Chin J Plant Ecol ›› 2022, Vol. 46 ›› Issue (12): 1473-1485.DOI: 10.17521/cjpe.2021.0485

Special Issue: 碳水能量通量

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

Response of ecosystem carbon balance to asymmetric daytime vs nighttime warming in Artemisia ordosica shrublands

HAN Cong1, LIU Peng1,2, MU Yan-Mei1, YUAN Yuan3, HAO Shao-Rong1, TIAN Yun1,2, ZHA Tian-Shan1,2, JIA Xin1,2,*()   

  1. 1Yanchi Research Station, School of Soil and Water Conservation, Beijing Forestry University, Beijing 100083, China
    2Key Laboratory of State Forestry and Grassland Administration on Soil and Water Conservation, Beijing Forestry University, Beijing 100083, China
    3Twenty First Century Aerospace Technology Co., Ltd., Beijing 100096, China
  • Received:2021-12-20 Accepted:2022-04-24 Online:2022-12-20 Published:2023-01-13
  • Contact: *JIA Xin(
  • Supported by:
    National Natural Science Foundation of China(32071843);National Natural Science Foundation of China(32071842);National Natural Science Foundation of China(32101588);National Natural Science Foundation of China(31901366);Fundamental Research Funds for the Central Universities(PTYX202122)


Aims We aimed to explore the response of net ecosystem productivity (NEP) and carbon use efficiency (CUE) to asymmetric daytime vs. nighttime warming in Artemisia ordosica shrublands, and to examine the sensitivity of carbon balance components to daytime vs. nighttime warming.

Methods The BIOME-BGC model was parameterized and validated against eddy covariance measurements of ecosystem carbon fluxes, and used for simulating the impacts of different warming scenarios on NEP and CUE and their components, including gross primary productivity (GPP), net primary productivity (NPP), ecosystem respiration (Re), autotrophic respiration (AR), heterotrophic respiration (HR), maintenance respiration (MR), and growth respiration (GR). Two warming scenarios were simulated: (1) asymmetric warming according to the historical trends from 1954 to 2020 (i.e. daytime warming 1.2 °C, nighttime warming 1.8 °C); (2) daytime or nighttime warming separately with different temperature increase treatments (2, 4, 6 °C).

Important findings (1) Modeled GPP on the daily and annual scales, Re on the daily timescale and NEP on the annual scale showed good agreement with the observed values (coefficient of determination (R2): 0.72-0.88; Nash-Sutcliffe efficiency coefficient (NS): 0.72-0.79). Modeled Re on the annual timescale and NEP on the daily timescale showed weak agreement with observed values (R2: 0.57 and 0.26; NS 0.46 and 0.12, respectively). (2) All warming scenarios promoted GPP, NPP, Re and all respiration components. GPP, Re, AR, and MR were more sensitive to daytime than to nighttime warming, while NPP, HR, GR were more sensitive to nighttime than daytime warming. (3) Greater increases in Re (about 13%) and AR (about 16%) than that in GPP (about 10%) under all warming scenarios, leading to the decreases in NEP and CUE. In addition, both NEP and CUE were more sensitive to daytime than nighttime warming. (4) NEP and CUE decreased by about 68% and 5% under the historical trend of asymmetric daytime vs. nighttime warming treatment. Greater response of NEP and CUE to the daytime warming than nighttime warming. Our results highlight the negative impacts of climatic warming on carbon sink of the semiarid shrublands, and justify the efforts to mitigate climate change are vital for dryland ecosystems.

Key words: net ecosystem productivity, carbon balance, BIOME-BGC, asymmetric warming, daytime warming, nighttime warming, Artemisia ordosica