植物生态学报 ›› 2022, Vol. 46 ›› Issue (12): 1473-1485.DOI: 10.17521/cjpe.2021.0485

所属专题: 碳水能量通量

• 中国典型生态脆弱区碳水通量过程研究专题论文 • 上一篇    下一篇

黑沙蒿灌丛生态系统碳平衡对昼夜非对称增温的响应

韩聪1, 刘鹏1,2, 母艳梅1, 原媛3, 郝少荣1, 田赟1,2, 查天山1,2, 贾昕1,2,*()   

  1. 1北京林业大学水土保持学院, 宁夏盐池毛乌素沙地生态系统国家定位观测研究站, 北京 100083
    2北京林业大学水土保持国家林业和草原局重点实验室, 北京 100083
    3二十一世纪空间技术应用股份有限公司, 北京 100096
  • 收稿日期:2021-12-20 接受日期:2022-04-24 出版日期:2022-12-20 发布日期:2023-01-13
  • 通讯作者: *贾昕(xinjia@bjfu.edu.cn)
  • 基金资助:
    国家自然科学基金(32071843);国家自然科学基金(32071842);国家自然科学基金(32101588);国家自然科学基金(31901366);中央高校基本科研业务费专项资金(PTYX202122)

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(xinjia@bjfu.edu.cn)
  • 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)

摘要:

探究黑沙蒿(Artemisia ordosica)灌丛净生态系统生产力(NEP)和碳利用效率(CUE)对昼夜非对称增温的响应, 揭示碳平衡各组分对日间或夜间增温的相对敏感性, 对于预测此类生态系统在气候变化条件下的碳源/汇属性及固碳能力是十分必要的。该研究基于涡度协方差观测数据进行模型参数化和验证, 采用BIOME-BGC模型模拟不同增温情景, 检验非对称增温如何影响NEP、CUE及其组分, 包括: 总初级生产力(GPP)、生态系统呼吸(Re)、自养呼吸(AR)、异养呼吸(HR)、维持呼吸(MR)、生长呼吸(GR)、净初级生产力(NPP)等。非对称增温方式包括: (1)延续历史升温趋势(1954-2020年)的昼夜非对称增温(日间增温1.2 ℃, 夜间增温1.8 ℃); (2)日间或夜间单独增温(2、4、6 ℃)。主要结果: (1)与观测值拟合关系较好的指标包括GPP的逐日值和逐年值、Re的逐日值以及NEP的逐年值(决定系数: 0.72-0.88; 效率系数: 0.72-0.79), 拟合关系相对较弱的指标包括Re的逐年值和NEP的逐日值(决定系数: 0.57、0.26; 效率系数: 0.46、0.12)。(2)所有增温情景对GPP、Re及其组分、NPP均呈促进作用。其中, GPP、Re、AR、MR对日间增温比对夜间增温更为敏感; NPP、HR、GR则对夜间增温更敏感。(3)在所有增温情景下, Re (约13%)和AR (约16%)的增幅均比GPP (约10%)更大, 因此NEP和CUE呈下降趋势。并且NEP和CUE均对日间增温更敏感。(4) NEP和CUE在昼夜非对称增温情景分别下降了约68%和5%, 对日间增温下降的幅度比夜间分别高约8%和1%。尽管有区域或全球尺度的研究认为增温会提高生态系统碳汇能力, 但该研究结果表示增温抑制半干旱地区碳汇能力, 这表明当前为减缓全球变暖所付出的努力是必要的。

关键词: 净生态系统生产力, 碳平衡, BIOME-BGC, 非对称增温, 日间增温, 夜间增温, 黑沙蒿

Abstract:

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