DOI: 10.5194/hess-21-3839-2017
Scopus记录号: 2-s2.0-85017092003
论文题名: Soil water stable isotopes reveal evaporation dynamics at the soil-plant-atmosphere interface of the critical zone
作者: Sprenger M ; , Tetzlaff D ; , Soulsby C
刊名: Hydrology and Earth System Sciences
ISSN: 10275606
出版年: 2017
卷: 21, 期: 7 起始页码: 3839
结束页码: 3856
语种: 英语
Scopus关键词: Catchments
; Climate change
; Evaporation
; Forestry
; Isotopes
; Land use
; Runoff
; Soil moisture
; Vegetation
; Experimental catchments
; High sampling frequencies
; Hydrological models
; Influence of vegetations
; Isotopic composition
; Potential evaporation
; Seasonal variability
; Temporal and spatial variability
; Soils
; air-soil interaction
; catchment
; climate change
; coniferous tree
; hydrological modeling
; isotopic composition
; isotopic fractionation
; land use change
; plant water relations
; precipitation (chemistry)
; seasonal variation
; soil depth
; soil water
; soil-vegetation interaction
; spatial variation
; stable isotope
; topsoil
; water storage
; water uptake
; Scotland
; United Kingdom
; Calluna
; Erica
; Pinus sylvestris
英文摘要: Understanding the influence of vegetation on water storage and flux in the upper soil is crucial in assessing the consequences of climate and land use change. We sampled the upper 20cm of podzolic soils at 5cm intervals in four sites differing in their vegetation (Scots Pine (Pinus sylvestris) and heather (Calluna sp. and Erica Sp)) and aspect. The sites were located within the Bruntland Burn long-term experimental catchment in the Scottish Highlands, a low energy, wet environment. Sampling took place on 11 occasions between September 2015 and September 2016 to capture seasonal variability in isotope dynamics. The pore waters of soil samples were analyzed for their isotopic composition (δ2H and δ18O) with the direct-equilibration method. Our results show that the soil waters in the top soil are, despite the low potential evaporation rates in such northern latitudes, kinetically fractionated compared to the precipitation input throughout the year. This fractionation signal decreases within the upper 15cm resulting in the top 5cm being isotopically differentiated to the soil at 15-20cm soil depth. There are significant differences in the fractionation signal between soils beneath heather and soils beneath Scots pine, with the latter being more pronounced. But again, this difference diminishes within the upper 15cm of soil. The enrichment in heavy isotopes in the topsoil follows a seasonal hysteresis pattern, indicating a lag time between the fractionation signal in the soil and the increase/decrease of soil evaporation in spring/autumn. Based on the kinetic enrichment of the soil water isotopes, we estimated the soil evaporation losses to be about 5 and 10% of the infiltrating water for soils beneath heather and Scots pine, respectively. The high sampling frequency in time (monthly) and depth (5cm intervals) revealed high temporal and spatial variability of the isotopic composition of soil waters, which can be critical, when using stable isotopes as tracers to assess plant water uptake patterns within the critical zone or applying them to calibrate tracer-aided hydrological models either at the plot to the catchment scale. © Author(s) 2017. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/79099
Appears in Collections: 气候变化事实与影响
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作者单位: Northern Rivers Institute, School of Geosciences, University of Aberdeen, Aberdeen, United Kingdom
Recommended Citation:
Sprenger M,, Tetzlaff D,, Soulsby C. Soil water stable isotopes reveal evaporation dynamics at the soil-plant-atmosphere interface of the critical zone[J]. Hydrology and Earth System Sciences,2017-01-01,21(7)