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.
Research article
| 
17 Jun 2016
Research article |
| 17 Jun 2016
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.
François Toussaint, Alice Alonso, and Marnik Vanclooster
EGUsphere, https://doi.org/10.5194/egusphere-2025-1326, https://doi.org/10.5194/egusphere-2025-1326, 2025
This preprint is open for discussion and under review for Hydrology and Earth System Sciences (HESS).
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We analysed 20 years of satellite data to study changes in surface phytoplankton concentration in Lake Tanganyika. Results reveal strong seasonal patterns linked to known hydrodynamics, with decreasing levels in deep areas and increases in shallow regions. These changes could alter the lake’s ecosystem and threaten the resources that millions of people rely on.
Elise Verstraeten, Alice Alonso, Louise Collier, and Marnik Vanclooster
Hydrol. Earth Syst. Sci., 29, 1829–1845, https://doi.org/10.5194/hess-29-1829-2025, https://doi.org/10.5194/hess-29-1829-2025, 2025
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This study takes a data-driven approach to evaluate long-term groundwater nitrate concentration trends in Wallonia, Belgium, over ~20 years following the implementation of regional nitrogen management policies. Results highlight a persistently negative impact of agricultural land use, the importance of sustained policies and long-term monitoring to mitigate nitrogen legacy effects, and the need for improved datasets to better capture controlling factors.
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
Short summary
Short summary
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
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The H2Ours game to explore water use, resources and sustainability: connecting issues in two landscapes in Indonesia
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Development of an integrated socio-hydrological modeling framework for assessing the impacts of shelter location arrangement and human behaviors on flood evacuation processes
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Atabek Umirbekov, Mayra Daniela Peña-Guerrero, Iulii Didovets, Heiko Apel, Abror Gafurov, and Daniel Müller
Hydrol. Earth Syst. Sci., 29, 3055–3071, https://doi.org/10.5194/hess-29-3055-2025, https://doi.org/10.5194/hess-29-3055-2025, 2025
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Seasonal streamflow forecasts for snowmelt-dominated catchments often rely on snowpack data, which are not always available and are prone to errors. Our study evaluates near-real-time global snow estimates and climate oscillation indices for predictions in the data-scarce mountains of central Asia. We show that climate indices can improve prediction accuracy at longer lead times, help offset snow data uncertainty, and enhance predictions where streamflow depends on in-season climate variability.
Lauren McGiven, Kinsey Poland, Caleb Reinking, and Marc F. Müller
Hydrol. Earth Syst. Sci., 29, 2961–2974, https://doi.org/10.5194/hess-29-2961-2025, https://doi.org/10.5194/hess-29-2961-2025, 2025
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Thirsty Earth is an educational game where students are farmers making water decisions amid climate uncertainty, common-pool costs, and resource constraints. The game is web-based and adapted for remote learning either as a light Google Sheets version or as a fully interactive graphical interface. It bridges technical water management and governance concepts from the social sciences, providing experiential interdisciplinary learning that traditional science and engineering curricula often overlook.
Sarah Quỳnh-Giang Ho and Uwe Ehret
Hydrol. Earth Syst. Sci., 29, 2785–2810, https://doi.org/10.5194/hess-29-2785-2025, https://doi.org/10.5194/hess-29-2785-2025, 2025
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In this paper, we use models to demonstrate that even small flood reservoirs – which capture water to avoid floods downstream – can be repurposed to release water in drier conditions without affecting their ability to protect against floods. By capturing water and releasing it once levels are low, we show that reservoirs can greatly increase the water available in drought. Having more water available to the reservoir, however, is not necessarily better for drought protection.
Mengxiang Zhang and Ting Fong May Chui
Hydrol. Earth Syst. Sci., 29, 2655–2695, https://doi.org/10.5194/hess-29-2655-2025, https://doi.org/10.5194/hess-29-2655-2025, 2025
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This study introduces a multiagent socio-hydrologic framework for city-, inter-city-, and watershed-scale integrated green infrastructures (GIs) and water resource management. Applied to the Upper Mississippi River basin, it explores GI-driven water-sharing dynamics in a watershed. It identifies four city-scale water use patterns and characterizes cost and equity on broader scales, thereby enhancing comprehension of the role of GIs in water resource management and aiding decision-making.
Roland Baatz, Patrick Davies, Paolo Nasta, and Heye Bogena
Hydrol. Earth Syst. Sci., 29, 2583–2597, https://doi.org/10.5194/hess-29-2583-2025, https://doi.org/10.5194/hess-29-2583-2025, 2025
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The data-driven approach enhances soil water content measurements by improving the precision of cosmic ray neutron sensors (CRNSs). This study demonstrates a new method to account for dynamics in air pressure, atmospheric humidity, and incoming neutron intensity. Soil water content measured by CRNSs showed reduced errors compared to reference measurements. The findings highlight the need for precise adjustments to better measure soil moisture for agricultural, water, and climate monitoring.
Malve Heinz, Maria Eliza Turek, Bettina Schaefli, Andreas Keiser, and Annelie Holzkämper
Hydrol. Earth Syst. Sci., 29, 1807–1827, https://doi.org/10.5194/hess-29-1807-2025, https://doi.org/10.5194/hess-29-1807-2025, 2025
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Potato farmers in Switzerland are facing drier conditions and water restrictions. We explored how improving soil health and planting early-maturing potato varieties might help them to adapt. Using a computer model, we simulated potato yields and irrigation water needs under water scarcity. Our results show that earlier-maturing potato varieties reduce the reliance on irrigation but result in lower yields. However, improving soil health can significantly reduce yield losses.
Maliko Tanguy, Michael Eastman, Amulya Chevuturi, Eugene Magee, Elizabeth Cooper, Robert H. B. Johnson, Katie Facer-Childs, and Jamie Hannaford
Hydrol. Earth Syst. Sci., 29, 1587–1614, https://doi.org/10.5194/hess-29-1587-2025, https://doi.org/10.5194/hess-29-1587-2025, 2025
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Our research compares two techniques, bias correction (BC) and data assimilation (DA), for improving river flow forecasts across 316 UK catchments. BC, which corrects errors after simulation, showed broad improvements, while DA, adjusting model states before forecast, excelled under specific conditions like snowmelt and high baseflows. Each method's unique strengths suit different scenarios. These insights can enhance forecasting systems, offering reliable and user-friendly hydrological predictions.
Yongshin Lee, Andres Peñuela, Francesca Pianosi, and Miguel Angel Rico-Ramirez
Hydrol. Earth Syst. Sci., 29, 1429–1447, https://doi.org/10.5194/hess-29-1429-2025, https://doi.org/10.5194/hess-29-1429-2025, 2025
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This study assesses the value of seasonal flow forecasts (SFFs) in informing decision-making for drought management in South Korea and introduces a novel method for assessing values benchmarked against historical operations. Our results showed the importance of considering flow forecast uncertainty in reservoir operations. There was no significant correlation between the forecast accuracy and value. The method for selecting a compromise release schedule was a key control of the value.
Mari R. Tye, Ming Ge, Jadwiga H. Richter, Ethan D. Gutmann, Allyson Rugg, Cindy L. Bruyère, Sue Ellen Haupt, Flavio Lehner, Rachel McCrary, Andrew J. Newman, and Andy Wood
Hydrol. Earth Syst. Sci., 29, 1117–1133, https://doi.org/10.5194/hess-29-1117-2025, https://doi.org/10.5194/hess-29-1117-2025, 2025
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There is a perceived mismatch between the spatial scales on which global climate models can produce data and those needed for water management decisions. However, poor communication of specific metrics relevant to local decisions is also a problem. We assessed the credibility of a set of water management decision metrics in the Community Earth System Model v2 (CESM2). CESM2 shows potentially greater use of its output in long-range water management decisions.
Shengnan Fu, David M. Schultz, Heng Lyu, Zhonghua Zheng, and Chi Zhang
Hydrol. Earth Syst. Sci., 29, 767–783, https://doi.org/10.5194/hess-29-767-2025, https://doi.org/10.5194/hess-29-767-2025, 2025
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We create China’s first open county-level urban flood dataset (2000–2022) using news media data with the help of deep learning. The dataset reflects both natural and societal influences and includes 7595 urban flood events across 2051 counties, covering 46 % of China’s land area. It reveals the predominance of summer floods, an upward trend since 2000, and a decline from southeast to northwest. Notably, some highly developed regions show a decrease, likely due to improved flood management.
Saifhon Tomkratoke, Siriwat Kongkulsiri, Pornampai Narenpitak, and Sirod Sirisup
EGUsphere, https://doi.org/10.5194/egusphere-2024-4052, https://doi.org/10.5194/egusphere-2024-4052, 2025
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Our research examines saltwater intrusion variability in the Lower Chao Phraya River, Thailand, focusing on key drivers like drought and sea-level fluctuations. By identifying patterns of dependence and independence, we assess fundamental drivers and develop a robust numerical model. The model validates our findings, highlights local factors, and proposes effective mitigation strategies. These insights are valuable for hydrology and environmental management communities.
Weibin Zhang, Xining Zhao, Xuerui Gao, Wei Liang, Junyi Li, and Baoqing Zhang
Hydrol. Earth Syst. Sci., 29, 507–524, https://doi.org/10.5194/hess-29-507-2025, https://doi.org/10.5194/hess-29-507-2025, 2025
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The Yellow River basin shows worsening water stress indicators (WSIs) over 1965‒2020. Water withdrawal is the main factor driving WSI before 2000, balanced by water availability. Local water yield and upstream flows are key drivers of sub-basin water availability. Water demand is expected to rise by 6.5 % in the 2030s, creating an 8.36 km³ surface water deficit. Enhanced irrigation efficiency can cut this deficit by 25 %, maintaining the stress level but worsening it for 44.9% of the population.
Benjamin D. West, Reed M. Maxwell, and Laura E. Condon
Hydrol. Earth Syst. Sci., 29, 245–259, https://doi.org/10.5194/hess-29-245-2025, https://doi.org/10.5194/hess-29-245-2025, 2025
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This article describes the addition of reservoirs to the hydrologic model ParFlow. ParFlow is particularly good at helping us understand some of the broader drivers behind different parts of the water cycle. By having reservoirs in such a model, we hope to be able to better understand both our impacts on the environment and how to adjust our management of reservoirs to changing conditions.
Shan Sang, Yan Li, Chengcheng Hou, Shuangshuang Zi, and Huiqing Lin
Hydrol. Earth Syst. Sci., 29, 67–84, https://doi.org/10.5194/hess-29-67-2025, https://doi.org/10.5194/hess-29-67-2025, 2025
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Green water exchanges between each province in China form an interconnected flow network and have substantial socioeconomic values. Green water flow and its teleconnected socioeconomic effects should be considered in water resource management in addition to blue water.
Jiaoyang Wang, Dedi Liu, Shenglian Guo, Lihua Xiong, Pan Liu, Hua Chen, Jie Chen, Jiabo Yin, and Yuling Zhang
Hydrol. Earth Syst. Sci. Discuss., https://doi.org/10.5194/hess-2024-399, https://doi.org/10.5194/hess-2024-399, 2025
Revised manuscript accepted for HESS
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The unclear feedback loops of water supply-hydropower generation-environmental conservation (SHE) nexus with inter-basin water diversion projects (IWDPs) increase the uncertainty in the rational scheduling of water resources for the water receiving and water donation areas. To address the different impacts of IWDPs on the dynamic SHE nexus and explore collaborative states, a framework was proposed to identify these impacts across the multiple temporal and spatial scales in a reservoirs group.
Laure Baratgin, Jan Polcher, Patrice Dumas, and Philippe Quirion
Hydrol. Earth Syst. Sci., 28, 5479–5509, https://doi.org/10.5194/hess-28-5479-2024, https://doi.org/10.5194/hess-28-5479-2024, 2024
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Hydrological modeling is valuable for estimating the potential impact of climate change on hydropower generation. This study presents a comprehensive approach to modeling the management of hydroelectric reservoirs in hydrological models. The total power grid demand for hydropower is distributed to the various power plants to compute their release. The method is tested on the French national power grid, and it is demonstrated that it successfully reproduces the observed behavior of reservoirs.
Ziyue Yin, Jian Song, Dianguang Liu, Jianfeng Wu, Yun Yang, Yuanyuan Sun, and Jichun Wu
Hydrol. Earth Syst. Sci. Discuss., https://doi.org/10.5194/hess-2024-387, https://doi.org/10.5194/hess-2024-387, 2024
Revised manuscript accepted for HESS
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Mining activities threaten aquatic ecosystems, soil ecosystems, and human health worldwide. This study established a high-quality database and a national 0.5° gridded dataset to reveal the status and spatial pattern of mining-affected water pollution, human health risks, and their potential multifaceted challenges. It provides in-depth insights to guide policymakers in designing differentiated management strategies for the sustainable development of mines.
Ruikang Zhang, Dedi Liu, Lihua Xiong, Jie Chen, Hua Chen, and Jiabo Yin
Hydrol. Earth Syst. Sci., 28, 5229–5247, https://doi.org/10.5194/hess-28-5229-2024, https://doi.org/10.5194/hess-28-5229-2024, 2024
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Flash flood warnings cannot be effective without people’s responses to them. We propose a method to determine the threshold of issuing warnings based on a people’s response process simulation. The results show that adjusting the warning threshold according to people’s tolerance levels to the failed warnings can improve warning effectiveness, but the prerequisite is to increase forecasting accuracy and decrease forecasting variance.
Mohsen Amini Fasakhodi, Hakan Djuma, Ioannis Sofokleous, Marinos Eliades, and Adriana Bruggeman
Hydrol. Earth Syst. Sci., 28, 5209–5227, https://doi.org/10.5194/hess-28-5209-2024, https://doi.org/10.5194/hess-28-5209-2024, 2024
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This study examined the water use of pine and cypress trees in a semiarid Mediterranean forest environment. We applied a widely used land surface model (Noah-MP) to simulate the water balance of the ecosystem. We found good modeling results for soil moisture. However, the model underestimated the transpiration of the trees during the dry summer months. These findings indicate that more research is needed to improve the modeling of ecosystem responses to climate and land use change.
Manuel Quintanilla-Albornoz, Xavier Miarnau, Ana Pelechá, Héctor Nieto, and Joaquim Bellvert
Hydrol. Earth Syst. Sci., 28, 4797–4818, https://doi.org/10.5194/hess-28-4797-2024, https://doi.org/10.5194/hess-28-4797-2024, 2024
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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.
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., 28, 4157–4186, https://doi.org/10.5194/hess-28-4157-2024, https://doi.org/10.5194/hess-28-4157-2024, 2024
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The exact power of models often remains hidden, especially when neutrality is claimed. Our review of 61 scientific articles shows that in the scientific literature little attention is given to the power of water models to influence development processes and outcomes. However, 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 are made and with what effects.
Saskia Salwey, Gemma Coxon, Francesca Pianosi, Rosanna Lane, Chris Hutton, Michael Bliss Singer, Hilary McMillan, and Jim Freer
Hydrol. Earth Syst. Sci., 28, 4203–4218, https://doi.org/10.5194/hess-28-4203-2024, https://doi.org/10.5194/hess-28-4203-2024, 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 and 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.
Amelie Herzog, Jost Hellwig, and Kerstin Stahl
Hydrol. Earth Syst. Sci., 28, 4065–4083, https://doi.org/10.5194/hess-28-4065-2024, https://doi.org/10.5194/hess-28-4065-2024, 2024
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Surface water–groundwater interaction can vary along a river. This study used a groundwater model that reproduced relative observed longitudinal and vertical connectivity patterns in the river network to assess the system's response to imposed stress tests. For the case study, imposed groundwater abstraction appears to influence connectivity relatively more than altered recharge, but a quantification of absolute exchange flows will require further model improvements.
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.
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.
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.
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.
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.
Aghzar, N., Berdai, H., Bellouti, A., and Soudi, B.: Pollution nitrique des eaux souterraines au Tadla (Maroc), J. Water Sci., 15, 459–492, 2002.
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.
Belkhiri, L. and Mouni, L.: Hydrochemical analysis and evaluation of groundwater quality in El Eulma area, Algeria, Appl. Water Sci., 2, 127–133, 2012.
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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...
