植物生态学报 ›› 2021, Vol. 45 ›› Issue (11): 1191-1202.DOI: 10.17521/cjpe.2021.0106

所属专题: 碳水能量通量

• 研究论文 • 上一篇    下一篇

北京松山落叶阔叶林生态系统水热通量对环境因子的响应

李鑫豪1, 田文东2, 李润东1, 靳川1, 蒋燕1, 郝少荣1, 贾昕1,3, 田赟1,3, 查天山1,3,*()   

  1. 1北京林业大学水土保持学院, 北京 100083
    2北京市房山区林果科技服务中心, 北京 102488
    3北京林业大学水土保持国家林业局重点实验室, 北京 100083
  • 收稿日期:2021-03-23 接受日期:2021-05-24 出版日期:2021-11-20 发布日期:2021-06-28
  • 通讯作者: 查天山
  • 作者简介:* (tianshanzha@bjfu.edu.cn)
  • 基金资助:
    国家重点研发计划(2020YFA0608100);中央高校基本科研业务费(2015ZCQ-SB-02)

Responses of water vapor and heat fluxes to environmental factors in a deciduous broad- leaved forest ecosystem in Beijing

LI Xin-Hao1, TIAN Wen-Dong2, LI Run-Dong1, JIN Chuan1, JIANG Yan1, HAO Shao-Rong1, JIA Xin1,3, TIAN Yun1,3, ZHA Tian-Shan1,3,*()   

  1. 1School of Soil and Water Conservation, Beijing Forestry University, Beijing 100083, China
    2Forestry and Fruit Technology Service Center of Fangshan, Beijing 102488, China
    3Key Laboratory of State Forestry Administration on Soil and Water Conservation, Beijing Forestry University, Beijing 100083, China
  • Received:2021-03-23 Accepted:2021-05-24 Online:2021-11-20 Published:2021-06-28
  • Contact: ZHA Tian-Shan
  • Supported by:
    National Key R&D Program of China(2020YFA0608100);Fundamental Research Funds for the Central Universities(2015ZCQ-SB-02)

摘要:

温带森林生态系统水热通量在多时间尺度上受各种生物物理因子的影响。该研究假设这些因子对水热通量的影响机制具有时间尺度分异性, 通过涡度相关法(EC)于2019年全年对北京松山典型天然落叶阔叶林生态系统蒸散发(ET)、显热通量(H)、潜热通量(LE)、土壤热通量(G)、饱和水汽压差(VPD)、空气温度(Ta)、光合有效辐射(PAR)、归一化植被指数(NDVI)及10 cm深度土壤水分(VWC)等要素进行原位连续监测, 使用小波分析的方法分析了日、季节尺度上生物与非生物因子对生态系统能量分配与水汽交换的调控机制。主要研究结果: 2019年松山天然落叶阔叶林生态系统年均波文比(β)为1.53。ET具有明显的季节变化特征, 从第100天开始逐渐增加, 7月达到峰值, 第300天下降到最低水平。ET最大日累计值为5.01 mm·d-1, 年累计值为476.2 mm, 年降水量为503.3 mm。在日尺度上水热通量与VPD间滞后时间最短, 为3.36 h。在季节尺度上与PAR间滞后时间最短, 为8天。季节尺度上PAR通过VPD来对ET造成间接影响, 而对β造成直接影响。该研究发现不同时间尺度上水热通量与环境因子间的时滞关系, 为选择模型在不同时间尺度下北方温带落叶阔叶林生态系统过程的最佳输入参数提供科学支持。

关键词: 蒸散发, 能量交换, 小波分析, 落叶阔叶林

Abstract:

Aims The responses of water and heat fluxes of temperate forest ecosystems to environmental factors are hypothesized to vary with time scales. This study aimed to examine the variations of water and heat fluxes in a typical natural deciduous broad-leaved forest ecosystem in Songshan and their response mechanisms to environmental factors at different time scales.
Methods The eddy-covariance (EC) method was used to continuously monitor the evapotranspiration (ET), sensible heat (H), latent heat (LE), soil heat flux (G), vapor pressure deficit (VPD), air temperature (Ta), photosynthetically active radiation (PAR), normalized difference vegetation index (NDVI), and soil water content at a depth of 10 cm (VWC) in a typical deciduous broad-leaved forest ecosystem in Songshan, Beijing in 2019. The wavelet analysis was used to examine the regulation mechanism of biotic and abiotic factors on energy distribution and water vapor exchange at different time scales.
Important findings The mean annual Bowen ratio (β) was 1.53 in 2019. ET had obvious seasonal dynamics, increasing gradually from day 100, peaking in July, and decreasing to the lowest level on day 300. The maximum daily evapotranspiration was 5.01 mm·d-1, the cumulative annual evapotranspiration was 476.2 mm, and the cumulative annual rainfall was 503.3 mm. The main influencing factors of the water and heat fluxes varied with time scales, being mostly controlled by VPD at the daily scale, and by PAR at the seasonal scale. At the diurnal scale, water and heat fluxes lagged 3.36 h behind VPD. At the seasonal scale, water and heat fluxes lagged 8 days behind PAR. At the seasonal scale, PAR had an indirect impact on ET through its effects on VPD and a direct impact on β. The results indicate the time-delay relationships between water and heat fluxes and environmental factors at different time scales, which provides support for selecting the optimal input parameters of the models for quantitatively forecasting ecosystem processes at different time scales in northern temperate deciduous broad-leaved forests.

Key words: evapotranspiration, energy exchange, wavelet analysis, deciduous broad-leaved forest