Growth, allometry and shade tolerance of understory saplings of four subalpine conifers in central Japan
Growth, allometry and shade tolerance of understory saplings of four subalpine conifers in central Japan
复制标题
日本中部四种亚高山针叶树林下幼树的生长、异速生长和耐荫性
DOI：
10.1007/s10265-013-0610-2
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发表时间：
2014
影响因子：
2.8
通讯作者：
Y.
中科院分区：
文献类型：
--
作者：
Takahashi;K. & Obata;Y.
日本中部亚高山森林中的针叶冷杉、马尾松、云杉、多叶铁杉。我们预计树种在耐荫性以及地上和地下结构上的差异对它们的共存是重要的。我们研究了林下树苗的净生产量和碳分配。虽然4种树种在树干高度上分配给根系的生物量相似，但其根区面积大于其他3种树种。异叶树种通常在山脊和岩坡等浅层土壤中占据优势地位，因此，广泛分布的侧根是对这种土壤条件的一种适应。不同树种的树冠宽度和枝叶质量最大，其次是黄杨和洪道沙打旺。虽然红松的叶质量在4个树种中最低，但由于每叶质量的净生产量最大，所以在每苗净生产量上没有物种差异。叶片寿命较长的顺序为：马尾松>杂叶杨>红毛委陵菜>威氏黄杨。维持当前幼叶质量所需的最小单位叶质量净生产量速率(MRNPLM)在海桑和杂叶杨中最低，并按ofA.veitchiiandP.jezoensisvar.hondoensis.A.mariesiiandT.diversifoliamay在遮荫条件下生存的顺序递增，其MRNPLM比其他两个物种低。因此，地上和地下结构和MRNPLM的物种差异反映了它们的耐荫和更新策略，这有助于它们的共存。
The conifersAbies veitchii,A.mariesii,Picea jezoensisvar.hondoensis,Tsuga diversifoliadominate in subalpine forests in central Japan. We expected that species differences in shade tolerance and in aboveground and belowground architecture are important for their coexistence. We examined net production and carbon allocation of understory saplings. Although the four species allocated similar amounts of biomass to roots at a given trunk height, the root-zone area ofT.diversifoliawas greater than that of the three other species.T.diversifoliaoften dominates shallow soil sites, such as ridge and rocky slopes, and, therefore, a wide spread of lateral roots would be an adaptation to such edaphic conditions. Crown width and leaf and branch mass were greatest forT.diversifoliaandA.mariesii, followed in order byA.veitchiiandP.jezoensisvar.hondoensis. Although leaf mass ofP.jezoensisvar.hondoensiswas lowest among the four species, species differences were not found in the net production per sapling because net production per leaf mass was greatest forP.jezoensisvar.hondoensis. The leaf lifespan was longer in the orderA.mariesii,T.diversifolia,P.jezoensisvar.hondoensisandA.veitchii. The minimum rate of net production per leaf mass required to maintain the current sapling leaf mass (MRNPLM) was lowest inA.mariesiiandT.diversifolia, and increased in the order ofA.veitchiiandP.jezoensisvar.hondoensis.A.mariesiiandT.diversifoliamay survive in shade conditions by a lower MRNPLMthan the two other species. Therefore, species differences in aboveground and belowground architecture and MRNPLMreflected their shade tolerance and regeneration strategies, which contribute to their coexistence.