Chin J Plant Ecol ›› 2023, Vol. 47 ›› Issue (10): 1422-1431.DOI: 10.17521/cjpe.2022.0317

Special Issue: 光合作用

• Research Articles • Previous Articles     Next Articles

Response of xylem hydraulic conductivity and leaf photosynthetic capacity of sand-binding shrubs Caragana korshinskii and C. liouana to soil water

ZHANG Zhi-Shan1, HAN Gao-Ling1,2, HUO Jian-Qiang1,2,*(), HUANG Ri-Hui3, XUE Shu-Wen3   

  1. 1Shapotou Desert Research and Experiment Station, Northwest Institute of Eco-Environmental Resources, Chinese Academy of Sciences, Lanzhou 730000, China
    2University of Chinese Academy of Sciences, Beijing 100049, China
    3School of Geographical Sciences, Lingnan Normal University, Zhanjiang, Guangdong 524036, China
  • Received:2022-07-27 Accepted:2023-02-15 Online:2023-10-20 Published:2023-03-01
  • Contact: * (huojq3061@163.com)
  • Supported by:
    Major Science and Technology Projects of Nei Mongol Autonomous Region(2021ZD0008-3);National Natural Science Foundation of China(31971529);National Natural Science Foundation of China(32301314)

Abstract:

Aims Water is the main limiting factor for revegetation and ecorestrotion in arid sandy areas. Soil available water content directly affects the xylem water transport capacity of plant. However, the differences in xylem hydraulic traits and leaf gas exchange of different shrub species with different ages under varied soil water content are still unclear.

Methods The 10-year-old and 30-year-old Caragana korshinskii and C. liouana in the sand-binding area were employed to explore the differences and relationships between their hydraulic traits and photosynthetic traits during the dry and rainy season.

Important findings The results showed that the shrub age has no significant effect on xylem hydraulic conductivity, degree of natural embolism, leaf water potential and relative water content of C. korshinskii and C. liouana, while soil water content significantly effects on these functional traits. Both shrub age and soil water content have significant effects on leaf photosynthesis of two shrub species, but the effect of shrub age on them is little significant during the rainy season. In addition, there was a significant positive linear relationship between soil water content with leaf water content and xylem-stem specific hydraulic conductivity. Xylem hydraulic conductivity also had a significant positive correlation with leaf water content and stomatal conductance, whereas net photosynthetic rate was also positive related to xylem hydraulic conductivity and leaf water content. Results indicated that soil water content directly affected leaf water status and the capacity of photosynthetic carbon assimilation by affecting xylem hydraulic conductivity and embolization degree. In conclusion, the change of soil water content significantly affected the xylem hydraulic conductivity and leaf photosynthetic carbon assimilation capacity of C. caraganaand C. Liouana.

Key words: sand-binding shrub, xylem hydraulic conductivity, photosynthetic traits, water effect size, arid areas