三种草坪草净光合速率和蒸腾速率的日变化特点研究

A study on the diurnal variation characteristics of net photosynthesis rate and transpiration rate of three species of turfgrasses

研究了在晴天的条件下 ,假俭草、细叶结缕草和地毯草净光合速率和蒸腾速率的日变化特点。结果表明 :( 1)假俭草和细叶结缕草的净光合速率的日变化曲线均为双峰型 ,而地毯草为三峰型 ,3种草出现峰值的时间不同 ,均有明显的“午睡”现象 ,日平均净光合速率的大小顺序为假俭草 >地毯草 >细叶结缕草 ;( 2 )假俭草和细叶结缕草的蒸腾速率的日变化曲线均为双峰型 ,而地毯草为单峰型 ,3种草出现峰值的时间有所差别 ,“午睡”现象均不明显 ,日平均蒸腾速率的大小顺序为细叶结缕草 >地毯草 >假俭草 ;( 3)不同生态因子与 3种草坪草净光合速率、蒸腾速率的相关程度均不相等 ,同种生态因子与不同草坪草的净光合速率、蒸腾速率的相关程度也不一样。

The diurnal variation characteristics of net photosynthesis rate and transpiration rate of Eremochloa ophiuroides, Zoysia tenuifolia and Axonopus compressus in the sunny day were studied. The results showed that the net photosynthesis rate diurnal variation curves of Eremochloa ophiuroides and Zoysia tenuifolia were double peaked, while the curve of Axonopus compressus was three peaked. The peak values of three species of turfgrasses appeared in different times, with an obvious “sleep at noon” phenomenon. The size order of the average value of net photosynthesis rate diurnal variation was E.ophiuroides>A.compressus>E.ophiuroides. The transpiration rate diurnal variation curves of E.ophiuroides and Z.tenuifolia were double peaked, while the curve of A.compressus was single peaked, and their peak value appeared in different times either. Neither of them had an obvious“sleep at noon” phenomenon. The size order of the average value of transpiration rate was Z.tenuifolia>A.compressus>E.ophiuroides. The correlations between different ecological factors and the net photosynthesis rate transpiration rate of 3 species had large difference with each other, and so it did between the same ecological factor and the net photosynthesis rate or transpiration rate of different species.