Körner Ch, Farquhar G D, Roksandic Z
Institut für Botanik, Sternwartestraße 15, A-6020, Innsbruck, Austria.
Plant Environmental Biology, Research School of Biological Sciences, Australian National University, G.P.O. Box 475, 2601, Canberra, A.C.T., Australia.
Oecologia. 1988 Jan;74(4):623-632. doi: 10.1007/BF00380063.
Carbon 13/12 isotope ratios have been determined from leaves of a hundred C plant species (or ecotypes) from all major mountain ranges of the globe, avoiding drought stressed areas. A general increase in C content was found with increasing altitude, i.e. overall discrimination against the heavy isotope is reduced at high elevation. The steepest decline of discrimination is observed in taxa typically ranging to highest elevations (e.g. the genus Ranunculus). Mean δ C for all samples collected between 2500 and 5600 m altitude is-26.15‰ compared to the lowland average of-28.80‰ (P<0.001). Forbs from highest elevations reach-24‰. According to theory of C discrimination this indicates decreasing relative limitation of carbon uptake by carboxylation. In other words, we estimate that the ratio of internal to external partial pressure of CO (p /p )in leaves of high elevation plants is lower than in leaves of low altitude. These results confirm recent gas exchange analyses in high and low elevation plants.
已对全球所有主要山脉（避开干旱胁迫地区）的100种C植物物种（或生态型）的叶片进行了碳13/12同位素比率测定。研究发现，随着海拔升高，碳含量普遍增加，即在高海拔地区对重同位素的总体歧视减少。在通常分布于最高海拔的分类群（如毛茛属）中，观察到歧视下降最为陡峭。海拔2500至5600米之间采集的所有样本的平均δC为-26.15‰，而低地平均值为-28.80‰（P<0.001）。来自最高海拔的草本植物达到-24‰。根据碳歧视理论，这表明羧化作用对碳吸收的相对限制在降低。换句话说，我们估计高海拔植物叶片中CO的内部与外部分压之比（p /p ）低于低海拔植物叶片。这些结果证实了最近对高海拔和低海拔植物进行的气体交换分析。
