气候变化领域集成服务门户(CCPortal): Mechanisms of consistently disjunct soil water pools over (pore) space and time

CCPortal

DOI	10.5194/hess-23-2751-2019
	Mechanisms of consistently disjunct soil water pools over (pore) space and time
	Sprenger M.; Llorens P.; Cayuela C.; Gallart F.; Latron J.
发表日期	2019
ISSN	1027-5606
起始页码	2751
结束页码	2762
卷号	23 期号:6
英文摘要	The storage and release of water in soils is critical for sustaining plant transpiration and groundwater recharge. However, how much subsurface mixing of water occurs, and how much of the water is available for plants or otherwise percolates to streams and the groundwater is not yet understood. Based on stable isotope (2H and 18O) data, some studies have found that water infiltrating into soils can bypass older pore water. However, the mechanisms leading to the separation of water routed to the streams and water held tightly in smaller pores are still unclear. Here, we address the current limitations of the understanding of subsurface mixing and their consequences regarding the application of stable isotopes in ecohydrological studies. We present an extensive data set, for which we sampled the isotopic composition of mobile and bulk soil water in parallel with groundwater at a fortnightly temporal resolution and stream water and rainfall at a much higher resolution in a Mediterranean long-term research catchment, in Vallcebre, Spain. The data reveal that the mobile and tightly bound water of a silty loam soil in a Scots pine forest do not mix well; however, they constitute two disjunct subsurface water pools with little exchange, despite intense rainfall events leading to high soil wetness. We show that the isotopic compartmentalization results from the rewetting of small soil pores by isotopically depleted winter/ spring rain. Thus, stable isotopes, and, in turn, water residence times, do not only vary across soil depth, but also across soil pores. Our findings have important implications for stable isotope applications in ecohydrological studies assessing the water uptake by plants or the process realism of hydrological models, as the observed processes are currently rarely implemented in the simulation of water partitioning into evapotranspiration and recharge in the critical zone. © 2019 Copernicus GmbH. All rights reserved.
语种	英语
scopus关键词	Catchments; Digital storage; Evapotranspiration; Forestry; Isotopes; Mixing; Rain; Rivers; Soil moisture; Current limitation; Ground water recharge; Higher resolution; Hydrological models; Isotopic composition; Plant transpiration; Temporal resolution; Water partitioning; Recharging (underground waters); catchment; coniferous forest; ecohydrology; infiltration; Mediterranean soil; percolation; silty loam; soil water; spatiotemporal analysis; stable isotope; subsurface flow; water availability; Barcelona [Catalonia]; Catalonia; Spain; Vallcebre; Pinus sylvestris
来源期刊	Hydrology and Earth System Sciences
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/159659
作者单位	Sprenger, M., Institute of Environmental Assessment and Water Research (IDAEA-CSIC), Calle Jordi Girona, 18-26, Barcelona, 08034, Spain, Department of Forestry and Environmental Resources, North Carolina State University, 2720 Faucette Dr, Raleigh, NC 27606, United States; Llorens, P., Institute of Environmental Assessment and Water Research (IDAEA-CSIC), Calle Jordi Girona, 18-26, Barcelona, 08034, Spain; Cayuela, C., Institute of Environmental Assessment and Water Research (IDAEA-CSIC), Calle Jordi Girona, 18-26, Barcelona, 08034, Spain; Gallart, F., Institute of Environmental Assessment and Water Research (IDAEA-CSIC), Calle Jordi Girona, 18-26, Barcelona, 08034, Spain; Latron, J., Institute of Environmental Assessment and Water Research (IDAEA-CSIC), Calle Jordi Girona, 18-26, Barcelona, 08034, Spain
推荐引用方式 GB/T 7714	Sprenger M.,Llorens P.,Cayuela C.,et al. Mechanisms of consistently disjunct soil water pools over (pore) space and time[J],2019,23(6).
APA	Sprenger M.,Llorens P.,Cayuela C.,Gallart F.,&Latron J..(2019).Mechanisms of consistently disjunct soil water pools over (pore) space and time.Hydrology and Earth System Sciences,23(6).
MLA	Sprenger M.,et al."Mechanisms of consistently disjunct soil water pools over (pore) space and time".Hydrology and Earth System Sciences 23.6(2019).