Fig 7. Diurnal variation in sap flow velocity & leaf water potential and relationships with plant-air temperature differences (Tp-Ta) in Artemisia ordosica.

(a) Data from the day on 10 July 2014. (b) A negative relationship between sap flow velocity and Tp-Ta was detected (Sig. probability less than 0.05). (c) Data from the day on the same day with sap flow measurement. (d) A positive relationship between leaf water potential and Tp-Ta was observed (Sig. probability less than 0.05).