Inferring transpiration from evapotranspiration: A transpiration indicator using the Priestley-Taylor coefficient of wet environment

	Inferring transpiration from evapotranspiration: A transpiration indicator using the Priestley-Taylor coefficient of wet environment
	Gan, Guojing; Liu, Yuanbo
刊名	ECOLOGICAL INDICATORS
	2020
卷号	110
英文摘要	Transpiration (T) from plant tissues is an important variable in ecological and agricultural studies. T is usually estimated using the Priestley-Taylor (PT) equation by an analog to the we environment evaporation (ETw), because vegetation can use water from deep soils. However, the relation between the PT coefficients of T and ETw (alpha(c) and alpha(e)) was still unclear. In this paper, we tested whether alpha(e) can be used as a reasonable indicator of a, at intra-annual and annual scales. We obtained alpha(e) by inverting a complementary relationship model with measured evapotranspiration (ET) at the flux sites and obtained a, after ET was partitioned into evaporation (E) and T. We found that a, tends to converge to alpha(e) at annual scales, and a linear equation can adequately fit the alpha(c) = f(alpha(e)) functions at annual scales. With the alpha(c) = f(alpha(e)) functions determined, satisfactory accuracy (R 2 = 0.89) was achieved in estimating T from ET following the ET -> alpha(e) -> alpha(c) -> T calculating process at annual scales. In comparison, the alpha(c) similar to alpha(e) relationship at 8-day scales are modulated by leaf area index and vapor pressure deficit. However, similar alpha(c) = f(alpha(e)) functions are identified in the region with the same climate type at 8-day scales, indicating that a single alpha(c) = f(alpha(e)) function is applicable in the same region. The accuracy in T predictions at 8 day scales deteriorated compared to those at annual scales. However, R-2 were still larger than 0.58 at most of the sites. Because great progress in ET estimation has been achieved with the help of thermal remote sensing technique in the last two decades, our results here can provide a new method to estimate T from remotely sensed ET.
内容类型	期刊论文
源URL	[http://159.226.73.51/handle/332005/19915]
专题	中国科学院南京地理与湖泊研究所
推荐引用方式 GB/T 7714	Gan, Guojing,Liu, Yuanbo. Inferring transpiration from evapotranspiration: A transpiration indicator using the Priestley-Taylor coefficient of wet environment[J]. ECOLOGICAL INDICATORS,2020,110.
APA	Gan, Guojing,&Liu, Yuanbo.(2020).Inferring transpiration from evapotranspiration: A transpiration indicator using the Priestley-Taylor coefficient of wet environment.ECOLOGICAL INDICATORS,110.
MLA	Gan, Guojing,et al."Inferring transpiration from evapotranspiration: A transpiration indicator using the Priestley-Taylor coefficient of wet environment".ECOLOGICAL INDICATORS 110(2020).