Predicting algal blooms: Are we overlooking groundwater?

The Science of The Total Environment, Год журнала: 2021, Номер 769, С. 144442 - 144442

Опубликована: Янв. 7, 2021

Язык: Английский

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Spatial and Temporal Variability in Concentration‐Discharge Relationships at the Event Scale

Water Resources Research, Год журнала: 2021, Номер 57(10)

Опубликована: Сен. 29, 2021

Abstract The analysis of concentration‐discharge (C‐Q) relationships from low‐frequency observations is commonly used to assess solute sources, mobilization, and reactive transport processes at the catchment scale. High‐frequency concentration measurements are increasingly available offer additional insights into event‐scale export dynamics. However, only few studies have integrated inter‐annual C‐Q relationships. Here, we analyze high‐frequency specific conductance (EC), nitrate (NO 3 ‐N) concentrations spectral absorbance 254 nm (SAC , as a proxy for dissolved organic carbon) over two year period four neighboring catchments in Germany ranging more pristine forested agriculturally managed settings. We apply an method that adds hysteresis term established power law model so intercept, slope can be characterized simultaneously. found inter‐event variability were most pronounced SAC all NO ‐N catchments. event responses smallest closely coupled explainable by antecedent conditions hint common near‐stream source. In contrast, patterns EC agricultural without buffer zones around streams less variable similar relationship indicating homogeneity mobilization time. Event‐scale thus added key functioning whenever contrasted with responses. Analyzing long‐term behavior one coherent framework helps disentangle these scattered patterns.

Язык: Английский

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Climate Controls on River Chemistry

Earth s Future, Год журнала: 2022, Номер 10(6)

Опубликована: Май 16, 2022

Abstract How does climate control river chemistry? Existing literature has examined extensively the response of chemistry to short‐term weather conditions from event seasonal scales. Patterns and drivers long‐term, baseline have remained poorly understood. Here we compile analyze data 506 minimally impacted rivers (412,801 points) in contiguous United States (CAMELS‐Chem) identify patterns chemistry. Despite distinct sources diverse reaction characteristics, a universal pattern emerges for 16 major solutes at continental scale. Their long‐term mean concentrations ( C m ) decrease with discharge Q ), elevated arid climates lower humid climates, indicating overwhelming regulation by compared local Critical Zone characteristics such as lithology topography. To understand pattern, parsimonious watershed reactor model was solved bringing together hydrology (storage–discharge relationship) biogeochemical theories traditionally separate disciplines. The derivation steady state solutions lead power law form relationships. illuminates two competing processes that determine solute concentrations: production subsurface chemical weathering reactions, export (or removal) discharge, water flushing capacity dictated vegetation. In other words, watersheds function primarily reactors produce accumulate transporters climates. With space‐for‐time substitution, these results indicate places where dwindles warming climate, will elevate even without human perturbation, threatening quality aquatic ecosystems. Water deterioration therefore should be considered global calculation future risks.

Язык: Английский

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Hydrologic connectivity and source heterogeneity control concentration–discharge relationships

Hydrological Processes, Год журнала: 2022, Номер 36(9)

Опубликована: Авг. 25, 2022

Abstract Changes in streamwater chemistry have frequently been used to understand the storage and release of water solutes at catchment scale. Streamwater typically varies space time, depending on sources, mobilization mechanisms, pathways solutes. However, less is known about role lateral hydrologic connectivity how it may influence solute export patterns under different wetness conditions. This study analyses long‐term low‐frequency data from four UK catchments using antecedent as proxy for connectivity. We demonstrate that mechanisms can vary wetness, areas become hydrologically connected or disconnected streams. show flow are mostly decoupled dry conditions, leading stronger impacts heterogeneity sources during conditions compared wet Our results vertical distributions need be integrated considered together with temporally variable these stream when assessing chemistry. combined analysis thus enables inferences regarding distribution throughout catchment; also indicates a better understanding relationship between concentrations help identify particularly vulnerable points their potential polluting effects

Язык: Английский

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A deep learning-based novel approach to generate continuous daily stream nitrate concentration for nitrate data-sparse watersheds

The Science of The Total Environment, Год журнала: 2023, Номер 878, С. 162930 - 162930

Опубликована: Март 18, 2023

Язык: Английский

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Subsurface hydrological connectivity controls nitrate export flux in a hilly catchment

Water Research, Год журнала: 2024, Номер 253, С. 121308 - 121308

Опубликована: Фев. 12, 2024

Язык: Английский

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James Buttle Review: The Characteristics of Baseflow Resilience Across Diverse Ecohydrological Terrains

Hydrological Processes, Год журнала: 2025, Номер 39(3)

Опубликована: Март 1, 2025

ABSTRACT The dynamic storage of aquifers is the portion groundwater that can potentially drain to any given point along a stream create baseflow. Baseflow typically occurs year‐round in perennial streams, though characteristics and stability are often most important instream processes during extended dry periods (without precipitation snowmelt) when runoff quickflows minimised. term ‘baseflow resilience’ defined for this review as tendency baseflow streams maintain consistent volume water quality year while under stress from climate variability extremes, with anthropogenic stressors such withdrawals, land use change, degradation. ‘Baseflow has, part, user‐defined meaning spanning supply variables primary interest. Watershed directly impact resilience produce non‐intuitive feedbacks enhance some attributes simultaneously impairing others. For example, permeable corridor geology creates strong stream‐groundwater hydrologic connectivity, yet fast drainage via preferential high‐permeability flowpaths lead streamflow not being sustained periods. Also, shallow sources generally more immediately vulnerable extreme events, warming, salinization, transpiration, drought, compared deeper groundwater. Yet drought influenced by lag years, contaminant legacies may propagate through deep receiving waters decades centuries. Finally, irrigation withdrawals intercept would have drained application leach contaminants soil zone unnaturally raising tables, return flows sustain groundwater‐dependent habitats semiarid areas. This covers concept context summarises common hydrogeological controls on, multiscale of, storage. Further, we present several quantitative metrics assess range using both broadly available boutique data types, subset which demonstrated Delaware River Basin, USA.

Язык: Английский

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Synthesis and adsorption properties investigation of Fe3O4@ZnAl-LDH@MIL-53(Al) for azole fungicides removal from environmental water

Separation and Purification Technology, Год журнала: 2021, Номер 276, С. 119282 - 119282

Опубликована: Июль 15, 2021

Язык: Английский

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Deepening roots can enhance carbonate weathering by amplifying CO<sub>2</sub>-rich recharge

Biogeosciences, Год журнала: 2021, Номер 18(1), С. 55 - 75

Опубликована: Янв. 5, 2021

Abstract. Carbonate weathering is essential in regulating atmospheric CO2 and carbon cycle at the century timescale. Plant roots accelerate by elevating soil via respiration. It however remains poorly understood how much rooting characteristics (e.g., depth density distribution) modify flow paths weathering. We address this knowledge gap using field data from reactive transport numerical experiments Konza Prairie Biological Station (Konza), Kansas (USA), a site where woody encroachment into grasslands surmised to deepen roots. Results indicate that deepening can enhance two ways. First, control thermodynamic limits of carbonate dissolution transports vertical downward deeper carbonate-rich zone. The base-case model reveal concentrations Ca dissolved inorganic (DIC) are regulated pCO2 driven seasonal This relationship be encapsulated equations derived work describing dependence DIC on temperature CO2. explain spring water multiple carbonate-dominated catchments. Second, show rates recharge (or fluxes) zone export reaction products equilibrium. explored potential effects partitioning 40 % infiltrated woodlands compared 5 grasslands. Soil suggest relatively similar distribution over depth, which leads only 1 ∼ 12 difference if was kept same between land covers. In contrast, 17 200 as infiltration increased 3.7 × 10−2 m/a. Weathering these cases more than an order magnitude higher case without all, underscoring role general. Numerical also fronts propagated > 2 times after 300 years rate 0.37 These differences ultimately caused contact CO2-charged with deep subsurface. Within limitation modeling exercises, prompt hypothesis (1) promoting CO2–carbonate subsurface (2) hydrological impacts influential those modulating rates. call for colocated characterizations roots, structure, levels, well their linkage chemistry. measurements will illuminate feedback mechanisms cover changes, chemical weathering, global cycle, climate.

Язык: Английский

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Vertical Connectivity Regulates Water Transit Time and Chemical Weathering at the Hillslope Scale

Water Resources Research, Год журнала: 2021, Номер 57(8)

Опубликована: Июль 13, 2021

Abstract How does hillslope structure (e.g., shape and permeability variation) regulate its hydro‐geochemical functioning (flow paths, solute export, chemical weathering)? Numerical reactive transport experiments particle tracking were used to answer this question. Results underscore the first‐order control of variations (with depth) on vertical connectivity (VC), defined as fraction water flowing into streams from below soil zone. Where decreases sharply VC is low, >95% flows through top 6 m subsurface, barely interacting with rock at depth. High also elongates mean transit times (MTTs) weathering rates. however less an influence under arid climates where long drive equilibrium. The results lead three working hypotheses that can be further tested. H1 : depth MTTs stream more strongly than shapes; shapes instead younger . H2 arising high depths enhances by promoting deeper penetration water‐rock interactions; weakens larger hillslopes longer H3 regulates contrasts between shallow deep waters (C ratio ) export patterns encapsulated in power law slope b concentration‐discharge (CQ) relationships Higher leads similar versus chemistry ∼1) chemostatic CQ Although supporting data already exist, these tested carefully designed, co‐located modeling measurements soil, rock, waters. Broadly, importance subsurface indicate it essential regulating earth surface hydrogeochemical response changing climate human activities.

Язык: Английский

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