棉花阴、阳叶的气孔导度和光合作用观测对比及模型应用

Comparison of the Stomatal Conductance and Photosynthetic Rate of Cotton's Sunlit and Shaded Leaves,and Application of Photosynthesis Model

以实验观测数据为基础,对棉花阳叶和阴叶光合速率、气孔导度的变化进行比较,通过双叶模型和大叶模型对冠层光合作用进行对比分析,结果表明,大叶模型的计算结果普遍高于双叶模型,总体高出13%。由此可见,过去在研究植被—大气碳交换中使用大叶模型估算植物光合作用会夸大碳汇的作用。

Based on observed data, we compare the photosynthetic rate and stomatal conductance of sunlit and shaded cotton leaves respectively. Results show that the photosynthesis in big-leaf model is totally 13% higher than that in two-leaf model. Therefore, the contribution of cotton＇s potosynthesis to carbon sink might be exaggerated in past estimating photosynthesis by using big-leaf model in carbon exchanges between the biosphere and the atmosphere.