苗期红豆草光合速率日变化及其影响因子分析

为探明红豆草光合特征及影响红豆草光合作用的主要环境因子,在盆栽条件下用LI-6400型光合作用系统,对苗期红豆草叶片光合特征及环境因子的日变化进行了观测,并采用相关系数和多元逐步回归分析方法分析各环境因子对苗期红豆草光合速率的影响。结果表明,苗期红豆草光合速率日变化呈单峰曲线,峰值出现在正午12:00左右,约为27.63μmol/(m2.s),日平均值为22.33μmol/(m2.s);相关分析表明,光合有效辐射是直接影响红豆草光合速率日变化的主要环境因子,与光合速率呈极显著正相关关系。

Daily Variation of Photosynthetic Rate and Its Influence Factors on Onobrychis Viciaefolia Seedlings

In order to investigate the photosynthetic characteristics of Onobrychis viciaefolia seedlings and the main environmental factors directly influencing photosynthesis of the seedlings,the photosynthetic characteristics of Onobrychis viciaefolia seedlings and the diurnal variations of the factors were measured using Li-6400 photosynthesis system by a pot experiment.Meanwhile,the effects of the factors on photosynthetic rate(Pn) were analyzed using correlation analysis and stepwise multi-regression analysis.Results showed that the diurnal variation of the Pn presented a feature of single peak curve with its peak value appearing at 12:00 am,about 27.63 μmol/(m2·s).The daily average Pn over the observation time was calculated to be 22.33 μmol/(m2·s).Besides,according to correlation analysis,photosynthetically active radiation(PAR) was found to be the main environmental factor directly influencing the daily Pn of Onobrychis viciaefolia seedlings and the PAR had a highly significant positive correlation with the Pn.