Integrated monitoring and modeling to disentangle the complex spatio-temporal dynamics of urbanized streams under drought stress

Environmental Monitoring and Assessment, Journal Year: 2024, Volume and Issue: 196(6)

Published: May 20, 2024

We have a poor understanding of how urban drainage and other engineered components interact with more natural hydrological processes in green blue spaces to generate stream flow. This limits the scientific evidence base for predicting mitigating effects future development built environment climate change on water resources their ecosystem services. Here, we synthesize > 20 years environmental monitoring data better understand function 109-km

Language: Английский

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Dissolved phosphorous through dry-wet-dry transitions in a small-dammed river basin: integrated understanding on transport patterns, export controls, and fate

Environmental Science Processes & Impacts, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 1, 2025

The connections between terrestrial DP sources and aquatic sinks were comprehended in a small-dammed watershed through an integrated understanding of transport patterns, export controls, their fate over dry–wet–dry transitions.

Language: Английский

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Hidden Features: How Subsurface and Landscape Heterogeneity Govern Hydrologic Connectivity and Stream Chemistry in a Montane Watershed

Hydrological Processes, Journal Year: 2025, Volume and Issue: 39(3)

Published: March 1, 2025

ABSTRACT Hydrologic connectivity is defined as the connection among stores of water within a watershed and controls flux solutes from subsurface to stream. difficult quantify because it goverened by heterogeniety in storage permeability responds seasonal changes precipitation inputs moisture conditions. How interannual climate variability impacts hydrologic connectivity, thus stream flow generation chemistry, remains unclear. Using rare, four‐year synoptic chemistry dataset, we evaluated shifts source Coal Creek, montane, headwater tributary Upper Colorado River. We leveraged compositional principal component analysis end‐member mixing evaluate how variation conditions chemistry. Overall, three main findings emerged this work. First, geochemically distinct end members were identified that constrained chemistry: reach inflows, quick slow groundwater contributions. Reach inflows impacted historic base precious metal mine inputs. Bedrock fractures facilitated much transport higher‐storage features (e.g., alluvial fans) groundwater. Second, contributions different changed over summer. In early summer, was composed all members, while late predominantly Finally, observed minimal differences proportional composition across four years, indicating spatial heterogeneity landscape geologic had greater influence than fluctuation on These indicate mechanisms controlling solute path activation) may be resilient (i.e., able rebound after perturbations) predicted increases variability. By establishing framework for assessing variable conditions, our study offers method biogeochemical resilience variations hydrometeorological

Language: Английский

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Stochastic volatility model with long memory for water quantity-quality dynamics

Chaos Solitons & Fractals, Journal Year: 2025, Volume and Issue: 195, P. 116167 - 116167

Published: March 14, 2025

Language: Английский

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Cycles in Hydrologic Intensification and De‐Intensification Create Instabilities in Spring Nitrate‐N Export C‐Q Relationships in Northern Temperate Forests

Water Resources Research, Journal Year: 2025, Volume and Issue: 61(3)

Published: March 1, 2025

Abstract Northern temperate forests are experiencing changes from climate and acidification recovery that influence catchment nitrate‐nitrogen (N) flushing behavior. N behavior is characterized by metrics such as: (a) time—the exponential decrease in stream concentration during the peak snowmelt episode; (b) (C) discharge (Q) hysteresis metrics—flushing index (FI) (HI)—representing slope, direction, amplitude of C‐Q loop. We hypothesized climate‐driven hydrologic intensification results longer times, lower FI (less to more diluting), HI proximal distal sources). tested this hypothesis using four decades data two headwater catchments. Hydrologic was estimated ratio potential evapotranspiration precipitation actual precipitation. From 1982 2005, a period decline atmospheric acidic deposition, we observed C Q. This led stable patterns reflected (positive FI) sources HI). However, 2006 2019, de‐intensification coupled with an ongoing deposition associated continued but increase Q, leading unstable shift HI) toward (negative instability less variable large wetland, indicating wetlands buffer against changing conditions.

Language: Английский

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Investigating Spatial and Temporal Nitrogen Dynamics in a Forested Headwater Stream Over the Course of an Annual Drying Event

Journal of Geophysical Research Biogeosciences, Journal Year: 2025, Volume and Issue: 130(4)

Published: March 27, 2025

Abstract Headwater streams make up nearly 80% of the stream network by length and play an important role in shaping physical, chemical, biological functions downstream waters. In Southeastern US, these systems are beginning to experience increases frequency duration drying, but it is unclear how increased drying will impact water quality. To begin address this issue, we examined nitrogen dynamics a forested headwater across annual event. The event was divided into seasonal wet (March–June), dry‐down (June–October), rewet (November–March) periods. We used combination quality sensors at watershed outlet, spatially distributed synoptic sampling net denitrification conditions physicochemical variables watershed, series potential experiments examine variation biogeochemical state At nitrate concentrations were positively correlated with watershed‐scale connectivity during period, while streamflow period. Throughout varied more seasons than space, greater Further, temperature, nitrate, ammonium inversely related streamflow. Finally, measurements confirmed period experienced highest rates. Our results highlight connection between humid systems, providing key information for developing predictive understanding streams.

Language: Английский

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Antecedent Hydrologic Conditions Reflected in Stream Lithium Isotope Ratios During Storms

Geophysical Research Letters, Journal Year: 2024, Volume and Issue: 51(17)

Published: Sept. 8, 2024

Abstract Antecedent hydrological conditions are recorded through the evolution of dissolved lithium isotope signatures (Li) by juxtaposing two storm events in an upland watershed subject to a Mediterranean climate. Discharge and Li negatively correlated both events, but mean ratios associated ranges variation distinct between them. We apply previously developed reactive transport model (RTM) for site these event‐scale flow perturbations, observed shifts stream not reproduced. To reconcile stability subsurface solute weathering profile with our observations dynamic signatures, we couple RTM distribution fluid transit times that evolve based on hydrographs. The approach guides appropriate flux‐weighting from over range path lengths, or equivalently residence times. This flux‐weighted accurately reproduces Li‐discharge patterns distinguished antecedent watershed.

Language: Английский

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Flowpath Partitioning Controls Chemical Weathering Fluxes in the Tropics

Water Resources Research, Journal Year: 2025, Volume and Issue: 61(4)

Published: April 1, 2025

Abstract Tropical watersheds are thought to exert a strong control on the global carbon cycle because elevated temperature and rainfall rates promote chemical weathering of silicate rocks. However, critical factors that tropical weathering, such as role subsurface flowpaths in setting sensitivity climate change, remain obscure. Here, we relate solute dynamics flowpath partitioning using new existing data from Luquillo Critical Zone Observatory (LCZO) forests eastern Puerto Rico. We used measurements deuterium excess streamflow show fraction young water (F yw , less than 1–3 months old) for each catchment increases with increasing discharge. attribute F ‐Q behavior activation shallow efficiently route incident streamflow. Results this 2‐year sampling period comparable results end‐member mixing analysis longer‐term records, suggesting routed via acquires little additional solutes reactions. Our findings apparent between can be unified time‐dependent reactions time‐variable transit time distributions. To estimate response LCZO climatic compare sites experience different mean annual precipitation amounts. Intriguingly, find climatically driven changes reconcile watershed fluxes regolith‐based studies. This suggests is mechanism maintaining constant despite variable supply limited regions where already maximized.

Language: Английский

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Divergence Between Long‐Term and Event‐Scale Nitrate Export Patterns

Geophysical Research Letters, Journal Year: 2024, Volume and Issue: 51(10)

Published: May 23, 2024

Abstract The mechanisms driving catchment nitrogen storage and release operate at multiple spatiotemporal scales. Consequently, analyses grounded in different observational timescales can yield discrepant interpretations of underlying mechanisms. To assess the consistency nitrate export patterns between event‐ inter‐annual scales, we evaluated years high‐frequency observations concentrations (C) discharge (Q) including 3,480 discrete events from 28 dominantly agricultural catchments. We observed consistent often drastic divergence long‐term median event‐specific C‐Q patterns. Most catchments showed enrichment (positive slope), but were, on average, more chemostatic (close‐to‐zero slopes). slope variability was high for small decreased with event magnitude, approaching during largest storms, yielding compelling evidence against source limitation. conclude that temporal scales magnitudes are controlled by processes, therefore embedding complementary information.

Language: Английский

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Solute export patterns across the contiguous USA

Hydrological Processes, Journal Year: 2024, Volume and Issue: 38(6)

Published: June 1, 2024

Abstract Understanding controls on solute export to streams is challenging because heterogeneous catchments can respond uniquely drivers of environmental change. To understand general patterns, we used a large‐scale inductive approach evaluate concentration–discharge (C–Q) metrics across spanning broad range catchment attributes and hydroclimatic drivers. We leveraged paired C–Q data for 11 solutes from CAMELS‐Chem, database built upon an existing dataset relatively undisturbed the contiguous USA. Because relationships with Q thresholds reflect shift in dynamics are poorly characterized diverse catchments, analysed using Bayesian segmented regression quantify relationship. Threshold responses were rare, representing only 12% relationships, 56% which occurred predominantly sourced bedrock. Further, dominated by one or two patterns that reflected vertical solute–source distributions. Specifically, bedrock had diluting 43%–70% soils more enrichment 35%–51% catchments. also linked patterns. The generally weak despite diversity attribute types considered. However, central USA typically drove most divergent behaviour solutes. illustrate how our generated new hypotheses be tested at discrete, representative deductive approaches better processes underlying Finally, given these long‐term minimally disturbed findings as benchmarks change

Language: Английский

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