用于光皮桦人工林的生长分析和预测。光皮桦人工林的胸径、树高与材积的速生期分别出现在1～6、1～7和6～12 a，根据林分个体分化的初显与稳定两个特征，确定7～8年生、12年生可分别作为光皮桦种质评价的初选年龄与决选年龄。