Bond-Lamberty B, Wang C, Gower S T, Norman J
Department of Forest Ecology and Management, University of Wisconsin-Madison, 1630 Linden Drive, Madison, WI 53706, USA.
Tree Physiol. 2002 Oct;22(14):993-1001. doi: 10.1093/treephys/22.14.993.
Specific leaf area (SLA) and leaf area index (LAI) were estimated using site-specific allometric equations for a boreal black spruce (Picea mariana (Mill.) BSP) fire chronosequence in northern Manitoba, Canada. Stands ranged from 3 to 131 years in age and had soils that were categorized as well or poorly drained. The goals of the study were to: (i) measure SLA for the dominant tree and understory species of boreal black spruce-dominated stands, and examine the effect of various biophysical conditions on SLA; and (ii) examine leaf area dynamics of both understory and overstory for well- and poorly drained stands in the chronosequence. Overall, average SLA values for black spruce (n = 215), jack pine (Pinus banksiana Lamb., n = 72) and trembling aspen (Populus tremuloides Michx., n = 27) were 5.82 +/- 1.91, 5.76 +/- 1.91 and 17.42 +/- 2.21 m2 x kg-1, respectively. Foliage age, stand age, vertical position in the canopy and soil drainage had significant effects on SLA. Black spruce dominated overstory LAI in the older stands. Well-drained stands had significantly higher overstory LAI (P < 0.001), but lower understory LAI (P = 0.022), than poorly drained stands. Overstory LAI was negligible in the recent (3-12 years old) burn sites and highest in the 70-year-old burn site (6.8 and 3.0 in the well- and poorly drained stands, respectively), declining significantly (by 30-50%) from this peak in the oldest stands. Understory leaf area represented a significant portion (> 40%) of total leaf area in all stands except the oldest.
利用特定地点的异速生长方程，对加拿大曼尼托巴省北部北方黑云杉（Picea mariana (Mill.) BSP）火灾时间序列进行了特定叶面积（SLA）和叶面积指数（LAI）的估算。林分年龄从3年到131年不等，土壤分为排水良好或排水不良两类。该研究的目标是：（i）测量北方黑云杉为主的林分中优势树种和林下物种的SLA，并研究各种生物物理条件对SLA的影响；（ii）研究时间序列中排水良好和排水不良林分的林下和林上叶面积动态。总体而言，黑云杉（n = 215）、短叶松（Pinus banksiana Lamb.，n = 72）和颤杨（Populus tremuloides Michx.，n = 27）的平均SLA值分别为5.82±1.91、5.76±1.91和17.42±2.21 m2·kg-1。叶龄、林分年龄、树冠垂直位置和土壤排水对SLA有显著影响。在较老的林分中，黑云杉主导着林上LAI。排水良好的林分林上LAI显著更高（P < 0.001），但林下LAI更低（P = 0.022），比排水不良的林分。在最近（3 - 12年树龄）的火烧迹地，林上LAI可忽略不计，在70年树龄的火烧迹地最高（排水良好和排水不良的林分分别为6.8和3.0），在最老的林分中从这个峰值显著下降（下降30 - 50%）。除最老的林分之外，林下叶面积在所有林分中占总叶面积的很大一部分（> 40%）。
