Chin J Plant Ecol ›› 2021, Vol. 45 ›› Issue (2): 119-130.DOI: 10.17521/cjpe.2019.0301

Special Issue: 全球变化与生态系统 生态系统碳水能量通量

• Research Articles • Previous Articles     Next Articles

Characteristics and influencing factors of Bowen ratio variation in typical terrestrial ecosystems in China

HUANG Song-Yu1,2, JIA Xin1,2,3,*(), ZHENG Jia-Jia1,2, YANG Rui-Zhi1,2, MU Yu1,2, YUAN He-Di1   

  1. 1School of Soil and Water Conservation, Beijing Forestry University, Beijing 100083, China
    2Yanchi Ecology Research Station of MU US Desert, Beijing 100083, China
    3Key Laboratory of State Forestry and Grassland Administration on Soil and Water Conservation, Beijing Forestry University, Beijing 100083, China
  • Received:2019-11-06 Accepted:2020-05-12 Online:2021-02-20 Published:2020-06-08
  • Contact: JIA Xin
  • Supported by:
    National Natural Science Foundation of China(31670708);National Natural Science Foundation of China(31670710);National Natural Science Foundation of China(31901366);Fundamental Research Funds for the Central Universities(2015ZCQ-SB-02)

Abstract:

Aims Bowen ratio (β) is an important parameter in land-surface processes. It affects the energy exchange between the surface and the atmosphere. This paper used integrated analyses to investigate the spatial variability and influencing factors of β.
Methods
We collected the published literature on the measurement of surface energy balance by the Eddy Covariance (EC) method carried out in different ecosystem types in China, constructed the database of β and meteorological environment factors and analyzed the difference of β among ecosystems, the spatial variation characteristics of β and its influencing factors.
Important findings (1) The variation of β follows a lognormal distribution. The average β in all ecosystems was 0.95 ± 0.64, the coefficient of variation of β was 67%, the skewness was 1.58, and the kurtosis was 3.07. The shrub ecosystem has the highest mean value (1.26) and the wetland ecosystem has the lowest (0.49). (2) β is significantly different among ecosystems: β of shrub ecosystems is significantly higher than those in grassland, forest and wetland ecosystems, and β of croplands is between grassland ecosystems and forest with wetland ecosystems. (3) β increases with increasing latitude and does not change with longitude and altitude. For every 1° increase in latitude,β increases by 0.038. (4) β decreases with increase in mean annual precipitation (MAP), mean annual temperature (MAT), net radiation (Rn), precipitation of the studied year (PPT), mean temperature of the studied year (Ta), and leaf area index (LAI). (5) There are significant differences in the response of β to biotic and abiotic factors in different ecosystems: β of grassland, forest and shrub ecosystems are sensitive to changes in biotic and abiotic factors, while β of croplands and wetland ecosystems have no correlations with biotic and abiotic factors. (6) MAPand Rn are the direct factors influencing β. MAT affects βindirectly by affecting MAP, Rn and LAI. LAI affects β indirectly by affectingRn. Our results indicate significant effect of the interaction between vegetation types and climatic factors on β. The most important factor affecting energy distribution is precipitation, and the regulation of leaf area on energy distribution is not significant.

Key words: Bowen ratio, latent heat flux, sensible heat flux, ecosystems, energy partitioning, climate, Leaf Area Index