长叶苦竹新造林的生长发育规律研究

【目的】为揭示长叶苦竹(Pleioblastus chino var.hisauchii)新造林的生长发育规律，探究不同年龄竹株的秆形特征及不同龄级竹地下茎的鞭根生长情况，为长叶苦竹及其他混生型竹的栽培养护和经营管理提供参考。【方法】调查了南京林业大学溧水白马实验基地长叶苦竹新造林5年时的年龄结构和空间分布，标记整片竹林每株竹子的位置和年龄信息，随机选取3株1～5年生健康无病虫害竹株，测定其地径、株高、枝下高、每节节长和对应的节径等指标。追踪1～5年生竹鞭系，统计鞭段数、鞭节数、岔鞭数、芽数，测量鞭长、鞭径、鞭节长等指标。【结果】随着长叶苦竹新造林的更新，前4年新龄竹株数呈递增趋势。地径、株高和枝下高随竹龄的增长均呈递减趋势，且不同年龄竹株的地径和株高、枝下高和株高均存在线性正相关关系。竹秆每节节径由基部到梢部呈递减趋势，且每节节长和对应的节径存在线性正相关关系。新龄竹每节节径、每节节长、平均节径和平均节长均大于老龄竹。鞭径、总鞭长、鞭段数和芽数随竹龄的增长呈递减趋势。鞭长、鞭节长、岔鞭数和笋芽数随竹龄的增长呈先增后减的趋势，在造林第4年时达到最高。【结论】长叶苦竹新造林的年龄结构呈上...

Growth rules for a new stand of Pleioblastus chino var. hisauchii

【Objective】 This study revealed the growth rule of a new stand of Pleioblastus chino var. hisauchii, and explored the culm characteristics and rhizome growth of bamboo plants at different ages, providing a theoretical basis for cultivation and management of P. chino var. hisauchii and other bamboo species with mixed rhizome. 【Method】 We investigated the age structure and spatial distribution of 5-year-old P. chino var. hisauchii forest in the Baima experimental base of Nanjing Forestry University in Lishui District, Nanjing City. We first marked the location and age information of each bamboo plant in the forest, and randomly selected three healthy and disease-free bamboo plants at 1, 2, 3, 4 and 5 year-old. Then we measured their ground diameter, plant height, under-branch height, node length and corresponding node diameter. In addition, we traced the rhizome systems at 1, 2, 3, 4 and 5 year-old. Next, we counted the number of rhizome segments, rhizome nodes, rhizome branches buds, determined the rhizome length, rhizome diameter, rhizome node length and other indicators.【Result】 With the regeneration of new plantation forest, the number of young plants increased gradually during the previous 4 years. The ground diameter, plant height and under-branch height decreased with age. There was a linear positive correlation between ground diameter and plant height and between the under-branch height and plant height. The node diameter showed a decreased trend from base to top. There was also a linear positive correlation between the node length and node diameter. The node diameter, node length, average node diameter, and average node length of young bamboo plants were larger than those of old plants. The rhizome diameter, total rhizome length, number of rhizome segments and buds decreased with age. However, the rhizome length, rhizome node length, number of rhizome branches and shoot buds increased at first and then decreased with age, peaking in the fourth year.【Conclusion】 The new plantation forest showed an upward trend in an age structure, which was stable in the fourth year. The number of young bamboo plants was larger than that of the old plants in the previous 4 years. The young bamboo plants spread around with mother bamboo at the center. In general, the growth vigor of the aboveground and underground parts of bamboo plants decreased with age, which was strongest at two years of age.