Global separation of plant transpiration from groundwater and streamflow

  title={Global separation of plant transpiration from groundwater and streamflow},
  author={Jaivime Evaristo and Scott Jasechko and Jeffrey J. McDonnell},
Current land surface models assume that groundwater, streamflow and plant transpiration are all sourced and mediated by the same well mixed water reservoir—the soil. However, recent work in Oregon and Mexico has shown evidence of ecohydrological separation, whereby different subsurface compartmentalized pools of water supply either plant transpiration fluxes or the combined fluxes of groundwater and streamflow. These findings have not yet been widely tested. Here we use hydrogen and oxygen… 
Characterizing the Fluxes and Age Distribution of Soil Water, Plant Water, and Deep Percolation in a Model Tropical Ecosystem
Recent field observations indicate that in many forest ecosystems, plants use water that may be isotopically distinct from soil water that ultimately contributes to streamflow. Such an assertion has
Hydrology: The diversified economics of soil water
  • G. Bowen
  • Environmental Science, Medicine
  • 2015
Building on prior but limited studies, Jaivime Evaristo et al. have assembled a dataset of hydrogen and oxygen isotopes — drawn from widely distributed sites — and show that ecohydrological separation is the rule.
Relative contribution of groundwater to plant transpiration estimated with stable isotopes
The connectivity between groundwater pools and plant water may be quantitatively larger and more widespread than reported by recent global estimations based on isotopic averaged values, and Earth System Models should account for the feedbacks between transpiration and groundwater recharge.
Temporal partitioning of water between plants and hillslope flow in a subtropical climate
Abstract Recent work has suggested that ecohydrological separation may exist between the water sources for recharge and plant water uptake. However, the temporal partitioning of plant transpiration
An evaluation of the ecohydrological separation hypothesis in a semiarid catchment
The ecohydrological separation hypothesis states that transpiration through plants and drainage to streams and groundwater are sourced from separate soil water pools, which possess distinct isotopic
Groundwater and streamflow sources in China's Loess Plateau on catchment scale
Abstract Water sustainability is a major challenge on China's Loess Plateau since drying of soil water and runoff is threatening regional water security. Fundamental to effective water management is
Evapotranspiration dynamics and effects on groundwater recharge and discharge at an arid waste disposal site
Abstract Deserts have been used for waste disposal due to presumed low groundwater recharge. The US Department of Energy is evaluating groundwater flow and contaminant transport at a former uranium
Seasonal origins of soil water used by trees
Abstract. Rain recharges soil water storages and either percolates downward into aquifers and streams or is returned to the atmosphere through evapotranspiration. Although it is commonly assumed that
Using geochemistry to understand water sources and transit times in headwater streams of a temperate rainforest
Abstract Understanding the sources and transit times of water that generates streamflow in headwater streams is important for understanding catchment functioning. This study determines the water
Assessing ecohydrological separation in a northern mixed forest biome using stable isotopes
Abstract. In recent years, much attention has been paid to the issue of ecohydrological separation during water uptake by vegetation. This has been spurred in part by the two water worlds hypothesis,


Tracing the water sources of trees and streams: isotopic analysis in a small pre-alpine catchment
We used a dual stable isotope approach (2H and 18O) and electrical conductivity data in combination with hydrometric measurements to trace water fluxes in the soil, stream and trees in a small
The effect of soil hydrology on the oxygen and hydrogen isotopic compositions of plants’ source water
Abstract Many studies have demonstrated that the isotopic composition of plants’ source water is the main factor affecting the isotopic composition of tree rings. Because of soil hydrological
The two water worlds hypothesis: ecohydrological separation of water between streams and trees?
Recent work in ecohydrology has shown that in some forested watershed systems, streams and trees appear to return different pools of water to the hydrosphere. Thus far, evidence for this has come
Determination of spatiotemporal variability of tree water uptake using stable isotopes (δ18O, δ2H) in an alluvial system supplied by a high‐altitude watershed, Pfyn forest, Switzerland
Sources of water use by 10 alluvial trees in various hydrogeological and ecological situations at the Pfyn forest (Wallis canton, Switzerland) were assessed by analysing 18O and 2H isotopes of
Tree water sources over shallow, saline groundwater in the lower River Murray, south-eastern Australia: implications for groundwater recharge mechanisms
The study has provided a better understanding of the spatial patterns of recharge at a scale relevant to riparian vegetation and is important for the management of floodplain vegetation growing in a saline, semi-arid environment.
Water sources used by riparian trees varies among stream types on the San Pedro River, Arizona.
Variation in the sources of water used by tree species has important ramifications for forest water balances. The fraction of tree transpiration water derived from the unsaturated soil zone and
Stable Isotope Characterization of the Ecohydrological Cycle at a Tropical Treeline Site
ABSTRACT We investigated the seasonal variation in pools of water available to mature trees growing at high elevation in a tropical environment. The study focused on the dominant tree species (Pinus
Water use strategies of two co-occurring tree species in a semi-arid karst environment
The flow of precipitation from the surface through to groundwater in karst systems is a complex process involving storage in the unsaturated zone and diffuse and preferential recharge pathways. The
Growth and water and nitrate uptake patterns of grazed and ungrazed desert shrubs growing over a nitrate contamination plume
Abstract Two native desert shrubs were evaluated for their growth potential and water and nitrogen uptake patterns over a nitrate-contaminated aquifer at a former uranium ore-processing facility in
Terrestrial water fluxes dominated by transpiration
The dominance of transpiration water fluxes in continental evapotranspiration suggests that climate model development should prioritize improvements in simulations of biological fluxes rather than physical (evaporation) fluxes.