气候变化领域集成服务门户(CCPortal): Environmental and biophysical controls on the evapotranspiration over the highest alpine steppe

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DOI	10.1016/j.jhydrol.2015.09.013
	Environmental and biophysical controls on the evapotranspiration over the highest alpine steppe
	Ma, Ning; Zhang, Yinsheng; Guo, Yanhong; Gao, Haifeng; Zhang, Hongbo; Wang, Yefan
通讯作者	Ma, N (通讯作者)
发表日期	2015
ISSN	0022-1694
EISSN	1879-2707
起始页码	980
结束页码	992
卷号	529
英文摘要	Characterizing the water and energy flux in the alpine steppe ecosystem in Tibetan Plateau (TP) is of particular importance for elucidating hydrological cycle mechanisms in high altitude areas. In the present study, two years of actual evapotranspiration (ET) values from a semi-arid alpine steppe region (4947 m above sea level) and their environmental and biophysical controls were investigated using the energy balance Bowen ratio energy balance (BREB) method. Seasonally, ET was much lower in frozen soil period and transition period mainly because of low soil water availability. However, ample soil water supplied by rainfall during the rainy period substantially increased ET. The available energy played an important role in controlling ET in the rainy period. Also, the leaf-level stomata closure and plant leaf development could impact the ET through changing bulk surface conductance (G(s)) in rainy period. Similarly, the land-atmosphere energy exchange was dominated by latent heat flux (lambda E) in July, but was dominated by sensible heat flux (H) in December and May. Annual ET (plus sublimation) were 362.9 mm and 353.4 mm in the first and second observation year, respectively, which were close to the annual precipitation. On annual scale, the low G(s) (3.30-3.62 mm s(-1)), decoupling factor (Omega, 0.25-0.27) and the ratio of ET to equilibrium evapotranspiration (ET/ETeq, 0.34-0.35) corroborated the overall water-limited conditions for the high-altitude alpine steppe. This research provides not only the ground truth data for future hydrological modeling in the data scarce region of TP but also the insights for elucidating how the environmental and biophysical stress factors control the land surface ET in high-altitude region. (C) 2015 Elsevier B.V. All rights reserved.
关键词	SURFACE-ENERGY FLUXES WATER-VAPOR EXCHANGE TIBETAN PLATEAU DECIDUOUS FOREST INNER-MONGOLIA INTERANNUAL VARIATION SPARSE GRASSLAND USE EFFICIENCY BALANCE METHOD LONG-TERM
英文关键词	Evapotranspiration; Bulk surface conductance; Decoupling factor; Alpine steppe; Tibetan Plateau
语种	英语
WOS研究方向	Engineering ; Geology ; Water Resources
WOS类目	Engineering, Civil ; Geosciences, Multidisciplinary ; Water Resources
WOS记录号	WOS:000364249500024
来源期刊	JOURNAL OF HYDROLOGY
来源机构	中国科学院青藏高原研究所
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/258451
推荐引用方式 GB/T 7714	Ma, Ning,Zhang, Yinsheng,Guo, Yanhong,et al. Environmental and biophysical controls on the evapotranspiration over the highest alpine steppe[J]. 中国科学院青藏高原研究所,2015,529.
APA	Ma, Ning,Zhang, Yinsheng,Guo, Yanhong,Gao, Haifeng,Zhang, Hongbo,&Wang, Yefan.(2015).Environmental and biophysical controls on the evapotranspiration over the highest alpine steppe.JOURNAL OF HYDROLOGY,529.
MLA	Ma, Ning,et al."Environmental and biophysical controls on the evapotranspiration over the highest alpine steppe".JOURNAL OF HYDROLOGY 529(2015).