Articles | Volume 20, issue 6
© Author(s) 2016. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
© 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
Earth and Life Institute, Université catholique de Louvain, Croix du Sud 2, Box 2, B-1348 Louvain-la-Neuve, Belgium
Earth and Life Institute, Université catholique de Louvain, Croix du Sud 2, Box 2, B-1348 Louvain-la-Neuve, Belgium
No articles found.
Damien Delforge, Olivier de Viron, Marnik Vanclooster, Michel Van Camp, and Arnaud Watlet
Hydrol. Earth Syst. Sci., 26, 2181–2199,Short summary
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,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.,
Revised manuscript not acceptedShort summary
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.,
Manuscript not accepted for further reviewShort summary
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.,
Revised manuscript not acceptedShort summary
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,Short summary
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,
H. Sellami, I. La Jeunesse, S. Benabdallah, N. Baghdadi, and M. Vanclooster
Hydrol. Earth Syst. Sci., 18, 2393–2413,
A. P. Tran, M. Vanclooster, and S. Lambot
Hydrol. Earth Syst. Sci., 17, 2543–2556,
J. Minet, N. E. C. Verhoest, S. Lambot, and M. Vanclooster
Hydrol. Earth Syst. Sci. Discuss.,
Revised manuscript has not been submitted
Related subject area
Subject: Water Resources Management | Techniques and Approaches: Modelling approachesDynamically coupling system dynamics and SWAT+ models using Tinamït: application of modular tools for coupled human–water system modelsDevelopment of an integrated socio-hydrological modeling framework for assessing the impacts of shelter location arrangement and human behaviors on flood evacuation processesCooperation in a transboundary river basin: a large-scale socio-hydrological model of the Eastern NileFlexible forecast value metric suitable for a wide range of decisions: application using probabilistic subseasonal streamflow forecastsAn improved model of shade-affected stream temperature in Soil & Water Assessment ToolSeasonal forecasting of snow resources at Alpine sitesOperationalizing equity in multipurpose water systemsEvaluation of a new observationally based channel parameterization for the National Water ModelHigh-resolution drought simulations and comparison to soil moisture observations in GermanyCooperation under conflict: participatory hydrological modeling for science policy dialogues for the Aculeo LakeSocio-hydrological modeling of the tradeoff between flood control and hydropower provided by the Columbia River TreatyChallenges and benefits of quantifying irrigation through the assimilation of Sentinel-1 backscatter observations into Noah-MPQuantifying the trade-offs in re-operating dams for the environment in the Lower Volta RiverA system dynamic model to quantify the impacts of water resources allocation on water–energy–food–society (WEFS) nexusDeveloping a Bayesian network model for understanding river catchment resilience under future change scenariosNet irrigation requirement under different climate scenarios using AquaCrop over EuropeThe role of multi-criteria decision analysis in a transdisciplinary process: co-developing a flood forecasting system in western AfricaUnfolding the relationship between seasonal forecast skill and value in hydropower production: a global analysisDrought impact links to meteorological drought indicators and predictability in SpainOpportunities for seasonal forecasting to support water management outside the tropicsProbabilistic modelling of the inherent field-level pesticide pollution risk in a small drinking water catchment using spatial Bayesian belief networksAre 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 ACEAFuture upstream water consumption and its impact on downstream water availability in the transboundary Indus BasinIdentifying 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 useOptimizing a backscatter forward operator using Sentinel-1 data over irrigated landRobustness of a parsimonious subsurface drainage model at the French national scaleSpatially distributed impacts of climate change and groundwater demand on the water resources in a wadi systemDelineation of dew formation zones in Iran using long-term model simulations and cluster analysisStreamflow estimation at partially gaged sites using multiple-dependence conditions via vine copulasWater resources management and dynamic changes in water politics in the transboundary river basins of Central AsiaAssessing interannual variability in nitrogen sourcing and retention through hybrid Bayesian watershed modelingMinimizing the impact of vacating instream storage of a multi-reservoir system: a trade-off study of water supply and empty flushingGlobal cotton production under climate change – Implications for yield and water consumptionSignatures of human intervention – or not? Downstream intensification of hydrological drought along a large Central Asian river: the individual roles of climate variability and land use changeField-scale soil moisture bridges the spatial-scale gap between drought monitoring and agricultural yieldsSocio-hydrologic modeling of the dynamics of cooperation in the transboundary Lancang–Mekong RiverMulti-level storylines for participatory modeling – involving marginalized communities in Tz'olöj Ya', Mayan GuatemalaBenchmarking an operational hydrological model for providing seasonal forecasts in SwedenImpact of the quality of hydrological forecasts on the management and revenue of hydroelectric reservoirs – a conceptual approachA novel causal structure-based framework for comparing a basin-wide water–energy–food–ecology nexus applied to the data-limited Amu Darya and Syr Darya river basinsProjection of irrigation water demand based on the simulation of synthetic crop coefficients and climate changeComparative analysis of kernel-based versus ANN and deep learning methods in monthly reference evapotranspiration estimationAssessing the value of seasonal hydrological forecasts for improving water resource management: insights from a pilot application in the UKFrom skill to value: isolating the influence of end user behavior on seasonal forecast assessmentThe value of citizen science for flood risk reduction: cost–benefit analysis of a citizen observatory in the Brenta-Bacchiglione catchmentRisk assessment in water resources planning under climate change at the Júcar River basinInterplay of changing irrigation technologies and water reuse: example from the upper Snake River basin, Idaho, USAThe benefit of using an ensemble of seasonal streamflow forecasts in water allocation decisionsEvapotranspiration partition using the multiple energy balance version of the ISBA-A-gs land surface model over two irrigated crops in a semi-arid Mediterranean region (Marrakech, Morocco)
Joel Z. Harms, Julien J. Malard-Adam, Jan F. Adamowski, Ashutosh Sharma, and Albert Nkwasa
Hydrol. Earth Syst. Sci., 27, 1683–1693,Short summary
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,Short summary
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,Short summary
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,Short summary
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,Short summary
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,Short summary
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,Short summary
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,Short summary
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,Short summary
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,Short summary
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,Short summary
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,Short summary
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.
Afua Owusu, Jazmin Zatarain Salazar, Marloes Mul, Pieter van der Zaag, and Jill Slinger
Hydrol. Earth Syst. Sci. Discuss.,
Revised manuscript accepted for HESSShort summary
The construction of two dams in the Lower Volta River, Ghana affected downstream riverine ecosystems and communities. In contrast, Ghana as a whole 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.
Yujie Zeng, Dedi Liu, Shenglian Guo, Lihua Xiong, Pan Liu, Jiabo Yin, and Zhenhui Wu
Hydrol. Earth Syst. Sci., 26, 3965–3988,Short summary
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.
Kerr J. Adams, Christopher A. J. Macleod, Marc J. Metzger, Nicola Melville, Rachel C. Helliwell, Jim Pritchard, and Miriam Glendell
We used participatory methods to create a Bayesian Network (BN) model that 1) mapped complex interactions between human and ecological systems at the catchment scale and 2) measured the impacts of diverse scenarios for future climate, population and land-cover change on the catchment system. Our methods and findings provided stakeholders with a holistic approach for measuring river catchment resilience.
Louise Busschaert, Shannon de Roos, Wim Thiery, Dirk Raes, and Gabriëlle J. M. De Lannoy
Hydrol. Earth Syst. Sci., 26, 3731–3752,Short summary
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,Short summary
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,Short summary
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,Short summary
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,Short summary
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,Short summary
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,Short summary
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,Short summary
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,Short summary
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,Short summary
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,Short summary
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,Short summary
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,Short summary
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,Short summary
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.
Hydrol. Earth Syst. Sci., 25, 4319–4333,Short summary
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,Short summary
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,Short summary
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,Short summary
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.
Yvonne Jans, Werner von Bloh, Sibyll Schaphoff, and Christoph Müller
Hydrol. Earth Syst. Sci., 25, 2027–2044,Short summary
Growth of and irrigation water demand on cotton may be challenged by future climate change. To analyze the global cotton production and irrigation water consumption under spatially varying present and future climatic conditions, we use the global terrestrial biosphere model LPJmL. Our simulation results suggest that the beneficial effects of elevated [CO2] on cotton yields overcompensate yield losses from direct climate change impacts, i.e., without the beneficial effect of [CO2] fertilization.
Artemis Roodari, Markus Hrachowitz, Farzad Hassanpour, and Mostafa Yaghoobzadeh
Hydrol. Earth Syst. Sci., 25, 1943–1967,Short summary
In a combined data analysis and modeling study in the transboundary Helmand River basin, we analyzed spatial patterns of drought and changes therein based on the drought indices as well as on absolute water deficits. Overall the results illustrate that flow deficits and the associated droughts clearly reflect the dynamic interplay between temporally varying regional differences in hydro-meteorological variables together with subtle and temporally varying effects linked to human intervention.
Noemi Vergopolan, Sitian Xiong, Lyndon Estes, Niko Wanders, Nathaniel W. Chaney, Eric F. Wood, Megan Konar, Kelly Caylor, Hylke E. Beck, Nicolas Gatti, Tom Evans, and Justin Sheffield
Hydrol. Earth Syst. Sci., 25, 1827–1847,Short summary
Drought monitoring and yield prediction often rely on coarse-scale hydroclimate data or (infrequent) vegetation indexes that do not always indicate the conditions farmers face in the field. Consequently, decision-making based on these indices can often be disconnected from the farmer reality. Our study focuses on smallholder farming systems in data-sparse developing countries, and it shows how field-scale soil moisture can leverage and improve crop yield prediction and drought impact assessment.
You Lu, Fuqiang Tian, Liying Guo, Iolanda Borzì, Rupesh Patil, Jing Wei, Dengfeng Liu, Yongping Wei, David J. Yu, and Murugesu Sivapalan
Hydrol. Earth Syst. Sci., 25, 1883–1903,Short summary
The upstream countries in the transboundary Lancang–Mekong basin build dams for hydropower, while downstream ones gain irrigation and fishery benefits. Dam operation changes the seasonality of runoff downstream, resulting in their concerns. Upstream countries may cooperate and change their regulations of dams to gain indirect political benefits. The socio-hydrological model couples hydrology, reservoir, economy, and cooperation and reproduces the phenomena, providing a useful model framework.
Jessica A. Bou Nassar, Julien J. Malard, Jan F. Adamowski, Marco Ramírez Ramírez, Wietske Medema, and Héctor Tuy
Hydrol. Earth Syst. Sci., 25, 1283–1306,Short summary
Our research suggests a method that facilitates the inclusion of marginalized stakeholders in model-building activities to address problems in water resources. Our case study showed that knowledge produced by typically excluded stakeholders had significant and unique contributions to the outcome of the process. Moreover, our method facilitated the identification of relationships between societal, economic, and hydrological factors, and it fostered collaborations across different communities.
Marc Girons Lopez, Louise Crochemore, and Ilias G. Pechlivanidis
Hydrol. Earth Syst. Sci., 25, 1189–1209,Short summary
The Swedish hydrological warning service is extending its use of seasonal forecasts, which requires an analysis of the available methods. We evaluate the simple ESP method and find out how and why forecasts vary in time and space. We find that forecasts are useful up to 3 months into the future, especially during winter and in northern Sweden. They tend to be good in slow-reacting catchments and bad in flashy and highly regulated ones. We finally link them with areas of similar behaviour.
Manon Cassagnole, Maria-Helena Ramos, Ioanna Zalachori, Guillaume Thirel, Rémy Garçon, Joël Gailhard, and Thomas Ouillon
Hydrol. Earth Syst. Sci., 25, 1033–1052,
Haiyang Shi, Geping Luo, Hongwei Zheng, Chunbo Chen, Olaf Hellwich, Jie Bai, Tie Liu, Shuang Liu, Jie Xue, Peng Cai, Huili He, Friday Uchenna Ochege, Tim Van de Voorde, and Philippe de Maeyer
Hydrol. Earth Syst. Sci., 25, 901–925,Short summary
Some river basins are considered to be very similar because they have a similar background such as a transboundary, facing threats of human activities. But we still lack understanding of differences under their general similarities. Therefore, we proposed a framework based on a Bayesian network to group watersheds based on similarity levels and compare the causal and systematic differences within the group. We applied it to the Amu and Syr Darya River basin and discussed its universality.
Michel Le Page, Younes Fakir, Lionel Jarlan, Aaron Boone, Brahim Berjamy, Saïd Khabba, and Mehrez Zribi
Hydrol. Earth Syst. Sci., 25, 637–651,Short summary
In the context of major changes, the southern Mediterranean area faces serious challenges with low and continuously decreasing water resources mainly attributed to agricultural use. A method for projecting irrigation water demand under both anthropogenic and climatic changes is proposed. Time series of satellite imagery are used to determine a set of semiempirical equations that can be easily adapted to different future scenarios.
Mohammad Taghi Sattari, Halit Apaydin, Shahab S. Band, Amir Mosavi, and Ramendra Prasad
Hydrol. Earth Syst. Sci., 25, 603–618,Short summary
The aim of study is to estimate the reference evapotranspiration (ET0) amount with artificial intelligence using minimum meteorological parameters in the Corum region, which is an agricultural center of Turkey. Kernel-based GPR and SVR and BFGS-ANN and LSTM models were used to estimate ET0 amounts in 10 different combinations. The results show that all four methods used predicted ET0 amounts at acceptable accuracy and error levels. The BFGS-ANN model showed higher success than the others.
Andres Peñuela, Christopher Hutton, and Francesca Pianosi
Hydrol. Earth Syst. Sci., 24, 6059–6073,Short summary
In this paper we evaluate the potential use of seasonal weather forecasts to improve reservoir operation in a UK water supply system. We found that the use of seasonal forecasts can improve the efficiency of reservoir operation but only if the forecast uncertainty is explicitly considered. We also found the degree of efficiency improvement is strongly affected by the decision maker priorities and the hydrological conditions.
Matteo Giuliani, Louise Crochemore, Ilias Pechlivanidis, and Andrea Castelletti
Hydrol. Earth Syst. Sci., 24, 5891–5902,Short summary
This paper aims at quantifying the value of hydroclimatic forecasts in terms of potential economic benefit to end users in the Lake Como basin (Italy), which allows the inference of a relation between gains in forecast skill and gains in end user profit. We also explore the sensitivity of this benefit to both the forecast system setup and end user behavioral factors, showing that the estimated forecast value is potentially undermined by different levels of end user risk aversion.
Michele Ferri, Uta Wehn, Linda See, Martina Monego, and Steffen Fritz
Hydrol. Earth Syst. Sci., 24, 5781–5798,Short summary
As part of the flood risk management strategy of the Brenta-Bacchiglione catchment (Italy), a citizen observatory for flood risk management is currently being implemented. A cost–benefit analysis of the citizen observatory was undertaken to demonstrate the value of this approach in monetary terms. Results show a reduction in avoided damage of 45 % compared to a scenario without implementation of the citizen observatory. The idea is to promote this methodology for future flood risk management.
Sara Suárez-Almiñana, Abel Solera, Jaime Madrigal, Joaquín Andreu, and Javier Paredes-Arquiola
Hydrol. Earth Syst. Sci., 24, 5297–5315,Short summary
This work responds to the need for an effective methodology that integrates climate change projections into water planning and management to guide complex basin decision-making. This general approach is based on a model chain for management and drought risk assessments and applied to the Júcar River basin (Spain), showing a worrying deterioration of the basin's future water resources availability and drought indicators, despite a considerable uncertainty of results from the mid-century onwards.
Shan Zuidema, Danielle Grogan, Alexander Prusevich, Richard Lammers, Sarah Gilmore, and Paula Williams
Hydrol. Earth Syst. Sci., 24, 5231–5249,Short summary
In our case study we find that increasing the efficiency of irrigation technology will have unintended consequences like reducing water available for aquifer replenishment or for other irrigators. The amount of water needed to stabilize regional aquifers exceeds the amount that could be saved by improving irrigation efficiency. Since users depend upon local groundwater storage, which is more sensitive to management decisions than river flow, comanagement of surface and groundwater is critical.
Alexander Kaune, Faysal Chowdhury, Micha Werner, and James Bennett
Hydrol. Earth Syst. Sci., 24, 3851–3870,Short summary
This paper was developed from PhD research focused on assessing the value of using hydrological datasets in water resource management. Previous studies have assessed how well data can help in predicting river flows, but there is a lack of knowledge of how well data can help in water allocation decisions. In our research, it was found that using seasonal streamflow forecasts improves the available water estimates, resulting in better water allocation decisions in a highly regulated basin.
Ghizlane Aouade, Lionel Jarlan, Jamal Ezzahar, Salah Er-Raki, Adrien Napoly, Abdelfattah Benkaddour, Said Khabba, Gilles Boulet, Sébastien Garrigues, Abdelghani Chehbouni, and Aaron Boone
Hydrol. Earth Syst. Sci., 24, 3789–3814,Short summary
Our objective is to question the representation of the energy budget in surface–vegetation–atmosphere transfer models for the prediction of the convective fluxes in crops with complex structures (row) and under transient hydric regimes due to irrigation. The main result is that a coupled multiple energy balance approach is necessary to properly predict surface exchanges for these complex crops. It also points out the need for other similar studies on various crops with different sparsity levels.
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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...