撑麻8号立竹构件性状及其生物量积累分配特征

Modular Characteristics and Biomass Accumulation and Allocation of Bambusa Pervariabilis Mc-Clure×Dendrocalamus latiflorus Munro No 8

为揭示不同年龄撑麻8号立竹构件特征及生物量积累分配规律,测定了1~5年生撑麻8号立竹构件性状及秆、枝、叶生物量,分析了秆、枝、叶生物量积累与分配特征。结果表明,随立竹年龄增加,立竹胸径、全高、枝下高、节数、出叶强度均总体呈下降变化趋势,而冠幅、出枝强度则总体升高;2 a、3 a立竹具有较大胸径、出枝强度和出叶强度,且3 a及以上立竹秆含水率最低,材性最佳。随立竹年龄增加,立竹秆、叶及总生物量均呈先升高而后下降趋势,而枝生物量则总体升高。秆生物量分配比例呈先下降而后升高变化趋势,而枝、叶生物量比例均总体上先升高而后下降。综合分析表明,2 a、3 a立竹具有较大的胸径、出枝强度与出叶强度及构件生物量,呈现较高的生产潜力。因此,丰产林培育过程中,宜多留养1 a、2 a立竹,伐除部分3 a及以上立竹。

In order to reveal the modular characteristics and biomass accumulation and allocation of Bambusa Pervariabilis Mc-Clure×Dendrocalamus latiflorus Munro No 8,and provide a guidance for the management of high-yield bamboo forest,the modular properties and stem,branch,leaf biomass of 1-5 a bamboos were determined,and biomass allocation were analyzed.With the increase of bamboo age,diameter at breast height(DBH),total height,height under the first branch,node number and leafing intensity decreased,while crown width,branching strength increased.The 2 a and 3 a bamboos had bigger DBH,leafing,branching intensity,and 3 a bamboos had the lowest water content and excellent wood properties.With the bamboo age increasing,the stem,leaf and total biomass first increased and then decreased,while the branch biomass increased.The biomass proportion of stems first decreased and then increased,while that of leaves and branches first increased and then decreased.On the whole,it was indicated that the 2 a and 3 a bamboos had bigger DBH,higher leafing,and branching intensities,and higher modular biomass,showing high productive potential.Thus,in the cultivation practice of high-yield bamboo forests,it is advisable to keep the 1 a and 2 a bamboos,and to partially remove the≥3 a bamboos.