Chin J Plant Ecol ›› 2022, Vol. 46 ›› Issue (12): 1508-1522.DOI: 10.17521/cjpe.2022.0099

Special Issue: 全球变化与生态系统 生态系统碳水能量通量

• Special feature: Ecosystem carbon and water fluxes in ecological vulnerable areas of China • Previous Articles     Next Articles

Energy flux and evapotranspiration of two typical plantations in semi-arid area of western Liaoning, China

WANG Li-Shuang1, TONG Xiao-Juan1,*(), MENG Ping2, ZHANG Jin-Song2, LIU Pei-Rong1, LI Jun3, ZHANG Jing-Ru1, ZHOU Yu2   

  1. 1School of Ecology and Nature Conservation, Beijing Forestry University, Beijing 100083, China
    2Research Institute of Forestry, Chinese Academy of Forestry, Beijing 100091, China
    3Key Laboratory of Water Cycle and Related Land Surface Processes, Institute of Geographical Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China
  • Received:2022-03-18 Accepted:2022-06-15 Online:2022-12-20 Published:2023-01-13
  • Contact: *TONG Xiao-Juan(
  • Supported by:
    National Key R&D Program of China(2020YFA0608101);National Natural Science Foundation of China(31872703);National Natural Science Foundation of China(31570617)


Aims Under the background of climate warming, the contradiction between forest and water in semi-arid areas is becoming increasingly prominent. Understanding the changes in energy flux and evapotranspiration (ET) of the plantation ecosystems in this area can provide a reference for future selection of afforestation tree species.

Methods In this paper, the water and heat fluxes of Pinus tabuliformis and Pinus sylvestris var. mongolica plantations in semi-arid area of western Liaoning were observed continuously for one year (October 2019 to October 2020) using the eddy covariance method. The length of growing season (April 11 to October 10) was determined using the critical temperature combined with the variation characteristics of normalized differential vegetation index (NDVI). The seasonal dynamics of latent heat flux (LE), sensible heat flux (H), net radiation (Rn), soil heat flux (G) and ET were analyzed. The effects of air temperature (Ta), Rn, vapor pressure deficit (VPD), soil water content (SWC), and NDVI on ET were discussed by applying regression analysis and path analysis.

Important findings The Rn, G and H of P. tabuliformis and P. sylvestrisvar. mongolica plantations showed single-peak seasonal variation trends, and the seasonal dynamics of LE fluctuated more sharply. During the whole year, energy consumption was dominated by H, followed by LE, and G consumed less energy. The average values of Bowen ratio during the growing season were 1.82 and 2.23, respectively, smaller than annual average values (3.43 and 4.44). The ET during the growing season was 302.79 and 247.54 mm, accounting for 82.89% and 84.20% of the annual ET, respectively. The annual ET was 365.29 and 293.99 mm accounting for 87.81% and 72.23% of precipitation in the same period. Priestley-Taylor coefficient (α) and decoupling factor (Ω) were used to analyze the effects of SWC and canopy conductance (gc) on ET. The annual mean values ​​of α was 0.30 and 0.24, respectively, and the Ω values was 0.12 and 0.07, respectively. During the whole year, SWC was the dominant factor affecting the ET of two plantations, followed by Rn. Under non-water-stressed conditions, Rn had a greater impact on ET.The combined effects of Ta and VPD on ET were small, which were mostly indirect effects. NDVI and gc were important biological factors affecting the ET of the two plantations, especially during the growing season. This study shows that P. tabuliformis and P. sylvestrisvar. mongolica plantations in the semi-arid area of western Liaoning Province adopt a conservative water consumption strategy to maintain water balance of the ecosystem, and these species are suitable afforestation tree species in this area.

Key words: semi-arid region, plantation, energy flux, evapotranspiration, bioenvironmental factor