从异龄叶性状分析几种常绿阔叶植物变异与关联

该研究从个体与物种两个水平分析福建省鬼洞山中亚热带常绿阔叶次生林中七种阔叶树种异龄叶的平均叶面积(MLA)、比叶面积(SLA)和叶干物质含量(LDMC)三个性状的变异及关联,探讨叶性状物质分配策略对植物生活策略优化的限制性影响。结果表明:(1)对七种阔叶树种的个体和物种水平变异系数而言,均为MLA(82.9%;76.9%)SLA(38.9%;35.5%)LDMC(25.4%;23.8%);在个体和物种水平上当年生叶片MLA变异系数(71.5%;64.0%)小于往年生叶片(72.2%;65.8%),SLA、LDMC值则相反。(2)在个体和物种水平,当年生叶MLA对往年生叶MLA变异的解释率分别为50.1%和61.5%,当年生叶SLA对往年生叶SLA变异的解释率分别为56.6%和77.0%,当年生叶LDMC对往年生叶LDMC变异的解释率分别为51.7%和68.3%。(3)7种亚热带常绿阔叶植物异龄叶MLA、SLA与LDMC变化规律说明,当年生叶与往年生叶投资相同干物质,当年叶可形成更大的叶面积,且叶面积建成的消耗较往年叶小。研究认为,异龄叶性状在异龄叶间存在变异与关联,叶面积形成过程中生物量建成与消耗的协调可能影响植物叶片的发育。

Variation and correlation of several evergreen broad- leaved trees on uneven-aged foliar traits

The changes of foliar traits within uneven-aged leaves reflect life strategy optimization under the complex environment of plants. Analysis on life strategy optimization of evergreen board-leaved plants from foliar traits of uneven-aged leaves could help us better understand plant adaption and evolution and material allocation strategy. In the paper, seven common broad-leaved tree species were studied in subtropical evergreen secondary forests of Guidong Hill of Fuzhou, Fujian Province. The variability and correlation of MLA(mean leaf area), SLA(specific leaf area)and LDMC (leaf dry matter content)in current-year and former-year leaves were compared at both individual and species levels. The results were as follows:(1)At both individual and species levels, variance coefficients were the highest in MLA(82.9% and 76.9%), followed by SLA(38.9% and 35.5%)and LDMC(25.4% and 23.8%). The variability coefficients of MLA were lower in current-year leaves(71.5% and 64%)than that of previous-year leaves(72.2% and 65.8%), while SLA and LDMC showed the reverse trend.(2)At individual level, the values of MLA, SLA and LDMC in current-year leaves explained 50.1%, 56.5% and 51.7% of the former-year leaves, while at the species level, they were 61.5%, 77.0% and 68.3% respectively.(3)The change of MLA, SLA and LDMC in uneven-aged foliar traits in seven broad-leaved trees showed that as to the same dry matter invested, larger leaf area and lower leaf construction cost could be found in current-year leaves. In conclusion, uneven-aged foliar traits vary and connect significantly with change of leaf age. Trade-offs between biomass construction and cost in leaf area production might affect plant leaf development.