Articles | Volume 20, issue 6
https://doi.org/10.5194/hess-20-2353-2016
© Author(s) 2016. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
https://doi.org/10.5194/hess-20-2353-2016
© Author(s) 2016. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
A meta-analysis and statistical modelling of nitrates in groundwater at the African scale
Issoufou Ouedraogo
CORRESPONDING AUTHOR
Earth and Life Institute, Université catholique de Louvain, Croix
du Sud 2, Box 2, B-1348 Louvain-la-Neuve, Belgium
Marnik Vanclooster
Earth and Life Institute, Université catholique de Louvain, Croix
du Sud 2, Box 2, B-1348 Louvain-la-Neuve, Belgium
Related authors
Issoufou Ouedraogo and Marnik Vanclooster
Proc. IAHS, 384, 69–74, https://doi.org/10.5194/piahs-384-69-2021, https://doi.org/10.5194/piahs-384-69-2021, 2021
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The results of the study have shed light on the pollution problem of groundwater at the pan-African scale. We demonstrated the unambiguous link between population density (urban areas, agricultural activity) and pollution of groundwater. We showed that the machine learning techniques are promising for modelling groundwater degradation at the African scale because of its ability to provide meaningful analysis of nonlinear and complex relationships such as those found in hydrogeological studies.
Elise Verstraeten, Alice Alonso, Louise Collier, and Marnik Vanclooster
Hydrol. Earth Syst. Sci. Discuss., https://doi.org/10.5194/hess-2024-173, https://doi.org/10.5194/hess-2024-173, 2024
Preprint under review for HESS
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This study evaluates the effectiveness of Wallonia's sustainable nitrogen management program against groundwater nitrate contamination, 20 years post-implementation. We analysed nitrate concentration time series from 36 locations, finding a modest overall improvement and variability across sites. Results reveal interrelated controlling factors, with land use and aquifer characteristics being key. Lack of improvement may be due to a time lag before the impact of regulatory measures is observable.
Damien Delforge, Olivier de Viron, Marnik Vanclooster, Michel Van Camp, and Arnaud Watlet
Hydrol. Earth Syst. Sci., 26, 2181–2199, https://doi.org/10.5194/hess-26-2181-2022, https://doi.org/10.5194/hess-26-2181-2022, 2022
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Causal inference methods (CIMs) aim at identifying causal links from temporal dependencies found in time-series data. Using both synthetic data and real-time series from a karst system, we study and discuss the potential of four CIMs to reveal hydrological connections between variables in hydrological systems. Despite the ever-present risk of spurious hydrological connections, our results highlight that the nonlinear and multivariate CIM has a substantially lower false-positive rate.
Issoufou Ouedraogo and Marnik Vanclooster
Proc. IAHS, 384, 69–74, https://doi.org/10.5194/piahs-384-69-2021, https://doi.org/10.5194/piahs-384-69-2021, 2021
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The results of the study have shed light on the pollution problem of groundwater at the pan-African scale. We demonstrated the unambiguous link between population density (urban areas, agricultural activity) and pollution of groundwater. We showed that the machine learning techniques are promising for modelling groundwater degradation at the African scale because of its ability to provide meaningful analysis of nonlinear and complex relationships such as those found in hydrogeological studies.
José Luis Gabriel, Miguel Quemada, Diana Martín-Lammerding, and Marnik Vanclooster
Hydrol. Earth Syst. Sci. Discuss., https://doi.org/10.5194/hess-2018-372, https://doi.org/10.5194/hess-2018-372, 2018
Revised manuscript not accepted
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Cover cropping enhance many agricultural services, but few studies are available on the long term effect on hydraulic properties. Soil water content was monitored daily in a 10-year field experiment and hydraulic properties were determined based on inverse calibration. Cover crop increased of the soil micro- and macro-porosity. Then, the expected cover crop competition for water can be compensated by an improvement of the water retention in the intermediate layers of the soil profile.
Jose Luis Gabriel, Miguel Quemada, Diana Martín-Lammerding, and Marnik Vanclooster
Hydrol. Earth Syst. Sci. Discuss., https://doi.org/10.5194/hess-2017-643, https://doi.org/10.5194/hess-2017-643, 2017
Manuscript not accepted for further review
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Few studies are available allowing to evaluate the impact of cover cropping on the long term change of soil hydrologic functions, so we assessed the changes during a 10-year field experiment. This study shows that the expected cover crop competition for water with the main crop can be compensated by an improvement of the water retention in the intermediate layers of the soil profile, enhancing the hydrologic functions of agricultural soils in regions which often are constrained by water stress.
Natalia Fernández de Vera, Jean Beaujean, Pierre Jamin, David Caterina, Marnik Vanclooster, Alain Dassargues, Ofer Dahan, Frédéric Nguyen, and Serge Brouyère
Hydrol. Earth Syst. Sci. Discuss., https://doi.org/10.5194/hess-2016-79, https://doi.org/10.5194/hess-2016-79, 2016
Revised manuscript not accepted
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Soil and groundwater remediation at industrial contaminated sites require suitable field instrumentation for subsurface characterization. The proposed method provides chemical, hydraulic information and images from the subsurface via customized sensors installed in boreholes. Their installation at a brownfield allows flow and transport characterization of water and contaminants across a heterogeneous subsurface. The results proof the effectiveness of the method for characterization purposes.
F. Wiaux, M. Vanclooster, and K. Van Oost
Biogeosciences, 12, 4637–4649, https://doi.org/10.5194/bg-12-4637-2015, https://doi.org/10.5194/bg-12-4637-2015, 2015
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In this study, we highlight the role of soil physical conditions and gas transfer mechanisms and dynamics in the decomposition and storage of soil organic carbon in subsoil layers. To illustrate it, we measured the time series of soil temperature, moisture and CO2 concentration and calculated CO2 fluxes along 1 m depth soil profiles during 6 months throughout two contrasted soil profiles along a hillslope in the central loess belt of Belgium.
F. Meskini-Vishkaee, M. H. Mohammadi, and M. Vanclooster
Hydrol. Earth Syst. Sci., 18, 4053–4063, https://doi.org/10.5194/hess-18-4053-2014, https://doi.org/10.5194/hess-18-4053-2014, 2014
H. Sellami, I. La Jeunesse, S. Benabdallah, N. Baghdadi, and M. Vanclooster
Hydrol. Earth Syst. Sci., 18, 2393–2413, https://doi.org/10.5194/hess-18-2393-2014, https://doi.org/10.5194/hess-18-2393-2014, 2014
A. P. Tran, M. Vanclooster, and S. Lambot
Hydrol. Earth Syst. Sci., 17, 2543–2556, https://doi.org/10.5194/hess-17-2543-2013, https://doi.org/10.5194/hess-17-2543-2013, 2013
J. Minet, N. E. C. Verhoest, S. Lambot, and M. Vanclooster
Hydrol. Earth Syst. Sci. Discuss., https://doi.org/10.5194/hessd-10-4063-2013, https://doi.org/10.5194/hessd-10-4063-2013, 2013
Revised manuscript has not been submitted
Related subject area
Subject: Water Resources Management | Techniques and Approaches: Modelling approaches
The H2Ours game to explore water use, resources and sustainability: connecting issues in two landscapes in Indonesia
Drainage assessment of irrigation districts: on the precision and accuracy of four parsimonious models
Impact of reservoir evaporation on future water availability in north-eastern Brazil: a multi-scenario assessment
How economically and environmentally viable are multiple dams in the upper Cauvery Basin, India? A hydro-economic analysis using a landscape-based hydrological model
Leveraging a novel hybrid ensemble and optimal interpolation approach for enhanced streamflow and flood prediction
A generalised ecohydrological landscape classification for assessing ecosystem risk in Australia due to an altering water regime
Process-based three-layer synergistic optimal-allocation model for complex water resource systems considering reclaimed water
Assessment of Upscaling Methodologies for Daily Crop Transpiration using Sap-Flows and Two-Source Energy Balance Models in Almonds under Different Water Status and Production Systems
Developing water supply reservoir operating rules for large-scale hydrological modelling
Joint optimal operation of the South-to-North Water Diversion Project considering the evenness of water deficit
Employing the generalized Pareto distribution to analyze extreme rainfall events on consecutive rainy days in Thailand's Chi watershed: implications for flood management
Modeling hydropower operations at the scale of a power grid: a demand-based approach
How to account for irrigation withdrawals in a watershed model
Inferring reservoir filling strategies under limited-data-availability conditions using hydrological modeling and Earth observations: the case of the Grand Ethiopian Renaissance Dam (GERD)
An investigation of anthropogenic influences on hydrologic connectivity using stress tests
Making a case for power-sensitive water modelling: a literature review
The precision of satellite-based net irrigation quantification in the Indus and Ganges basins
Developing a Bayesian network model for understanding river catchment resilience under future change scenarios
Quantifying the trade-offs in re-operating dams for the environment in the Lower Volta River
Dynamically coupling system dynamics and SWAT+ models using Tinamït: application of modular tools for coupled human–water system models
Development of an integrated socio-hydrological modeling framework for assessing the impacts of shelter location arrangement and human behaviors on flood evacuation processes
Cooperation in a transboundary river basin: a large-scale socio-hydrological model of the Eastern Nile
Flexible forecast value metric suitable for a wide range of decisions: application using probabilistic subseasonal streamflow forecasts
An improved model of shade-affected stream temperature in Soil & Water Assessment Tool
Seasonal forecasting of snow resources at Alpine sites
Operationalizing equity in multipurpose water systems
Evaluation of a new observationally based channel parameterization for the National Water Model
High-resolution drought simulations and comparison to soil moisture observations in Germany
Cooperation under conflict: participatory hydrological modeling for science policy dialogues for the Aculeo Lake
Socio-hydrological modeling of the tradeoff between flood control and hydropower provided by the Columbia River Treaty
Challenges and benefits of quantifying irrigation through the assimilation of Sentinel-1 backscatter observations into Noah-MP
A system dynamic model to quantify the impacts of water resources allocation on water–energy–food–society (WEFS) nexus
Net irrigation requirement under different climate scenarios using AquaCrop over Europe
The role of multi-criteria decision analysis in a transdisciplinary process: co-developing a flood forecasting system in western Africa
Unfolding the relationship between seasonal forecast skill and value in hydropower production: a global analysis
Drought impact links to meteorological drought indicators and predictability in Spain
Opportunities for seasonal forecasting to support water management outside the tropics
Probabilistic modelling of the inherent field-level pesticide pollution risk in a small drinking water catchment using spatial Bayesian belief networks
Are maps of nitrate reduction in groundwater altered by climate and land use changes?
Historical simulation of maize water footprints with a new global gridded crop model ACEA
Future upstream water consumption and its impact on downstream water availability in the transboundary Indus Basin
Identifying the dynamic evolution and feedback process of water resources nexus system considering socioeconomic development, ecological protection, and food security: A practical tool for sustainable water use
Optimizing a backscatter forward operator using Sentinel-1 data over irrigated land
Robustness of a parsimonious subsurface drainage model at the French national scale
Spatially distributed impacts of climate change and groundwater demand on the water resources in a wadi system
Delineation of dew formation zones in Iran using long-term model simulations and cluster analysis
Streamflow estimation at partially gaged sites using multiple-dependence conditions via vine copulas
Water resources management and dynamic changes in water politics in the transboundary river basins of Central Asia
Assessing interannual variability in nitrogen sourcing and retention through hybrid Bayesian watershed modeling
Minimizing the impact of vacating instream storage of a multi-reservoir system: a trade-off study of water supply and empty flushing
Lisa Tanika, Rika Ratna Sari, Arief Lukman Hakim, Meine van Noordwijk, Marielos Peña-Claros, Beria Leimona, Edi Purwanto, and Erika N. Speelman
Hydrol. Earth Syst. Sci., 28, 3807–3835, https://doi.org/10.5194/hess-28-3807-2024, https://doi.org/10.5194/hess-28-3807-2024, 2024
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The H2Ours game is designed to facilitate knowledge transfer and sharing among stakeholders to trigger commitment and collaborative action to restore hydrological conditions. The adaptability of the H2Ours game was proven in two different landscapes: groundwater recharge in upper to middle sub-watersheds with (over)use of water in the lowland zone and a peatland with drainage, rewetting, oil palm conversion and fire as issues. The game evaluation shows that the H2Ours game meets its purpose.
Pierre Laluet, Luis Olivera-Guerra, Víctor Altés, Vincent Rivalland, Alexis Jeantet, Julien Tournebize, Omar Cenobio-Cruz, Anaïs Barella-Ortiz, Pere Quintana-Seguí, Josep Maria Villar, and Olivier Merlin
Hydrol. Earth Syst. Sci., 28, 3695–3716, https://doi.org/10.5194/hess-28-3695-2024, https://doi.org/10.5194/hess-28-3695-2024, 2024
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Monitoring agricultural drainage flow in irrigated areas is key to water and soil management. In this paper, four simple drainage models are evaluated on two irrigated sub-basins where drainage flow is measured daily. The evaluation of their precision shows that they simulate drainage very well when calibrated with drainage data and that one of them is slightly better. The evaluation of their accuracy shows that only one model can provide rough drainage estimates without calibration data.
Gláuber Pontes Rodrigues, Arlena Brosinsky, Ítalo Sampaio Rodrigues, George Leite Mamede, and José Carlos de Araújo
Hydrol. Earth Syst. Sci., 28, 3243–3260, https://doi.org/10.5194/hess-28-3243-2024, https://doi.org/10.5194/hess-28-3243-2024, 2024
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The research focuses on a 4-million-inhabitant tropical region supplied by a network of open-water reservoirs where the dry season lasts for 8 months (Jun−Dec). We analysed the impact of four climate change scenarios on the evaporation rate and the associated availability (water yield distributed per year). The worst-case scenario shows that by the end of the century (2071−2099), the evaporation rate in the dry season could increase by 6 %, which would reduce stored water by about 80 %.
Anjana Ekka, Yong Jiang, Saket Pande, and Pieter van der Zaag
Hydrol. Earth Syst. Sci., 28, 3219–3241, https://doi.org/10.5194/hess-28-3219-2024, https://doi.org/10.5194/hess-28-3219-2024, 2024
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For the first time, we analyse the economic and ecological performance of existing multiple big reservoirs on a daily timescale for a major river basin (upper Cauvery) in India, where pre-intervention data were not available but where there are increasing calls for such assessments. Results show that smaller reservoirs on smaller streams that maximize the economic value of stored water are better for the basin economy and the environment. The approach can help to prioritize dam removals.
Mohamad El Gharamti, Arezoo Rafieeinasab, and James L. McCreight
Hydrol. Earth Syst. Sci., 28, 3133–3159, https://doi.org/10.5194/hess-28-3133-2024, https://doi.org/10.5194/hess-28-3133-2024, 2024
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This study introduces a hybrid data assimilation scheme for precise streamflow predictions during intense rainfall and hurricanes. Tested in real events, it outperforms traditional methods by up to 50 %, utilizing ensemble and climatological background covariances. The adaptive algorithm ensures reliability with a small ensemble, offering improved forecasts up to 18 h in advance, marking a significant advancement in flood prediction capabilities.
Alexander Herr, Linda E. Merrin, Patrick J. Mitchell, Anthony P. O'Grady, Kate L. Holland, Richard E. Mount, David A. Post, Chris R. Pavey, and Ashley D. Sparrow
Hydrol. Earth Syst. Sci., 28, 1957–1979, https://doi.org/10.5194/hess-28-1957-2024, https://doi.org/10.5194/hess-28-1957-2024, 2024
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We develop an ecohydrological classification for regions with limited hydrological records. It provides causal links of landscape features and their water requirement. The classification is an essential framework for modelling the impact of future coal resource developments via water on the features. A rule set combines diverse data with prioritisation, resulting in a transparent, repeatable and adjustable approach. We show examples of linking ecohydrology with environmental impacts.
Jing Liu, Yue-Ping Xu, Wei Zhang, Shiwu Wang, and Siwei Chen
Hydrol. Earth Syst. Sci., 28, 1325–1350, https://doi.org/10.5194/hess-28-1325-2024, https://doi.org/10.5194/hess-28-1325-2024, 2024
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Applying optimal water allocation models to simultaneously enable economic benefits, water preferences, and environmental demands at different decision levels, timescales, and regions is a challenge. In this study, a process-based three-layer synergistic optimal-allocation model (PTSOA) is established to achieve these goals. Reused, reclaimed water is also coupled to capture environmentally friendly solutions. Network analysis was introduced to reduce competition among different stakeholders.
Manuel Quintanilla-Albornoz, Xavier Miarnau, Ana Pelechá, Héctor Nieto, and Joaquim Bellvert
Hydrol. Earth Syst. Sci. Discuss., https://doi.org/10.5194/hess-2024-5, https://doi.org/10.5194/hess-2024-5, 2024
Revised manuscript accepted for HESS
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Remote sensing can be a helpful tool for monitoring crop transpiration (T) for agricultural water management. Since remote sensing provides instantaneous data, upscaling techniques are required to estimate T on a daily scale. This study assesses optimal image acquisition times and four upscaling approaches to estimate daily T. The results indicate that the main errors derive from measurement time and water stress levels, which can be mitigated by choosing a proper upscaling approach.
Saskia Salwey, Gemma Coxon, Francesca Pianosi, Rosanna Lane, Chris Hutton, Michael Bliss Singer, Hilary McMillan, and Jim Freer
EGUsphere, https://doi.org/10.5194/egusphere-2024-326, https://doi.org/10.5194/egusphere-2024-326, 2024
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Reservoirs are essential for water resource management and can significantly impact downstream flow. However, representing reservoirs in hydrological models can be challenging, particularly across large-scales. We design a new, simple method for simulating river flow downstream of water supply reservoirs using only open-access data. We demonstrate the approach in 264 reservoir catchments across Great Britain where we can significantly improve the simulation of reservoir-impacted flow.
Bing-Yi Zhou, Guo-Hua Fang, Xin Li, Jian Zhou, and Hua-Yu Zhong
Hydrol. Earth Syst. Sci., 28, 817–832, https://doi.org/10.5194/hess-28-817-2024, https://doi.org/10.5194/hess-28-817-2024, 2024
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The current unreasonable inter-basin water transfer operation leads to the problem of spatial and temporal imbalances in water allocation. This paper defines a water deficit evenness index and incorporates it into a joint optimization model for the Jiangsu section of the South-to-North Water Diversion Project considering ecology and economy. At the same time, the lake storage capacity performs well, and the water transfer efficiency of the river is significantly improved.
Tossapol Phoophiwfa, Prapawan Chomphuwiset, Thanawan Prahadchai, Jeong-Soo Park, Arthit Apichottanakul, Watchara Theppang, and Piyapatr Busababodhin
Hydrol. Earth Syst. Sci., 28, 801–816, https://doi.org/10.5194/hess-28-801-2024, https://doi.org/10.5194/hess-28-801-2024, 2024
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This study examines the impact of extreme rainfall events on flood risk management in Thailand's Chi watershed. By analyzing historical data, we identified regions, notably Udon Thani and Chaiyaphum, with a high risk of flash flooding. To aid in flood risk assessment, visual maps were created. The study underscores the importance of preparing for extreme rainfall events, particularly in the context of climate change, to effectively mitigate potential flood damage.
Laure Baratgin, Jan Polcher, Patrice Dumas, and Philippe Quirion
EGUsphere, https://doi.org/10.5194/egusphere-2023-3106, https://doi.org/10.5194/egusphere-2023-3106, 2024
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Hydrological modeling is valuable for estimating the possible impacts of climate change on hydropower generation. In this study, we present a more comprehensive approach to model the management of hydroelectric reservoirs. The total power-grid demand is distributed to the various power plants according to their reservoir states to compute their release. The method is tested on France, and demonstrates that it succeeds in reproducing the observed behavior of reservoirs.
Elisabeth Brochet, Youen Grusson, Sabine Sauvage, Ludovic Lhuissier, and Valérie Demarez
Hydrol. Earth Syst. Sci., 28, 49–64, https://doi.org/10.5194/hess-28-49-2024, https://doi.org/10.5194/hess-28-49-2024, 2024
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This study aims to take into account irrigation withdrawals in a watershed model. The model we used combines agriculture and hydrological modeling. Two different crop models were compared, the first based on air temperature and the second based on Sentinel-2 satellite data. Results show that including remote sensing data leads to better emergence dates. Both methods allow us to simulate the daily irrigation withdrawals and downstream flow with a good accuracy, especially during low-flow periods.
Awad M. Ali, Lieke A. Melsen, and Adriaan J. Teuling
Hydrol. Earth Syst. Sci., 27, 4057–4086, https://doi.org/10.5194/hess-27-4057-2023, https://doi.org/10.5194/hess-27-4057-2023, 2023
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Using a new approach based on a combination of modeling and Earth observation, useful information about the filling of the Grand Ethiopian Renaissance Dam can be obtained with limited data and proper rainfall selection. While the monthly streamflow into Sudan has decreased significantly (1.2 × 109–5 × 109 m3) with respect to the non-dam scenario, the negative impact has been masked due to higher-than-average rainfall. We reveal that the dam will need 3–5 more years to complete filling.
Amelie Herzog, Jost Hellwig, and Kerstin Stahl
Hydrol. Earth Syst. Sci. Discuss., https://doi.org/10.5194/hess-2023-243, https://doi.org/10.5194/hess-2023-243, 2023
Revised manuscript accepted for HESS
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We investigated the influence of anthropogenic water withdrawals and climatic changes on streambed drying the Dreisam valley (24 km²) in Germany by means of physical modeling. The model was able to reproduce streambed drying at 50 % of locations. Our results show that groundwater withdrawals intensifiy riverbed drying on short timescales during phases with low groundwater levels at specific locations. At some upstream locations however, climatic preconditions are the primary influencing factor.
Rozemarijn ter Horst, Rossella Alba, Jeroen Vos, Maria Rusca, Jonatan Godinez-Madrigal, Lucie V. Babel, Gert Jan Veldwisch, Jean-Philippe Venot, Bruno Bonté, David W. Walker, and Tobias Krueger
Hydrol. Earth Syst. Sci. Discuss., https://doi.org/10.5194/hess-2023-164, https://doi.org/10.5194/hess-2023-164, 2023
Revised manuscript accepted for HESS
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The exact power of models often remains hidden, especially when neutrality is claimed. Our review of 49 scientific articles shows that in scientific literature little attention is given to the power of hydrological models to influence development processes and outcomes. However, that there is a lot to learn from those who are openly reflexive. Based on lessons from the review, we call for power-sensitive modelling which means that people are critical about how models made and with what effects.
Søren J. Kragh, Rasmus Fensholt, Simon Stisen, and Julian Koch
Hydrol. Earth Syst. Sci., 27, 2463–2478, https://doi.org/10.5194/hess-27-2463-2023, https://doi.org/10.5194/hess-27-2463-2023, 2023
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This study investigates the precision of irrigation estimates from a global hotspot of unsustainable irrigation practice, the Indus and Ganges basins. We show that irrigation water use can be estimated with high precision by comparing satellite and rainfed hydrological model estimates of evapotranspiration. We believe that our work can support sustainable water resource management, as it addresses the uncertainty of a key component of the water balance that remains challenging to quantify.
Kerr J. Adams, Christopher A. J. Macleod, Marc J. Metzger, Nicola Melville, Rachel C. Helliwell, Jim Pritchard, and Miriam Glendell
Hydrol. Earth Syst. Sci., 27, 2205–2225, https://doi.org/10.5194/hess-27-2205-2023, https://doi.org/10.5194/hess-27-2205-2023, 2023
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We applied participatory methods to create a hybrid equation-based Bayesian network (BN) model to increase stakeholder understanding of catchment-scale resilience to the impacts of both climatic and socio-economic stressors to a 2050 time horizon. Our holistic systems-thinking approach enabled stakeholders to gain new perspectives on how future scenarios may influence their specific sectors and how their sector impacted other sectors and environmental conditions within the catchment system.
Afua Owusu, Jazmin Zatarain Salazar, Marloes Mul, Pieter van der Zaag, and Jill Slinger
Hydrol. Earth Syst. Sci., 27, 2001–2017, https://doi.org/10.5194/hess-27-2001-2023, https://doi.org/10.5194/hess-27-2001-2023, 2023
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The construction of two dams in the Lower Volta River, Ghana, adversely affected downstream riverine ecosystems and communities. In contrast, Ghana has enjoyed vast economic benefits from the dams. Herein lies the challenge; there exists a trade-off between water for river ecosystems and water for anthropogenic water demands such hydropower. In this study, we quantify these trade-offs and show that there is room for providing environmental flows under current and future climatic conditions.
Joel Z. Harms, Julien J. Malard-Adam, Jan F. Adamowski, Ashutosh Sharma, and Albert Nkwasa
Hydrol. Earth Syst. Sci., 27, 1683–1693, https://doi.org/10.5194/hess-27-1683-2023, https://doi.org/10.5194/hess-27-1683-2023, 2023
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To facilitate the meaningful participation of stakeholders in water management, model choice is crucial. We show how system dynamics models (SDMs), which are very visual and stakeholder-friendly, can be automatically combined with physically based hydrological models that may be more appropriate for modelling the water processes of a human–water system. This allows building participatory SDMs with stakeholders and delegating hydrological components to an external hydrological model.
Erhu Du, Feng Wu, Hao Jiang, Naliang Guo, Yong Tian, and Chunmiao Zheng
Hydrol. Earth Syst. Sci., 27, 1607–1626, https://doi.org/10.5194/hess-27-1607-2023, https://doi.org/10.5194/hess-27-1607-2023, 2023
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This study develops an integrated socio-hydrological modeling framework that can simulate the entire flood management processes, including flood inundation, flood management policies, public responses, and evacuation activities. The model is able to holistically examine flood evacuation performance under the joint impacts of hydrological conditions, management policies (i.e., shelter location distribution), and human behaviors (i.e., evacuation preparation time and route-searching strategy).
Mohammad Ghoreishi, Amin Elshorbagy, Saman Razavi, Günter Blöschl, Murugesu Sivapalan, and Ahmed Abdelkader
Hydrol. Earth Syst. Sci., 27, 1201–1219, https://doi.org/10.5194/hess-27-1201-2023, https://doi.org/10.5194/hess-27-1201-2023, 2023
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The study proposes a quantitative model of the willingness to cooperate in the Eastern Nile River basin. Our results suggest that the 2008 food crisis may account for Sudan recovering its willingness to cooperate with Ethiopia. Long-term lack of trust among the riparian countries may have reduced basin-wide cooperation. The model can be used to explore the effects of changes in future dam operations and other management decisions on the emergence of basin cooperation.
Richard Laugesen, Mark Thyer, David McInerney, and Dmitri Kavetski
Hydrol. Earth Syst. Sci., 27, 873–893, https://doi.org/10.5194/hess-27-873-2023, https://doi.org/10.5194/hess-27-873-2023, 2023
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Forecasts may be valuable for user decisions, but current practice to quantify it has critical limitations. This study introduces RUV (relative utility value, a new metric that can be tailored to specific decisions and decision-makers. It illustrates how critical this decision context is when evaluating forecast value. This study paves the way for agencies to tailor the evaluation of their services to customer decisions and researchers to study model improvements through the lens of user impact.
Efrain Noa-Yarasca, Meghna Babbar-Sebens, and Chris Jordan
Hydrol. Earth Syst. Sci., 27, 739–759, https://doi.org/10.5194/hess-27-739-2023, https://doi.org/10.5194/hess-27-739-2023, 2023
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Riparian vegetation has been identified as a strategy to control rising stream temperatures by shading streams. Riparian vegetation is included within a sub-basin-scale hydrological model and evaluated for full and efficient restoration scenarios. Results showed average temperature reductions of 0.91 and 0.86 °C for full and efficient riparian restoration, respectively. Notwithstanding the similar benefits, efficient restoration was 14.4 % cheaper than full riparian vegetation restoration.
Silvia Terzago, Giulio Bongiovanni, and Jost von Hardenberg
Hydrol. Earth Syst. Sci., 27, 519–542, https://doi.org/10.5194/hess-27-519-2023, https://doi.org/10.5194/hess-27-519-2023, 2023
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Reliable seasonal forecasts of the abundance of mountain snowpack over the winter/spring ahead provide valuable information for water management, hydropower production and ski tourism. We present a climate service prototype to generate multi-model ensemble seasonal forecasts of mountain snow depth, based on Copernicus seasonal forecast system meteorological data used to force the SNOWPACK model. The prototype shows skill at predicting snow depth below and above normal and extremely dry seasons.
Guang Yang, Matteo Giuliani, and Andrea Castelletti
Hydrol. Earth Syst. Sci., 27, 69–81, https://doi.org/10.5194/hess-27-69-2023, https://doi.org/10.5194/hess-27-69-2023, 2023
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Participatory decision-making is a well-established approach to address the increasing pressure on water systems that searches for system-wise efficient solutions but often does not quantify how the resulting benefits are distributed across stakeholders. In this work, we show how including equity principles into the design of water system operations enriches the solution space by generating more compromise solutions that balance efficiency and justice.
Aaron Heldmyer, Ben Livneh, James McCreight, Laura Read, Joseph Kasprzyk, and Toby Minear
Hydrol. Earth Syst. Sci., 26, 6121–6136, https://doi.org/10.5194/hess-26-6121-2022, https://doi.org/10.5194/hess-26-6121-2022, 2022
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Measurements of channel characteristics are important for accurate forecasting in the NOAA National Water Model (NWM) but are scarcely available. We seek to improve channel representativeness in the NWM by updating channel geometry and roughness parameters using a large, previously unpublished, dataset of approximately 48 000 gauges. We find that the updated channel parameterization from this new dataset leads to improvements in simulated streamflow performance and channel representation.
Friedrich Boeing, Oldrich Rakovec, Rohini Kumar, Luis Samaniego, Martin Schrön, Anke Hildebrandt, Corinna Rebmann, Stephan Thober, Sebastian Müller, Steffen Zacharias, Heye Bogena, Katrin Schneider, Ralf Kiese, Sabine Attinger, and Andreas Marx
Hydrol. Earth Syst. Sci., 26, 5137–5161, https://doi.org/10.5194/hess-26-5137-2022, https://doi.org/10.5194/hess-26-5137-2022, 2022
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In this paper, we deliver an evaluation of the second generation operational German drought monitor (https://www.ufz.de/duerremonitor) with a state-of-the-art compilation of observed soil moisture data from 40 locations and four different measurement methods in Germany. We show that the expressed stakeholder needs for higher resolution drought information at the one-kilometer scale can be met and that the agreement of simulated and observed soil moisture dynamics can be moderately improved.
Anahi Ocampo-Melgar, Pilar Barría, Cristián Chadwick, and Cesar Rivas
Hydrol. Earth Syst. Sci., 26, 5103–5118, https://doi.org/10.5194/hess-26-5103-2022, https://doi.org/10.5194/hess-26-5103-2022, 2022
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This article examines how a hydrological model exploring the causes of a lake desiccation was turned into a 5-step participatory process to better adjust the model to address questions that were causing suspicions and conflicts in the community. Although the process was key in finding a combination of strategies that were of moderate impact and higher local acceptability, we address the challenges of such collaboration in modeling when conflict is deeply embedded in the context.
Ashish Shrestha, Felipe Augusto Arguello Souza, Samuel Park, Charlotte Cherry, Margaret Garcia, David J. Yu, and Eduardo Mario Mendiondo
Hydrol. Earth Syst. Sci., 26, 4893–4917, https://doi.org/10.5194/hess-26-4893-2022, https://doi.org/10.5194/hess-26-4893-2022, 2022
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Equitable sharing of benefits is key to successful cooperation in transboundary water resource management. However, external changes can shift the split of benefits and shifts in the preferences regarding how an actor’s benefits compare to the other’s benefits. To understand how these changes can impact the robustness of cooperative agreements, we develop a socio-hydrological system dynamics model of the benefit sharing provision of the Columbia River Treaty and assess a series of scenarios.
Sara Modanesi, Christian Massari, Michel Bechtold, Hans Lievens, Angelica Tarpanelli, Luca Brocca, Luca Zappa, and Gabriëlle J. M. De Lannoy
Hydrol. Earth Syst. Sci., 26, 4685–4706, https://doi.org/10.5194/hess-26-4685-2022, https://doi.org/10.5194/hess-26-4685-2022, 2022
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Given the crucial impact of irrigation practices on the water cycle, this study aims at estimating irrigation through the development of an innovative data assimilation system able to ingest high-resolution Sentinel-1 radar observations into the Noah-MP land surface model. The developed methodology has important implications for global water resource management and the comprehension of human impacts on the water cycle and identifies main challenges and outlooks for future research.
Yujie Zeng, Dedi Liu, Shenglian Guo, Lihua Xiong, Pan Liu, Jiabo Yin, and Zhenhui Wu
Hydrol. Earth Syst. Sci., 26, 3965–3988, https://doi.org/10.5194/hess-26-3965-2022, https://doi.org/10.5194/hess-26-3965-2022, 2022
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The sustainability of the water–energy–food (WEF) nexus remains challenge, as interactions between WEF and human sensitivity and water resource allocation in water systems are often neglected. We incorporated human sensitivity and water resource allocation into a WEF nexus and assessed their impacts on the integrated system. This study can contribute to understanding the interactions across the water–energy–food–society nexus and improving the efficiency of resource management.
Louise Busschaert, Shannon de Roos, Wim Thiery, Dirk Raes, and Gabriëlle J. M. De Lannoy
Hydrol. Earth Syst. Sci., 26, 3731–3752, https://doi.org/10.5194/hess-26-3731-2022, https://doi.org/10.5194/hess-26-3731-2022, 2022
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Increasing amounts of water are used for agriculture. Therefore, we looked into how irrigation requirements will evolve under a changing climate over Europe. Our results show that, by the end of the century and under high emissions, irrigation water will increase by 30 % on average compared to the year 2000. Also, the irrigation requirement is likely to vary more from 1 year to another. However, if emissions are mitigated, these effects are reduced.
Judit Lienert, Jafet C. M. Andersson, Daniel Hofmann, Francisco Silva Pinto, and Martijn Kuller
Hydrol. Earth Syst. Sci., 26, 2899–2922, https://doi.org/10.5194/hess-26-2899-2022, https://doi.org/10.5194/hess-26-2899-2022, 2022
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Many western Africans encounter serious floods every year. The FANFAR project co-designed a pre-operational flood forecasting system (FEWS) with 50 key western African stakeholders. Participatory multi-criteria decision analysis (MCDA) helped prioritize a FEWS that meets their needs: it should provide accurate, clear, and timely flood risk information and work reliably in tough conditions. As a theoretical contribution, we propose an assessment framework for transdisciplinary hydrology research.
Donghoon Lee, Jia Yi Ng, Stefano Galelli, and Paul Block
Hydrol. Earth Syst. Sci., 26, 2431–2448, https://doi.org/10.5194/hess-26-2431-2022, https://doi.org/10.5194/hess-26-2431-2022, 2022
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To fully realize the potential of seasonal streamflow forecasts in the hydropower industry, we need to understand the relationship between reservoir design specifications, forecast skill, and value. Here, we rely on realistic forecasts and simulated hydropower operations for 753 dams worldwide to unfold such relationship. Our analysis shows how forecast skill affects hydropower production, what type of dams are most likely to benefit from seasonal forecasts, and where these dams are located.
Herminia Torelló-Sentelles and Christian L. E. Franzke
Hydrol. Earth Syst. Sci., 26, 1821–1844, https://doi.org/10.5194/hess-26-1821-2022, https://doi.org/10.5194/hess-26-1821-2022, 2022
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Drought affects many regions worldwide, and future climate projections imply that drought severity and frequency will increase. Hence, the impacts of drought on the environment and society will also increase considerably. Monitoring and early warning systems for drought rely on several indicators; however, assessments on how these indicators are linked to impacts are still lacking. Our results show that meteorological indices are best linked to impact occurrences.
Leah A. Jackson-Blake, François Clayer, Elvira de Eyto, Andrew S. French, María Dolores Frías, Daniel Mercado-Bettín, Tadhg Moore, Laura Puértolas, Russell Poole, Karsten Rinke, Muhammed Shikhani, Leon van der Linden, and Rafael Marcé
Hydrol. Earth Syst. Sci., 26, 1389–1406, https://doi.org/10.5194/hess-26-1389-2022, https://doi.org/10.5194/hess-26-1389-2022, 2022
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We explore, together with stakeholders, whether seasonal forecasting of water quantity, quality, and ecology can help support water management at five case study sites, primarily in Europe. Reliable forecasting, a season in advance, has huge potential to improve decision-making. However, managers were reluctant to use the forecasts operationally. Key barriers were uncertainty and often poor historic performance. The importance of practical hands-on experience was also highlighted.
Mads Troldborg, Zisis Gagkas, Andy Vinten, Allan Lilly, and Miriam Glendell
Hydrol. Earth Syst. Sci., 26, 1261–1293, https://doi.org/10.5194/hess-26-1261-2022, https://doi.org/10.5194/hess-26-1261-2022, 2022
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Pesticides continue to pose a threat to surface water quality worldwide. Here, we present a spatial Bayesian belief network (BBN) for assessing inherent pesticide risk to water quality. The BBN was applied in a small catchment with limited data to simulate the risk of five pesticides and evaluate the likely effectiveness of mitigation measures. The probabilistic graphical model combines diverse data and explicitly accounts for uncertainties, which are often ignored in pesticide risk assessments.
Ida Karlsson Seidenfaden, Torben Obel Sonnenborg, Jens Christian Refsgaard, Christen Duus Børgesen, Jørgen Eivind Olesen, and Dennis Trolle
Hydrol. Earth Syst. Sci., 26, 955–973, https://doi.org/10.5194/hess-26-955-2022, https://doi.org/10.5194/hess-26-955-2022, 2022
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This study investigates how the spatial nitrate reduction in the subsurface may shift under changing climate and land use conditions. This change is investigated by comparing maps showing the spatial nitrate reduction in an agricultural catchment for current conditions, with maps generated for future projected climate and land use conditions. Results show that future climate flow paths may shift the catchment reduction noticeably, while implications of land use changes were less substantial.
Oleksandr Mialyk, Joep F. Schyns, Martijn J. Booij, and Rick J. Hogeboom
Hydrol. Earth Syst. Sci., 26, 923–940, https://doi.org/10.5194/hess-26-923-2022, https://doi.org/10.5194/hess-26-923-2022, 2022
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As the global demand for crops is increasing, it is vital to understand spatial and temporal patterns of crop water footprints (WFs). Previous studies looked into spatial patterns but not into temporal ones. Here, we present a new process-based gridded crop model to simulate WFs and apply it for maize in 1986–2016. We show that despite the average unit WF reduction (−35 %), the global WF of maize production has increased (+50 %), which might harm ecosystems and human livelihoods in some regions.
Wouter J. Smolenaars, Sanita Dhaubanjar, Muhammad K. Jamil, Arthur Lutz, Walter Immerzeel, Fulco Ludwig, and Hester Biemans
Hydrol. Earth Syst. Sci., 26, 861–883, https://doi.org/10.5194/hess-26-861-2022, https://doi.org/10.5194/hess-26-861-2022, 2022
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The arid plains of the lower Indus Basin rely heavily on the water provided by the mountainous upper Indus. Rapid population growth in the upper Indus is expected to increase the water that is consumed there. This will subsequently reduce the water that is available for the downstream plains, where the population and water demand are also expected to grow. In future, this may aggravate tensions over the division of water between the countries that share the Indus Basin.
Yaogeng Tan, Zengchuan Dong, Sandra M. Guzman, Xinkui Wang, and Wei Yan
Hydrol. Earth Syst. Sci., 25, 6495–6522, https://doi.org/10.5194/hess-25-6495-2021, https://doi.org/10.5194/hess-25-6495-2021, 2021
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The rapid increase in economic development and urbanization is contributing to the imbalances and conflicts between water supply and demand and further deteriorates river ecological health, which intensifies their interactions and causes water unsustainability. This paper proposes a methodology for sustainable development of water resources, considering socioeconomic development, food safety, and ecological protection, and the dynamic interactions across those water users are further assessed.
Sara Modanesi, Christian Massari, Alexander Gruber, Hans Lievens, Angelica Tarpanelli, Renato Morbidelli, and Gabrielle J. M. De Lannoy
Hydrol. Earth Syst. Sci., 25, 6283–6307, https://doi.org/10.5194/hess-25-6283-2021, https://doi.org/10.5194/hess-25-6283-2021, 2021
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Worldwide, the amount of water used for agricultural purposes is rising and the quantification of irrigation is becoming a crucial topic. Land surface models are not able to correctly simulate irrigation. Remote sensing observations offer an opportunity to fill this gap as they are directly affected by irrigation. We equipped a land surface model with an observation operator able to transform Sentinel-1 backscatter observations into realistic vegetation and soil states via data assimilation.
Alexis Jeantet, Hocine Henine, Cédric Chaumont, Lila Collet, Guillaume Thirel, and Julien Tournebize
Hydrol. Earth Syst. Sci., 25, 5447–5471, https://doi.org/10.5194/hess-25-5447-2021, https://doi.org/10.5194/hess-25-5447-2021, 2021
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The hydrological subsurface drainage model SIDRA-RU is assessed at the French national scale, using a unique database representing the large majority of the French drained areas. The model is evaluated following its capacity to simulate the drainage discharge variability and the annual drained water balance. Eventually, the temporal robustness of SIDRA-RU is assessed to demonstrate the utility of this model as a long-term management tool.
Nariman Mahmoodi, Jens Kiesel, Paul D. Wagner, and Nicola Fohrer
Hydrol. Earth Syst. Sci., 25, 5065–5081, https://doi.org/10.5194/hess-25-5065-2021, https://doi.org/10.5194/hess-25-5065-2021, 2021
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In this study, we assessed the sustainability of water resources in a wadi region with the help of a hydrologic model. Our assessment showed that the increases in groundwater demand and consumption exacerbate the negative impact of climate change on groundwater sustainability and hydrologic regime alteration. These alterations have severe consequences for a downstream wetland and its ecosystem. The approach may be applicable in other wadi regions with different climate and water use systems.
Nahid Atashi, Dariush Rahimi, Victoria A. Sinclair, Martha A. Zaidan, Anton Rusanen, Henri Vuollekoski, Markku Kulmala, Timo Vesala, and Tareq Hussein
Hydrol. Earth Syst. Sci., 25, 4719–4740, https://doi.org/10.5194/hess-25-4719-2021, https://doi.org/10.5194/hess-25-4719-2021, 2021
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Dew formation potential during a long-term period (1979–2018) was assessed in Iran to identify dew formation zones and to investigate the impacts of long-term variation in meteorological parameters on dew formation. Six dew formation zones were identified based on cluster analysis of the time series of the simulated dew yield. The distribution of dew formation zones in Iran was closely aligned with topography and sources of moisture. The dew formation trend was significantly negative.
Kuk-Hyun Ahn
Hydrol. Earth Syst. Sci., 25, 4319–4333, https://doi.org/10.5194/hess-25-4319-2021, https://doi.org/10.5194/hess-25-4319-2021, 2021
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This study proposes a multiple-dependence model for estimating streamflow at partially gaged sites. The evaluations are conducted on a case study of the eastern USA and show that the proposed model is suited for infilling missing values. The performance is further evaluated with six other infilling models. Results demonstrate that the proposed model produces more reliable streamflow estimates than the other approaches. The model can be applicable to other hydro-climatological variables.
Xuanxuan Wang, Yaning Chen, Zhi Li, Gonghuan Fang, Fei Wang, and Haichao Hao
Hydrol. Earth Syst. Sci., 25, 3281–3299, https://doi.org/10.5194/hess-25-3281-2021, https://doi.org/10.5194/hess-25-3281-2021, 2021
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The growing water crisis in Central Asia and the complex water politics of the region's transboundary rivers are a hot topic for research, while the dynamic changes of water politics in Central Asia have yet to be studied in depth. Based on the Gini coefficient, water political events and social network analysis, we analyzed the matching degree between water and socio-economic elements and the dynamics of hydropolitics in transboundary river basins of Central Asia.
Jonathan W. Miller, Kimia Karimi, Arumugam Sankarasubramanian, and Daniel R. Obenour
Hydrol. Earth Syst. Sci., 25, 2789–2804, https://doi.org/10.5194/hess-25-2789-2021, https://doi.org/10.5194/hess-25-2789-2021, 2021
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Within a watershed, nutrient export can vary greatly over time and space. In this study, we develop a model to leverage over 30 years of streamflow, precipitation, and nutrient sampling data to characterize nitrogen export from various livestock and land use types across a range of precipitation conditions. Modeling results reveal that urban lands developed before 1980 have remarkably high levels of nitrogen export, while agricultural export is most responsive to precipitation.
Chia-Wen Wu, Frederick N.-F. Chou, and Fong-Zuo Lee
Hydrol. Earth Syst. Sci., 25, 2063–2087, https://doi.org/10.5194/hess-25-2063-2021, https://doi.org/10.5194/hess-25-2063-2021, 2021
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This paper promotes the feasibility of emptying instream storage through joint operation of multiple reservoirs. The trade-off between water supply and emptying reservoir storage and alleviating impacts on downstream environment are thoroughly discussed. Operation of reservoirs is optimized to calibrate the optimal parameters defining the activation and termination of emptying reservoir. The optimized strategy limits the water shortage and maximizes the expected benefits of emptying reservoir.
Cited articles
Abate, E. Y.: Anthropogenic Impacts on Groundwater Resources in the urban Environment of Dire Dawa, Ethiopia. Master Thesis in Geosciences, Department of Geosciences,Faculty of Mathematics and Natural Sciences, University of Oslo, 64 pp., 2010.
Abd El-Salam, M. M. and Abu-Zuid, G. I.: Impact of landfill leachate on the groundwater quality: A case study in Egypt, J. Adv. Res., 2014.
Abdalla, F. A. and Scheytt, T.: Hydrochemistry of surface water and groundwater from a fractured carbonate aquifer in the Helwan area, Egypt. J. Earth Syst. Sci., 121, 109–124, 2012.
Abdel-Lah, A. K. and Shamrukh, M.: Impact of septic system on ground water quality in a Nile valley village, Egypt. Sixth International Water Technology Conference, IWTC 2001, Alexandria, Egypt, 237–245, 2001.
Abdelbaki, C., Asnouni, F., Assoud, I., Cherif, Z. E. A., and Yahiaoui, I.: Contribution to the cartography of the groundwater quality of the urban group of Tlemcen (Algeria), Larhyss J., 16, 7–19, 2013.
Abdellah, A. M., Abdel-Magid, H. M., and Shommo, E. I.: Assessment of Groundwater Quality in Southern Suburb of the Omdurman City of Sudan, Greener J. Environ. Manage. Publ. Safety, 2, 83–90, 2013.
Abdesselam, S., Halitim, A., Jan, A., Trolard, F., and Bourrié, G.: Anthropogenic contamination of groundwater with nitrate in arid region: case study of southern Hodna (Algeria), Environ. Earth Sci., 70, 2129–2141, 2012.
Abenan, A. T., Jean, K. K., Bachir, S. M., Armand, A. K., Serge, D. K., Tanoh, K. J. J., Adiow, E. T., Kouassi, S. H., Jean-Patrice, J., and Jean, B.: Contribution of multicriteria analysis and GIS for the specific vulnerability mapping to agricultural inputs of groundwaters in Bonoua area (Southeast of Côte d'Ivoire), 2012.
Abou, M. M.: Pollution des eaux souterraines en milieu urban, cas de la nappe phréatique de la ville de Niamey, Institut Supérieur des Techniques de l'Eau, 112, 8 pp., 2000.
Ackah, M., Agyemang, O., Anim, A. K., Osei, J., Bentil, N. O., Kpattah, L., Gyamfi, E. T., and Hanson, J. E. K.: Assessment of groundwater quality for drinking and irrigation: the case study of Teiman-Oyarifa Community, Ga East Municipality, Ghana, Proc. Int. Acad. Ecol. Environ. Sci., 1, 186–194, 2011.
Adelekan, B. and Ogunde, O.: Quality of water from dug wells and the lagoon in Lagos Nigeria and associated health risks, Sci. Res. Essay., 7, 1195–1211, 2012.
Affum, A. O., Osae, S. D., Nyarko, B. J., Afful, S., Fianko, J. R., Akiti, T. T., Adomako, D., Acquaah, S. O., Dorleku, M., Antoh, E., Barnes, F., and Affum, E. A.: Total coliforms, arsenic and cadmium exposure through drinking water in the Western Region of Ghana: application of multivariate statistical technique to groundwater quality, Environ. Monit. Assess., 187, 4167, https://doi.org/10.1007/s10661-014-4167-x, 2015.
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Ahmed, A. L. M., Sulaiman, S., Osman, M. M., Saeed, E. M., and Mohamed, Y. A.: Groundwater quality in Khartoum state, Sudan, J. Environ. Hydrol. 8, 7 pp., 2000.
Ahoussi, K. E., Youan, T. M., Loko, S., Adja, M. G., Lasm, T., and Jourda, J. P.: Étude hydrogéochimique des eaux des aquifères de fractures du socle Paléo-protérozoïque du Nord-Est de la Côte d'Ivoire: Cas de la région de Bondoukou, Afrique Sci., 8, 51–68, 2012.
Ake, G. E., Kouadio, H. B., Dongo, K., Dibi, B., Kouame, F. K., and Biemi, J.: Application des méthodes DRASTIC et SI pour l'étude de la vulnérabilité à la pollution par les nitrates (NO3−) de la nappe de Bonoua (Sud-Est dela Côte d'Ivoire), Int. J. Biol. Chem. Sci., 4, 1676–1692, 2010.
Akinbile, C. O.: Environmental Impact of Landfill on Groundwater Quality and Agricultural Soils in Nigeria, Soil Water Res., 7, 18–26, 2012.
Akoteyon, I. S. and Soladoye, O.: Groundwater Quality Assessment in Eti-Osa, Lagos-Nigeria using Multivariate Analysis, J. Appl. Sci. Environ. Manage., 15, 121–125, 2011.
Aladejana, J. A. and Talabi, A. O.: Assessment of Groundwater Quality in Abeokuta Southwestern, Nigeria, Int. J. Eng. Sci., 2, 21–31, 2013.
Alaoui, H. L., Oufdou, K., and Mezrioui, N.: Environmental pollutions impacts on the bacteriological and physicochemical quality of suburban and rural groundwater supplies in Marrakesh area (Morocco), Environ. Monit. Assess., 145, 195–207, 2008.
Aljazzar, T. H.: Adjustment of DRASTIC Vulnerability Index to Assess Groundwater Vulnerability for Nitrate Pollution Using the Advection-Diffusion Cell. Von der Fakultät für Georessourcen und Materialtechnik der Rheinisch-Westfälischen Technischen Hochschule Aachen, 146 pp., 2010.
Aller, L., Bennet, T., Lehr, J. H., and Petty, R. J.: DRASTIC: A standardized system for evaluating groundwater pollution using hydrological settings, Ada, OK, USA: Prepared by the National water Well Association for the US EPA Office of Research and Development, EPA/600/2-85-018, 163 pp., 1985.
Amini, M., Mueller, K., Abbaspour, K. C., Rosenberg, T., Afyuni, M., Møller, K. N., Sarr, M., and Johnson, C. A.: Statistical modeling of global geogenic fluoride contamination in groundwaters, Environ. Sci. Technol., 42, 3662–3668, 2008a.
Amini, M., Abbaspour, K. C., Berg, M., Winkel, L., Hug, S. J.., Hoehn, E., Yang, H., and Johnson, C. A.: Statistical modeling of global geogenic arsenic contamination in groundwater, Environ. Sci. Technol., 42, 3669–3675, 2008b.
Anane, M., Selmi, Y., Limam, A., Jedidi, N., and Jellali, S.: Does irrigation with reclaimed water significantly pollute shallow aquifer with nitrate and salinity? An assay in a perurban area in North Tunisia, Environ. Monit. Assess., 186, 4367–4390, 2014.
Angola Water Works: Annual Drinking Water Quality Report. IN5276001, http://www.angolain.org/Water/documents/Angola2013AnnualWaterReport.pdf (last access: 13 August 2014) 2 pp., 2013.
Ansa-Asare, O. D., Darko, H. F., and Asante, K. A.: Groundwater quality assessment of Akatsi, Adidome and Ho districts in the Volta Region of Ghana, Desalination, 248, 446–452, 2009.
Anthony, K.-O.: Impact of municipal solid wastes on underground water sources in Nigeria, Eur. Sci. J., 8, 19 pp., 2012.
Anuraga, T. S., Ruiz, L., Kumar, M. S. M., Sekhar, M., and Leijnse, A.: Estimating groundwater recharge using land use and soil data: A case study in South India, Agr. Water Manage. 84, 65–76, 2006.
Armah, F. A., Luginaah, I., and Benjamin, A.: Water Quality Index in the Tarkwa Gold Mining Area in Ghana, J. Transdiscipl. Environ. Stud., 11, 15 pp., 2012.
Armah, Y.: Hydrochemical Analysis of Groundwater In The Lower Pra Basin of Ghana, J. Water Resour. Protect., 2, 864–871, 2010.
Ascott, M. J., Wang, L., Stuart, M. E., Ward, R. S., and Hart, A.: Quantification of nitrate storage in the vadose (unsaturated) zone: a missing component of terrestrial N budgets, Hydrol. Process., 542, 694–705, https://doi.org/10.1002/hyp.10748, 2016.
Asslouj, J. E., Kholtei, S., Amrani-Paaza, N. E., and Hilali, A.: Impact des activités anthropiques sur la qualité des eaux souterraines de la communauté Mzamza (Chaouia, Maroc), Rev. Sci. Eau, 20, 309–321, 2007.
Ateawung, J. N.: A GIS-Based Water Balance Study of Africa. Master of Physical Land Resources, Universiteit Gent Vrije Universiteit Brussel Belgium., 55 pp., 2010.
Aza-Gnandji, C. D. R., Xu, Y., Raitt, L., and Levy, J.: Salinity of irrigation water in the Philippi farming area of the Cape Flats, Cape Town, South Africa, Water SA, 39, 199–210, 2013.
Bagalwa, M., Majaliwa, M., Mushagalusa, N., and Karume, K.: Estimation of Transported Pollutant Load from Small Urban Kahuwa River Micro-catchment in Lake Kivu, Democratic Republic of Congo, J. Environ. Sci. Eng., 2, 460–472, 2013.
Bahri, F. and Saibi, H.: Characterization, classification, bacteriological, and evaluation of groundwater from 24 wells in six departments of Algeria, Arab. J. Geosci. 5, 1449–1458, 2012.
Balogun, I. I., Akoteyon, I. S., and Adeaga, O.: Evaluating Land Use Effects on Groundwater Quality in Lagos-Nigeria Using Water Quality Index, J. Sci. Res., 4, 397–409, 2012.
Barhe, T. A. and Bouaka, F.: Physicochemical Characterization and Chlorination of Drilling Water Consumed In Brazzaville-Congo. Journal of Chemical, Biological and Physical Sciences, An International Peer Review E-3, J. Sci., 3, 2328–2336, 2013.
Batisani, N.: Groundwater hydrochemistry evaluation in rural Botswana: A contribution to integrated water resources management, Ethiop. J. Environ. Stud. Manage., (Suppl.1), 5, 521–528, https://doi.org/10.4314/ejesm.v5i4.S12, 2012.
Bauder, J. W., Sinclair, K. N., and Lund, R. E.: Physiographic and land use characteristics associated with nitrate nitrogen-nitrogen in montana groundwater, J. Environ. Qual., 22, 255–262, 1993.
Belghiti, M. L., Chahlaoui, A., Bengoumi, D., and El Moustaine, R.: Etude de la qualite physico-chimique et bacteriologique des eaux souterraines de la nappe plio-quaternaire dans la région de Meknès (Maroc), Larhyss J., 14, 21–36, 2013.
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Short summary
In this paper, we present a meta-analysis of nitrate contamination in groundwater at the pan-African scale. A nitrate data set is constructed based on publications in the web of sciences, and combined with high-resolution generic spatial environmental attributes. A statistical model explains 65 % of the variation of nitrate contamination in groundwater in terms of generic spatial attributes. Nitrate contamination of groundwater at the pan-African scale is mainly affected by population density.
In this paper, we present a meta-analysis of nitrate contamination in groundwater at the...