浙江省毛竹秆形结构特征

  目的  解析秆形结构因子之间的关系及其主导因子，并以竹节所处高度与竹高的比值(即相对高，取值为0~1)代替实际高，分析秆形结构因子及其依赖于相对高的分布规律，可以辅助判断毛竹Phyllostachys edulis生长发育状况。  方法  在浙江省不同区域共选择10个县市(区)设置毛竹林调查样地，测量样竹的竹节数、竹节长和中央直径等秆形结构因子，用抛物线和直线拟合秆形结构因子依赖于相对高在竹秆上的分布规律，通过相关性分析解析秆形结构因子之间的关系，应用因子分析解析秆形结构因子中的主要因子。  结果  毛竹竹节数集中在53~67节，符合正态分布，95%置信水平下毛竹竹节数平均数的置信区间为(58.1, 60.4)；竹节长和竹节中央直径依赖于相对高分布分别具有抛物线和直线分布特征。竹秆高度每增加10%，竹节中央直径约下降10%。随着径阶的增大，最长竹节长有逐渐增大的趋势，但最长竹节的相对高没有明显差异，均为0.47~0.52；胸径与竹节数、1/2高节长、最长竹节长和胸高竹节长呈极显著正相关(P＜0.01)，与胸高节号呈极显著负相关(P＜0.01)。  结论  稳定性和差异性并存是毛竹秆形结构因子的主要特点。不同径阶毛竹最长竹节的相对高没有明显差异，均约在1/2竹高处；竹子越粗壮，节数越多，1/2高节长越长，胸高以下平均竹节长越长；壁厚因子、1/2高节长、竹节数和胸高处秆形因子是反映毛竹秆形结构的主要因子。图6表6参28

On the structure characteristics of culm form of Phyllostachys edulis in Zhejiang Province

  Objective  With an analysis of the relationship between stalk structure factors and the dominant factors in stalk structure factors as well as an investigation into the stalk structure factors of culm and their distribution rules dependent on relatively high with the actual high replaced by the ratio of bamboo joint height and bamboo high (i. e. relative high, value range 0?1), this study is aimed to reveal the structure characteristics of culm form so as to better evaluate the growth and development of bamboo (Phyllostachys edulis).  Method  With 10 counties and cities (districts) of Zhejiang Province selected to set up sample plots of moso bamboo forest, the sample bamboo trees were cut down to measure the number of bamboo nodes, the length of bamboo nodes and the central diameter of bamboo nodes. Then the distribution patterns of culm form factors depending on relative height were fitted by parabola and line before the relationship between culm form factors was investigated with the correlation analysis whereas the main culm structure factors were studied with the factor analysis.  Result  The number of bamboo bamboo knots was concentrated in 53?67 sections, consistent with the normal distribution, and the confidence interval of the average bamboo knots at the 95% confidence level is (58.1, 60.4). The length of nodes and the central diameter of nodes depended on the relative height distribution with parabola and straight line distribution respectively while the central diameter of bamboo nodes decreased by 10% with a 10% increase of culm height. With the increase of diameter grades, the length of longest bamboo node tended to increase gradually, but there is no significant variation in the relative height of the longest bamboo node ranging between 0.47 and 0.52, and DBH was positively correlated with the number of bamboo nodes, length of node in half height, the length of longest node and the length of node in chest height (P＜ 0.01), while negatively correlated with the number of nodes in chest height (P＜0.01).  Conclusion  The culm form of bamboo was featured with both stability and variation but there was no significant variation in the relative height of the longest bamboo nodes with different diameter class, generally at half height. Also, the bigger the bamboo was, the larger the number of nodes was, the longer the bamboo nodes were, and the longer the average length below the chest height was. The wall thickness factor, the length of nodes at half height, the number of bamboo nodes and the culm factor in the height of the chest are the main structural factors reflecting the culm structure. Ch, 6 fig. 6 tab. 28 ref.]