杨树农田防护林带单木叶面积的变化

杨树农田防护林带单木叶面积的变化

*

赵

东

1

杨喜田

1

樊巍

2

高喜荣

2

王齐瑞

2

（1.河南农业大学郑州450002；2.河南省林业科学研究院

郑州450008）

摘

要：

研究豫东平原5，7年生欧美杨107杨农田防护林带单木比叶面积、叶面积的变化，建立预测林带单木叶

面积的异速生长模型。结果表明：5，

7年生单木比叶面积平均分别为136.6，138.2cm 2·g －1，两者差异不显著；叶面积平均分别为45.4，

85.8m 2，两者差异显著。冠层位置对比叶面积、叶面积均有显著影响，从树冠的上层到下层，比叶面积显著增加；而叶面积在两林龄中垂直层次表现出差异性，在水平层次，由内层到外层，叶面积均显著增加。不同林龄林带具有不同级别的枝，各级别枝的叶面积间均有显著差异。异速生长关系表明：树高、胸径、冠长因子都能可靠地预测林带单木叶面积，相比而言，胸径和单木叶面积之间的异速生长模型在测算单木叶面积及其指数时较可靠、方便。关键词：

叶面积；异速生长关系；冠层位置；防护林带；欧美杨107杨

中图分类号：S758.1

文献标识码：A

文章编号：1001－7488（2011）04－0107－07

收稿日期：2010－03－31；修回日期：2010－11－03。

基金项目：国家“十一五”科技支撑项目“豫东平原农区农林复合系统可持续经营技术研究”（2006BAD03A0506）；林业公益性行业科研专项

“典型平原农区多目标农业防护林构建与可持续经营技术研究”（20070414）部分内容。*樊巍为通讯作者。

Variation of Leaf Area in Individual Tree for Poplar Shelterbelts

Zhao Dong

1

Yang Xitian

1

Fan Wei

2

Gao Xirong

2

Wang Qirui

2

（1.Henan Agricultural University Zhengzhou 450002；2.Henan Academy of Forestry Zhengzhou 450008）

Abstract ：Leaf area （LA ）as an essential part of crown structure affects both the growth of forests and protective effects

of shelterbelt.The variation in specific leaf area （SLA ）and leaf area with position in the crown was investigated for 5-year-old and 7-year-old Populus ˑeuramericana cv.“74/76”stand in Henan Eastern Plain.Allometric equations describing the leaf area of the entire crown were developed.The results showed that SLA on individual tree were 136.6，138.2cm 2

·g

－1

in 5-year-old and 7-year-old trees ，respectively.However ，leaf area on individual tree was significantly

influenced by tree age ，on average it were 45.4，85.8m 2

in 5-year-old and 7-year-old trees ，respectively.Specific leaf area and leaf area were significantly by the position in the crown.Specific leaf area increased significantly from the top to the bottom of the crown.Leaf area increased significantly from the top to the bottom of the crown for 5-year-old stand ，however ，it in the middle was significantly higher than that in the upper and the lower of the crown for 7-year-old stand ，and both increased significantly from the interior to the exterior of the crown.There were different classes of shoots in different stand age ，three classes of shoots in Populus ˑeuramericana cv.“74/76”aged 5years and four classes of shoots in it aged 7years.Leaf area among several orders of shoots had both significantly difference for 5-year-old and 7-year-old stand.Allometric relationships of leaf area with different tree characteristics indicated that stem diameter at breast height （DBH ），tree height （H ）and crown length （CL ）were reliable predictors of leaf area at the tree-level ，however ，the allometric relationships between DBH and leaf area at the tree-level were more reliable and convenient to predict the tree-level leaf area and to estimate leaf area index （LAI ）.Key words ：leaf area ；allometric relationship ；within-crown position ；shelterbelt ；Populus

ˑ

euramericana

cv.“74/76”

树冠是树木进行光合作用的场所，冠层内叶面积的分布与光能的截获紧密相关，影响树木生物量的积累和林分的生长（Bidlake et al.，1989；Kershaw et al.，1996；Massman ，1982）。树冠作为林分空间

分布状态的表现形式，对防护林的防护效能具有决定性作用（叶功富等，2000），而叶面积是树冠结构研究的重要内容。因此，研究农田防护林带单木的叶面积对研究其树冠发育规律及林带群落结构、防

活体叶面积测定仪/product/769.html