Körner Ch, Renhardt U
Institut für Botanik, Universität Innsbruck, Sternwartestrasse 15, A-6020, Innsbruck, Austria.
Oecologia. 1987 Dec;74(3):411-418. doi: 10.1007/BF00378938.
Partitioning patterns in 22 exclusively low and 27 exclusively high altitude perennial herbaceous species were examined in order to test the hypothesis that plants of high altitudes allocate more dry matter to below-ground parts and in particular to storage organs, than typical low altitude plants. Our results raise some doubts about the general validity of this hypothesis. The mean fractions of total dry matter allocated to green leaves (22±2% s.e. at low and 24±2% at high altitude) and special storage organs (28±4% at both altitudes) do not differ significantly among sites. The mean relative portions of total dry matter allocated to above-ground plant parts amount to 57±3% at low and 42±3% at high elevation (P=0.002) and differ less than often assumed. The greater below-ground fraction at high altitude results from reduced stem and proportionally increased fine root compartments. At high altitude specific root length is increased by 50% and mean individual rooting density is tripled. Fine root length per unit leaf area is 4.5 times greater (P<0.001). However, interspecific variation in all these quantities is considerable and species with quite contrasting partitioning patterns coexist at both elevations. This suggests that the success of perennial herbaceous plants at high elevations does not necessarily depend on a large below ground biomass fraction. The increased fine root length at high altitude may substitute for reduced mycorrhizal infection. Figure 1 provides a graphical summary.
为了验证与典型低海拔植物相比，高海拔植物会将更多干物质分配到地下部分，特别是储存器官这一假设，我们研究了22种仅生长在低海拔地区和27种仅生长在高海拔地区的多年生草本植物的分配模式。我们的研究结果对这一假设的普遍有效性提出了一些质疑。分配到绿叶中的总干物质平均比例（低海拔地区为22±2%标准误，高海拔地区为24±2%）和特殊储存器官中的总干物质平均比例（两个海拔地区均为28±4%）在不同地点之间没有显著差异。分配到地上植物部分的总干物质平均相对比例在低海拔地区为57±3%，在高海拔地区为42±3%（P = 0.002），差异比通常认为的要小。高海拔地区地下部分比例较大是由于茎的减少和细根部分按比例增加。在高海拔地区，比根长增加了50%，平均个体生根密度增加了两倍。单位叶面积的细根长度大4.5倍（P < 0.001）。然而，所有这些数量的种间变异都相当大，具有截然不同分配模式的物种在两个海拔地区共存。这表明多年生草本植物在高海拔地区的成功并不一定取决于较大的地下生物量比例。高海拔地区增加的细根长度可能替代了减少的菌根感染。图1提供了一个图形总结。
