Articles | Volume 26, issue 22
17 Nov 2022
Research article | 17 Nov 2022
How do inorganic nitrogen processing pathways change quantitatively at daily, seasonal, and multiannual scales in a large agricultural stream?
Jingshui Huang et al.
No articles found.
Carolin Winter, Tam V. Nguyen, Andreas Musolff, Stefanie R. Lutz, Michael Rode, Rohini Kumar, and Jan H. Fleckenstein
Hydrol. Earth Syst. Sci., 27, 303–318,Short summary
The increasing frequency of severe and prolonged droughts threatens our freshwater resources. While we understand drought impacts on water quantity, its effects on water quality remain largely unknown. Here, we studied the impact of the unprecedented 2018–2019 drought in Central Europe on nitrate export in a heterogeneous mesoscale catchment in Germany. We show that severe drought can reduce a catchment's capacity to retain nitrogen, intensifying the internal pollution and export of nitrate.
Xiaoqiang Yang, Doerthe Tetzlaff, Chris Soulsby, and Dietrich Borchardt
Geosci. Model Dev. Discuss.,
Preprint retractedShort summary
We develop the catchment water quality assessment platform HiWaQ v1.0, which is compatible with multiple hydrological model structures. The nitrogen module (HiWaQ-N) and its coupling tests with two contrasting grid-based hydrological models demonstrate the robustness of the platform in estimating catchment N dynamics. With the unique design of the coupling flexibility, HiWaQ can leverage advancements in hydrological modelling and advance integrated catchment water quantity-quality assessments.
Michael Rode, Jörg Tittel, Frido Reinstorf, Michael Schubert, Kay Knöller, Benjamin Gilfedder, Florian Merensky-Pöhlein, and Andreas Musolff
Hydrol. Earth Syst. Sci. Discuss.,
Revised manuscript under review for HESSShort summary
Agricultural catchments often show elevated phosphorus concentrations during summer low flow. In a typical agricultural headwater we found out that geogenic phosphorus in groundwater was the major source of stream water phosphorus during these low-flow conditions and that stream sediments derived from farmland are unlikely to have increased stream phosphorus concentrations during low water. Agricultural land use was not the main cause of P loading in the stream during low-flow conditions.
Rémi Dupas, Andreas Musolff, James W. Jawitz, P. Suresh C. Rao, Christoph G. Jäger, Jan H. Fleckenstein, Michael Rode, and Dietrich Borchardt
Biogeosciences, 14, 4391–4407,Short summary
Carbon and nutrient export regimes were analyzed from archetypal headwater catchments to downstream reaches. In headwater catchments, land use and lithology determine land-to-stream C, N and P transfer processes. The crucial role of riparian zones in C, N and P coupling was investigated. In downstream reaches, point-source contributions and in-stream processes alter C, N and P export regimes.
Julia Vanessa Kunz, Michael D. Annable, Jaehyun Cho, Wolf von Tümpling, Kirk Hatfield, Suresh Rao, Dietrich Borchardt, and Michael Rode
Biogeosciences, 14, 631–649,Short summary
The hyporheic zone, the subsurface region of streams, is a key compartment for in-stream nutrient retention. Knowledge on actual hyporheic processing rates is still limited due to methodological restrictions which are mainly related to the high local and temporal variability of subsurface flow patterns and nutrient transformation processes. We present a new device which allows quantitative assessment of hyporheic nutrient fluxes and demonstrate its advantages in an exemplary field testing.
Related subject area
Subject: Rivers and Lakes | Techniques and Approaches: Modelling approachesExploring tracer information in a small stream to improve parameter identifiability and enhance the process interpretation in transient storage modelsSeasonal forecasting of lake water quality and algal bloom risk using a continuous Gaussian Bayesian networkSpatially referenced Bayesian state-space model of total phosphorus in western Lake ErieFuture water temperature of rivers in Switzerland under climate change investigated with physics-based modelsPhysical controls and a priori estimation of raising land surface elevation across the southwestern Bangladesh delta using tidal river managementEvaluation and interpretation of convolutional long short-term memory networks for regional hydrological modellingSynthesizing the impacts of baseflow contribution on concentration–discharge (C–Q) relationships across Australia using a Bayesian hierarchical modelCalibrating 1D hydrodynamic river models in the absence of cross-section geometry using satellite observations of water surface elevation and river widthA global algorithm for identifying changing streamflow regimes: application to Canadian natural streams (1966–2010)Streamflow drought: implication of drought definitions and its application for drought forecastingQuantifying floodwater impacts on a lake water budget via volume-dependent transient stable isotope mass balanceRiver runoff in Switzerland in a changing climate – changes in moderate extremes and their seasonalityRiver runoff in Switzerland in a changing climate – runoff regime changes and their time of emergenceMachine-learning methods for stream water temperature predictionBathymetry and latitude modify lake warming under iceLake thermal structure drives interannual variability in summer anoxia dynamics in a eutrophic lake over 37 yearsReservoir evaporation in a Mediterranean climate: comparing direct methods in Alqueva Reservoir, PortugalDiverging hydrological drought traits over Europe with global warmingAnthropogenic influence on the Rhine water temperaturesA new form of the Saint-Venant equations for variable topographySimulations of future changes in thermal structure of Lake Erken: proof of concept for ISIMIP2b lake sector local simulation strategyAssessment of the geomorphic effectiveness of controlled floods in a braided river using a reduced-complexity numerical modelWorldwide lake level trends and responses to background climate variationModeling inorganic carbon dynamics in the Seine River continuum in FranceA data-based predictive model for spatiotemporal variability in stream water qualityFlooding in the Mekong Delta: the impact of dyke systems on downstream hydrodynamicsReconstruction of the 1941 GLOF process chain at Lake Palcacocha (Cordillera Blanca, Peru)Historical modelling of changes in Lake Erken thermal conditionsImproving lake mixing process simulations in the Community Land Model by using K profile parameterizationUpgraded global mapping information for earth system modelling: an application to surface water depth at the ECMWFSediment transport modelling in riverine environments: on the importance of grain-size distribution, sediment density, and suspended sediment concentrations at the upstream boundaryReplication of ecologically relevant hydrological indicators following a modified covariance approach to hydrological model parameterizationLidar-based approaches for estimating solar insolation in heavily forested streamsNumerical study on the response of the largest lake in China to climate changeUnraveling the hydrological budget of isolated and seasonally contrasted subtropical lakesFuture projections of temperature and mixing regime of European temperate lakesConservative finite-volume forms of the Saint-Venant equations for hydrology and urban drainageModelling Lake Titicaca's daily and monthly evaporationPrincipal components of thermal regimes in mountain river networksModelling the water balance of Lake Victoria (East Africa) – Part 1: Observational analysisModelling the water balance of Lake Victoria (East Africa) – Part 2: Future projectionsBreeze effects at a large artificial lake: summer case studyImpacts of changing hydrology on permanent gully growth: experimental resultsExtrapolating regional probability of drying of headwater streams using discrete observations and gauging networksPassive acoustic measurement of bedload grain size distribution using self-generated noiseCan riparian vegetation shade mitigate the expected rise in stream temperatures due to climate change during heat waves in a human-impacted pre-alpine river?Tributaries affect the thermal response of lakes to climate changeParameter sensitivity analysis of a 1-D cold region lake model for land-surface schemesResponse of water temperatures and stratification to changing climate in three lakes with different morphometryImpacts of changes in groundwater recharge on the isotopic composition and geochemistry of seasonally ice-covered lakes: insights for sustainable management
Enrico Bonanno, Günter Blöschl, and Julian Klaus
Hydrol. Earth Syst. Sci., 26, 6003–6028,Short summary
There is an unclear understanding of which processes regulate the transport of water, solutes, and pollutants in streams. This is crucial since these processes control water quality in river networks. Compared to other approaches, we obtained clearer insights into the processes controlling solute transport in the investigated reach. This work highlights the risks of using uncertain results for interpreting the processes controlling water movement in streams.
Leah A. Jackson-Blake, François Clayer, Sigrid Haande, James E. Sample, and S. Jannicke Moe
Hydrol. Earth Syst. Sci., 26, 3103–3124,Short summary
We develop a Gaussian Bayesian network (GBN) for seasonal forecasting of lake water quality and algal bloom risk in a nutrient-impacted lake in southern Norway. Bayesian networks are powerful tools for environmental modelling but are almost exclusively discrete. We demonstrate that a continuous GBN is a promising alternative approach. Predictive performance of the GBN was similar or improved compared to a discrete network, and it was substantially less time-consuming and subjective to develop.
Timothy J. Maguire, Craig A. Stow, and Casey M. Godwin
Hydrol. Earth Syst. Sci., 26, 1993–2017,Short summary
Water within large water bodies is constantly moving. Consequently, water movement masks causal relationships that exist between rivers and lakes. Incorporating water movement into models of nutrient concentration allows us to predict concentrations at unobserved locations and at observed locations on days not sampled. Our modeling approach does this while accommodating nutrient concentration data from multiple sources and provides a way to experimentally define the impact of rivers on lakes.
Adrien Michel, Bettina Schaefli, Nander Wever, Harry Zekollari, Michael Lehning, and Hendrik Huwald
Hydrol. Earth Syst. Sci., 26, 1063–1087,Short summary
This study presents an extensive study of climate change impacts on river temperature in Switzerland. Results show that, even for low-emission scenarios, water temperature increase will lead to adverse effects for both ecosystems and socio-economic sectors throughout the 21st century. For high-emission scenarios, the effect will worsen. This study also shows that water seasonal warming will be different between the Alpine regions and the lowlands. Finally, efficiency of models is assessed.
Md Feroz Islam, Paul P. Schot, Stefan C. Dekker, Jasper Griffioen, and Hans Middelkoop
Hydrol. Earth Syst. Sci., 26, 903–921,Short summary
The potential of sedimentation in the lowest parts of polders (beels) through controlled flooding with dike breach (tidal river management – TRM) to counterbalance relative sea level rise (RSLR) in 234 beels of SW Bangladesh is determined in this study, using 2D models and multiple regression. Lower beels located closer to the sea have the highest potential. Operating TRM only during the monsoon season is sufficient to raise the land surface of most beels by more than 3 times the yearly RSLR.
Sam Anderson and Valentina Radić
Hydrol. Earth Syst. Sci., 26, 795–825,Short summary
We develop and interpret a spatiotemporal deep learning model for regional streamflow prediction at more than 200 stream gauge stations in western Canada. We find the novel modelling style to work very well for daily streamflow prediction. Importantly, we interpret model learning to show that it has learned to focus on physically interpretable and physically relevant information, which is a highly desirable quality of machine-learning-based hydrological models.
Danlu Guo, Camille Minaudo, Anna Lintern, Ulrike Bende-Michl, Shuci Liu, Kefeng Zhang, and Clément Duvert
Hydrol. Earth Syst. Sci., 26, 1–16,Short summary
We investigate the impact of baseflow contribution on concentration–flow (C–Q) relationships across the Australian continent. We developed a novel Bayesian hierarchical model for six water quality variables across 157 catchments that span five climate zones. For sediments and nutrients, the C–Q slope is generally steeper for catchments with a higher median and a greater variability of baseflow contribution, highlighting the key role of variable flow pathways in particulate and solute export.
Liguang Jiang, Silja Westphal Christensen, and Peter Bauer-Gottwein
Hydrol. Earth Syst. Sci., 25, 6359–6379,Short summary
River roughness and geometry are essential to hydraulic river models. However, measurements of these quantities are not available in most rivers globally. Nevertheless, simultaneous calibration of channel geometric parameters and roughness is difficult as they compensate for each other. This study introduces an alternative approach of parameterization and calibration that reduces parameter correlations by combining cross-section geometry and roughness into a conveyance parameter.
Masoud Zaerpour, Shadi Hatami, Javad Sadri, and Ali Nazemi
Hydrol. Earth Syst. Sci., 25, 5193–5217,Short summary
Streamflow regimes are changing globally particularly in cold regions. We develop a novel algorithm for detecting shifting streamflow regimes using changes in first and second moments of ensemble streamflow features. This algorithm is generic and can be used globally. To showcase its application, we assess alterations in Canadian natural streams from 1966 to 2010 to provide the first temporally consistent, pan-Canadian assessment of change in natural streamflow regimes, coast to coast to coast.
Samuel J. Sutanto and Henny A. J. Van Lanen
Hydrol. Earth Syst. Sci., 25, 3991–4023,Short summary
This paper provides a comprehensive overview of the differences within streamflow droughts derived using different identification approaches, namely the variable threshold, fixed threshold, and the Standardized Streamflow Index, including an analysis of both historical drought and implications for forecasting. Our results clearly show that streamflow droughts derived from different approaches deviate from each other in terms of drought occurrence, timing, duration, and deficit volume.
Janie Masse-Dufresne, Florent Barbecot, Paul Baudron, and John Gibson
Hydrol. Earth Syst. Sci., 25, 3731–3757,Short summary
A volume-dependent transient isotopic mass balance model was developed for an artificial lake in Canada, in a context where direct measurements of surface water fluxes are difficult. It revealed that floodwater inputs affected the dynamics of the lake in spring but also significantly influenced the long-term water balance due to temporary subsurface storage of floodwater. Such models are paramount for understanding the vulnerability of lakes to changes in groundwater quantity and quality.
Regula Muelchi, Ole Rössler, Jan Schwanbeck, Rolf Weingartner, and Olivia Martius
Hydrol. Earth Syst. Sci., 25, 3577–3594,Short summary
This study analyses changes in magnitude, frequency, and seasonality of moderate low and high flows for 93 catchments in Switzerland. In lower-lying catchments (below 1500 m a.s.l.), moderate low-flow magnitude (frequency) will decrease (increase). In Alpine catchments (above 1500 m a.s.l.), moderate low-flow magnitude (frequency) will increase (decrease). Moderate high flows tend to occur more frequent, and their magnitude increases in most catchments except some Alpine catchments.
Regula Muelchi, Ole Rössler, Jan Schwanbeck, Rolf Weingartner, and Olivia Martius
Hydrol. Earth Syst. Sci., 25, 3071–3086,Short summary
Runoff regimes in Switzerland will change significantly under climate change. Projected changes are strongly elevation dependent with earlier time of emergence and stronger changes in high-elevation catchments where snowmelt and glacier melt play an important role. The magnitude of change and the climate model agreement on the sign increase with increasing global mean temperatures and stronger emission scenarios. This amplification highlights the importance of climate change mitigation.
Moritz Feigl, Katharina Lebiedzinski, Mathew Herrnegger, and Karsten Schulz
Hydrol. Earth Syst. Sci., 25, 2951–2977,Short summary
In this study we developed machine learning approaches for daily river water temperature prediction, using different data preprocessing methods, six model types, a range of different data inputs and 10 study catchments. By comparing to current state-of-the-art models, we could show a significant improvement of prediction performance of the tested approaches. Furthermore, we could gain insight into the relationships between model types, input data and predicted stream water temperature.
Cintia L. Ramón, Hugo N. Ulloa, Tomy Doda, Kraig B. Winters, and Damien Bouffard
Hydrol. Earth Syst. Sci., 25, 1813–1825,Short summary
When solar radiation penetrates the frozen surface of lakes, shallower zones underneath warm faster than deep interior waters. This numerical study shows that the transport of excess heat to the lake interior depends on the lake circulation, affected by Earth's rotation, and controls the lake warming rates and the spatial distribution of the heat flux across the ice–water interface. This work contributes to the understanding of the circulation and thermal structure patterns of ice-covered lakes.
Robert Ladwig, Paul C. Hanson, Hilary A. Dugan, Cayelan C. Carey, Yu Zhang, Lele Shu, Christopher J. Duffy, and Kelly M. Cobourn
Hydrol. Earth Syst. Sci., 25, 1009–1032,Short summary
Using a modeling framework applied to 37 years of dissolved oxygen time series data from Lake Mendota, we identified the timing and intensity of thermal energy stored in the lake water column, the lake's resilience to mixing, and surface primary production as the most important drivers of interannual dynamics of low oxygen concentrations at the lake bottom. Due to climate change, we expect an increase in the spatial and temporal extent of low oxygen concentrations in Lake Mendota.
Carlos Miranda Rodrigues, Madalena Moreira, Rita Cabral Guimarães, and Miguel Potes
Hydrol. Earth Syst. Sci., 24, 5973–5984,Short summary
In Mediterranean environments, evaporation is a key component of reservoir water budgets. Prediction of surface evaporation becomes crucial for adequate reservoir water management. This study provides an applicable method for calculating evaporation based on pan measurements applied at Alqueva Reservoir (southern Portugal), one of the largest artificial lakes in Europe. Moreover, the methodology presented here could be applied to other Mediterranean reservoirs.
Carmelo Cammalleri, Gustavo Naumann, Lorenzo Mentaschi, Bernard Bisselink, Emiliano Gelati, Ad De Roo, and Luc Feyen
Hydrol. Earth Syst. Sci., 24, 5919–5935,Short summary
Climate change is anticipated to alter the demand and supply of water at the earth's surface. This study shows how hydrological droughts will change across Europe with increasing global warming levels, showing that at 3 K global warming an additional 11 million people and 4.5 ×106 ha of agricultural land will be exposed to droughts every year, on average. These effects are mostly located in the Mediterranean and Atlantic regions of Europe.
Alex Zavarsky and Lars Duester
Hydrol. Earth Syst. Sci., 24, 5027–5041,Short summary
River water temperature is an important parameter for water quality and an important variable for physical, chemical and biological processes. River water is also used as a cooling agent by power plants and production facilities. We study long-term trends in river water temperature and correlate them to meteorological influences and power production or economic indices.
Cheng-Wei Yu, Ben R. Hodges, and Frank Liu
Hydrol. Earth Syst. Sci., 24, 4001–4024,Short summary
This study investigates the effects of bottom slope discontinuity on the stability of numerical solutions for the Saint-Venant equations. A new reference slope concept is proposed to ensure smooth source terms and eliminate potential numerical oscillations. It is shown that a simple algebraic transformation of channel geometry provides a smooth reference slope while preserving the correct cross-sectional flow area and the piezometric pressure gradient that drives the flow.
Ana I. Ayala, Simone Moras, and Donald C. Pierson
Hydrol. Earth Syst. Sci., 24, 3311–3330,Short summary
The impacts of different levels of global warming on the thermal structure of Lake Erken are assessed. We used the General Ocean Turbulence Model (GOTM) to simulate water temperature driven by meteorological scenarios supplied by the Inter-Sectoral Impact Model Intercomparison Project (ISIMIP) and tested its ability at different frequencies. Then, daily ISIMIP meteorological scenarios were disaggregated and assessed for the effects of climate change on lake thermal structure.
Luca Ziliani, Nicola Surian, Gianluca Botter, and Luca Mao
Hydrol. Earth Syst. Sci., 24, 3229–3250,Short summary
Although geomorphic recovery is a key issue in many rivers worldwide, controlled floods have been rarely designed using geomorphological criteria. An integrated approach is used to assess the effects of different controlled-flood scenarios in a strongly regulated river. None of the controlled-flood strategies provide significant morphological benefits. Nevertheless, this study represents a significant contribution for the management and restoration of highly disturbed rivers.
Benjamin M. Kraemer, Anton Seimon, Rita Adrian, and Peter B. McIntyre
Hydrol. Earth Syst. Sci., 24, 2593–2608,Short summary
Lake levels go up and down due to natural variability in the climate. But the effects of natural variability on lake levels can sometimes be confused for the influence of humans. Here we used long-term data from 200 globally distributed lakes and an advanced statistical approach to show that the effects of natural variability on lake levels can be disentangled from other effects leading to better estimates of long-term changes that may be partially caused by humans.
Audrey Marescaux, Vincent Thieu, Nathalie Gypens, Marie Silvestre, and Josette Garnier
Hydrol. Earth Syst. Sci., 24, 2379–2398,Short summary
Rivers have been recognized as an active part of the carbon cycle where transformations are associated with CO2 outgassing. To understand it, we propose a modeling approach with the biogeochemical model, pyNuts-Riverstrahler. We implemented it on the human-impacted Seine River. Sources of carbon to the river were characterized by field measurements in groundwater and in wastewater. Outgassing was the most important in streams, and peaks were simulated downstream of wastewater treatment effluent.
Danlu Guo, Anna Lintern, J. Angus Webb, Dongryeol Ryu, Ulrike Bende-Michl, Shuci Liu, and Andrew William Western
Hydrol. Earth Syst. Sci., 24, 827–847,Short summary
This study developed predictive models to represent the spatial and temporal variation of stream water quality across Victoria, Australia. The model structures were informed by a data-driven approach, which identified the key controls of water quality variations from long-term records. These models are helpful to identify likely future changes in water quality and, in turn, provide critical information for developing management strategies to improve stream water quality.
Vo Quoc Thanh, Dano Roelvink, Mick van der Wegen, Johan Reyns, Herman Kernkamp, Giap Van Vinh, and Vo Thi Phuong Linh
Hydrol. Earth Syst. Sci., 24, 189–212,Short summary
The Vietnamese Mekong Delta (VMD) is a rice bowl of not only Vietnam, but also the world; agriculture is the main source of livelihood in the delta. The VMD is facing threats related to water management and hydraulic structures. Dykes are built to protect agricultural crops in the floodplains and may influence water regimes downstream in the VMD. If the VMD floodplains are completely protected by dykes, yearly mean water levels could increase by 3 cm (at Can Tho) and 1.5 cm (at My Thuan).
Martin Mergili, Shiva P. Pudasaini, Adam Emmer, Jan-Thomas Fischer, Alejo Cochachin, and Holger Frey
Hydrol. Earth Syst. Sci., 24, 93–114,Short summary
In 1941, the glacial lagoon Lake Palcacocha in the Cordillera Blanca (Peru) drained suddenly. The resulting outburst flood/debris flow consumed another lake and had a disastrous impact on the town of Huaraz 23 km downstream. We reconstuct this event through a numerical model to learn about the possibility of prediction of similar processes in the future. Remaining challenges consist of the complex process interactions and the lack of experience due to the rare occurrence of such process chains.
Simone Moras, Ana I. Ayala, and Don C. Pierson
Hydrol. Earth Syst. Sci., 23, 5001–5016,Short summary
We used a hydrodynamic model to reconstruct daily historical water temperature of Lake Erken (Sweden) between 1961 and 2017 to demonstrate the ongoing effect of climate change on lake thermal conditions. The results show that the lake has warmed most rapidly in the last 30 years and that it is now subject to a longer and more stable stratification. The methods used here to reconstruct historical water temperature records can be easily extended to other lakes.
Qunhui Zhang, Jiming Jin, Xiaochun Wang, Phaedra Budy, Nick Barrett, and Sarah E. Null
Hydrol. Earth Syst. Sci., 23, 4969–4982,Short summary
We improved lake mixing process simulations by applying a vertical mixing scheme, K profile parameterization (KPP), in the Community Land Model (CLM) version 4.5, developed by the National Center for Atmospheric Research. The current vertical mixing scheme in CLM requires an arbitrarily enlarged eddy diffusivity to enhance water mixing. The coupled CLM-KPP considers a boundary layer for eddy development. The improved lake model provides an important tool for lake hydrology and ecosystem studies.
Margarita Choulga, Ekaterina Kourzeneva, Gianpaolo Balsamo, Souhail Boussetta, and Nils Wedi
Hydrol. Earth Syst. Sci., 23, 4051–4076,Short summary
Lakes influence weather and climate of regions, especially if several of them are located close by. Just by using upgraded lake depths, based on new or more recent measurements and geological methods of depth estimation, errors of lake surface water forecasts produced by the European Centre for Medium-Range Weather Forecasts became 12–20 % lower compared with observations for 27 lakes collected by the Finnish Environment Institute. For ice-off date forecasts errors changed insignificantly.
Jérémy Lepesqueur, Renaud Hostache, Núria Martínez-Carreras, Emmanuelle Montargès-Pelletier, and Christophe Hissler
Hydrol. Earth Syst. Sci., 23, 3901–3915,Short summary
This article evaluates the influence of sediment representation in a sediment transport model. A short-term simulation is used to assess how far changing the sediment characteristics in the modelling experiment changes riverbed evolution and sediment redistribution during a small flood event. The study shows in particular that representing sediment with extended grain-size and grain-density distributions allows for improving model accuracy and performances.
Annie Visser-Quinn, Lindsay Beevers, and Sandhya Patidar
Hydrol. Earth Syst. Sci., 23, 3279–3303,Short summary
The ecological impact of changes in river flow may be explored through the simulation of ecologically relevant flow indicators. Traditional approaches to model parameterization are not well-suited for this. To this end, this paper considers the ability of a
modified covariance approach, applied to five hydrologically diverse catchments. An overall improvement in consistency is observed, whilst timing and rate of change represent the best and worst replicated indicators respectively.
Jeffrey J. Richardson, Christian E. Torgersen, and L. Monika Moskal
Hydrol. Earth Syst. Sci., 23, 2813–2822,Short summary
High stream temperatures can be detrimental to the survival of aquatic species such as endangered salmon. Stream temperatures can be reduced by shade provided by trees in riparian areas. Two lidar-based methods were effective at assessing stream shading. These methods can be used in place of expensive field measurements.
Dongsheng Su, Xiuqing Hu, Lijuan Wen, Shihua Lyu, Xiaoqing Gao, Lin Zhao, Zhaoguo Li, Juan Du, and Georgiy Kirillin
Hydrol. Earth Syst. Sci., 23, 2093–2109,Short summary
In this study, freshwater lake model simulation results, verified by satellite and buoy observation data, were used to quantify recent climate change effects on the thermal regime of the largest lake in China. Results indicate that the FLake model can reproduce the lake thermal pattern nicely. The lake surface is warming, while the lake bottom has no significant trend. Climate change also caused an earlier ice-off and later ice-on, leading to an obvious change in the energy balance of the lake.
Chloé Poulin, Bruno Hamelin, Christine Vallet-Coulomb, Guinbe Amngar, Bichara Loukman, Jean-François Cretaux, Jean-Claude Doumnang, Abdallah Mahamat Nour, Guillemette Menot, Florence Sylvestre, and Pierre Deschamps
Hydrol. Earth Syst. Sci., 23, 1705–1724,Short summary
This study investigates the water budget of two intertropical lake systems in the absence of long-term hydrological monitoring. By coupling dry season isotopic data with satellite imagery, we were able to provide quantitative constrains on the hydrological balance and show that these two lake systems can be considered miniature analogs of Lake Chad, making them important targets in the future setup of any large-scale program on the hydro-climatic evolution in the Sahel region.
Tom Shatwell, Wim Thiery, and Georgiy Kirillin
Hydrol. Earth Syst. Sci., 23, 1533–1551,Short summary
We used models to project future temperature and mixing in temperate lakes. Lakes will probably warm faster in winter than in summer, making ice less frequent and altering mixing. We found that the layers that form seasonally in lakes (ice, stratification) and water clarity affect how lakes accumulate heat. Seasonal changes in climate were thus important. This helps us better understand how different lake types respond to warming and which physical changes to expect in the future.
Ben R. Hodges
Hydrol. Earth Syst. Sci., 23, 1281–1304,Short summary
A new derivation of the equations for one-dimensional open-channel flow in rivers and storm drainage systems has been developed. The new approach solves some long-standing problems for obtaining well-behaved solutions with conservation forms of the equations. This research was motivated by the need for highly accurate models of large-scale river networks and the storm drainage systems in megacities. Such models are difficult to create with existing equation forms.
Ramiro Pillco Zolá, Lars Bengtsson, Ronny Berndtsson, Belen Martí-Cardona, Frederic Satgé, Franck Timouk, Marie-Paule Bonnet, Luis Mollericon, Cesar Gamarra, and José Pasapera
Hydrol. Earth Syst. Sci., 23, 657–668,Short summary
The evaporation was computed at a daily time step and compared with the estimated evaporation using mean monthly meteorological observations. We found that the most reliable method of determining the annual lake evaporation is using the heat balance approach.
Daniel J. Isaak, Charles H. Luce, Gwynne L. Chandler, Dona L. Horan, and Sherry P. Wollrab
Hydrol. Earth Syst. Sci., 22, 6225–6240,Short summary
Description of thermal regimes in flowing waters is key to understanding physical processes and improving bioassessments, but has been limited by sparse data sets. Using a large annual temperature data set from a mountainous area of the western U.S., we explored thermal regimes using principle component analysis. A small number of summary metrics adequately represented most of the variation in this data set given strong temporal coherence among sites.
Inne Vanderkelen, Nicole P. M. van Lipzig, and Wim Thiery
Hydrol. Earth Syst. Sci., 22, 5509–5525,Short summary
Lake Victoria is the largest lake in Africa and one of the two major sources of the Nile river. The water level of Lake Victoria is determined by its water balance, consisting of lake precipitation and evaporation, inflow from rivers and lake outflow, controlled by two hydropower dams. Here, we present a water balance model for Lake Victoria, which closely represents the observed lake levels. The model results highlight the sensitivity of the lake level to human operations at the dam.
Inne Vanderkelen, Nicole P. M. van Lipzig, and Wim Thiery
Hydrol. Earth Syst. Sci., 22, 5527–5549,Short summary
Lake Victoria is the second largest freshwater lake in the world and one of the major sources of the Nile River, which is controlled by two hydropower dams. In this paper we estimate the potential consequences of climate change for future water level fluctuations of Lake Victoria. Our results reveal that the operating strategies at the dam are the main controlling factors of future lake levels and that regional climate simulations used in the projections encompass large uncertainties.
Maksim Iakunin, Rui Salgado, and Miguel Potes
Hydrol. Earth Syst. Sci., 22, 5191–5210,Short summary
Lakes and reservoirs can affect local weather regimes but usually it is difficult to trace and assess it. In this work we used the Meso-NH atmospheric model to study the impact of the Alqueva reservoir, one of the largest artificial lakes in western Europe, located in the southeast of Portugal, on meteorological parameters and the formation of a lake breeze system. The magnitude of this impact as well as the intensity of the breeze are shown in the paper.
Stephanie S. Day, Karen B. Gran, and Chris Paola
Hydrol. Earth Syst. Sci., 22, 3261–3273,Short summary
Permanent gullies are deep steep-sided channels that erode as water falls over the upstream end. Erosion of these features is a concern where people and climate change have altered how water moves over the land. This paper analyzes a set of experiments that were used to determine how changing gully flows impact erosion. We found that while increasing the volume of water will increase erosion, changing the flow rate into gullies will not impact the total erosion, but will alter gully shape.
Aurélien Beaufort, Nicolas Lamouroux, Hervé Pella, Thibault Datry, and Eric Sauquet
Hydrol. Earth Syst. Sci., 22, 3033–3051,Short summary
Streams which may stop flowing are poorly gauged. To improve their characterisation, we use an extended network providing monthly visual observations stating whether streams are flowing or not across France. These observations are combined with discharge and groundwater level in models to predict daily regional probability of drying. This approach allows identification of the most impacted regions by flow intermittence and estimation of the probability of drying dynamics over the last 27 years.
Teodor Petrut, Thomas Geay, Cédric Gervaise, Philippe Belleudy, and Sebastien Zanker
Hydrol. Earth Syst. Sci., 22, 767–787,Short summary
Our interest is focused on developing the hydrophone technique to estimate the size of particles transported in rivers. The analytic spectral solution of the impact between rigid particles is used to model the power spectrum of a sediment mixture, or the sediment-generated noise. Estimations of grain size distributions in the Isère River using real measured spectra are successfully validated by the physical sampling techniques. Moreover, the grain size sorting process is revealed by acoustics.
Heidelinde Trimmel, Philipp Weihs, David Leidinger, Herbert Formayer, Gerda Kalny, and Andreas Melcher
Hydrol. Earth Syst. Sci., 22, 437–461,Short summary
In eastern Austria, where air temperature rise is double that recorded globally, stream temperatures of a human-impacted river were simulated during heat waves, as calculated by regional climate models until 2100. An increase of up to 3 °C was predicted – thus exceeding thresholds of resident cold-adapted species. Vegetation management scenarios showed that adding vegetation can reduce both absolute temperatures and its rate of increase but is not able to fully mitigate the expected rise.
Love Råman Vinnå, Alfred Wüest, Massimiliano Zappa, Gabriel Fink, and Damien Bouffard
Hydrol. Earth Syst. Sci., 22, 31–51,Short summary
Responses of inland waters to climate change vary on global and regional scales. Shifts in river discharge regimes act as positive and negative feedbacks in influencing water temperature. The extent of this effect on warming is controlled by the change in river discharge and lake hydraulic residence time. A shift of deep penetrating river intrusions from summer towards winter can potentially counteract the otherwise negative climate effects on deep-water oxygen content.
José-Luis Guerrero, Patricia Pernica, Howard Wheater, Murray Mackay, and Chris Spence
Hydrol. Earth Syst. Sci., 21, 6345–6362,Short summary
Lakes are sentinels of climate change, and an adequate characterization of their feedbacks to the atmosphere could improve climate modeling. These feedbacks, as heat fluxes, can be simulated but are seldom measured, casting doubt on modeling results. Measurements from a small lake in Canada established that the model parameter modulating how much light penetrates the lake dominates model response. This parameter is measurable: improved monitoring could lead to more robust modeling.
Madeline R. Magee and Chin H. Wu
Hydrol. Earth Syst. Sci., 21, 6253–6274,Short summary
Water temperatures and stratification in three morphometrically different lakes over the century are examined. Simulations showed that epilimnetic temperatures increased, hypolimnetic temperatures decreased, the length of the stratified season increased due to earlier stratification onset and later fall overturn, and stability increased. Results showed that wind speed has a large effect on temperature and stratification variables, sometimes greater than changes in air temperature.
Marie Arnoux, Florent Barbecot, Elisabeth Gibert-Brunet, John Gibson, and Aurélie Noret
Hydrol. Earth Syst. Sci., 21, 5875–5889,Short summary
Future climate and recharge change scenarios are tested on lake hydrological balances to simulate changes in lake isotopic signature and water quality. Results highlight that lake water evolution depends mainly on the location and the intensity of recharge changes. Lake water isotopic composition appears to be particularly sensitive to future changes in recharge for lakes with between 50 % and 80 % of groundwater in their total inflows.
Burgin, A. J. and Hamilton, S. K.: Have we overemphasized the role of denitrification in aquatic ecosystems? A review of nitrate removal pathways, Front. Ecol. Environ., 5, 89–96, https://doi.org/10.1890/1540-9295(2007)5[89:HWOTRO]2.0.CO;2, 2007.
Chapra, S. C.: Surface water-quality modeling, Waveland Press, Long Grove, IL, US, 2008.
Cooper, A. B. and Cooke, J. G.: Nitrate loss and transformation in 2 vegetated headwater streams, New Zeal. J. Mar. Fresh., 18, 441–450, https://doi.org/10.1080/00288330.1984.9516065, 1984.
Covino, T. P., Bernhardt, E. S., and Heffernan, J. B.: Measuring and interpreting relationships between nutrient supply, demand, and limitation, Freshw. Sci., 37, 448–455, https://doi.org/10.1086/699202, 2018.
Ensign, S. H. and Doyle, M. W.: Nutrient spiraling in streams and river networks, J. Geophys. Res.-Biogeo., 111, G04009, https://doi.org/10.1029/2005JG000114, 2006.
Descy, J.-P., Leitão, M., Everbecq, E., Smitz, J. S., and Deliege, J.-F.: Phytoplankton of the River Loire, France: a biodiversity and modelling study, J. Plankton Res., 34, 120–135, https://doi.org/10.1093/plankt/fbr085, 2011.
Desmet, N. J. S., Van Belleghem, S., Seuntjens, P., Bouma, T. J., Buis, K. and Meire, P.: Quantification of the impact of macrophytes on oxygen dynamics and nitrogen retention in a vegetated lowland river, Phys. Chem. Earth Pt. A/B/C, 36, 479–489, https://doi.org/10.1016/j.pce.2008.06.002, 2011.
Durand, P., Breuer, L., Johnes, P. J., Billen, G., Butturini, A., Pinay, G., van Grinsven, H., Garnier, J., Rivett, M., Reay, D. S., Curtis, C., Siemens, J., Maberly, S., Kaste, Ø., Humborg, C., Loeb, R., de Klein, J., Hejzlar, J., Skoulikidis, N., Kortelainen, P., Lepistö, A., and Wright, R.: 7 – Nitrogen processes in aquatic ecosystems, in: The European Nitrogen Assessment: Sources, Effects and Policy Perspectives, edited by: Bleeker, A., Grizzetti, B., Howard, C. M., Billen, G., van Grinsven, H., Erisman, J. W., Sutton, M. A., and Grennfelt, P., Cambridge University Press, Cambridge, UK, 126–146, https://doi.org/10.1017/CBO9780511976988.010, 2011.
DWD – German Meteorological Service: Index of/climate_environment/CDC/observations_germany/climate/, DWD [data set], https://opendata.dwd.de/, last access: 7 November 2022.
Glasaitė, R. and Šatkauskienė, I.: Periphyton composition and diversity in the Kaunas Lagoon and the Nemunas River, Biologija, 59, 141–150, https://doi.org/10.6001/biologija.v59i2.2746, 2013.
Hall Jr, R. O., Tank, J. L., Sobota, D. J., Mulholland, P. J., O'Brien, J. M., Dodds, W. K., Webster, J. R., Valett, H. M., Poole, G. C., Peterson, B. J., Meyer, J. L., McDowell, W. H., Johnson, S. L., Hamilton, S. K., Grimm, N. B., Gregory, S. V., Dahm, C. N., Cooper, L. W., Ashkenas, L. R., Thomas, S. M., Sheibley, R. W., Potter, J. D., Niederlehner, B. R., Johnson, L. T., Helton, A. M., Crenshaw, C. M., Burgin, A. J., Bernot, M. J., Beaulieu, J. J., and Arangob, C. P.: Nitrate removal in stream ecosystems measured by 15N addition experiments: Total uptake, Limnol. Oceanogr., 54, 653–665, https://doi.org/10.4319/lo.2009.54.3.0653, 2009.
Hamilton, D. P., Carey, C. C., Arvola, L., Arzberger, P., Brewer, C., Cole, J. J., Gaiser, E., Hanson, P. C., Ibelings, B. W., Jennings, E., Kratz, T. K., Lin, F.-P., McBride, C. G., David de Marques, M., Muraoka, K., Nishri, A., Qin, B., Read, J. S., Rose, K. C., Ryder, E., Weathers, K. C., Zhu, G., Trolle, D., and Brookes, J. D.: A Global Lake Ecological Observatory Network (GLEON) for synthesising high-frequency sensor data for validation of deterministic ecological models, Inland Waters, 5, 49–56, https://doi.org/10.5268/IW-5.1.566, 2015.
Hardenbicker, P., Rolinski, S., Weitere, M., and Fischer, H.: Contrasting long-term trends and shifts in phytoplankton dynamics in two large rivers, Int. Rev. Hydrobiol., 99, 287–299, https://doi.org/10.1002/iroh.201301680, 2014.
Heffernan, J. B. and Cohen, M. J.: Direct and indirect coupling of primary production and diel nitrate dynamics in a subtropical spring-fed river, Limnol. Oceanogr., 55, 677–688, https://doi.org/10.4319/lo.2010.55.2.0677, 2010.
Hensley, R. T. and Cohen, M. J.: Nitrate depletion dynamics and primary production in riverine benthic chambers, Freshw. Sci., 39, 169–182, https://doi.org/10.1086/707650, 2020.
Hensley, R. T., Cohen, M. J., and Korhnak, L. V.: Inferring nitrogen removal in large rivers from high-resolution longitudinal profiling, Limnol. Oceanogr., 59, 1152–1170, https://doi.org/10.4319/lo.2014.59.4.1152, 2014.
Hensley, R. T., Kirk, L., Spangler, M., Gooseff, M. N., and Cohen, M. J.: Flow extremes as spatiotemporal control points on river solute fluxes and metabolism, J. Geophys. Res.-Biogeo., 124, 537–555, https://doi.org/10.1029/2018JG004738, 2019.
Huang, J., Yin, H., Jomaa, S., Rode, M., and Zhou, Q.: Limited nitrogen retention in an urban river receiving raw sewage and wastewater treatment plant effluent, Environ. Sci.-Proc. Imp., 21, 1477–1488, https://doi.org/10.1039/C9EM00201D, 2019.
Huang, J., Merchan-Rivera P., Chiogna G., Disse M., and Rode M.: Can high-frequency data enable better parameterization of water quality models and disentangling of DO processes?, EGU General Assembly 2021, Online, 13–30 April 2021, EGU2020-18622, https://doi.org/10.5194/egusphere-egu21-8936, 2021.
Jäger, C. G. and Borchardt, D.: Longitudinal patterns and response lengths of algae in riverine ecosystems: A model analysis emphasising benthic-pelagic interactions, J. Theor. Biol., 442, 66–78, https://doi.org/10.1016/j.jtbi.2018.01.009, 2018.
Kamjunke, N., Mages, M., Büttner, O., Marcus, H., and Weitere, M.: Relationship between the elemental composition of stream biofilms and water chemistry—a catchment approach, Environ. Monit. Assess., 187, 432, https://doi.org/10.1007/s10661-015-4664-6, 2015.
Kamjunke, N., Rode, M., Baborowski, M., Kunz, J. V., Zehner, J., Borchardt, D., and Weitere, M.: High irradiation and low discharge promote the dominant role of phytoplankton in riverine nutrient dynamics, Limnol. Oceanogr., 66, 2648–2660, https://doi.org/10.1002/lno.11778, 2021.
Khorashadi Zadeh, F., Nossent, J., Woldegiorgis, B. T., Bauwens, W., and van Griensven, A.: Impact of measurement error and limited data frequency on parameter estimation and uncertainty quantification, Environ. Model. Softw., 118, 35–47, https://doi.org/10.1016/j.envsoft.2019.03.022, 2019.
Kunz, J. V., Hensley, R., Brase, L., Borchardt, D., and Rode, M.: High frequency measurements of reach scale nitrogen uptake in a fourth order river with contrasting hydromorphology and variable water chemistry (Weiße Elster, Germany), Water Resour. Res., 53, 328–343, https://doi.org/10.1002/2016WR019355, 2017.
Lepoint, G., Gobert, S., Dauby, P., and Bouquegneau, J.-M.: Contributions of benthic and planktonic primary producers to nitrate and ammonium uptake fluxes in a nutrient-poor shallow coastal area (Corsica, NW Mediterranean), J. Exp. Mar. Biol. Ecol., 302, 107–122, https://doi.org/10.1016/j.jembe.2003.10.005, 2004.
LHW: Niedrigwasserbewirtschaftungsmodell Untere Bode Endbericht, Landesbetrieb für Hochwasserschutz und Wasserwirtschaft Sachsen-Anhalt, Magdeburg, Germany, 2012.
LHW: Hydrologische Situation in Sachsen-Anhalt, https://gld.lhw-sachsen-anhalt.de/, last access: 11 November 2022.
Martin, J. L., Robert B., and Wool, T. A.: WASP7 Benthic Algae – Model Theory and User's Guide, Supplement to Water Analysis Simulation Program (WASP) User Documentation, US Environmental Protection Agency – Region 4, Atlanta, GA, US, 2017.
Matott, L.: OSTRICH: an Optimization Software Tool, Documentation and User's Guide, Version 17.12.19, University at Buffalo Center for Computational Research, USA, https://www.eng.buffalo.edu/~lsmatott/Ostrich/OstrichMain.html (last access: 7 November 2022), 2017.
Minaudo, C., Curie, F., Jullian, Y., Gassama, N., and Moatar, F.: QUAL-NET, a high temporal-resolution eutrophication model for large hydrographic networks, Biogeosciences, 15, 2251–2269, https://doi.org/10.5194/bg-15-2251-2018, 2018.
Minaudo, C., Abonyi, A., Leitão, M., Lançon, A. M., Floury, M., Descy, J.-P. and Moatar, F.: Long-term impacts of nutrient control, climate change, and invasive clams on phytoplankton and cyanobacteria biomass in a large temperate river, Sci. Total Environ., 756, 144074, https://doi.org/10.1016/j.scitotenv.2020.144074, 2021.
Moatar, F., Abbott, B. W., Minaudo, C., Curie, F., and Pinay, G.: Elemental properties, hydrology, and biology interact to shape concentration-discharge curves for carbon, nutrients, sediment, and major ions, Water Resour. Res., 53, 1270–1287, https://doi.org/10.1002/2016WR019635, 2017.
Mulholland, P. J., Helton, A. M., Poole, G. C., Hall, R. O., Hamilton, S. K., Peterson, B. J., Tank, J. L., Ashkenas, L. R., Cooper, L. W., Dahm, C. N., Dodds, W. K., Findlay, S. E. G., Gregory, S. V., Grimm, N. B., Johnson, S. L., McDowell, W. H., Meyer, J. L., Valett, H. M., Webster, J. R., Arango, C. P., Beaulieu, J. J., Bernot, M. J., Burgin, A. J., Crenshaw, C. L., Johnson, L. T., Niederlehner, B. R., O'Brien, J. M., Potter, J. D., Sheibley, R. W., Sobota, D. J., and Thomas, S. M.: Stream denitrification across biomes and its response to anthropogenic nitrate loading, Nature, 452, 202–205, https://doi.org/10.1038/nature06686, 2008.
Pathak, D., Hutchins, M., Brown, L., Loewenthal, M., Scarlett, P., Armstrong, L., Nicholls, D., Bowes, M., and Edwards, F.: Hourly prediction of phytoplankton biomass and its environmental controls in lowland rivers, Water Resour. Res., 57, e2020WR028773, https://doi.org/10.1029/2020WR028773, 2021.
Pianosi, F., Sarrazin, F., and Wagener, T.: A Matlab toolbox for Global Sensitivity Analysis, Environ. Model. Softw. 70, 80–85, https://doi.org/10.1016/j.envsoft.2015.04.009, 2015.
Raimonet, M., Vilmin, L., Flipo, N., Rocher, V., and Laverman, A. M.: Modelling the fate of nitrite in an urbanized river using experimentally obtained nitrifier growth parameters, Water Res., 73, 373–387, https://doi.org/10.1016/j.watres.2015.01.026, 2015.
Reynolds, C. S. and Descy, J. P.: The production, biomass and structure of phytoplankton in large rivers, Large Rivers, 10, 161–187, https://doi.org/10.1127/lr/10/1996/161, 1996.
Riis, T., Dodds, W. K., Kristensen, P. B., and Baisner, A. J.: Nitrogen cycling and dynamics in a macrophyte-rich stream as determined by a release, Freshw. Biol., 57, 1579–1591, https://doi.org/10.1111/j.1365-2427.2012.02819.x, 2012.
Rimet, F., Bouchez, A., and Montuelle, B.: Benthic diatoms and phytoplankton to assess nutrients in a large lake: Complementarity of their use in Lake Geneva (France–Switzerland), Ecol. Indic., 53, 231–239, https://doi.org/10.1016/j.ecolind.2015.02.008, 2015.
Redfield, A. C.: The biological control of chemical factors in the environment, Am. Sci., 46, 230A, 205–221. 1958.
Rode, M., Halbedel née Angelstein, S., Anis, M. R., Borchardt, D., and Weitere, M.: Continuous in-stream assimilatory nitrate uptake from high-frequency sensor measurements, Environ. Sci. Technol., 50, 5685–5694, https://doi.org/10.1021/acs.est.6b00943, 2016a.
Rode, M., Wade, A. J., Cohen, M. J., Hensley, R. T., Bowes, M. J., Kirchner, J. W., Arhonditsis, G. B., Jordan, P., Kronvang, B., Halliday, S. J., Skeffington, R. A., Rozemeijer, J. C., Aubert, A. H., Rinke, K., and Jomaa, S.: Sensors in the stream: the high-frequency wave of the present, Environ. Sci. Technol., 50, 10297–10307, https://doi.org/10.1021/acs.est.6b02155, 2016b.
Rutherford, J. C., Young, R. G., Quinn, J. M., Chapra, S. C., and Wilcock, R. J.: Nutrient attenuation in streams: a simplified model to explain field observations, J. Environ. Eng., 146, 04020092, https://doi.org/10.1061/(ASCE)EE.1943-7870.0001753, 2020.
Tank, J. L., Reisinger, A. J., and Rosi, E. J.: Chapter 31 – Nutrient limitation and uptake, in: Methods in Stream Ecology (Third Edition), edited by: Lamberti, G. A. and and Hauer, F. R., Academic Press, Elsevier, 147–171, https://doi.org/10.1016/B978-0-12-813047-6.00009-7, 2017.
Tank, J. L., Martí, E., Riis, T., von Schiller, D., Reisinger, A. J., Dodds, W. K., Whiles, M. R., Ashkenas, L. R., Bowden, W. B., Collins, S. M., Crenshaw, C. L., Crowl, T. A., Griffiths, N. A., Grimm, N. B., Hamilton, S. K., Johnson, S. L., McDowell, W. H., Norman, B. M., Rosi, E. J., Simon, K. S., Thomas, S. A., and Webster, J. R.: Partitioning assimilatory nitrogen uptake in streams: an analysis of stable isotope tracer additions across continents, Ecol. Monogr., 88, 120–138, https://doi.org/10.1002/ecm.1280, 2018.
UFZ – Helmholtz Centre for Environmental Research: Harz/Central German Lowland Observatory under Terrestrial Environmental Observatories (TERENO), https://www.tereno.net/ddp, last access: 7 November 2022.
US EPA: Water Quality Analysis Simulation Program (WASP), https://www.epa.gov/ceam/water-quality-analysis-simulation-program-wasp, last access: 7 November 2022.
Vannote, R. L., Minshall, G. W., Cummins, K. W., Sedell, J. R., and Cushing, C. E.: The River Continuum Concept, Can. J. Fish. Aquat. Sci., 37, 130–137, https://doi.org/10.1139/f80-017, 1980.
Verstraete, W. and Focht, D. D.: Biochemical ecology of nitrification and denitrification, in: Advances in Microbial Ecology, edited by: Alexander, M., Springer, Boston, MA, US, 135–214, https://doi.org/10.1007/978-1-4615-8219-9_4, 1977.
von Schiller, D., Bernal, S., Sabater, F., and Martí, E.: A round-trip ticket: the importance of release processes for in-stream nutrient spiraling, Freshw. Sci., 34, 20–30, https://doi.org/10.1086/679015, 2015.
Wagenschein, D. and Rode, M.: Modelling the impact of river morphology on nitrogen retention—A case study of the Weisse Elster River (Germany), Ecol. Modell., 211, 224–232, https://doi.org/10.1016/j.ecolmodel.2007.09.009, 2008.
Wool, T., Ambrose, R. B., Martin, J. L., and Comer, E. A.: WASP 8: The Next Generation in the 50-year Evolution of USEPA's Water Quality Model, Water, 12, 1398, https://doi.org/10.3390/w12051398, 2020.
Wool, T. A., Ambrose, R. B., Martin, J. L., and Comer, E. A.: Water Quality Analysis Simulation Program (WASP) Version 6.0 DRAFT: User's Manual, US Environmental Protection Agency – Region 4, Atlanta, GA, US, 2002.
Yang, S., Bertuzzo, E., Büttner, O., Borchardt, D., and Rao, P. S. C.: Emergent spatial patterns of competing benthic and pelagic algae in a river network: A parsimonious basin-scale modeling analysis, Water Res., 193, 116887, https://doi.org/10.1016/j.watres.2021.116887, 2021.
In this study, we set up a water quality model using a 5-year paired high-frequency water quality dataset from a large agricultural stream. The simulations were compared with the 15 min interval measurements and showed very good fits. Based on these, we quantified the N uptake pathway rates and efficiencies at daily, seasonal, and yearly scales. This study offers an overarching understanding of N processing in large agricultural streams across different temporal scales.
In this study, we set up a water quality model using a 5-year paired high-frequency water...