植物生态学报 ›› 2023, Vol. 47 ›› Issue (11): 1523-1539.DOI: 10.17521/cjpe.2022.0390

• 研究论文 • 上一篇    下一篇

辽东山区不同坡向长白落叶松人工林树冠特征与林木生长关系

和璐璐1, 张萱1, 章毓文1, 王晓霞1, 刘亚栋1, 刘岩1, 范子莹1, 何远洋2, 席本野1, 段劼1,**()   

  1. 1北京林业大学林学院, 北京 100083
    2重庆市林业局, 重庆 401147
  • 收稿日期:2022-10-07 接受日期:2023-02-24 出版日期:2023-11-20 发布日期:2023-12-22
  • 通讯作者: 段劼(duanjie@bjfu.edu.cn)
  • 作者简介:第一联系人:*同等贡献
  • 基金资助:
    中央高校基本科研业务费专项资金(2021ZY18);林业科学技术推广项目(2011-44)

Crown characteristics and its relationship with tree growth on different slope aspects for Larix olgensis var. changbaiensis plantation in eastern Liaoning mountainous area, China

HE Lu-Lu1, ZHANG Xuan1, ZHANG Yu-Wen1, WANG Xiao-Xia1, LIU Ya-Dong1, LIU Yan1, FAN Zi-Ying1, HE Yuan-Yang2, XI Ben-Ye1, DUAN Jie1,**()   

  1. 1College of Forestry, Beijing Forestry University, Beijing 100083, China
    2Chongqing Forestry Bureau, Chongqing 401147, China
  • Received:2022-10-07 Accepted:2023-02-24 Online:2023-11-20 Published:2023-12-22
  • Contact: DUAN Jie(duanjie@bjfu.edu.cn)
  • About author:First author contact:*Contributed equally to this work
  • Supported by:
    Fundamental Research Funds for the Central Universities(2021ZY18);Forestry Science and Technology Promotion Project(2011-44)

摘要:

树冠是林木形成碳水化合物和生产力的重要场所, 摸清林木与树冠生长的特征及其对环境的响应对理解植物环境适应性具有重要意义。该研究以辽东地区60块长白落叶松(Larix olgensis var. changbaiensis)人工林样地为研究对象, 对阴坡、阳坡两个坡向和3个林龄阶段(15-16 a、23-26 a、49-56 a)的林木和树冠生长进行了研究, 其中树冠生长指标包含了客观指标、主观指标和复合指标3种类型。研究结果表明: (1)各林龄阶段不同坡向林分平均胸径、平均树高、平均材积、平均相对优势木高无显著差异, 达成熟林时阳坡林分胸径分化程度显著高于阴坡。(2)综合分析3类树冠指标发现树冠受坡向影响, 表现出不同的生长适应策略。阳坡林木平均树冠长度、平均冠幅小, 林内冠层均一, 树冠体量小, 树冠生产效率较高; 阴坡林木平均树冠长度和平均冠幅较大, 林内超出主林层优势木多, 树冠体量大, 树冠生产效率较低。(3)除林分平均高径比外, 树冠客观指标均与生长指标呈正相关关系, 阳坡林木树冠随林龄增大对材积的贡献率减小, 体现在树冠长度、树冠率与生长指标呈极显著负相关关系, 阴坡林木树冠位置和圆满度是促进林木生长的主要因素。(4)树冠客观指标与各器官生物量均呈极显著正相关关系, 受光率、树冠表面积、树冠体积在各坡向均与林木生物量呈显著正相关关系, 顶梢枯死率均与各坡向林木生物量呈负相关关系, 阳坡林木树冠透光度、冠径比和树冠率增加, 则林木生物量下降, 阴坡林木树冠位置升高、圆满度增加会促进生物量积累。(5)相比所有生长指标和树冠指标, 树冠表面积对各器官生物量积累的解释效果最好。以上结果表明, 长白落叶松人工用材林树冠生长会显著促进林木生长, 但树冠生长与林木生长存在权衡关系, 并会随坡向发生改变。

关键词: 树冠, 坡向, 长白落叶松, 生物量, 权衡关系, 环境适应性

Abstract:

Aims Tree crown plays vital roles in carbohydrate accumulation and productivity formation, clarifying the variation pattern of tree growth and crown development, as well as their responses to the growing environment such as slope aspects, can help us to understand the adaption strategies of trees.

Methods In this study, Larix olgensis var. changbaiensis from 60 sites in east Liaoning were selected, and the responses of tree growth and crown development to different slope aspects (shady or sunny slope) and age classes (15-16 a, 23-26 a, 49-56 a) were analyzed. The three types of crown indicators, including objective indicators, subjective indicators, and composite indicators, were used to analyze the crown development in this study.

Important findings The results showed that: (1) No significant difference was found in diameter at breast height (DBH), tree height (H), wood volume, and relative dominant tree height among age classes. In comparison, the differentiation of DBH on the sunny slopes was significantly higher than that on the shady slopes in the mature age class. (2) By the comprehensive analysis of the three types of crown indicators, the crown exhibited distinct growth adaptation strategies but depending on slope aspects. Tree growing on the sunny slopes generally showed small crown length and width with uniform crown layer and high crown production efficiency. By contrast, tree growing on the shady slopes showed large crown length and width with large crown volume and low crown production efficiency. (3) Except for the ratio of H to DBH, all objective crown indicators were positively correlated to growth indicators. On the sunny slopes, the contribution of the crown to wood volume decreased with stand age, which could be proved by the significant negative correlation between crown length, crown ratio, and growth indicators. In addition, the crown position and crown fullness ratio were also the main factors that promoted stand growth at the shady slopes. (4) All the objective indicators were positively correlated to the biomass of each organ. On both slope aspects, whole tree biomass was positively correlated to crown light exposure, crown surface area, and crown volume, but negatively correlated to crown dieback. On the sunny slopes, whole tree biomass decreased with the increase of foliage transparency, ratio of crown density to DBH, and crown ratio, while on the shady slopes, biomass increased with higher crown position and crown fullness ratio. (5) Among all indicators, crown surface area showed the best indicator for explaining the biomass of each organ in this study. Overall, better crown development could significantly promote tree growth on Larix olgensis var. changbaiensis plantation, but the trade-off between crown development and tree growth that varies with slope aspects should be considered in such stand management.

Key words: tree crown, slope aspect, Larix olgensis var. changbaiensis, biomass, trade-off, environmental adaptation