Ehleringer James R
Department of Plant Biology, Carnegie Institution of Washington, 94305, Stanford, CA, USA.
Department of Biological Sciences, Stanford University, 94305, Stanford, CA, USA.
Oecologia. 1978 Jan;31(3):255-267. doi: 10.1007/BF00346246.
The implications of a reduced quantum yield (initial slope of the photosynthetic light response curve) in C plants and temperature dependence of quantum yield in C plants on total canopy primary production were investigated using computer simulations. Since reduced quantum yield represents the only known disadvantage of the C photosynthetic pathway, simulations were conducted with grass canopies (high LAI and hence photosynthesis in most leaves will be light-limited) to see if quantum yield is a significant factor in limiting the primary production and thus distributions of C grasses. Simulations were performed for three biogeographical or environmental conditions: the Great Plains region of North America, the Sonoran Desert of North America, and shade habitats. For all three cases, the simulations predicted either spatial or temporal gradients in the abundances of C grasses identical to the abundance patterns of C grasses observed in the field. It is thus concluded that while the C photosynthetic mechanism may be highly advantageous in specific environments, it may be disadvantageous in others.
利用计算机模拟研究了C4植物量子产率降低（光合光响应曲线的初始斜率）以及C4植物量子产率的温度依赖性对冠层总初级生产力的影响。由于量子产率降低是已知的C4光合途径的唯一缺点，因此对草冠层（叶面积指数高，因此大多数叶片的光合作用将受到光照限制）进行了模拟，以了解量子产率是否是限制初级生产力以及C4草分布的重要因素。针对三种生物地理或环境条件进行了模拟：北美大平原地区、北美索诺兰沙漠和阴凉栖息地。对于所有这三种情况，模拟预测的C4草丰度的空间或时间梯度与在野外观察到的C4草丰度模式相同。因此得出结论，虽然C4光合机制在特定环境中可能非常有利，但在其他环境中可能不利。
