植物生态学报 ›› 2017, Vol. 41 ›› Issue (6): 661-669.DOI: 10.17521/cjpe.2016.0257

• 研究论文 • 上一篇    下一篇

不同密度旱柳的树冠构型与光截获

陈静, 赵成章*(), 王继伟, 赵连春   

  1. 西北师范大学地理与环境科学学院, 甘肃省湿地资源保护与产业发展工程研究中心, 兰州 730070
  • 收稿日期:2017-05-03 接受日期:2016-08-04 出版日期:2017-06-10 发布日期:2017-07-19
  • 通讯作者: 赵成章
  • 作者简介:

    * 通信作者Author for correspondence (E-mail:sunzhiqiang1956@sina.com)

  • 基金资助:
    基金项目 国家自然科学基金(41461013和91125014)

Canopy structure and radiation interception of Salix matsudana: Stand density dependent relationships

Jing CHEN, Cheng-Zhang ZHAO*(), Ji-Wei WANG, Lian-Chun ZHAO   

  1. College of Geography and Environmental Science, Northwest Normal University, Research Center of Wetland Resources Protection and Industrial Development Engineering of Gansu Province, Lanzhou 730070, China
  • Received:2017-05-03 Accepted:2016-08-04 Online:2017-06-10 Published:2017-07-19
  • Contact: Cheng-Zhang ZHAO
  • About author:

    KANG Jing-yao(1991-), E-mail: kangjingyao_nj@163.com

摘要:

植物可以通过调整树冠构型和光截获来增强自身的光合效率和竞争力。在甘肃省张掖市黑河干流边缘的洪泛平原湿地选取I (25-36 Ind.·plot-1)、II (37-48 Ind.·plot-1)和III (49-60 Ind.·plot-1) 3个密度梯度, 研究了不同密度旱柳(Salix matsudana)的冠层厚度、冠层面积和冠层光截获, 以及它们的相互关系。结果表明: 随旱柳种群密度增加, 土壤水分逐渐增加、土壤电导率和水分利用率逐渐减小, 旱柳枝长度与冠层厚度呈逐渐增大的趋势, 光合有效辐射、分枝数、分枝角度与冠层面积呈逐渐减小的趋势, 叶面积指数和光截获、净光合速率和蒸腾速率在中密度样地最大; 旱柳的光截获与冠层厚度和冠层面积在低密度样地分别呈极显著正相关和负相关关系, 在高密度样地呈显著正相关和负相关关系(p < 0.05), 在中密度样地均呈极显著正相关关系(p < 0.01)。旱柳在低密度选择减小光截获与冠层厚度而增大冠层面积的水平空间拓展模式, 在高密度倾向于垂直空间拓展模式, 反映了植物树冠构型在不同生境中的表型可塑性变化。

关键词: 光截获, 冠层厚度, 冠层面积, 密度, 旱柳

Abstract:

Aims Plants can enhance their photosynthetic efficiency and competitiveness by adjusting canopy structure and radiation interception. The objective of this paper was to quantify the relationship between canopy structure (crown depth and crown area) and light interception (LI) in a Salix matsudana stand under three different stand densities in a flood plain of Zhangye.Methods Our study site is located at the Heihe flood plain of Xichengyi in Ganzhou district, Zhangye City, Gansu Province in the middle Heihe River, where S. matsudana is the dominant species. Based on stand density (10 m × 10 m), the S. matsudana community is divided into three types: low density (I, 25-36 Ind.·plot-1), medium density (II, 37-48 Ind.·plot-1), and high density (III, 49-60 Ind.·plot-1). Community characteristics, soil physical and chemical properties of each type were measured. At each plot, we measured photosynthetically active radiation (PAR), LI, net photosynthetic rate (Pn), transpiration rate (Tr), crown depth, crown area, leaf area index (LAI), twig numbers, twig length, and bifurcation angle. The standardized major axis (SMA) estimation method was used to determine the relationships between LI and canopy structure.Important findings With increasing in stand density, we found that soil moisture increased, and soil electric conductivity decreased, while twig length and crown depth increased, and PAR, twig numbers, bifurcation angle and crown area decreased. LAI and LI, Pn and Tr reached their maximum at the stand of medium density. There was a significant, positive correlation and negative correlation (p < 0.01), respectively, between the LI, crown depth and crown area at low density (I), whereas low significant (p < 0.05) at high density (III), and high significantly positive correlation (p < 0.01) at the medium density (II). S. matsudana has more horizontal branches that reduce LI. Canopy thickness and increased crown area at low density. More vertical distribution of branches at high density, and a more balanced spacial distribution were found at medium density.

Key words: light interception, crown depth, crown area, density, Salix matsudana