干旱区生态环境知识资源中心(Arid): Intermittency of water vapor fluxes from vineyards during light wind and convective conditions

Arid

DOI	10.1007/s00271-018-0617-5
	Intermittency of water vapor fluxes from vineyards during light wind and convective conditions
	Los, Sebastian A.1; Hipps, Lawrence E.1; Alfieri, Joseph G.2; Kustas, William P.2; Prueger, John H.3
通讯作者	Los, Sebastian A.
来源期刊	IRRIGATION SCIENCE
ISSN	0342-7188
EISSN	1432-1319
出版年	2019
卷号	37 期号:3 页码:281-295
英文摘要	Vineyards in many semi-arid regions globally face limited water resources. Monitoring evapotranspiration (ET) of vineyards is critical for water resource management, but remains difficult due to the complex biophysics of the surfaces. Both measurement and modeling approaches for estimating turbulent water vapor transport rely on implicit assumptions that exchanges occur in a reasonably regular fashion over the time scales generally used for averaging. However, heterogeneous vegetation in semi-arid climates, such as many vineyards, presents inherent factors, including canopy row/row space structure and frequent periods of light wind, unstable conditions, that can create episodic transport characteristics. Eddy covariance data were collected above and within the canopy of two vineyards in the Central Valley of California during the Grape Remote sensing Atmospheric Profile & Evapotranspiration eXperiment (GRAPEX). The goal was to document and quantify the existence of intermittent turbulence transport of water vapor, and associated episodic canopy venting. These effects were found to correlate with periods light winds and highly unstable/convective conditions. Power and cross-spectra for intermittent periods documented enhancement of low-frequency water vapor exchange events compared to more steady periods, and diminished time scale correlation between humidity within the canopy and above the canopy. Analyses show that intermittent cases can necessitate longer flux-averaging periods (up to 2h) than more steady conditions. Episodic exchange events were isolated and summed to determine their relative contribution to the overall water vapor flux. Since light wind, unstable conditions are relatively common in many arid vineyard regions, these findings have implications for mechanistic ET models that rely on time-averaged vertical gradients, which implies reasonably steady transport.
类型	Article
语种	英语
国家	USA
开放获取类型	Green Accepted
收录类别	SCI-E
WOS记录号	WOS:000469391800006
WOS关键词	ENERGY FLUXES ; TURBULENCE ; EVAPOTRANSPIRATION ; HEAT ; FLOW
WOS类目	Agronomy ; Water Resources
WOS研究方向	Agriculture ; Water Resources
资源类型	期刊论文
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/216562
作者单位	1.Utah State Univ, Dept Plants Soils & Climate, 4820 Old Main Hill, Logan, UT 84322 USA; 2.USDA ARS, Hydrol & Remote Sensing Lab, Bldg 007,Rm 104, Beltsville, MD 20705 USA; 3.USDA ARS, Natl Lab Agr & Environm, 2110 Univ Blvd Ames, Beltsville, IA 50011 USA
推荐引用方式 GB/T 7714	Los, Sebastian A.,Hipps, Lawrence E.,Alfieri, Joseph G.,et al. Intermittency of water vapor fluxes from vineyards during light wind and convective conditions[J],2019,37(3):281-295.
APA	Los, Sebastian A.,Hipps, Lawrence E.,Alfieri, Joseph G.,Kustas, William P.,&Prueger, John H..(2019).Intermittency of water vapor fluxes from vineyards during light wind and convective conditions.IRRIGATION SCIENCE,37(3),281-295.
MLA	Los, Sebastian A.,et al."Intermittency of water vapor fluxes from vineyards during light wind and convective conditions".IRRIGATION SCIENCE 37.3(2019):281-295.