黄土高原芨芨草光合与蒸腾作用的初步研究

Initial study on the leaf photosynthesis and transpiration of Achnatherum splendens on the Loess Plateau

对芨芨草叶片的生理生态特性进行了初步分析,结果表明,1)芨芨草叶片光合速率日进程受环境影响,在不同时期差异较大,6、7月呈双峰曲线,8月和9月,光合速率则呈单峰曲线;芨芨草蒸腾速率和气孔导度日进程在整个生育期内基本上呈单峰曲线。2)回归分析和相关分析表明,不同时期对芨芨草叶片光合速率、蒸腾速率和气孔导度起决定性作用的环境因子不同,而在整个生育期它们三者之间都存在着极显著的正相关关系。

An initial study was carried out on the ecophysiological leaf characteristics of Achnatherum splendens. Due to environmental influence, daily variation in leaf photosynthetic rate of A. splendens differed in different months. This change is represented as two-peaked curves for June and July, and single-peaked curves for August and September. The daily variation in transpiration rate and stomatal conductance over the whole growth and development period can basically be represented by single-peaked curves. Regression and correlation analyses showed that in different months the deciding environmental factors influencing photosynthetic rate, transpiration rate, and stomatal conductance were different; but that for the whole growth and development period, these three leaf characteristics were very significantly, positively correlated.