Root Foraging Alters Global Patterns of Ecosystem Legacy From Climate Perturbations

Journal of Geophysical Research Biogeosciences, Journal Year: 2022, Volume and Issue: 127(4)

Published: April 1, 2022

Abstract The response of terrestrial ecosystems to climate perturbations typically persist longer than the timescale forcing, a phenomenon broadly referred as legacy . Understanding strength is critical for predicting ecosystem sensitivity extremes and extent that persistent changes in surface‐atmosphere exchange might feedback onto climate. cause has been associated with myriad factors such aboveground biomass, however, few studies have tested how depth distribution fine roots perturbation alter an ecosystem's recovery time. We explore this question using Earth System Model includes dynamic root module where vegetation can forage water nutrients by altering their profiles. global simulations presented here show stress events most deepen In semi‐arid ecosystems, expedites (i.e., less legacy) relative without dynamics because access deeper pools after initial event remains favorable. wetter development profiles slows down more profile reduces thus unfavorable. while inclusion only minimally affect patterns Gross Primary Productivity Evapotranspiration, shift alters recovery. Studies interested sustained land surfaces fluxes disturbances should consider models include capability.

Language: Английский

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Isotopic evaluation of the National Water Model reveals missing agricultural irrigation contributions to streamflow across the western United States

Published: Jan. 17, 2024

Abstract. The National Water Model (NWM) provides critical analyses and projections of streamflow that support water management decisions. However, the NWM performs poorly in lower elevation rivers western United States (US). accuracy depends on fidelity model inputs representation calibration processes sources. To evaluate NWM, we performed a isotope (δ18O δ2H) mass balance using long term mean summer hydrologic fluxes between 2000 2019, gridded precipitation groundwater ratios. We compared NWM-flux-estimated (‘model’) river reach ratios to 4503 in-stream observations 877 reaches across 5 basins US. A simple regression observed estimated explained 57.9 % (δ18O) 67.1 (δ2H) variance, though were 0.5 ‰ 4.8 higher, average, than estimates. unexplained variance suggest does not include all relevant rivers. infer possible missing fluxes, evaluated patterns observation-model differences δ18Odiff (δ18Oobs − δ18Omod) ddiff (δ2Hdiff −8∗δ18Odiff). detected evapoconcentration relative estimates (negative positive δ18Odiff) at elevation, higher stream order, arid sites. catchment actual evaporation ratio, fraction be derived from agricultural irrigation, whether site was reservoir-affected significant predictors linear mixed effects model, with up 15.1 by fixed effects. This finding is supported levels ratios, suggests importance including irrigation return flows rivers, especially Western

Language: Английский

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Dissolving the mystery of subsurface controls on snowmelt–discharge dynamics in karst mountain watersheds using hydrologic timeseries

Hydrological Processes, Journal Year: 2024, Volume and Issue: 38(5)

Published: May 1, 2024

Abstract Streamflow generation in mountain watersheds is strongly influenced by snow accumulation and melt as well groundwater connectivity. In mountainous regions with limestone dolomite geology, bedrock formations can host karst aquifers, which play a significant role snowmelt–discharge dynamics. However, mapping complex features the resulting surface‐groundwater exchanges at large scales remains infeasible. this study, timeseries analysis of continuous discharge specific conductance measurements were combined gridded snowmelt predictions to characterize seasonal streamflow response evaluate dominant watershed controls across 12 monitoring sites karstified 554 km 2 northern Utah, USA. Immense surface water hydrologic variability subcatchments, years seasons was linked geologic on Unlike many watersheds, between subcatchments could not be described typical properties, including elevation or surficial geology. To fill gap, conceptual framework proposed subsurface dynamics terms conduit flow direction, aquifer storage capacity This requires only readily measured climatic data from nested applied study demonstrate its applicability for evaluating climate sensitivity.

Language: Английский

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Isotopic evaluation of the National Water Model reveals missing agricultural irrigation contributions to streamflow across the western United States

Hydrology and earth system sciences, Journal Year: 2024, Volume and Issue: 28(13), P. 2895 - 2918

Published: July 4, 2024

The National Water Model (NWM) provides critical analyses and projections of streamflow that support water management decisions. However, the NWM performs poorly in lower-elevation rivers western United States (US). accuracy depends on fidelity model inputs representation calibration processes sources. To evaluate performance US, we compared observations river isotope ratios (

Language: Английский

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Streamflow timing and magnitude during snow drought depend on snow drought type and regional hydroclimate

Hydrological Sciences Journal, Journal Year: 2024, Volume and Issue: 69(13), P. 1702 - 1716

Published: Sept. 4, 2024

Language: Английский

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