干旱区生态环境知识资源中心(Arid): Fractional coefficient for estimating physiologically meaningful and diurnal transpiration cycle weighted VPD from daily ambient environmental data

Arid

DOI	10.1016/j.agrformet.2023.109583
	Fractional coefficient for estimating physiologically meaningful and diurnal transpiration cycle weighted VPD from daily ambient environmental data
	Kukal, M. S.; Irmak, S.
通讯作者	Kukal, MS
来源期刊	AGRICULTURAL AND FOREST METEOROLOGY
ISSN	0168-1923
EISSN	1873-2240
出版年	2023
卷号	339
英文摘要	Appropriate representation of environmental conditions via meaningful metrics is critical for their effectiveness in modeling crop physiological and resource use processes. Vapor pressure deficit (VPD) is a primary determinant of crop water use efficiency, commonly reported as daily average. However, VPD can vary substantially during the day in relation to diurnal cycle of transpiration, in which case daily average VPD may not suffice. In such scenarios, integrating VPD over the course of diurnal transpiration cycle into a weighted VPD (VPDw) can be physiologically meaningful as a metric. The goal of this research is to characterize the fractional coefficient (Frac) that can be used to effectively calculate VPDw from daily temperature and relative humidity data without the need for sub-daily environmental data. Site-specific and seasonal estimates of Frac, which represent the relative positioning of VPDw to diurnal extremes of saturation vapor pressure are currently lacking for semi-arid regions. To address this, we quantified Frac at 101 sites in the U.S. Central Plains using long-term (1982-2019) hourly and daily radiation and VPD datasets. Frac varied substantially across the region, with growing season mean values ranging from 0.59 to 0.92. Summer months had the highest Frac values with relatively lower uncertainty as compared to lower Frac during winter. Local observations of Frac deviated significantly from previously assumed stationary estimates implying that site-specific and month-specific Frac may be necessary for robust water use estimations. VPDw measured at an experimental site in Central U.S. Plains explained greater variance in daytime crop transpiration than daily mean VPD in maize, soybean, and sorghum canopies. Sitespecific Frac was also assessed to perform better than commonly used Frac estimate of 0.75 to explain day-today variation in transpiration, demonstrating effective use of long-term mean Frac values presented here to estimate VPDw using daily datasets.
英文关键词	Atmospheric dryness Vapor pressure deficit Evapotranspiration Crop water use
类型	Article
语种	英语
收录类别	SCI-E
WOS记录号	WOS:001023930000001
WOS关键词	VAPOR-PRESSURE DEFICIT ; WATER-USE EFFICIENCY ; RESPONSES ; DROUGHT ; TEMPERATURE ; PHOTOSYNTHESIS ; IRRIGATION ; SOIL
WOS类目	Agronomy ; Forestry ; Meteorology & Atmospheric Sciences
WOS研究方向	Agriculture ; Forestry ; Meteorology & Atmospheric Sciences
资源类型	期刊论文
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/395006
推荐引用方式 GB/T 7714	Kukal, M. S.,Irmak, S.. Fractional coefficient for estimating physiologically meaningful and diurnal transpiration cycle weighted VPD from daily ambient environmental data[J],2023,339.
APA	Kukal, M. S.,&Irmak, S..(2023).Fractional coefficient for estimating physiologically meaningful and diurnal transpiration cycle weighted VPD from daily ambient environmental data.AGRICULTURAL AND FOREST METEOROLOGY,339.
MLA	Kukal, M. S.,et al."Fractional coefficient for estimating physiologically meaningful and diurnal transpiration cycle weighted VPD from daily ambient environmental data".AGRICULTURAL AND FOREST METEOROLOGY 339(2023).