Energy balance and partitioning over grasslands on the Mongolian Plateau

Ecological Indicators

Luping Qu¹  Tsegaye Gemechu Legesse²  Shicheng Jiang³  Gang Dong⁴  Fangyuan Zhao⁵  Changliang Shao⁶  Qi Tong⁷  Xingguo Han⁸  Jiquan Chen⁹  Jingyan Chen^1,10 

[1] Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing 100081, China;Institute of Loess Plateau, Shanxi University, Taiyuan 030006, China;;National Hulunber Grassland Ecosystem Observation and Research Station &State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China;Department of Geography, Environment, and Spatial Sciences, Michigan State University, East Lansing 48824, USA;Forestry College, Fujian Agriculture and Forestry University, Fuzhou 350002, China;Key Laboratory of Vegetation Ecology, Ministry of Education, Northeast Normal University, Changchun 130024, China;;National Hulunber Grassland Ecosystem Observation and Research Station &School of Life Science, Shanxi University, Taiyuan 030006, China;University of Chinese Academy of Sciences, Beijing 100049, China;

关键词: Vegetation dynamics;    Evapotranspiration;    Sensible heat;    Eddy covariance;    Steppe;   

DOI  :  

来源: DOAJ

【 摘 要 】

Energy flux is a key component and driving factor in ecosystem processes and functions. Using 2015 datasets of eddy covariance, vegetation and meteorological measurements at four dominant ecosystems on the Mongolian Plateau, we analyzed the inter-site and seasonal variations and underlying biophysical controls on energy balance and partitioning in a meadow steppe (MDW), typical steppe (TPL), dry typical steppe (DRT) and shrubland (SHB). Vegetation dynamics dominated the energy partitioning. The growing season (May-Sept) net radiation (Rn) was 20% less at SHB due to higher bare soil coverage area than that at MDW. High vegetation cover and soil water content resulted in the highest latent heat (LE) at MDW, while sparse vegetation showed the highest sensible heat (H) at DRT among the four vegetation types. The Bowen ratios (β, H/LE) at TPL (1.68), DRT (1.44) and SHB (1.44) were an order of magnitude higher than that at MDW (0.14). At DRT and SHB, β had significantly negative feedback on canopy conductance (p < 0.05) and significantly positive feedback on vapor pressure deficit (VPD) (p < 0.05). We emphasized that the complex, interactive effects of vegetation types, ecosystem structures, and microclimate for the energy balance and partitioning.

【 授权许可】

Unknown