[A comparative study on photosynthesis and transpiration of Kelimeris integrifolia in summer and autumn on Songnen grasslands of China].

The diurnal changes in photosynthesis and transpiration of Kelimeris integrifolia in Summer and Autumn on Songnen grasslands were characterized as a two-peak curve, but with some differences between two seasons. It was shown that environmental conditions and plant internal factors had a strong effects on plant photosynthesis and transpiration. The net photosynthetic and transpiration rates of the leaves were positively correlated to photosynthetically active radiation (P < 0.01), and negatively correlated to stomatal resistance as well as intercellular CO2 concentration (P < 0.05). The transpiration rate was positively correlated to leaf temperature and water saturation deficit of the air. Among the above factors, photosynthesis active radiation was the dominant factor, and stomatal resistance also played an important role in plant photosynthesis and transpiration.