A novel segmental model to describe the complete soil water retention curve from saturation to oven dryness

doi:10.1016/j.jhydrol.2020.124649

	A novel segmental model to describe the complete soil water retention curve from saturation to oven dryness
	Du, Chaoyang 1,2
刊名	JOURNAL OF HYDROLOGY
	2020-05-01
卷号	584 页码:10
关键词	Water retention curve Full range Oven-dryness Segmental models
ISSN号	0022-1694
DOI	10.1016/j.jhydrol.2020.124649
通讯作者	Du, Chaoyang(ducy@igsnrr.ac.cn)
英文摘要	Traditional water retention models that use the residual water content parameter fail to accurately describe the dry end of the soil water retention curve (SWRC). We developed two- and three-segment smooth, continuous SWRC models, acknowledging the existence of three saturation states, for water contents ranging from saturation to oven-dryness. The equations near the oven dryness end in both models were obtained based on the assumption of proportionality between the soil water content and the logarithm of suction. The equations in the wet range for both models were modified from the van Genuchten model and/or Brook-Corey model(s) by removing the residual water content parameter. The continuity and smoothness conditions at the junction points reduced the fitting parameters of the three- and two- segment models from 9 to 4 and from 6 to 3, respectively. Both models were tested with water retention data from the Washington soil database and the Unsaturated Soil Hydraulic Database (UNSODA) over nearly the entire range. Both models were also compared with seven existing SWRC models and were evaluated on the basis of the adjusted coefficient of determination (adj R-2), the root mean square error (RMSE) and the Kashyap information criteria (KIC). The testing results showed that the three-segment model performed better than the two-segment model at fitting the SWRC at the dry end. For the three-segment model, the adj R-2 value was greater than 0.90, the RMSE was less than 0.02, and the mean KIC value was -67.0, and these values were superior to those of the other models. In addition, the three-segment model was robust and stable for extrapolation of values in the dry range when data near the dry end were unavailable.
资助项目	National Natural Science Foundation of China[41807166] ; Open Research Fund Program of the State Key Laboratory of Water Resources and Hydropower Engineering Science[2016SWG03] ; Science and Technology Project of the Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences
WOS关键词	HYDRAULIC CONDUCTIVITY ; DRY ; EXPRESSIONS ; EQUATION ; VAPOR
WOS研究方向	Engineering ; Geology ; Water Resources
语种	英语
出版者	ELSEVIER
WOS记录号	WOS:000527390200007
资助机构	National Natural Science Foundation of China ; Open Research Fund Program of the State Key Laboratory of Water Resources and Hydropower Engineering Science ; Science and Technology Project of the Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences
内容类型	期刊论文
源URL	[http://ir.igsnrr.ac.cn/handle/311030/159828]
专题	中国科学院地理科学与资源研究所
通讯作者	Du, Chaoyang
作者单位	1.Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Water Cycle & Related Land Surface Proc, Beijing 100101, Peoples R China 2.Wuhan Univ, State Key Lab Water Resources & Hydropower Engn S, Wuhan 430072, Peoples R China
推荐引用方式 GB/T 7714	Du, Chaoyang. A novel segmental model to describe the complete soil water retention curve from saturation to oven dryness[J]. JOURNAL OF HYDROLOGY,2020,584:10.
APA	Du, Chaoyang.(2020).A novel segmental model to describe the complete soil water retention curve from saturation to oven dryness.JOURNAL OF HYDROLOGY,584,10.
MLA	Du, Chaoyang."A novel segmental model to describe the complete soil water retention curve from saturation to oven dryness".JOURNAL OF HYDROLOGY 584(2020):10.