摘要
[目的]了解几种丛生竹叶的平均叶面积(MLA)、比叶面积(SLA)和叶干物质含量(LDMC)沿冠层高度的垂直变化规律.[方法]对福建农林大学百竹园内12种丛生竹不同冠层高度叶片MLA、SLA和 LDMC 进行调查,分析丛生竹不同冠层MLA、SLA和LDMC的垂直空间结构与差异.[结果]不同丛生竹的上、中、下冠层MLA与LDMC变化较小,SLA变化较大,MLA与LDMC均以唐竹最高(上、中、下冠层MLA均值分别为26.0、33.7 、27.4 cm2;LDMC分别为766.0、814.8、792.4 m2/kg),LDMC以大黄苦竹最低(上、中、下冠层分别为528.4、548.5、479.0 mg/g);SLA均以高节竹最高(上、中、下冠层分别为629.0、284.9 、440.7 m2/kg);同竹种不同冠层间MLA差异不显著(P>0.05);除白哺鸡竹外,其他11种竹种3个冠层间的SLA差异不显著(P>0.05).[结论]光照、水分资源及养分在冠层不同高度的分配,共同导致MLA、SLA 和LDMC 沿冠层垂直方向发生变化.
Abstract
[Objective]To understand the vertical variations of MLA,SLA and LDMC along a canopy height of several sympodial bamboos.[Method]The MLA,SLA and LDMC of different height of canopy of 12 kinds of cluster bamboo in Fujian Agriculture and Forestry University were investigated.The vertical structure and difference of MLA,SLA and LDMC in different canopy of clustered bamboo were analyzed.[Result]The results showed that the changes of MLA and LDMC in the upper,middle and lower canopy of different clustered bamboos were smaller,and the change of SLA was greater,and MLA and LDMC of Sinobambusa tootsik were the highest (MLA in the upper,middle and lower canopy were 26.0,33.7 and 27.4 cm2,respectively,and LDMC was 766.0,814.8 and 792.4 m2/kg,respectively).The minimum LDMC was Pleioblastus amarus (LDMC in the upper,middle and lower canopy were 528.4,548.5,479.0 mg/g).The highest SLA was Phyllostachys prominens (the upper,middle and lower canopy were 629.0,284.9 and 440.7 m2/kg,respectively).There was no significant difference in MLA between the canopy of the same species (P>0.05).In addition to Phyllostachys dulcis,difference of SLA of other 11 kinds of bamboo species in 3 canopy was not significant (P>0.05).[Conclusion]The distribution of light,water resources and nutrients at different heights of canopy resulted in the change of MLA,SLA and LDMC along the vertical direction of canopy.