Chin J Plant Ecol ›› 2023, Vol. 47 ›› Issue (11): 1585-1599.DOI: 10.17521/cjpe.2022.0244

• Research Articles • Previous Articles     Next Articles

Effects of precipitation variations on characteristics of sap flow and water source of Platycladus orientalis

ZHANG Xiao1, WU Juan-Juan1, JIA Guo-Dong1,2,*(), LEI Zi-Ran1, ZHANG Long-Qi1, LIU Rui1, LÜ Xiang-Rong1, DAI Yuan-Meng1   

  1. 1School of Soil and Water Conservation, Beijing Forestry University, Beijing 100083, China
    2Key Laboratory of Soil and Water Conservation and Desertification Control, Ministry of Education, Beijing 100083, China
  • Received:2022-06-10 Accepted:2022-12-03 Online:2023-11-20 Published:2023-12-22
  • Contact: JIA Guo-Dong(
  • Supported by:
    National Natural Science Foundation of China(42277062);National Natural Science Foundation of China(42230714)


Aims Seasonal drought often occurs in the northern rocky mountainous area due to annual variation in precipitation. Exploring the effects of changes in precipitation on the sap flow characteristics and water sources of Platycladus orientalis is of great significance for structuring a stable ecosystem.

Methods In this study, the plantation of P. orientalis in the rocky mountainous area of Beijing was taken as the research target. The thermal dissipation probe (TDP) and hydrogen/oxygen isotope tracer technology were used to observe the P. orientalisunder different watering treatments. Meteorological, soil moisture, and other environmental factors were simultaneously monitored.

Important findings The results showed that natural precipitation and double precipitation > half precipitation > no precipitation were the main characteristics of P. orientalis sap flow. Precipitation increased the relative effective water content (REW) of soil, thereby stimulated the response of P. orientalis sap flow to environmental factors. Platycladus orientalis sap flow is mainly affected by the atmospheric vapor pressure deficit (VPD), and the impact of solar radiation (Rs) and wind speed (WS) is relatively low. The water source of P. orientalis changed with precipitation amounts. When the soil water content increased, its water source gradually changed to shallow soil. Compared with precipitation before, P. orientalis have increased the utilization ratio of 0-40 cm soil water after precipitation, except that P. orientalis in no precipitation treatment that exhibited no noticeable change. This change is more pronounced in natural precipitation and double precipitation treatments where a period of high relative water content after precipitation was more evident. To sum up, P. orientalis can adjust sap flow and the depth of water absorption from soil in responses to the changes in precipitation and soil moisture. This self-adaptive characteristic is conducive for trees to survive the extreme drought.

Key words: tree sap flow, precipitation variation, water source, environmental factor