植物生态学报 ›› 2018, Vol. 42 ›› Issue (9): 917-925.doi: 10.17521/cjpe.2018.0087

• 研究论文 • 上一篇    下一篇

测定森林树木叶面积的最适叶片数是多少?

高思涵,葛珏希,周李奕,朱宝琳,葛星宇,李凯(),倪健()   

  1. 浙江师范大学化学与生命科学学院, 浙江金华 321004
  • 收稿日期:2018-04-16 修回日期:2018-06-09 出版日期:2018-09-20 发布日期:2018-06-11
  • 通讯作者: 李凯,倪健 E-mail:likai@zjnu.edu.cn;nijian@zjnu.edu.cn
  • 基金资助:
    国家自然科学基金(41471049)

What is the optimal number of leaves when measuring leaf area of tree species in a forest community?

GAO Si-Han,GE Yu-Xi,ZHOU Li-Yi,ZHU Bao-Lin,GE Xing-Yu,LI Kai(),NI Jian()   

  1. College of Chemistry and Life Sciences, Zhejiang Normal University, Jinhua, Zhejiang 321004, China
  • Received:2018-04-16 Revised:2018-06-09 Online:2018-09-20 Published:2018-06-11
  • Contact: Kai LI,Jian NI E-mail:likai@zjnu.edu.cn;nijian@zjnu.edu.cn
  • Supported by:
    Supported by the National Natural Science Foundation of China(41471049)

摘要:

植物形态性状叶面积简单易测, 能够反映植物对环境的适应与响应, 指示生态系统的功能与过程。在野外测定叶面积时, 叶片取样数量往往采用约定俗成的10-20片, 但到底采集多少叶片才是最优和最具代表性, 却少有探究。该研究以浙江金华山常绿落叶阔叶混交林的优势树种木荷(Schima superba)与枫香树(Liquidambar formosana)为研究对象, 通过对5个胸径等级植株和每个植株6个方位开展大批量叶片取样(>2 500个), 分析两个树种的叶面积变异特征, 探讨叶片取样数量为多少才能最代表该森林类型的叶片大小性状规律。结果表明, 常绿乔木木荷平均叶面积与变幅均小于落叶乔木枫香树。木荷叶面积与胸径无显著相关性, 而枫香树叶面积与胸径有较显著相关性, 但两个树种均在中胸径等级(15-20 cm)差异不显著; 两个树种的叶面积与采样方位无显著相关性, 但在东、西和底部的差异不显著。因此, 综合考虑代表性与野外可操作性, 叶片采集首选中胸径成树的底部叶片。随机抽样统计可知, 树木叶面积测定的最适叶片采集数量因物种而异, 木荷的最适叶片采集数量为40, 而枫香树最少为170片。因此, 在叶面积测定时, 叶片采集的数量应该不能只局限在10-20片, 在人力、物力和时间等条件允许的情况下, 应该尽可能多地测定较多叶片的叶面积。

关键词: 植物功能性状, 叶面积, 取样数量, 取样方位, 树龄, 常绿落叶阔叶混交林

Abstract:
Aims Leaf size, as one of the easier measured plant morphological traits, reflects response and adaptation of plants to environment and indicates functions and processes of ecosystem. When measuring leaf size (the leaf area, LA) on the field, the common accepted practice considers that the number of leaves picked off is often 10-20. However, what is the optimal number of leaves remains unknown. In this study, we attempt to determine how many leaves should be investigated when the leaf size of a tree is measured.
Methods This study selected two dominant tree species (Schima superba, Ss and Liquidambar formosana, Lf) from a broadleaved evergreen and deciduous mixed forest in Jinhua Mountain of Zhejiang Province, eastern China. On the basis of sampling (>2 500 leaves for each tree) in five classes of the diameter of breast height (DBH) of tree species and at six directions for each individual, variations of LA in the two tree species are statistically analyzed. The optimal number of leaves, which can mostly represent the common leaf size feature, is further investigated.
Important findings Mean LAof the evergreen tree Ss was smaller than that of the deciduous tree Lf. The former was (41.60 ± 10.88) cm 2 (16.74-100.80 cm 2) and the latter was (57.65 ± 19.35) cm 2 (11.31-129.51 cm 2). LA of Lf was significantly related to the DBH, but LAof Ss was not. LA of both trees in the middle DBH class (15-20 cm) was not significantly different from their means. LA of two trees have no significant correlations with the sampling directions, but LA at the east, west and bottom had no significant relationships with their means. Considering the representativeness and practicality in the field sampling, the priority of selecting leaves can target the bottom direction of middle diameter mature trees. Random sampling analysis indicated that, the optimal number of leaves for tree LA measurement is species specific. The optimal number of leaves for Ss is 40 and for Lf is at least 170, respectively. Therefore, when measuring leaf area in a forest community, the optimal sampling number of leaves should not be limited to 10-20 leaves. Under sufficient labor, material and time, more leaves should be measured.

Key words: plant functional traits, leaf area, sampling number, sampling direction, tree age, evergreen and deciduous broadleaved mixed forest