From Hydrometeorology to River Water Quality: Can a Deep Learning Model Predict Dissolved Oxygen at the Continental Scale?

Environmental Science & Technology, Journal Year: 2021, Volume and Issue: 55(4), P. 2357 - 2368

Published: Feb. 3, 2021

Dissolved oxygen (DO) reflects river metabolic pulses and is an essential water quality measure. Our capabilities of forecasting DO however remain elusive. Water data, specifically data here, often have large gaps sparse areal temporal coverage. Earth surface hydrometeorology on the other hand, become largely available. Here we ask: can a Long Short-Term Memory (LSTM) model learn about dynamics from intensive (daily) data? We used CAMELS-chem, new set with concentrations 236 minimally disturbed watersheds across U.S. The generally learns theory solubility captures its decreasing trend increasing temperature. It exhibits potential predicting in "chemically ungauged basins", defined as basins without any measurements broadly general. misses some peaks troughs when in-stream biogeochemical processes important. Surprisingly, does not perform better where more are Instead, it performs low variations streamflow DO, high runoff-ratio (>0.45), winter precipitation peaks. Results here suggest that collections at sparsely monitored areas to overcome issue scarcity, outstanding challenge community.

Language: Английский

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Toward catchment hydro‐biogeochemical theories

Wiley Interdisciplinary Reviews Water, Journal Year: 2020, Volume and Issue: 8(1)

Published: Dec. 3, 2020

Abstract Headwater catchments are the fundamental units that connect land to ocean. Hydrological flow and biogeochemical processes intricately coupled, yet their respective sciences have progressed without much integration. Reaction kinetic theories prescribe rate dependence on environmental variables (e.g., temperature water content) advanced substantially, mostly in well‐mixed reactors, columns, warming experiments considering characteristics of hydrological at catchment scale. These shown significant divergence from observations natural systems. On other hand, theories, including transit time theory, substantially not been incorporated into understanding reactions Here we advocate for development integrated hydro‐biogeochemical across gradients climate, vegetation, geology conditions. The lack such presents barriers mechanisms forecasting future Critical Zone under human‐ climate‐induced perturbations. Although integration has started co‐located measurements well way, tremendous challenges remain. In particular, even this era “big data,” still limited by data will need (1) intensify beyond river channels characterize vertical connectivity broadly shallow deep subsurface; (2) expand older dating scales reflected stable isotopes; (3) combine use reactive solutes, nonreactive tracers, (4) augment environments undergoing rapid changes. To develop it is essential engage models all stages model‐informed collection strategies maximize usage; adopt a “simple but simplistic,” or fit‐for‐purpose approach include process‐based models; blend data‐driven framework “theory‐guided science.” Within hypothesis testing, model‐data fusion can advance mechanistically link catchments' internal structures external drivers functioning. It only field hydro‐biogeochemistry, also enable hind‐ fore‐casting serve society large. Broadly, education cultivate thinkers intersections traditional disciplines with hollistic approaches interacting complex earth This article categorized under: Engineering Water > Methods

Language: Английский

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Deep learning for water quality

Nature Water, Journal Year: 2024, Volume and Issue: 2(3), P. 228 - 241

Published: March 12, 2024

Language: Английский

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Groundwater Quality and Health: Making the Invisible Visible

Environmental Science & Technology, Journal Year: 2023, Volume and Issue: 57(13), P. 5125 - 5136

Published: March 6, 2023

Linking groundwater quality to health will make the invisible visible, but there are knowledge gaps understand linkage which requires cross-disciplinary convergent research. The substances in that critical can be classified into five types according sources and characteristics: geogenic substances, biogenic elements, anthropogenic contaminants, emerging pathogens. most intriguing questions related quantitative assessment of human ecological risks exposure via natural or induced artificial discharge: What is list released from discharging groundwater, what pathways receptors' substances? How quantify flux during discharge? procedures we follow assess Answering these fundamental for humans deal with challenges water security quality. This perspective provides recent progresses, gaps, future trends understanding between health.

Language: Английский

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Temperature controls production but hydrology regulates export of dissolved organic carbon at the catchment scale

Hydrology and earth system sciences, Journal Year: 2020, Volume and Issue: 24(2), P. 945 - 966

Published: Feb. 27, 2020

Abstract. Lateral carbon flux through river networks is an important and poorly understood component of the global budget. This work investigates how temperature hydrology control production export dissolved organic (DOC) in Susquehanna Shale Hills Critical Zone Observatory Pennsylvania, USA. Using field measurements daily stream discharge, evapotranspiration, DOC concentration, we calibrated catchment-scale biogeochemical reactive transport model BioRT-Flux-PIHM (Biogeochemical Reactive Transport–Flux–Penn State Integrated Hydrologic Model, BFP), which met satisfactory standard a Nash–Sutcliffe efficiency (NSE) value greater than 0.5. We used to estimate compare rates (Rp; sum local individual grid cells) rate (Re; product concentration discharge at outlet, or load). Results showed that Rp varied by less order magnitude, primarily depending on seasonal temperature. In contrast, Re more 3 orders magnitude was strongly associated with variation hydrological connectivity. summer, high evapotranspiration dried disconnected hillslopes from stream, driving its maximum but minimum. During this period, only exported organic-poor groundwater organic-rich soil water swales bordering stream. The produced accumulated later flushed out during wet cold period (winter spring) when peaked as reconnected uphill reached reproduced observed concentration–discharge (C–Q) relationship characterized unusual flushing–dilution pattern concentrations intermediate indicating three end-members source waters. A sensitivity analysis indicated nonlinearity caused shifts relative contribution different waters under flow conditions. At low reflected chemistry groundwater; dominated swales; concentration. persisted regardless long deeper remained (<18 % streamflow). When increased above 18 %, comparable amounts swale mixed masked swales. case, C–Q patterns switched flushing-only increasing discharge. These results depict conceptual catchment serves producer storage reservoir for hot dry conditions transitions into exporter study also illustrates controls – paths, respectively can create temporal asynchrony scale. Future warming extremes could accentuate asynchrony, occurring periods lateral dominating major storm events.

Language: Английский

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The Shallow and Deep Hypothesis: Subsurface Vertical Chemical Contrasts Shape Nitrate Export Patterns from Different Land Uses

Environmental Science & Technology, Journal Year: 2020, Volume and Issue: 54(19), P. 11915 - 11928

Published: Aug. 19, 2020

Eutrophication has threatened water resources worldwide, yet mechanistic understanding on controls of nutrient export remains elusive. This work tests the shallow and deep hypothesis: subsurface vertical chemical contrasts regulate nitrate patterns under different land use conditions. We synthesized data from 228 watersheds used reactive transport modeling (500 simulations) broad use, climate, geology Data synthesis indicated that human perturbation amplified in (e.g., soil water) versus waters groundwater), inducing primarily flushing (concentrations increase with streamflow) agriculture lands dilution decrease urban watersheds. Results revealed a quantitative relationship between shallow-versus-deep concentration contrasts, underscoring often-overlooked role distribution over depth. challenge commonly held perception legacy stores agricultural induce chemostasis where concentrations vary negligibly streamflow. They suggest will escalate during large hydrological events, which can exacerbate problems as flooding events intensify future climate.

Language: Английский

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Embracing the dynamic nature of soil structure: A paradigm illuminating the role of life in critical zones of the Anthropocene

Earth-Science Reviews, Journal Year: 2021, Volume and Issue: 225, P. 103873 - 103873

Published: Nov. 26, 2021

Language: Английский

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Streams as Mirrors: Reading Subsurface Water Chemistry From Stream Chemistry

Water Resources Research, Journal Year: 2021, Volume and Issue: 58(1)

Published: Oct. 22, 2021

Abstract The shallow and deep hypothesis suggests that stream concentration‐discharge (CQ) relationships are shaped by distinct source waters from different depths. Under this hypothesis, baseflows typically dominated groundwater mostly reflect chemistry, whereas high flows soil water chemistry. Aspects of draw on applications like end member mixing analyses hydrograph separation, yet direct data support for the remains scarce. This work tests using co‐located measurements water, groundwater, streamwater chemistry at two intensively monitored sites, W‐9 catchment Sleepers River (Vermont, United States) Hafren Plynlimon (Wales). At both depth profiles subsurface CQ 10 solutes analyzed broadly consistent with hypothesis. Solutes more abundant (e.g., calcium) exhibit dilution patterns (concentration decreases increasing discharge). Conversely, enriched in soils nitrate) generally flushing increases may hold true catchments share such biogeochemical stratifications subsurface. Soil chemistries were estimated high‐ low‐flow average relative errors ranging 24% to 82%. indicates streams mirror waters: can be used infer scarcely measured especially where there members.

Language: Английский

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How Important is Denitrification in Riparian Zones? Combining End‐Member Mixing and Isotope Modeling to Quantify Nitrate Removal from Riparian Groundwater

Water Resources Research, Journal Year: 2019, Volume and Issue: 56(1)

Published: Dec. 11, 2019

Abstract Riparian zones are important buffer for streams as they hotspots of nitrate transformation and removal in agricultural catchments. However, mixing water from different sources various processes can complicate the quantification turnover riparian zones. In this study, we analyzed concentration isotope data groundwater along a 2‐km stream section central Germany. We developed mathematical model combining end‐member modeling to account river quantify groundwater. This enabled us explicitly determine extent denitrification (as process leading permanent groundwater) transient by additional associated with negligible fractionation (e.g., plant uptake microbial assimilation) perform an extensive uncertainty analysis. Based on nitrogen nitrate, simulations suggest mean up 28% only about 9% denitrification. Nitrate exceeded particularly winter at larger distance river, underlining role organic carbon source. highlights that consumption predominates field site, implying substantial fraction input is not permanently removed but rather retained zone. Overall, our represents useful tool better compare retention temporal spatial scales.

Language: Английский

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Archetypes and Controls of Riverine Nutrient Export Across German Catchments

Water Resources Research, Journal Year: 2021, Volume and Issue: 57(4)

Published: March 14, 2021

Abstract Elevated nutrient inputs challenge the health and functioning of aquatic ecosystems. To improve riverine water quality management, it is necessary to understand underlying biogeochemical physical processes, anthropogenic drivers their interactions at catchment scale. We hypothesize that spatial heterogeneity sources dominantly controls variability in‐stream concentration dynamics among catchments. investigated mean nitrate (NO 3 − ), phosphate (PO 4 3− total organic carbon (TOC) concentrations concentration‐discharge ( C‐Q ) relationships in 787 German catchments a newly assembled data base, covering wide range physiographic settings. linked metrics characteristics using partial least squares regressions random forests. found archetypal patterns with enrichment dominating NO TOC, dilution PO export. Both variance sites increased agricultural land use. argue subsurface denitrification can buffer high nitrogen cause decline depth, resulting chemodynamic, strongly positive patterns. Mean were related point sources, though low predictive power suggests effects unaccounted processes. In contrast, diffuse explained observed TOC levels positively abundance riparian wetlands, while hydrological descriptors important for explaining dynamics. Our study shows strong modulation by natural dynamics, only dominate across Germany.

Language: Английский

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