【摘要】 本文从叶片和冠层尺度入手，采用手持式光合仪和涡动相关法，分析确定C3作物春小麦和冬小麦气体交换模型关键参数随季节变化的特征。结果表明：春小麦叶片尺度最大羧化速率和最大电子传递速率在生育末期快速减小，其他阶段差异不显著，但二者之比随发育期变化相对稳定，均值为2.2;春小麦生长季叶片气孔导度模型斜率在9～11间变动，均值为9.7。冬小麦冠层尺度最大羧化速率和最大电子传递速率随发育期呈抛物线变化，但二者之比相对稳定，均值为1.43;冬小麦冠层导度模型斜率在不同年份不同季节变化无明显规律，整个生育期围绕均值12波动。本研究论证了表征作物光合能力的参数随生育期变化以及气孔导度模型斜率相对稳定的特征。可为陆气相互作用过程分析以及生态系统碳—水循环模拟提供参数化依据。更多还原

【Abstract】 Starting from the scales of leaves and canopies, this article uses handheld photosynthetic instruments and eddy correlation methods to analyze and determine the seasonal variation characteristics of key parameters in the gas exchange models of C3 crops for spring and winter wheat. Results show that the maximum carboxylation rate and maximum electron transfer rate at the leaf scale of spring wheat decrease rapidly in the late growth stage, with no significant differences in other stages. However, the ratio of the two remained relatively stable with the development period, with an average of 2.2. The slope of the stomatal conductance model for spring wheat leaves during the growing season varies between 9 and 11, with a mean of 9.7. The maximum carboxylation rate and maximum electron transfer rate at the canopy scale of winter wheat exhibit parabolic changes with the development period, but the ratio of the two is relatively stable, with an average of 1.43; the slope of the winter wheat canopy conductance model shows no significant variation in different years and seasons, and fluctuates around the mean of 12 throughout the entire growth period. In this study, the seasonal variation of the parameters that characterize the photosynthetic capacity of crops is demonstrated, and the slope of the stomatal conductance model is relatively stable. This study demonstrates the variation of parameters that characterize crop photosynthetic capacity with growth period and the relatively stable slope of stomatal conductance model. It can provide parameterized basis for the analysis of land atmosphere interaction process and simulation of ecosystem carbon water cycle.更多还原