Articles | Volume 22, issue 9
https://doi.org/10.5194/hess-22-4981-2018
© Author(s) 2018. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/hess-22-4981-2018
© Author(s) 2018. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
27 Sep 2018
Research article |
| 27 Sep 2018
| 27 Sep 2018
Assessment of hydrological pathways in East African montane catchments under different land use
Suzanne R. Jacobs
CORRESPONDING AUTHOR
Centre for International Development and Environmental Research (ZEU),
Justus Liebig University, Senckenbergstr. 3, 35390 Giessen, Germany
Institute for Landscape Ecology and Resources Management (ILR), Justus
Liebig University, Heinrich-Buff-Ring 26, 35392 Giessen, Germany
Karlsruhe Institute of Technology, Institute of Meteorology and
Climate Research, Atmospheric Environmental Research (KIT/IMK-IFU),
Kreuzeckbahnstr. 19, 82467 Garmisch-Partenkirchen, Germany
Centre for International Forestry Research (CIFOR), c/o World
Agroforestry Centre, United Nations Avenue, Gigiri, P.O. Box 30677, 00100
Nairobi, Kenya
Edison Timbe
Facultad de Ciencias Agropecuarias, Carrera de Ingeniería
Agronómica, Universidad de Cuenca, Cuenca 010111, Ecuador
Björn Weeser
Centre for International Development and Environmental Research (ZEU),
Justus Liebig University, Senckenbergstr. 3, 35390 Giessen, Germany
Institute for Landscape Ecology and Resources Management (ILR), Justus
Liebig University, Heinrich-Buff-Ring 26, 35392 Giessen, Germany
Mariana C. Rufino
Centre for International Forestry Research (CIFOR), c/o World
Agroforestry Centre, United Nations Avenue, Gigiri, P.O. Box 30677, 00100
Nairobi, Kenya
Lancaster Environment Centre, Lancaster University, Lancaster LA1 4YQ,
UK
Klaus Butterbach-Bahl
Karlsruhe Institute of Technology, Institute of Meteorology and
Climate Research, Atmospheric Environmental Research (KIT/IMK-IFU),
Kreuzeckbahnstr. 19, 82467 Garmisch-Partenkirchen, Germany
Mazingira Centre, International Livestock Research Institute (ILRI),
P.O. Box 30709, 00100 Nairobi, Kenya
Lutz Breuer
Centre for International Development and Environmental Research (ZEU),
Justus Liebig University, Senckenbergstr. 3, 35390 Giessen, Germany
Institute for Landscape Ecology and Resources Management (ILR), Justus
Liebig University, Heinrich-Buff-Ring 26, 35392 Giessen, Germany
Related authors
Jaqueline Stenfert Kroese, John N. Quinton, Suzanne R. Jacobs, Lutz Breuer, and Mariana C. Rufino
SOIL, 7, 53–70, https://doi.org/10.5194/soil-7-53-2021, https://doi.org/10.5194/soil-7-53-2021, 2021
Short summary
Short summary
Particulate macronutrient concentrations were up to 3-fold higher in a natural forest catchment compared to fertilized agricultural catchments. Although the particulate macronutrient concentrations were lower in the smallholder agriculture catchment, because of higher sediment loads from that catchment, the total particulate macronutrient loads were higher. Land management practices should be focused on agricultural land to reduce the loss of soil carbon and nutrients to the stream.
Roxanne Daelman, Marijn Bauters, Matti Barthel, Emmanuel Bulonza, Lodewijk Lefevre, José Mbifo, Johan Six, Klaus Butterbach-Bahl, Benjamin Wolf, Ralf Kiese, and Pascal Boeckx
Biogeosciences, 22, 1529–1542, https://doi.org/10.5194/bg-22-1529-2025, https://doi.org/10.5194/bg-22-1529-2025, 2025
Short summary
Short summary
The increase in atmospheric concentrations of several greenhouse gases (GHGs) since 1750 is attributed to human activity. However, natural ecosystems, such as tropical forests, also contribute to GHG budgets. The Congo Basin hosts the second largest tropical forest and is understudied. In this study, measurements of soil GHG exchange were carried out during 16 months in a tropical forest in the Congo Basin. Overall, the soil acted as a major source of CO2 and N2O and a minor sink of CH4.
Max Weißenborn, Lutz Breuer, and Tobias Houska
Hydrol. Earth Syst. Sci. Discuss., https://doi.org/10.5194/hess-2024-183, https://doi.org/10.5194/hess-2024-183, 2024
Revised manuscript under review for HESS
Short summary
Short summary
Our study compares neural network models for predicting discharge in ungauged basins. We evaluated Convolutional Neural Networks (CNN), Long Short-Term Memory (LSTM) and Gated Recurrent Units (GRU) using 28 years of weather data. CNN showed the best accuracy, while GRU were faster and nearly as accurate. Adding static features improved all models. The research enhances flood forecasting and water management in regions lacking direct measurements, offering efficient and accurate predictive tools.
Odysseas Sifounakis, Edwin Haas, Klaus Butterbach-Bahl, and Maria P. Papadopoulou
Biogeosciences, 21, 1563–1581, https://doi.org/10.5194/bg-21-1563-2024, https://doi.org/10.5194/bg-21-1563-2024, 2024
Short summary
Short summary
We performed a full assessment of the carbon and nitrogen cycles of a cropland ecosystem. An uncertainty analysis and quantification of all carbon and nitrogen fluxes were deployed. The inventory simulations include greenhouse gas emissions of N2O, NH3 volatilization and NO3 leaching from arable land cultivation in Greece. The inventory also reports changes in soil organic carbon and nitrogen stocks in arable soils.
Elizabeth Gachibu Wangari, Ricky Mwangada Mwanake, Tobias Houska, David Kraus, Gretchen Maria Gettel, Ralf Kiese, Lutz Breuer, and Klaus Butterbach-Bahl
Biogeosciences, 20, 5029–5067, https://doi.org/10.5194/bg-20-5029-2023, https://doi.org/10.5194/bg-20-5029-2023, 2023
Short summary
Short summary
Agricultural landscapes act as sinks or sources of the greenhouse gases (GHGs) CO2, CH4, or N2O. Various physicochemical and biological processes control the fluxes of these GHGs between ecosystems and the atmosphere. Therefore, fluxes depend on environmental conditions such as soil moisture, soil temperature, or soil parameters, which result in large spatial and temporal variations of GHG fluxes. Here, we describe an example of how this variation may be studied and analyzed.
Ricky Mwangada Mwanake, Gretchen Maria Gettel, Elizabeth Gachibu Wangari, Clarissa Glaser, Tobias Houska, Lutz Breuer, Klaus Butterbach-Bahl, and Ralf Kiese
Biogeosciences, 20, 3395–3422, https://doi.org/10.5194/bg-20-3395-2023, https://doi.org/10.5194/bg-20-3395-2023, 2023
Short summary
Short summary
Despite occupying <1 %; of the globe, streams are significant sources of greenhouse gas (GHG) emissions. In this study, we determined anthropogenic effects on GHG emissions from streams. We found that anthropogenic-influenced streams had up to 20 times more annual GHG emissions than natural ones and were also responsible for seasonal peaks. Anthropogenic influences also altered declining GHG flux trends with stream size, with potential impacts on stream-size-based spatial upscaling techniques.
Joseph Okello, Marijn Bauters, Hans Verbeeck, Samuel Bodé, John Kasenene, Astrid Françoys, Till Engelhardt, Klaus Butterbach-Bahl, Ralf Kiese, and Pascal Boeckx
Biogeosciences, 20, 719–735, https://doi.org/10.5194/bg-20-719-2023, https://doi.org/10.5194/bg-20-719-2023, 2023
Short summary
Short summary
The increase in global and regional temperatures has the potential to drive accelerated soil organic carbon losses in tropical forests. We simulated climate warming by translocating intact soil cores from higher to lower elevations. The results revealed increasing temperature sensitivity and decreasing losses of soil organic carbon with increasing elevation. Our results suggest that climate warming may trigger enhanced losses of soil organic carbon from tropical montane forests.
Jaber Rahimi, Expedit Evariste Ago, Augustine Ayantunde, Sina Berger, Jan Bogaert, Klaus Butterbach-Bahl, Bernard Cappelaere, Jean-Martial Cohard, Jérôme Demarty, Abdoul Aziz Diouf, Ulrike Falk, Edwin Haas, Pierre Hiernaux, David Kraus, Olivier Roupsard, Clemens Scheer, Amit Kumar Srivastava, Torbern Tagesson, and Rüdiger Grote
Geosci. Model Dev., 14, 3789–3812, https://doi.org/10.5194/gmd-14-3789-2021, https://doi.org/10.5194/gmd-14-3789-2021, 2021
Short summary
Short summary
West African Sahelian and Sudanian ecosystems are important regions for global carbon exchange, and they provide valuable food and fodder resources. Therefore, we simulated net ecosystem exchange and aboveground biomass of typical ecosystems in this region with an improved process-based biogeochemical model, LandscapeDNDC. Carbon stocks and exchange rates were particularly correlated with the abundance of trees. Grass and crop yields increased under humid climatic conditions.
Jaqueline Stenfert Kroese, John N. Quinton, Suzanne R. Jacobs, Lutz Breuer, and Mariana C. Rufino
SOIL, 7, 53–70, https://doi.org/10.5194/soil-7-53-2021, https://doi.org/10.5194/soil-7-53-2021, 2021
Short summary
Short summary
Particulate macronutrient concentrations were up to 3-fold higher in a natural forest catchment compared to fertilized agricultural catchments. Although the particulate macronutrient concentrations were lower in the smallholder agriculture catchment, because of higher sediment loads from that catchment, the total particulate macronutrient loads were higher. Land management practices should be focused on agricultural land to reduce the loss of soil carbon and nutrients to the stream.
Amani Mahindawansha, Christoph Külls, Philipp Kraft, and Lutz Breuer
Hydrol. Earth Syst. Sci., 24, 3627–3642, https://doi.org/10.5194/hess-24-3627-2020, https://doi.org/10.5194/hess-24-3627-2020, 2020
Short summary
Short summary
Stable isotopes of soil water are an effective tool to reveal soil hydrological processes in irrigated agricultural fields. Flow mechanisms and isotopic patterns of soil water in the soil matrix differ, depending on the crop and irrigation practices. Isotope data supported the fact that unproductive water losses via evaporation can be reduced by introducing dry seasonal crops to the crop rotation system.
Michael C. Thrun, Alfred Ultsch, and Lutz Breuer
Geosci. Model Dev. Discuss., https://doi.org/10.5194/gmd-2020-87, https://doi.org/10.5194/gmd-2020-87, 2020
Revised manuscript not accepted
Short summary
Short summary
We propose an explainable AI (XAI) framework for times series describing water quality & environmental parameters. The relationship between parameters is investigated by swarm based cluster analysis designed to find similar days within & dissimilar days between clusters. Resulting clusters define three states of water bodies & are visualized by a topographic map of high-dimensional structures. Rules generated by the XAI system explain clusters & improve the understanding of aquatic environments.
Chris R. Flechard, Andreas Ibrom, Ute M. Skiba, Wim de Vries, Marcel van Oijen, David R. Cameron, Nancy B. Dise, Janne F. J. Korhonen, Nina Buchmann, Arnaud Legout, David Simpson, Maria J. Sanz, Marc Aubinet, Denis Loustau, Leonardo Montagnani, Johan Neirynck, Ivan A. Janssens, Mari Pihlatie, Ralf Kiese, Jan Siemens, André-Jean Francez, Jürgen Augustin, Andrej Varlagin, Janusz Olejnik, Radosław Juszczak, Mika Aurela, Daniel Berveiller, Bogdan H. Chojnicki, Ulrich Dämmgen, Nicolas Delpierre, Vesna Djuricic, Julia Drewer, Eric Dufrêne, Werner Eugster, Yannick Fauvel, David Fowler, Arnoud Frumau, André Granier, Patrick Gross, Yannick Hamon, Carole Helfter, Arjan Hensen, László Horváth, Barbara Kitzler, Bart Kruijt, Werner L. Kutsch, Raquel Lobo-do-Vale, Annalea Lohila, Bernard Longdoz, Michal V. Marek, Giorgio Matteucci, Marta Mitosinkova, Virginie Moreaux, Albrecht Neftel, Jean-Marc Ourcival, Kim Pilegaard, Gabriel Pita, Francisco Sanz, Jan K. Schjoerring, Maria-Teresa Sebastià, Y. Sim Tang, Hilde Uggerud, Marek Urbaniak, Netty van Dijk, Timo Vesala, Sonja Vidic, Caroline Vincke, Tamás Weidinger, Sophie Zechmeister-Boltenstern, Klaus Butterbach-Bahl, Eiko Nemitz, and Mark A. Sutton
Biogeosciences, 17, 1583–1620, https://doi.org/10.5194/bg-17-1583-2020, https://doi.org/10.5194/bg-17-1583-2020, 2020
Short summary
Short summary
Experimental evidence from a network of 40 monitoring sites in Europe suggests that atmospheric nitrogen deposition to forests and other semi-natural vegetation impacts the carbon sequestration rates in ecosystems, as well as the net greenhouse gas balance including other greenhouse gases such as nitrous oxide and methane. Excess nitrogen deposition in polluted areas also leads to other environmental impacts such as nitrogen leaching to groundwater and other pollutant gaseous emissions.
Chris R. Flechard, Marcel van Oijen, David R. Cameron, Wim de Vries, Andreas Ibrom, Nina Buchmann, Nancy B. Dise, Ivan A. Janssens, Johan Neirynck, Leonardo Montagnani, Andrej Varlagin, Denis Loustau, Arnaud Legout, Klaudia Ziemblińska, Marc Aubinet, Mika Aurela, Bogdan H. Chojnicki, Julia Drewer, Werner Eugster, André-Jean Francez, Radosław Juszczak, Barbara Kitzler, Werner L. Kutsch, Annalea Lohila, Bernard Longdoz, Giorgio Matteucci, Virginie Moreaux, Albrecht Neftel, Janusz Olejnik, Maria J. Sanz, Jan Siemens, Timo Vesala, Caroline Vincke, Eiko Nemitz, Sophie Zechmeister-Boltenstern, Klaus Butterbach-Bahl, Ute M. Skiba, and Mark A. Sutton
Biogeosciences, 17, 1621–1654, https://doi.org/10.5194/bg-17-1621-2020, https://doi.org/10.5194/bg-17-1621-2020, 2020
Short summary
Short summary
Nitrogen deposition from the atmosphere to unfertilized terrestrial vegetation such as forests can increase carbon dioxide uptake and favour carbon sequestration by ecosystems. However the data from observational networks are difficult to interpret in terms of a carbon-to-nitrogen response, because there are a number of other confounding factors, such as climate, soil physical properties and fertility, and forest age. We propose a model-based method to untangle the different influences.
Florian U. Jehn, Konrad Bestian, Lutz Breuer, Philipp Kraft, and Tobias Houska
Hydrol. Earth Syst. Sci., 24, 1081–1100, https://doi.org/10.5194/hess-24-1081-2020, https://doi.org/10.5194/hess-24-1081-2020, 2020
Short summary
Short summary
We grouped 643 rivers from the United States into 10 behavioral groups based on their hydrological behavior (e.g., how much water they transport overall). Those groups are aligned with the ecoregions in the United States. Depending on the groups’ location and other characteristics, either snow, aridity or seasonality is most important for the behavior of the rivers in a group. We also find that very similar river behavior can be found in rivers far apart and with different characteristics.
Sebastian Multsch, Maarten S. Krol, Markus Pahlow, André L. C. Assunção, Alberto G. O. P. Barretto, Quirijn de Jong van Lier, and Lutz Breuer
Hydrol. Earth Syst. Sci., 24, 307–324, https://doi.org/10.5194/hess-24-307-2020, https://doi.org/10.5194/hess-24-307-2020, 2020
Short summary
Short summary
Expanding irrigation in agriculture is one of Brazil's strategies to increase production. In this study the amount of water required to grow the main crops has been calculated and compared to the water that is available in rivers at least 95 % of the time. Future decisions regarding expanding irrigated cropping areas must, while intensifying production practices, consider the likely regional effects on water scarcity levels, in order to reach sustainable agricultural production.
Erkan Ibraim, Benjamin Wolf, Eliza Harris, Rainer Gasche, Jing Wei, Longfei Yu, Ralf Kiese, Sarah Eggleston, Klaus Butterbach-Bahl, Matthias Zeeman, Béla Tuzson, Lukas Emmenegger, Johan Six, Stephan Henne, and Joachim Mohn
Biogeosciences, 16, 3247–3266, https://doi.org/10.5194/bg-16-3247-2019, https://doi.org/10.5194/bg-16-3247-2019, 2019
Short summary
Short summary
Nitrous oxide (N2O) is an important greenhouse gas and the major stratospheric ozone-depleting substance; therefore, mitigation of anthropogenic N2O emissions is needed. To trace N2O-emitting source processes, in this study, we observed N2O isotopocules above an intensively managed grassland research site with a recently developed laser spectroscopy method. Our results indicate that the domain of denitrification or nitrifier denitrification was the major N2O source.
Florian U. Jehn, Lutz Breuer, Tobias Houska, Konrad Bestian, and Philipp Kraft
Hydrol. Earth Syst. Sci., 22, 4565–4581, https://doi.org/10.5194/hess-22-4565-2018, https://doi.org/10.5194/hess-22-4565-2018, 2018
Short summary
Short summary
By realizing that hydrological models are not one single hypothesis, but an assemblage of many hypotheses, new ways to scrutinize hydrological models are needed. Up until now, studies concentrate on comparing existing models or built models incrementally. This approach here tries to tackle the problem the other way around. We construct a complex model, containing all processes important for the catchment, and deconstruct it step by step to understand the influence of single processes.
Natalie Orlowski, Lutz Breuer, Nicolas Angeli, Pascal Boeckx, Christophe Brumbt, Craig S. Cook, Maren Dubbert, Jens Dyckmans, Barbora Gallagher, Benjamin Gralher, Barbara Herbstritt, Pedro Hervé-Fernández, Christophe Hissler, Paul Koeniger, Arnaud Legout, Chandelle Joan Macdonald, Carlos Oyarzún, Regine Redelstein, Christof Seidler, Rolf Siegwolf, Christine Stumpp, Simon Thomsen, Markus Weiler, Christiane Werner, and Jeffrey J. McDonnell
Hydrol. Earth Syst. Sci., 22, 3619–3637, https://doi.org/10.5194/hess-22-3619-2018, https://doi.org/10.5194/hess-22-3619-2018, 2018
Short summary
Short summary
To extract water from soils for isotopic analysis, cryogenic water extraction is the most widely used removal technique. This work presents results from a worldwide laboratory intercomparison test of cryogenic extraction systems. Our results showed large differences in retrieved isotopic signatures among participating laboratories linked to interactions between soil type and properties, system setup, extraction efficiency, extraction system leaks, and each lab’s internal accuracy.
Tobias Houska, David Kraus, Ralf Kiese, and Lutz Breuer
Biogeosciences, 14, 3487–3508, https://doi.org/10.5194/bg-14-3487-2017, https://doi.org/10.5194/bg-14-3487-2017, 2017
Short summary
Short summary
CO2 and N2O are two prominent GHGs contributing to global warming. We combined measurement and modelling to quantify GHG emissions from adjacent arable, forest and grassland sites in Germany. Measured emissions reveal seasonal patterns and management effects like fertilizer application, tillage, harvest and grazing. Modelling helps to estimate the magnitude and uncertainty of not measurable C and N fluxes and indicates missing input source, e.g. nitrate uptake from groundwater.
David Pelster, Mariana Rufino, Todd Rosenstock, Joash Mango, Gustavo Saiz, Eugenio Diaz-Pines, German Baldi, and Klaus Butterbach-Bahl
Biogeosciences, 14, 187–202, https://doi.org/10.5194/bg-14-187-2017, https://doi.org/10.5194/bg-14-187-2017, 2017
Short summary
Short summary
In order to quantify greenhouse gas fluxes from typical eastern African smallholder farms, we measured flux rates every week for 1 year at 59 farms in western Kenya. These upland soils tend to be small sinks for CH4 and small sources of N2O. The management intensity of the farm plots had no effect on emissions, likely because the variability was low. Plots with trees had higher CH4 uptake than other plots. This suggests that emissions from small, low-input farms in this region are quite low.
Rosa Maria Roman-Cuesta, Martin Herold, Mariana C. Rufino, Todd S. Rosenstock, Richard A. Houghton, Simone Rossi, Klaus Butterbach-Bahl, Stephen Ogle, Benjamin Poulter, Louis Verchot, Christopher Martius, and Sytze de Bruin
Biogeosciences, 13, 5799–5819, https://doi.org/10.5194/bg-13-5799-2016, https://doi.org/10.5194/bg-13-5799-2016, 2016
Short summary
Short summary
The land use sector (AFOLU) is a pivotal component of countries' mitigation commitments under the Paris Agreement. Global land use data are therefore important to complement and fill in countries' data gaps. But how different are the existing AFOLU datasets and why? Here we contrast six AFOLU datasets for the tropics at different levels of aggregation (spatial, gases, emission sources) and point out possible reasons for the observed differences and the next steps to improve land use emissions.
Natalie Orlowski, Philipp Kraft, Jakob Pferdmenges, and Lutz Breuer
Hydrol. Earth Syst. Sci., 20, 3873–3894, https://doi.org/10.5194/hess-20-3873-2016, https://doi.org/10.5194/hess-20-3873-2016, 2016
Short summary
Short summary
The 2-year measurements of δ2H and δ18O in rainfall, stream, soil, and groundwater revealed that surface and groundwater are isotopically disconnected from the annual precipitation cycle but showed bidirectional interactions in the Schwingbach catchment. We established a hydrological model to estimate spatially distributed groundwater ages and flow directions. Our model revealed complex age dynamics and showed that runoff must have been stored in the catchment for much longer than event water.
Rosa Maria Roman-Cuesta, Mariana C. Rufino, Martin Herold, Klaus Butterbach-Bahl, Todd S. Rosenstock, Mario Herrero, Stephen Ogle, Changsheng Li, Benjamin Poulter, Louis Verchot, Christopher Martius, John Stuiver, and Sytze de Bruin
Biogeosciences, 13, 4253–4269, https://doi.org/10.5194/bg-13-4253-2016, https://doi.org/10.5194/bg-13-4253-2016, 2016
Short summary
Short summary
This research provides spatial data on gross emissions from the land use sector for the tropical region for the period 2000–2005. This sector contributes up to 24 % of the global emissions, but there is little understanding of where the hotspots of emissions are, how uncertain they are, and what the human activities behind these emissions are. Data provided here should assist countries to identify priority areas for mitigation action and contrast the effectiveness of their current measures.
Giovanny M. Mosquera, Catalina Segura, Kellie B. Vaché, David Windhorst, Lutz Breuer, and Patricio Crespo
Hydrol. Earth Syst. Sci., 20, 2987–3004, https://doi.org/10.5194/hess-20-2987-2016, https://doi.org/10.5194/hess-20-2987-2016, 2016
Short summary
Short summary
This study focuses on the investigation of baseflow mean transit times (MTTs) in a high-elevation tropical ecosystem (páramo) using stable water isotopes. Results showed short MTTs (< 9 months) and topographic controls on their spatial variability. We conclude that (1) the hydrology of the ecosystem is dominated by shallow subsurface flow and (2) the interplay between the high storage capacity of the páramo soils and the catchments' slopes provides the ecosystem with high regulation capacity.
Andrea Ghirardo, Junfei Xie, Xunhua Zheng, Yuesi Wang, Rüdiger Grote, Katja Block, Jürgen Wildt, Thomas Mentel, Astrid Kiendler-Scharr, Mattias Hallquist, Klaus Butterbach-Bahl, and Jörg-Peter Schnitzler
Atmos. Chem. Phys., 16, 2901–2920, https://doi.org/10.5194/acp-16-2901-2016, https://doi.org/10.5194/acp-16-2901-2016, 2016
Short summary
Short summary
Trees can impact urban air quality. Large emissions of plant volatiles are emitted in Beijing as a stress response to the urban polluted environment, but their impacts on secondary particulate matter remain relatively low compared to those originated from anthropogenic activities. The present study highlights the importance of including stress-induced compounds when studying plant volatile emissions.
D. Fowler, C. E. Steadman, D. Stevenson, M. Coyle, R. M. Rees, U. M. Skiba, M. A. Sutton, J. N. Cape, A. J. Dore, M. Vieno, D. Simpson, S. Zaehle, B. D. Stocker, M. Rinaldi, M. C. Facchini, C. R. Flechard, E. Nemitz, M. Twigg, J. W. Erisman, K. Butterbach-Bahl, and J. N. Galloway
Atmos. Chem. Phys., 15, 13849–13893, https://doi.org/10.5194/acp-15-13849-2015, https://doi.org/10.5194/acp-15-13849-2015, 2015
A. H. Aubert, O. Schnepel, P. Kraft, T. Houska, I. Plesca, N. Orlowski, and L. Breuer
Hydrol. Earth Syst. Sci. Discuss., https://doi.org/10.5194/hessd-12-11591-2015, https://doi.org/10.5194/hessd-12-11591-2015, 2015
Revised manuscript not accepted
Short summary
Short summary
Studienlandschaft Schwingbachtal is an out-door full-scale study site since 2008. It deals with hydrology in an interdisciplinary approach and enhances active learning by various means (field monitoring, education trails and geocache). In order to adapt to the change in students habits and to suit better as a communication tool for the locals, it is newly equipped with augmented reality which adds virtual objects on the real landscape, making learning pleasant.
M. Liu, M. Dannenmann, S. Lin, G. Saiz, G. Yan, Z. Yao, D. E. Pelster, H. Tao, S. Sippel, Y. Tao, Y. Zhang, X. Zheng, Q. Zuo, and K. Butterbach-Bahl
Biogeosciences, 12, 4831–4840, https://doi.org/10.5194/bg-12-4831-2015, https://doi.org/10.5194/bg-12-4831-2015, 2015
Short summary
Short summary
We demonstrate for the first time that a ground cover rice production system (GCRPS) significantly increased soil organic C and total N stocks at spatially representative paired sites under varying edaphic conditions. Our results suggest that GCRPS is a stable and sustainable technique that maintains key soil functions, while increasing rice yield and expanding the cultivation into regions where it has been hampered by low seasonal temperatures and/or a lack of irrigation water.
S. Carter, M. Herold, M. C. Rufino, K. Neumann, L. Kooistra, and L. Verchot
Biogeosciences, 12, 4809–4825, https://doi.org/10.5194/bg-12-4809-2015, https://doi.org/10.5194/bg-12-4809-2015, 2015
Short summary
Short summary
Emission from agriculture-driven deforestation can be mitigated by reducing the expansion of agriculture into forests through intensification and utilizing non-forested land for agriculture. Climate-smart agriculture can reduce emissions from existing agricultural land. Tropical countries which are priorities for action can be identified by assessing the mitigation potential of these interventions, by assessing capacity for implementation and the risks associated with these approaches.
S. Multsch, J.-F. Exbrayat, M. Kirby, N. R. Viney, H.-G. Frede, and L. Breuer
Geosci. Model Dev., 8, 1233–1244, https://doi.org/10.5194/gmd-8-1233-2015, https://doi.org/10.5194/gmd-8-1233-2015, 2015
Short summary
Short summary
Irrigation agriculture is required to sustain yields that allow feeding the world population. A robust assessment of irrigation requirement (IRR) relies on a sound quantification of evapotranspiration (ET). We prepared a multi-model ensemble considering several ET methods and investigate uncertainties in simulating IRR. More generally, we provide an example of the value of investigating the uncertainty in models that may be used to inform policy-making and to elaborate best management practices.
E. Timbe, D. Windhorst, R. Celleri, L. Timbe, P. Crespo, H.-G. Frede, J. Feyen, and L. Breuer
Hydrol. Earth Syst. Sci., 19, 1153–1168, https://doi.org/10.5194/hess-19-1153-2015, https://doi.org/10.5194/hess-19-1153-2015, 2015
Short summary
Short summary
Stream, soil and precipitation waters were collected in a tropical montane cloud forest catchment for 2 years and analyzed for stable water isotopes in order to infer transit time distribution functions and mean transit times for semi-steady-state conditions. Samples were aggregated to diverse sampling resolutions for checking the sensitivity of sampling frequency on lumped-model predictions. Results provide valuable information for the planning of future fieldwork in similar catchments.
Z. Yao, Y. Du, Y. Tao, X. Zheng, C. Liu, S. Lin, and K. Butterbach-Bahl
Biogeosciences, 11, 6221–6236, https://doi.org/10.5194/bg-11-6221-2014, https://doi.org/10.5194/bg-11-6221-2014, 2014
C. Werner, K. Reiser, M. Dannenmann, L. B. Hutley, J. Jacobeit, and K. Butterbach-Bahl
Biogeosciences, 11, 6047–6065, https://doi.org/10.5194/bg-11-6047-2014, https://doi.org/10.5194/bg-11-6047-2014, 2014
Short summary
Short summary
Atmospheric loss of N from savanna soil was dominated by N2 emissions (82-99% of total N loss to atmosphere). Nitric oxide emissions significantly contributed at 50% WFPS; high temperatures and N2O emissions were negligible. Based on a simple upscale approach we estimated annual loss of N to the atmosphere at 7.5kg yr-1. N2O emission was low for most samples, but high for a small subset of cores at 75% WFPS (due to short periods where such conditions occur this has little effect on totals).
D. Windhorst, P. Kraft, E. Timbe, H.-G. Frede, and L. Breuer
Hydrol. Earth Syst. Sci., 18, 4113–4127, https://doi.org/10.5194/hess-18-4113-2014, https://doi.org/10.5194/hess-18-4113-2014, 2014
E. Timbe, D. Windhorst, P. Crespo, H.-G. Frede, J. Feyen, and L. Breuer
Hydrol. Earth Syst. Sci., 18, 1503–1523, https://doi.org/10.5194/hess-18-1503-2014, https://doi.org/10.5194/hess-18-1503-2014, 2014
N. Orlowski, H.-G. Frede, N. Brüggemann, and L. Breuer
J. Sens. Sens. Syst., 2, 179–193, https://doi.org/10.5194/jsss-2-179-2013, https://doi.org/10.5194/jsss-2-179-2013, 2013
S. Multsch, Y. A. Al-Rumaikhani, H.-G. Frede, and L. Breuer
Geosci. Model Dev., 6, 1043–1059, https://doi.org/10.5194/gmd-6-1043-2013, https://doi.org/10.5194/gmd-6-1043-2013, 2013
G. J. Luo, R. Kiese, B. Wolf, and K. Butterbach-Bahl
Biogeosciences, 10, 3205–3219, https://doi.org/10.5194/bg-10-3205-2013, https://doi.org/10.5194/bg-10-3205-2013, 2013
S. Metzger, W. Junkermann, M. Mauder, K. Butterbach-Bahl, B. Trancón y Widemann, F. Neidl, K. Schäfer, S. Wieneke, X. H. Zheng, H. P. Schmid, and T. Foken
Biogeosciences, 10, 2193–2217, https://doi.org/10.5194/bg-10-2193-2013, https://doi.org/10.5194/bg-10-2193-2013, 2013
D. R. Cameron, M. Van Oijen, C. Werner, K. Butterbach-Bahl, R. Grote, E. Haas, G. B. M. Heuvelink, R. Kiese, J. Kros, M. Kuhnert, A. Leip, G. J. Reinds, H. I. Reuter, M. J. Schelhaas, W. De Vries, and J. Yeluripati
Biogeosciences, 10, 1751–1773, https://doi.org/10.5194/bg-10-1751-2013, https://doi.org/10.5194/bg-10-1751-2013, 2013
D. Windhorst, T. Waltz, E. Timbe, H.-G. Frede, and L. Breuer
Hydrol. Earth Syst. Sci., 17, 409–419, https://doi.org/10.5194/hess-17-409-2013, https://doi.org/10.5194/hess-17-409-2013, 2013
N. Gharahi Ghehi, C. Werner, K. Hufkens, R. Kiese, E. Van Ranst, D. Nsabimana, G. Wallin, L. Klemedtsson, K. Butterbach-Bahl, and P. Boeckx
Biogeosciences Discuss., https://doi.org/10.5194/bgd-10-1483-2013, https://doi.org/10.5194/bgd-10-1483-2013, 2013
Revised manuscript not accepted
J.-F. Exbrayat, N. R. Viney, H.-G. Frede, and L. Breuer
Geosci. Model Dev., 6, 117–125, https://doi.org/10.5194/gmd-6-117-2013, https://doi.org/10.5194/gmd-6-117-2013, 2013
Related subject area
Subject: Catchment hydrology | Techniques and Approaches: Modelling approaches
Technical note: What does the Standardized Streamflow Index actually reflect? Insights and implications for hydrological drought analysis
Long short-term memory networks for enhancing real-time flood forecasts: a case study for an underperforming hydrologic model
Assessing the value of high-resolution rainfall and streamflow data for hydrological modeling: an analysis based on 63 catchments in southeast China
Catchments do not strictly follow Budyko curves over multiple decades, but deviations are minor and predictable
Scale dependency in modeling nivo-glacial hydrological systems: the case of the Arolla basin, Switzerland
Extended-range forecasting of stream water temperature with deep-learning models
Technical note: An approach for handling multiple temporal frequencies with different input dimensions using a single LSTM cell
Projections of streamflow intermittence under climate change in European drying river networks
Economic valuation of subsurface water contributions to watershed ecosystem services using a fully integrated groundwater–surface-water model
Analyzing the generalization capabilities of a hybrid hydrological model for extrapolation to extreme events
CH-RUN: a deep-learning-based spatially contiguous runoff reconstruction for Switzerland
Runoff component quantification and future streamflow projection in a large mountainous basin based on a multidata-constrained cryospheric–hydrological model
Exploring the potential processes controlling changes in precipitation–runoff relationships in non-stationary environments
A diversity-centric strategy for the selection of spatio-temporal training data for LSTM-based streamflow forecasting
Simulating the Tone River eastward diversion project in Japan carried out 4 centuries ago
Lack of robustness of hydrological models: a large-sample diagnosis and an attempt to identify hydrological and climatic drivers
Achieving water budget closure through physical hydrological process modelling: insights from a large-sample study
Heavy-tailed flood peak distributions: what is the effect of the spatial variability of rainfall and runoff generation?
State updating of the Xin'anjiang model: joint assimilating streamflow and multi-source soil moisture data via the asynchronous ensemble Kalman filter with enhanced error models
Improving the hydrological consistency of a process-based solute-transport model by simultaneous calibration of streamflow and stream concentrations
Leveraging a time-series event separation method to disentangle time-varying hydrologic controls on streamflow – application to wildfire-affected catchments
The significance of the leaf area index for evapotranspiration estimation in SWAT-T for characteristic land cover types of West Africa
Improved representation of soil moisture processes through incorporation of cosmic-ray neutron count measurements in a large-scale hydrologic model
Spatio-temporal patterns and trends of streamflow in water-scarce Mediterranean basins
A large-sample modelling approach towards integrating streamflow and evaporation data for the Spanish catchments
Seasonal variation in land cover estimates reveals sensitivities and opportunities for environmental models
Estimating response times, flow velocities, and roughness coefficients of Canadian Prairie basins
Learning landscape features from streamflow with autoencoders
Hydrological regime index for non-perennial rivers
On the use of streamflow transformations for hydrological model calibration
Simulation-based inference for parameter estimation of complex watershed simulators
Multi-scale soil moisture data and process-based modeling reveal the importance of lateral groundwater flow in a subarctic catchment
CONCN: A high-resolution, integrated surface water-groundwater ParFlow modeling platform of continental China
Catchment response to climatic variability: implications for root zone storage and streamflow predictions
Assesing the Value of High-Resolution Data and Parameters Transferability Across Temporal Scales in Hydrological Modeling: A Case Study in Northern China
Hybrid hydrological modeling for large alpine basins: a semi-distributed approach
Technical note: How many models do we need to simulate hydrologic processes across large geographical domains?
Karst aquifer discharge response to rainfall interpreted as anomalous transport
HESS Opinions: Never train a Long Short-Term Memory (LSTM) network on a single basin
Large-sample hydrology – a few camels or a whole caravan?
Comment on “Are soils overrated in hydrology?” by Gao et al. (2023)
Multi-decadal fluctuations in root zone storage capacity through vegetation adaptation to hydro-climatic variability have minor effects on the hydrological response in the Neckar River basin, Germany
Projected future changes in the cryosphere and hydrology of a mountainous catchment in the upper Heihe River, China
On the importance of plant phenology in the evaporative process of a semi-arid woodland: could it be why satellite-based evaporation estimates in the miombo differ?
Assessing the adequacy of traditional hydrological models for climate change impact studies: A case for long-short-term memory (LSTM) neural networks
Regionalization of GR4J model parameters for river flow prediction in Paraná, Brazil
Evolution of river regimes in the Mekong River basin over 8 decades and the role of dams in recent hydrological extremes
Skill of seasonal flow forecasts at catchment scale: an assessment across South Korea
To what extent do flood-inducing storm events change future flood hazards?
When ancient numerical demons meet physics-informed machine learning: adjoint-based gradients for implicit differentiable modeling
Fabián Lema, Pablo A. Mendoza, Nicolás A. Vásquez, Naoki Mizukami, Mauricio Zambrano-Bigiarini, and Ximena Vargas
Hydrol. Earth Syst. Sci., 29, 1981–2002, https://doi.org/10.5194/hess-29-1981-2025, https://doi.org/10.5194/hess-29-1981-2025, 2025
Short summary
Short summary
Hydrological droughts affect ecosystems and socioeconomic activities worldwide. Despite the fact that they are commonly described with the Standardized Streamflow Index (SSI), there is limited understanding of what they truly reflect in terms of water cycle processes. Here, we used state-of-the-art hydrological models in Andean basins to examine drivers of SSI fluctuations. The results highlight the importance of careful selection of indices and timescales for accurate drought characterization and monitoring.
Sebastian Gegenleithner, Manuel Pirker, Clemens Dorfmann, Roman Kern, and Josef Schneider
Hydrol. Earth Syst. Sci., 29, 1939–1962, https://doi.org/10.5194/hess-29-1939-2025, https://doi.org/10.5194/hess-29-1939-2025, 2025
Short summary
Short summary
Accurate early-warning systems are crucial for reducing the damage caused by flooding events. In this study, we explored the potential of long short-term memory networks for enhancing the forecast accuracy of hydrologic models employed in operational flood forecasting. The presented approach elevated the investigated hydrologic model’s forecast accuracy for further ahead predictions and at flood event runoff.
Mahmut Tudaji, Yi Nan, and Fuqiang Tian
Hydrol. Earth Syst. Sci., 29, 1919–1937, https://doi.org/10.5194/hess-29-1919-2025, https://doi.org/10.5194/hess-29-1919-2025, 2025
Short summary
Short summary
Common intuition holds that higher input data resolution leads to better results. To assess the benefits of high-resolution data, we conduct simulation experiments using data with various temporal resolutions across multiple catchments and find that higher-resolution data do not always improve model performance, challenging the necessity of pursuing such data. In catchments with small areas or significant flow variability, high-resolution data is more valuable.
Muhammad Ibrahim, Miriam Coenders-Gerrits, Ruud van der Ent, and Markus Hrachowitz
Hydrol. Earth Syst. Sci., 29, 1703–1723, https://doi.org/10.5194/hess-29-1703-2025, https://doi.org/10.5194/hess-29-1703-2025, 2025
Short summary
Short summary
The quantification of precipitation into evaporation and runoff is vital for water resources management. The Budyko framework, based on aridity and evaporative indices of a catchment, can be an ideal tool for that. However, recent research highlights deviations of catchments from the expected evaporative index, casting doubt on its reliability. This study quantifies deviations of 2387 catchments, finding them minor and predictable. Integrating these into predictions upholds the framework's efficacy.
Anne-Laure Argentin, Pascal Horton, Bettina Schaefli, Jamal Shokory, Felix Pitscheider, Leona Repnik, Mattia Gianini, Simone Bizzi, Stuart N. Lane, and Francesco Comiti
Hydrol. Earth Syst. Sci., 29, 1725–1748, https://doi.org/10.5194/hess-29-1725-2025, https://doi.org/10.5194/hess-29-1725-2025, 2025
Short summary
Short summary
In this article, we show that by taking the optimal parameters calibrated with a semi-lumped model for the discharge at a catchment's outlet, we can accurately simulate runoff at various points within the study area, including three nested and three neighboring catchments. In addition, we demonstrate that employing more intricate melt models, which better represent physical processes, enhances the transfer of parameters in the simulation, until we observe overparameterization.
Ryan S. Padrón, Massimiliano Zappa, Luzi Bernhard, and Konrad Bogner
Hydrol. Earth Syst. Sci., 29, 1685–1702, https://doi.org/10.5194/hess-29-1685-2025, https://doi.org/10.5194/hess-29-1685-2025, 2025
Short summary
Short summary
We generate operational forecasts of daily maximum stream water temperature for 32 consecutive days at 54 stations in Switzerland with our best-performing data-driven model. The average forecast error is 0.38 °C for 1 d ahead and increases to 0.90 °C for 32 d ahead given the uncertainty in the meteorological variables influencing water temperature. Here we compare the skill of several models, how well they can forecast at new and ungauged stations, and the importance of different model inputs.
Eduardo Acuña Espinoza, Frederik Kratzert, Daniel Klotz, Martin Gauch, Manuel Álvarez Chaves, Ralf Loritz, and Uwe Ehret
Hydrol. Earth Syst. Sci., 29, 1749–1758, https://doi.org/10.5194/hess-29-1749-2025, https://doi.org/10.5194/hess-29-1749-2025, 2025
Short summary
Short summary
Long short-term memory (LSTM) networks have demonstrated state-of-the-art performance for rainfall-runoff hydrological modelling. However, most studies focus on predictions at a daily scale, limiting the benefits of sub-daily (e.g. hourly) predictions in applications like flood forecasting. In this study, we introduce a new architecture, multi-frequency LSTM (MF-LSTM), designed to use inputs of various temporal frequencies to produce sub-daily (e.g. hourly) predictions at a moderate computational cost.
Louise Mimeau, Annika Künne, Alexandre Devers, Flora Branger, Sven Kralisch, Claire Lauvernet, Jean-Philippe Vidal, Núria Bonada, Zoltán Csabai, Heikki Mykrä, Petr Pařil, Luka Polović, and Thibault Datry
Hydrol. Earth Syst. Sci., 29, 1615–1636, https://doi.org/10.5194/hess-29-1615-2025, https://doi.org/10.5194/hess-29-1615-2025, 2025
Short summary
Short summary
Our study projects how climate change will affect the drying of river segments and stream networks in Europe, using advanced modelling techniques to assess changes in six river networks across diverse ecoregions. We found that drying events will become more frequent and intense and will start earlier or last longer, potentially turning some river sections from perennial to intermittent. The results are valuable for river ecologists for evaluating the ecological health of river ecosystem.
Tariq Aziz, Steven K. Frey, David R. Lapen, Susan Preston, Hazen A. J. Russell, Omar Khader, Andre R. Erler, and Edward A. Sudicky
Hydrol. Earth Syst. Sci., 29, 1549–1568, https://doi.org/10.5194/hess-29-1549-2025, https://doi.org/10.5194/hess-29-1549-2025, 2025
Short summary
Short summary
This study determines the value of subsurface water for ecosystem services' supply in an agricultural watershed in Ontario, Canada. Using a fully integrated water model and an economic valuation approach, the research highlights subsurface water's critical role in maintaining watershed ecosystem services. The study informs on the sustainable use of subsurface water and introduces a new method for managing watershed ecosystem services.
Eduardo Acuña Espinoza, Ralf Loritz, Frederik Kratzert, Daniel Klotz, Martin Gauch, Manuel Álvarez Chaves, and Uwe Ehret
Hydrol. Earth Syst. Sci., 29, 1277–1294, https://doi.org/10.5194/hess-29-1277-2025, https://doi.org/10.5194/hess-29-1277-2025, 2025
Short summary
Short summary
Data-driven techniques have shown the potential to outperform process-based models in rainfall–runoff simulations. Hybrid models, combining both approaches, aim to enhance accuracy and maintain interpretability. Expanding the set of test cases to evaluate hybrid models under different conditions, we test their generalization capabilities for extreme hydrological events.
Basil Kraft, Michael Schirmer, William H. Aeberhard, Massimiliano Zappa, Sonia I. Seneviratne, and Lukas Gudmundsson
Hydrol. Earth Syst. Sci., 29, 1061–1082, https://doi.org/10.5194/hess-29-1061-2025, https://doi.org/10.5194/hess-29-1061-2025, 2025
Short summary
Short summary
This study reconstructs daily runoff in Switzerland (1962–2023) using a deep-learning model, providing a spatially contiguous dataset on a medium-sized catchment grid. The model outperforms traditional hydrological methods, revealing shifts in Swiss water resources, including more frequent dry years and declining summer runoff. The reconstruction is publicly available.
Mengjiao Zhang, Yi Nan, and Fuqiang Tian
Hydrol. Earth Syst. Sci., 29, 1033–1060, https://doi.org/10.5194/hess-29-1033-2025, https://doi.org/10.5194/hess-29-1033-2025, 2025
Short summary
Short summary
Owing to differences in the existing published results, we conducted a detailed analysis of the runoff components and future trends in the Yarlung Tsangpo River basin and found that the contributions of snowmelt and glacier melt runoff to streamflow (both ~5 %) are limited and much lower than previous results. The streamflow in this area will continuously increase in the future, but the overestimated contribution of glacier melt could lead to an underestimation of this increasing trend.
Tian Lan, Tongfang Li, Hongbo Zhang, Jiefeng Wu, Yongqin David Chen, and Chong-Yu Xu
Hydrol. Earth Syst. Sci., 29, 903–924, https://doi.org/10.5194/hess-29-903-2025, https://doi.org/10.5194/hess-29-903-2025, 2025
Short summary
Short summary
This study develops an integrated framework based on the novel Driving index for changes in Precipitation–Runoff Relationships (DPRR) to explore the controlling changes in precipitation–runoff relationships in non-stationary environments. According to the quantitative results of the candidate driving factors, the possible process explanations for changes in the precipitation–runoff relationships are deduced. The main contribution offers a comprehensive understanding of hydrological processes.
Everett Snieder and Usman T. Khan
Hydrol. Earth Syst. Sci., 29, 785–798, https://doi.org/10.5194/hess-29-785-2025, https://doi.org/10.5194/hess-29-785-2025, 2025
Short summary
Short summary
Improving the accuracy of flood forecasts is paramount to minimising flood damage. Machine learning (ML) models are increasingly being applied for flood forecasting. Such models are typically trained on large historic hydrometeorological datasets. In this work, we evaluate methods for selecting training datasets that maximise the spatio-temporal diversity of the represented hydrological processes. Empirical results showcase the importance of hydrological diversity in training ML models.
Joško Trošelj and Naota Hanasaki
Hydrol. Earth Syst. Sci., 29, 753–766, https://doi.org/10.5194/hess-29-753-2025, https://doi.org/10.5194/hess-29-753-2025, 2025
Short summary
Short summary
This study presents the first distributed hydrological simulation which confirms claims raised by historians that the eastward diversion project of the Tone River in Japan was conducted 4 centuries ago to increase low flows and subsequent travelling possibilities surrounding the capital, Edo (Tokyo), using inland navigation. We showed that great steps forward can be made for improving quality of life with small human engineering waterworks and small interventions in the regime of natural flows.
Léonard Santos, Vazken Andréassian, Torben O. Sonnenborg, Göran Lindström, Alban de Lavenne, Charles Perrin, Lila Collet, and Guillaume Thirel
Hydrol. Earth Syst. Sci., 29, 683–700, https://doi.org/10.5194/hess-29-683-2025, https://doi.org/10.5194/hess-29-683-2025, 2025
Short summary
Short summary
This work investigates how hydrological models are transferred to a period in which climate conditions are different to the ones of the period in which they were set up. The robustness assessment test built to detect dependencies between model error and climatic drivers was applied to three hydrological models in 352 catchments in Denmark, France and Sweden. Potential issues are seen in a significant number of catchments for the models, even though the catchments differ for each model.
Xudong Zheng, Dengfeng Liu, Shengzhi Huang, Hao Wang, and Xianmeng Meng
Hydrol. Earth Syst. Sci., 29, 627–653, https://doi.org/10.5194/hess-29-627-2025, https://doi.org/10.5194/hess-29-627-2025, 2025
Short summary
Short summary
Water budget non-closure is a widespread phenomenon among multisource datasets which undermines the robustness of hydrological inferences. This study proposes a Multisource Dataset Correction Framework grounded in Physical Hydrological Process Modelling to enhance water budget closure, termed PHPM-MDCF. We examined the efficiency and robustness of the framework using the CAMELS dataset and achieved an average reduction of 49 % in total water budget residuals across 475 CONUS basins.
Elena Macdonald, Bruno Merz, Viet Dung Nguyen, and Sergiy Vorogushyn
Hydrol. Earth Syst. Sci., 29, 447–463, https://doi.org/10.5194/hess-29-447-2025, https://doi.org/10.5194/hess-29-447-2025, 2025
Short summary
Short summary
Flood peak distributions indicate how likely the occurrence of an extreme flood is at a certain river. If the distribution has a so-called heavy tail, extreme floods are more likely than might be anticipated. We find heavier tails in small catchments compared to large catchments, and spatially variable rainfall leads to a lower occurrence probability of extreme floods. Spatially variable runoff does not show effects. The results can improve estimations of probabilities of extreme floods.
Junfu Gong, Xingwen Liu, Cheng Yao, Zhijia Li, Albrecht H. Weerts, Qiaoling Li, Satish Bastola, Yingchun Huang, and Junzeng Xu
Hydrol. Earth Syst. Sci., 29, 335–360, https://doi.org/10.5194/hess-29-335-2025, https://doi.org/10.5194/hess-29-335-2025, 2025
Short summary
Short summary
Our study introduces a new method to improve flood forecasting by combining soil moisture and streamflow data using an advanced data assimilation technique. By integrating field and reanalysis soil moisture data and assimilating this with streamflow measurements, we aim to enhance the accuracy of flood predictions. This approach reduces the accumulation of past errors in the initial conditions at the start of the forecast, helping to better prepare for and respond to floods.
Jordy Salmon-Monviola, Ophélie Fovet, and Markus Hrachowitz
Hydrol. Earth Syst. Sci., 29, 127–158, https://doi.org/10.5194/hess-29-127-2025, https://doi.org/10.5194/hess-29-127-2025, 2025
Short summary
Short summary
To increase the predictive power of hydrological models, it is necessary to improve their consistency, i.e. their physical realism, which is measured by the ability of the model to reproduce observed system dynamics. Using a model to represent the dynamics of water and nitrate and dissolved organic carbon concentrations in an agricultural catchment, we showed that using solute-concentration data for calibration is useful to improve the hydrological consistency of the model.
Haley A. Canham, Belize Lane, Colin B. Phillips, and Brendan P. Murphy
Hydrol. Earth Syst. Sci., 29, 27–43, https://doi.org/10.5194/hess-29-27-2025, https://doi.org/10.5194/hess-29-27-2025, 2025
Short summary
Short summary
The influence of watershed disturbances has proved challenging to disentangle from natural streamflow variability. This study evaluates the influence of time-varying hydrologic controls on rainfall–runoff in undisturbed and wildfire-disturbed watersheds using a novel time-series event separation method. Across watersheds, water year type and season influenced rainfall–runoff patterns. Accounting for these controls enabled clearer isolation of wildfire effects.
Fabian Merk, Timo Schaffhauser, Faizan Anwar, Ye Tuo, Jean-Martial Cohard, and Markus Disse
Hydrol. Earth Syst. Sci., 28, 5511–5539, https://doi.org/10.5194/hess-28-5511-2024, https://doi.org/10.5194/hess-28-5511-2024, 2024
Short summary
Short summary
Evapotranspiration (ET) is computed from the vegetation (plant transpiration) and soil (soil evaporation). In western Africa, plant transpiration correlates with vegetation growth. Vegetation is often represented using the leaf area index (LAI). In this study, we evaluate the importance of the LAI for ET calculation. We take a close look at this interaction and highlight its relevance. Our work contributes to the understanding of terrestrial water cycle processes .
Eshrat Fatima, Rohini Kumar, Sabine Attinger, Maren Kaluza, Oldrich Rakovec, Corinna Rebmann, Rafael Rosolem, Sascha E. Oswald, Luis Samaniego, Steffen Zacharias, and Martin Schrön
Hydrol. Earth Syst. Sci., 28, 5419–5441, https://doi.org/10.5194/hess-28-5419-2024, https://doi.org/10.5194/hess-28-5419-2024, 2024
Short summary
Short summary
This study establishes a framework to incorporate cosmic-ray neutron measurements into the mesoscale Hydrological Model (mHM). We evaluate different approaches to estimate neutron counts within the mHM using the Desilets equation, with uniformly and non-uniformly weighted average soil moisture, and the physically based code COSMIC. The data improved not only soil moisture simulations but also the parameterisation of evapotranspiration in the model.
Laia Estrada, Xavier Garcia, Joan Saló-Grau, Rafael Marcé, Antoni Munné, and Vicenç Acuña
Hydrol. Earth Syst. Sci., 28, 5353–5373, https://doi.org/10.5194/hess-28-5353-2024, https://doi.org/10.5194/hess-28-5353-2024, 2024
Short summary
Short summary
Hydrological modelling is a powerful tool to support decision-making. We assessed spatio-temporal patterns and trends of streamflow for 2001–2022 with a hydrological model, integrating stakeholder expert knowledge on management operations. The results provide insight into how climate change and anthropogenic pressures affect water resources availability in regions vulnerable to water scarcity, thus raising the need for sustainable management practices and integrated hydrological modelling.
Patricio Yeste, Matilde García-Valdecasas Ojeda, Sonia R. Gámiz-Fortis, Yolanda Castro-Díez, Axel Bronstert, and María Jesús Esteban-Parra
Hydrol. Earth Syst. Sci., 28, 5331–5352, https://doi.org/10.5194/hess-28-5331-2024, https://doi.org/10.5194/hess-28-5331-2024, 2024
Short summary
Short summary
Integrating streamflow and evaporation data can help improve the physical realism of hydrologic models. We investigate the capabilities of the Variable Infiltration Capacity (VIC) to reproduce both hydrologic variables for 189 headwater located in Spain. Results from sensitivity analyses indicate that adding two vegetation parameters is enough to improve the representation of evaporation and that the performance of VIC exceeded that of the largest modelling effort currently available in Spain.
Daniel T. Myers, David Jones, Diana Oviedo-Vargas, John Paul Schmit, Darren L. Ficklin, and Xuesong Zhang
Hydrol. Earth Syst. Sci., 28, 5295–5310, https://doi.org/10.5194/hess-28-5295-2024, https://doi.org/10.5194/hess-28-5295-2024, 2024
Short summary
Short summary
We studied how streamflow and water quality models respond to land cover data collected by satellites during the growing season versus the non-growing season. The land cover data showed more trees during the growing season and more built areas during the non-growing season. We next found that the use of non-growing season data resulted in a higher modeled nutrient export to streams. Knowledge of these sensitivities would be particularly important when models inform water resource management.
Kevin R. Shook, Paul H. Whitfield, Christopher Spence, and John W. Pomeroy
Hydrol. Earth Syst. Sci., 28, 5173–5192, https://doi.org/10.5194/hess-28-5173-2024, https://doi.org/10.5194/hess-28-5173-2024, 2024
Short summary
Short summary
Recent studies suggest that the velocities of water running off landscapes in the Canadian Prairies may be much smaller than generally assumed. Analyses of historical flows for 23 basins in central Alberta show that many of the rivers responded more slowly and that the flows are much slower than would be estimated from equations developed elsewhere. The effects of slow flow velocities on the development of hydrological models of the region are discussed, as are the possible causes.
Alberto Bassi, Marvin Höge, Antonietta Mira, Fabrizio Fenicia, and Carlo Albert
Hydrol. Earth Syst. Sci., 28, 4971–4988, https://doi.org/10.5194/hess-28-4971-2024, https://doi.org/10.5194/hess-28-4971-2024, 2024
Short summary
Short summary
The goal is to remove the impact of meteorological drivers in order to uncover the unique landscape fingerprints of a catchment from streamflow data. Our results reveal an optimal two-feature summary for most catchments, with a third feature associated with aridity and intermittent flow that is needed for challenging cases. Baseflow index, aridity, and soil or vegetation attributes strongly correlate with learnt features, indicating their importance for streamflow prediction.
Pablo Fernando Dornes and Rocío Noelia Comas
Hydrol. Earth Syst. Sci. Discuss., https://doi.org/10.5194/hess-2024-338, https://doi.org/10.5194/hess-2024-338, 2024
Revised manuscript accepted for HESS
Short summary
Short summary
The Desaguadero-Salado-Chadiluevú-Curacó (DSCC) River is a semiarid river which is severely dammed in its tributaries which collect the snowmelt runoff. This runoff feeds mostly gravitational irrigation systems of very low efficiency. As a result, the DSCC River does not have natural runoff. The proposed Hydrological Regime Index (HRI) is able to discriminate and quantify regime alterations under permanent and non-permanent flow conditions and with low and high impoundment conditions.
Guillaume Thirel, Léonard Santos, Olivier Delaigue, and Charles Perrin
Hydrol. Earth Syst. Sci., 28, 4837–4860, https://doi.org/10.5194/hess-28-4837-2024, https://doi.org/10.5194/hess-28-4837-2024, 2024
Short summary
Short summary
We discuss how mathematical transformations impact calibrated hydrological model simulations. We assess how 11 transformations behave over the complete range of streamflows. Extreme transformations lead to models that are specialized for extreme streamflows but show poor performance outside the range of targeted streamflows and are less robust. We show that no a priori assumption about transformations can be taken as warranted.
Robert Hull, Elena Leonarduzzi, Luis De La Fuente, Hoang Viet Tran, Andrew Bennett, Peter Melchior, Reed M. Maxwell, and Laura E. Condon
Hydrol. Earth Syst. Sci., 28, 4685–4713, https://doi.org/10.5194/hess-28-4685-2024, https://doi.org/10.5194/hess-28-4685-2024, 2024
Short summary
Short summary
Large-scale hydrologic simulators are a needed tool to explore complex watershed processes and how they may evolve with a changing climate. However, calibrating them can be difficult because they are costly to run and have many unknown parameters. We implement a state-of-the-art approach to model calibration using neural networks with a set of experiments based on streamflow in the upper Colorado River basin.
Jari-Pekka Nousu, Kersti Leppä, Hannu Marttila, Pertti Ala-aho, Giulia Mazzotti, Terhikki Manninen, Mika Korkiakoski, Mika Aurela, Annalea Lohila, and Samuli Launiainen
Hydrol. Earth Syst. Sci., 28, 4643–4666, https://doi.org/10.5194/hess-28-4643-2024, https://doi.org/10.5194/hess-28-4643-2024, 2024
Short summary
Short summary
We used hydrological models, field measurements, and satellite-based data to study the soil moisture dynamics in a subarctic catchment. The role of groundwater was studied with different ways to model the groundwater dynamics and via comparisons to the observational data. The choice of groundwater model was shown to have a strong impact, and representation of lateral flow was important to capture wet soil conditions. Our results provide insights for ecohydrological studies in boreal regions.
Chen Yang, Zitong Jia, Wenjie Xu, Zhongwang Wei, Xiaolang Zhang, Yiguang Zou, Jeffrey McDonnell, Laura Condon, Yongjiu Dai, and Reed Maxwell
Hydrol. Earth Syst. Sci. Discuss., https://doi.org/10.5194/hess-2024-292, https://doi.org/10.5194/hess-2024-292, 2024
Revised manuscript accepted for HESS
Short summary
Short summary
We developed the first high-resolution, integrated surface water-groundwater hydrologic model of the entire continental China using ParFlow. The model shows good performance of streamflow and water table depth when compared to global data products and observations. It is essential for water resources management and decision making in China within a consistent framework in the changing world. It also has significant implications for similar modeling in other places in the world.
Nienke Tempel, Laurène Bouaziz, Riccardo Taormina, Ellis van Noppen, Jasper Stam, Eric Sprokkereef, and Markus Hrachowitz
Hydrol. Earth Syst. Sci., 28, 4577–4597, https://doi.org/10.5194/hess-28-4577-2024, https://doi.org/10.5194/hess-28-4577-2024, 2024
Short summary
Short summary
This study explores the impact of climatic variability on root zone water storage capacities and, thus, on hydrological predictions. Analysing data from 286 areas in Europe and the US, we found that, despite some variations in root zone storage capacity due to changing climatic conditions over multiple decades, these changes are generally minor and have a limited effect on water storage and river flow predictions.
Mahmut Tudaji, Yi Nan, and Fuqiang Tian
EGUsphere, https://doi.org/10.5194/egusphere-2024-2966, https://doi.org/10.5194/egusphere-2024-2966, 2024
Short summary
Short summary
We assessed the value of high-resolution data and parameters transferability across temporal scales based on 7 catchments in northern China. We found that higher resolution data does not always improve model performance, questioning the need for such data; Model parameters are transferable across different data resolutions, but not across computational time steps. It is recommended to utilize smaller computational time step when building hydrological models even without high-resolution data.
Bu Li, Ting Sun, Fuqiang Tian, Mahmut Tudaji, Li Qin, and Guangheng Ni
Hydrol. Earth Syst. Sci., 28, 4521–4538, https://doi.org/10.5194/hess-28-4521-2024, https://doi.org/10.5194/hess-28-4521-2024, 2024
Short summary
Short summary
This paper developed hybrid semi-distributed hydrological models by employing a process-based model as the backbone and utilizing deep learning to parameterize and replace internal modules. The main contribution is to provide a high-performance tool enriched with explicit hydrological knowledge for hydrological prediction and to improve understanding about the hydrological sensitivities to climate change in large alpine basins.
Wouter J. M. Knoben, Ashwin Raman, Gaby J. Gründemann, Mukesh Kumar, Alain Pietroniro, Chaopeng Shen, Yalan Song, Cyril Thébault, Katie van Werkhoven, Andrew W. Wood, and Martyn P. Clark
Hydrol. Earth Syst. Sci. Discuss., https://doi.org/10.5194/hess-2024-279, https://doi.org/10.5194/hess-2024-279, 2024
Revised manuscript accepted for HESS
Short summary
Short summary
Hydrologic models are needed to provide simulations of water availability, floods and droughts. The accuracy of these simulations is often quantified with so-called performance scores. A common thought is that different models are more or less applicable to different landscapes, depending on how the model works. We show that performance scores are not helpful in distinguishing between different models, and thus cannot easily be used to select an appropriate model for a specific place.
Dan Elhanati, Nadine Goeppert, and Brian Berkowitz
Hydrol. Earth Syst. Sci., 28, 4239–4249, https://doi.org/10.5194/hess-28-4239-2024, https://doi.org/10.5194/hess-28-4239-2024, 2024
Short summary
Short summary
A continuous time random walk framework was developed to allow modeling of a karst aquifer discharge response to measured rainfall. The application of the numerical model yielded robust fits between modeled and measured discharge values, especially for the distinctive long tails found during recession times. The findings shed light on the interplay of slow and fast flow in the karst system and establish the application of the model for simulating flow and transport in such systems.
Frederik Kratzert, Martin Gauch, Daniel Klotz, and Grey Nearing
Hydrol. Earth Syst. Sci., 28, 4187–4201, https://doi.org/10.5194/hess-28-4187-2024, https://doi.org/10.5194/hess-28-4187-2024, 2024
Short summary
Short summary
Recently, a special type of neural-network architecture became increasingly popular in hydrology literature. However, in most applications, this model was applied as a one-to-one replacement for hydrology models without adapting or rethinking the experimental setup. In this opinion paper, we show how this is almost always a bad decision and how using these kinds of models requires the use of large-sample hydrology data sets.
Franziska Clerc-Schwarzenbach, Giovanni Selleri, Mattia Neri, Elena Toth, Ilja van Meerveld, and Jan Seibert
Hydrol. Earth Syst. Sci., 28, 4219–4237, https://doi.org/10.5194/hess-28-4219-2024, https://doi.org/10.5194/hess-28-4219-2024, 2024
Short summary
Short summary
We show that the differences between the forcing data included in three CAMELS datasets (US, BR, GB) and the forcing data included for the same catchments in the Caravan dataset affect model calibration considerably. The model performance dropped when the data from the Caravan dataset were used instead of the original data. Most of the model performance drop could be attributed to the differences in precipitation data. However, differences were largest for the potential evapotranspiration data.
Ying Zhao, Mehdi Rahmati, Harry Vereecken, and Dani Or
Hydrol. Earth Syst. Sci., 28, 4059–4063, https://doi.org/10.5194/hess-28-4059-2024, https://doi.org/10.5194/hess-28-4059-2024, 2024
Short summary
Short summary
Gao et al. (2023) question the importance of soil in hydrology, sparking debate. We acknowledge some valid points but critique their broad, unsubstantiated views on soil's role. Our response highlights three key areas: (1) the false divide between ecosystem-centric and soil-centric approaches, (2) the vital yet varied impact of soil properties, and (3) the call for a scale-aware framework. We aim to unify these perspectives, enhancing hydrology's comprehensive understanding.
Siyuan Wang, Markus Hrachowitz, and Gerrit Schoups
Hydrol. Earth Syst. Sci., 28, 4011–4033, https://doi.org/10.5194/hess-28-4011-2024, https://doi.org/10.5194/hess-28-4011-2024, 2024
Short summary
Short summary
Root zone storage capacity (Sumax) changes significantly over multiple decades, reflecting vegetation adaptation to climatic variability. However, this temporal evolution of Sumax cannot explain long-term fluctuations in the partitioning of water fluxes as expressed by deviations ΔIE from the parametric Budyko curve over time with different climatic conditions, and it does not have any significant effects on shorter-term hydrological response characteristics of the upper Neckar catchment.
Zehua Chang, Hongkai Gao, Leilei Yong, Kang Wang, Rensheng Chen, Chuntan Han, Otgonbayar Demberel, Batsuren Dorjsuren, Shugui Hou, and Zheng Duan
Hydrol. Earth Syst. Sci., 28, 3897–3917, https://doi.org/10.5194/hess-28-3897-2024, https://doi.org/10.5194/hess-28-3897-2024, 2024
Short summary
Short summary
An integrated cryospheric–hydrologic model, FLEX-Cryo, was developed that considers glaciers, snow cover, and frozen soil and their dynamic impacts on hydrology. We utilized it to simulate future changes in cryosphere and hydrology in the Hulu catchment. Our projections showed the two glaciers will melt completely around 2050, snow cover will reduce, and permafrost will degrade. For hydrology, runoff will decrease after the glacier has melted, and permafrost degradation will increase baseflow.
Henry M. Zimba, Miriam Coenders-Gerrits, Kawawa E. Banda, Petra Hulsman, Nick van de Giesen, Imasiku A. Nyambe, and Hubert H. G. Savenije
Hydrol. Earth Syst. Sci., 28, 3633–3663, https://doi.org/10.5194/hess-28-3633-2024, https://doi.org/10.5194/hess-28-3633-2024, 2024
Short summary
Short summary
The fall and flushing of new leaves in the miombo woodlands co-occur in the dry season before the commencement of seasonal rainfall. The miombo species are also said to have access to soil moisture in deep soils, including groundwater in the dry season. Satellite-based evaporation estimates, temporal trends, and magnitudes differ the most in the dry season, most likely due to inadequate understanding and representation of the highlighted miombo species attributes in simulations.
Jean-Luc Martel, François Brissette, Richard Arsenault, Richard Turcotte, Mariana Castañeda-Gonzalez, William Armstrong, Edouard Mailhot, Jasmine Pelletier-Dumont, Gabriel Rondeau-Genesse, and Louis-Philippe Caron
EGUsphere, https://doi.org/10.5194/egusphere-2024-2133, https://doi.org/10.5194/egusphere-2024-2133, 2024
Short summary
Short summary
This study compares Long Short-Term Memory (LSTM) neural networks with traditional hydrological models to predict future streamflow under climate change. Using data from 148 catchments, it finds that LSTM models, which learn from extensive data sequences, perform differently and often better than traditional hydrolgical models. The continental LSTM model, which includes data from diverse climate zones, is particularly effective for understanding climate impacts on water resources.
Louise Akemi Kuana, Arlan Scortegagna Almeida, Emílio Graciliano Ferreira Mercuri, and Steffen Manfred Noe
Hydrol. Earth Syst. Sci., 28, 3367–3390, https://doi.org/10.5194/hess-28-3367-2024, https://doi.org/10.5194/hess-28-3367-2024, 2024
Short summary
Short summary
The authors compared regionalization methods for river flow prediction in 126 catchments from the south of Brazil, a region with humid subtropical and hot temperate climate. The regionalization method based on physiographic–climatic similarity had the best performance for predicting daily and Q95 reference flow. We showed that basins without flow monitoring can have a good approximation of streamflow using machine learning and physiographic–climatic information as inputs.
Huy Dang and Yadu Pokhrel
Hydrol. Earth Syst. Sci., 28, 3347–3365, https://doi.org/10.5194/hess-28-3347-2024, https://doi.org/10.5194/hess-28-3347-2024, 2024
Short summary
Short summary
By examining basin-wide simulations of a river regime over 83 years with and without dams, we present evidence that climate variation was a key driver of hydrologic variabilities in the Mekong River basin (MRB) over the long term; however, dams have largely altered the seasonality of the Mekong’s flow regime and annual flooding patterns in major downstream areas in recent years. These findings could help us rethink the planning of future dams and water resource management in the MRB.
Yongshin Lee, Francesca Pianosi, Andres Peñuela, and Miguel Angel Rico-Ramirez
Hydrol. Earth Syst. Sci., 28, 3261–3279, https://doi.org/10.5194/hess-28-3261-2024, https://doi.org/10.5194/hess-28-3261-2024, 2024
Short summary
Short summary
Following recent advancements in weather prediction technology, we explored how seasonal weather forecasts (1 or more months ahead) could benefit practical water management in South Korea. Our findings highlight that using seasonal weather forecasts for predicting flow patterns 1 to 3 months ahead is effective, especially during dry years. This suggest that seasonal weather forecasts can be helpful in improving the management of water resources.
Mariam Khanam, Giulia Sofia, and Emmanouil N. Anagnostou
Hydrol. Earth Syst. Sci., 28, 3161–3190, https://doi.org/10.5194/hess-28-3161-2024, https://doi.org/10.5194/hess-28-3161-2024, 2024
Short summary
Short summary
Flooding worsens due to climate change, with river dynamics being a key in local flood control. Predicting post-storm geomorphic changes is challenging. Using self-organizing maps and machine learning, this study forecasts post-storm alterations in stage–discharge relationships across 3101 US stream gages. The provided framework can aid in updating hazard assessments by identifying rivers prone to change, integrating channel adjustments into flood hazard assessment.
Yalan Song, Wouter J. M. Knoben, Martyn P. Clark, Dapeng Feng, Kathryn Lawson, Kamlesh Sawadekar, and Chaopeng Shen
Hydrol. Earth Syst. Sci., 28, 3051–3077, https://doi.org/10.5194/hess-28-3051-2024, https://doi.org/10.5194/hess-28-3051-2024, 2024
Short summary
Short summary
Differentiable models (DMs) integrate neural networks and physical equations for accuracy, interpretability, and knowledge discovery. We developed an adjoint-based DM for ordinary differential equations (ODEs) for hydrological modeling, reducing distorted fluxes and physical parameters from errors in models that use explicit and operation-splitting schemes. With a better numerical scheme and improved structure, the adjoint-based DM matches or surpasses long short-term memory (LSTM) performance.
Cited articles
Ali, G. A., Roy, A. G., Turmel, M.-C., and Courchesne, F.: Source-to-stream
connectivity assessment through end-member mixing analysis, J. Hydrol.,
392, 119–135, https://doi.org/10.1016/j.jhydrol.2010.07.049, 2010.
Asano, Y. and Uchida, T.: Flow path depth is the main controller of mean
base flow transit times in a mountainous catchment, Water Resour. Res.,
48, W03512, https://doi.org/10.1029/2011WR010906, 2012.
Ataroff, M. and Rada, F.: Deforestation impact on water dynamics in a
Venezuelan Andean cloud forest, Ambio, 29, 440–444,
https://doi.org/10.1579/0044-7447-29.7.440, 2000.
Baker, T. J. and Miller, S. N.: Using the Soil and Water Assessment Tool
(SWAT) to assess land use impact on water resources in an East African
watershed, J. Hydrol., 486, 100–111,
https://doi.org/10.1016/j.jhydrol.2013.01.041, 2013.
Baldyga, T. J., Miller, S. N., Shivoga, W., and Gichaba, M.: Assessing the
impact of land cover change in Kenya using remote sensing and hydrologic
modelling, in ASPRS Annual Conference Proceedings, Denver, Colorado, 2004.
Barthold, F. K., Wu, J., Vaché, K. B., Schneider, K., Frede, H.-G., and
Breuer, L.: Identification of geographic runoff sources in a data sparse
region: Hydrological processes and the limitations of tracer-based
approaches, Hydrol. Process., 24, 2313–2327, https://doi.org/10.1002/hyp.7678,
2010.
Barthold, F. K., Tyralla, C., Schneider, K., Vaché, K. B., Frede, H.-G.,
and Breuer, L.: How many tracers do we need for end member mixing analysis
(EMMA)? A sensitivity analysis, Water Resour. Res., 47, W08519,
https://doi.org/10.1029/2011WR010604, 2011.
Barthold, F. K., Turner, B. L., Elsenbeer, H., and Zimmermann, A.: A
hydrochemical approach to quantify the role of return flow in a surface
flow-dominated catchment, Hydrol. Process., 31, 1018–1033,
https://doi.org/10.1002/hyp.11083, 2017.
Beven, K. and Binley, A.: The future of distributed models: Model
calibration and uncertainty prediction, Hydrol. Process., 6, 279–298,
https://doi.org/10.1002/hyp.3360060305, 1992.
Bewernick, T.: Mapping forest degradation in the Mau Forest Complex using
NDFI time series, MS thesis, Wageningen University, Wageningen, the
Netherlands, August 2016.
Binge, F. W.: Geology of the Kericho area, Ministry of Commerce, Industry
and Communications, Geological Survey of Kenya, 1962.
Boy, J., Valarezo, C., and Wilcke, W.: Water flow paths in soil control
element exports in an Andean tropical montane forest, Eur. J. Soil Sci.,
59, 1209–1227, https://doi.org/10.1111/j.1365-2389.2008.01063.x, 2008.
Brown, K. W., Thomas, J. C., and Holder, M. W.: Development of a capillary
wick unsaturated zone pore water sampler, United States Environmental
Protection Agency, Las Vegas, USA, 1989.
Burns, D. A., McDonnell, J. J., Hooper, R. P., Peters, N. E., Freer, J. E.,
Kendall, C., and Beven, K.: Quantifying contributions to storm runoff through
end-member mixing analysis and hydrologic measurements at the Panola
Mountain Research Watershed (Georgia, USA), Hydrol. Process., 15,
1903–1924, https://doi.org/10.1002/hyp.246, 2001.
Capell, R., Tetzlaff, D., Hartley, A. J., and Soulsby, C.: Linking metrics of
hydrological function and transit times to landscape controls in a
heterogeneous mesoscale catchment, Hydrol. Process., 26, 405–420,
https://doi.org/10.1002/hyp.8139, 2012.
Cartwright, I., Cendón, D., Currell, M., and Meredith, K.: A review of
radioactive isotopes and other residence time tracers in understanding
groundwater recharge: Possibilities, challenges, and limitations, J.
Hydrol., 555, 797–811, https://doi.org/10.1016/j.jhydrol.2017.10.053, 2017.
Chaves, J., Neill, C., Germer, S., Neto, S. G., Krusche, A., and Elsenbeer,
H.: Land management impacts on runoff sources in small Amazon watersheds,
Hydrol. Process., 22, 1766–1775, https://doi.org/10.1002/hyp.6803, 2008.
Christophersen, N. and Hooper, R. P.: Multivariate analysis of stream water
chemical data: The use of principal components analysis for the end-member
mixing problem, Water Resour. Res., 28, 99–107, https://doi.org/10.1029/91WR02518,
1992.
Christophersen, N., Neal, C., Hooper, R. P., Vogt, R. D., and Andersen, S.:
Modelling streamwater chemistry as a mixture of soilwater end-members – A
step towards second-generation acidification models, J. Hydrol., 116,
307–320, https://doi.org/10.1016/0022-1694(90)90130-P, 1990.
Cooper, J. D.: Water use of a tea estate from soil moisture measurements, E.
Afr. Agr. Forestry J., 43, 102–121, 1979.
Correa, A., Windhorst, D., Tetzlaff, D., Crespo, P., Célleri, R., Feyen,
J., and Breuer, L.: Temporal dynamics in dominant runoff sources and flow
paths in the Andean Páramo, Water Resour. Res., 53, 5998–6017,
https://doi.org/10.1002/2016WR020187, 2017.
Craig, H.: Isotopic variations in meteoric waters, Science, 133,
1702–1703, https://doi.org/10.1126/science.133.3465.1702, 1961.
Crespo, P., Bücker, A., Feyen, J., Vaché, K. B., Frede, H.-G., and
Breuer, L.: Preliminary evaluation of the runoff processes in a remote
montane cloud forest basin using Mixing Model Analysis and Mean Transit
Time, Hydrol. Process., 26, 3896–3910, https://doi.org/10.1002/hyp.8382, 2012.
de Moraes, J. M., Schuler, A. E., Dunne, T., de O Figueiredo,
R., and Victoria, R. L.:
Water storage and runoff processes in plinthic soils under forest and pasture
in eastern Amazonia, Hydrol. Process., 20, 2509–2526, https://doi.org/10.1002/hyp.6213,
2006.
DeWalle, D. R., Edwards, P. J., Swistock, B. R., Aravena, R., and Drimmie, R.
J.: Seasonal isotope hydrology of three Appalachian forest catchments,
Hydrol. Process., 11, 1895–1906, 1997.
Edwards, K. A. and Blackie, J. R.: Results of the East African Catchment
Experiments 1958–1974, in Tropical Agricultural Hydrology, 163–200,
John Wiley & Sons Ltd., 1981.
Ekirapa, E. A. and Shitakha, F. M.: Semi detailed soil survey of the African
Highland Produce Company farm, Kenya Agricultural Research Institute,
Nairobi, Kenya, 1996.
Fröhlich, H. L., Breuer, L., Vaché, K. B., and Frede, H.-G.:
Inferring the effect of catchment complexity on mesoscale hydrologic
response, Water Resour. Res., 44, W09414, https://doi.org/10.1029/2007WR006207, 2008a.
Fröhlich, H. L., Breuer, L., Frede, H.-G., Huisman, J. A., and Vaché,
K. B.: Water source characterization through spatiotemporal patterns of
major, minor and trace element stream concentrations in a complex, mesoscale
German catchment, Hydrol. Process., 22, 2028–2043, https://doi.org/10.1002/hyp.6804,
2008b.
Geris, J., Tetzlaff, D., McDonnell, J., and Soulsby, C.: The relative role of
soil type and tree cover on water storage and transmission in northern
headwater catchments, Hydrol. Process., 29, 1844–1860,
https://doi.org/10.1002/hyp.10289, 2015.
Germer, S., Neill, C., Krusche, A. V., Neto, S. C. G., and Elsenbeer, H.:
Seasonal and within-event dynamics of rainfall and throughfall chemistry in
an open tropical rainforest in Rondônia, Brazil, Biogeochemistry, 86,
155–174, https://doi.org/10.1007/s10533-007-9152-9, 2007.
Germer, S., Neill, C., Krusche, A. V., and Elsenbeer, H.: Influence of
land-use change on near-surface hydrological processes: Undisturbed forest to
pasture, J. Hydrol., 380, 473–480, https://doi.org/10.1016/j.jhydrol.2009.11.022, 2010.
Goldsmith, G. R., Muñoz-Villers, L. E., Holwerda, F., McDonnell, J. J.,
Asbjornsen, H., and Dawson, T. E.: Stable isotopes reveal linkages among
ecohydrological processes in a seasonally dry tropical montane cloud forest,
Ecohydrology, 5, 779–790, https://doi.org/10.1002/eco.268, 2012.
Heidbüchel, I., Troch, P. A., and Lyon, S. W.: Separating physical and
meteorological controls of variable transit times in zero-order catchments,
Water Resour. Res., 49, 7644–7657, https://doi.org/10.1002/2012WR013149, 2013.
Hooper, R. P.: Diagnostic tools for mixing models of stream water chemistry,
Water Resour. Res., 39, 1055, https://doi.org/10.1029/2002WR001528, 2003.
Hrachowitz, M., Soulsby, C., Tetzlaff, D., Malcolm, I. A., and Schoups, G.:
Gamma distribution models for transit time estimation in catchments: Physical
interpretation of parameters and implications for time-variant transit time
assessment, Water Resour. Res., 46, W10536, https://doi.org/10.1029/2010WR009148, 2010.,
2010.
Hrachowitz, M., Soulsby, C., Tetzlaff, D., and Malcolm, I. A.: Sensitivity of
mean transit time estimates to model conditioning and data availability,
Hydrol. Process., 25, 980–990, https://doi.org/10.1002/hyp.7922, 2011.
ISRIC: Soil and terrain database for Kenya, version 2.0, at scale 1:1
million (KENSOTER), 2007.
Jacobs, S. R., Breuer, L., Butterbach-Bahl, K., Pelster, D. E., and Rufino,
M. C.: Land use affects total dissolved nitrogen and nitrate concentrations
in tropical montane streams in Kenya, Sci. Total Environ., 603–604,
519–532, https://doi.org/10.1016/j.scitotenv.2017.06.100, 2017.
Jacobs, S. R., Weeser, B., Guzha, A. C., Rufino, M. C., Butterbach-Bahl, K.,
Windhorst, D., and Breuer, L.: Using high-resolution data to assess land use
impact on nitrate dynamics in East African tropical montane catchments, Water
Resour. Res., 54, 1812–1830, https://doi.org/10.1002/2017WR021592, 2018.
James, A. L. and Roulet, N. T.: Investigating the applicability of end-member
mixing analysis (EMMA) across scale: A study of eight small, nested
catchments in a temperate forested watershed, Water Resour. Res., 42, W08434,
https://doi.org/10.1029/2005WR004419, 2006.
Jennings, D. J.: Geology of the Molo area, Ministry of Natural Resources,
Geological Survey of Kenya, 1971.
Johnson, M. S., Lehmann, J., Selva, E. C., Abdo, M., Riha, S., and Couto, E.
G.: Organic carbon fluxes within and streamwater exports from headwater
catchments in the southern Amazon, Hydrol. Process., 20, 2599–2614,
https://doi.org/10.1002/hyp.6218, 2006.
Katsuyama, M., Kabeya, N., and Ohte, N.: Elucidation of the relationship
between geographic and time sources of stream water using a tracer approach
in a headwater catchment, Water Resour. Res., 45, W06414,
https://doi.org/10.1029/2008WR007458, 2009.
Kenya Water Towers Agency: Kenya Water Towers status report, Kenya Water
Towers Agency, Nairobi, Kenya, 2015.
Kinyanjui, M. J.: NDVI-based vegetation monitoring in Mau Forest Complex,
Kenya, Afr. J. Ecol., 49, 165–174, https://doi.org/10.1111/j.1365-2028.2010.01251.x,
2011.
Kirchner, J. W.: Aggregation in environmental systems – Part 1: Seasonal
tracer cycles quantify young water fractions, but not mean transit times, in
spatially heterogeneous catchments, Hydrol. Earth Syst. Sci., 20, 279–297,
https://doi.org/10.5194/hess-20-279-2016, 2016a.
Kirchner, J. W.: Aggregation in environmental systems – Part 2: Catchment
mean transit times and young water fractions under hydrologic
nonstationarity, Hydrol. Earth Syst. Sci., 20, 299–328,
https://doi.org/10.5194/hess-20-299-2016, 2016b.
Koutsouris, A. J. and Lyon, S. W.: Advancing understanding in data-limited
conditions: estimating contributions to streamflow across Tanzania's rapidly
developing Kilombero Valley, Hydrolog. Sci. J., 63, 197–209,
https://doi.org/10.1080/02626667.2018.1426857, 2018.
Krhoda, G. O.: The impact of resource utilization on the hydrology of the Mau
Hills Forest in Kenya, Mt. Res. Dev., 8, 193–200, https://doi.org/10.2307/3673447, 1988.
Maloszewski, P. and Zuber, A.: Determining the turnover time of groundwater
systems with the aid of environmental tracers. 1. Models and their
applicability, J. Hydrol., 57, 207–231,
https://doi.org/10.1016/0022-1694(82)90147-0, 1982.
Mango, L. M., Melesse, A. M., McClain, M. E., Gann, D., and Setegn, S. G.:
Land use and climate change impacts on the hydrology of the upper Mara River
Basin, Kenya: results of a modeling study to support better resource
management, Hydrol. Earth Syst. Sci., 15, 2245–2258,
https://doi.org/10.5194/hess-15-2245-2011, 2011.
Mau Earth Observatory: Publications, http://fb09-pasig.umwelt.uni-giessen.de:8050/wiki/publications,
last access: 23 September 2018.
McGuire, K. and McDonnell, J.: Stable isotope tracers in watershed hydrology,
in Stable Isotopes in Ecology and Environmental Science, edited by: Michener,
R. and Lajtha, K., Blackwell Publishing Ltd., 334–374, 2007.
McGuire, K. J. and McDonnell, J. J.: A review and evaluation of catchment
transit time modeling, J. Hydrol., 330, 543–563,
https://doi.org/10.1016/j.jhydrol.2006.04.020, 2006.
Mckenzie, J. M., Mark, B. G., Thompson, L. G., Schotterer, U., and Lin,
P.-N.: A hydrogeochemical survey of Kilimanjaro (Tanzania): implications for
water sources and ages, Hydrogeol. J., 18, 985–995,
https://doi.org/10.1007/s10040-009-0558-4, 2010.
Mosquera, G. M., Lazo, P. X., Célleri, R., Wilcox, B. P., and Crespo, P.:
Runoff from tropical alpine grasslands increases with areal extent of
wetlands, CATENA, 125, 120–128, https://doi.org/10.1016/j.catena.2014.10.010, 2015.
Mosquera, G. M., Célleri, R., Lazo, P. X., Vaché, K. B., Perakis, S.
S., and Crespo, P.: Combined use of isotopic and hydrometric data to
conceptualize ecohydrological processes in a high-elevation tropical
ecosystem, Hydrol. Process., 30, 2930–2947, https://doi.org/10.1002/hyp.10927, 2016a.
Mosquera, G. M., Segura, C., Vaché, K. B., Windhorst, D., Breuer, L., and
Crespo, P.: Insights into the water mean transit time in a high-elevation
tropical ecosystem, Hydrol. Earth Syst. Sci., 20, 2987–3004,
https://doi.org/10.5194/hess-20-2987-2016, 2016b.
Mueller, M. H., Weingartner, R., and Alewell, C.: Importance of vegetation,
topography and flow paths for water transit times of base flow in alpine
headwater catchments, Hydrol. Earth Syst. Sci., 17, 1661–1679,
https://doi.org/10.5194/hess-17-1661-2013, 2013.
Muñoz-Villers, L. E. and McDonnell, J. J.: Runoff generation in a steep,
tropical montane cloud forest catchment on permeable volcanic substrate,
Water Resour. Res., 48, W09528, https://doi.org/10.1029/2011WR011316, 2012.
Muñoz-Villers, L. E. and McDonnell, J. J.: Land use change effects on
runoff generation in a humid tropical montane cloud forest region, Hydrol.
Earth Syst. Sci., 17, 3543–3560, https://doi.org/10.5194/hess-17-3543-2013,
2013.
Muñoz-Villers, L. E., Geissert, D. R., Holwerda, F., and McDonnell, J.
J.: Factors influencing stream baseflow transit times in tropical montane
watersheds, Hydrol. Earth Syst. Sci., 20, 1621–1635,
https://doi.org/10.5194/hess-20-1621-2016, 2016.
Mwangi, H. M., Julich, S., Patil, S. D., McDonald, M. A., and Feger, K.-H.:
Relative contribution of land use change and climate variability on discharge
of upper Mara River, Kenya, J. Hydrol.-Regional Studies, 5, 244–260,
https://doi.org/10.1016/j.ejrh.2015.12.059, 2016.
Nash, J. E. and Sutcliffe, J. V.: River flow forecasting through conceptual
models part I – A discussion of principles, J. Hydrol., 10, 282–290,
https://doi.org/10.1016/0022-1694(70)90255-6, 1970.
Neill, C., Chaves, J. E., Biggs, T., Deegan, L. A., Elsenbeer, H.,
Figueiredo, R. O., Germer, S., Johnson, M. S., Lehmann, J., Markewitz, D.,
and Piccolo, M. C.: Runoff sources and land cover change in the Amazon: An
end-member mixing analysis from small watersheds, Biogeochemistry, 105,
7–18, https://doi.org/10.1007/s10533-011-9597-8, 2011.
Otte, I., Detsch, F., Gütlein, A., Scholl, M., Kiese, R., Appelhans, T.
and Nauss, T.: Seasonality of stable isotope composition of atmospheric water
input at the southern slopes of Mt. Kilimanjaro, Tanzania, Hydrol. Process.,
31, 3932–3947, https://doi.org/10.1002/hyp.11311, 2017.
Owuor, S. O., Butterbach-Bahl, K., Guzha, A. C., Jacobs, S., Merbold, L.,
Rufino, M. C., Pelster, D., Díaz-Pinés, E., and Breuer, L.:
Conversion of natural forest results in a significant degradation of soil
hydraulic properties in the highlands of Kenya, Soil Till. Res., 176, 36–44,
https://doi.org/10.1016/j.still.2017.10.003, 2018.
Prechsl, U. E., Gilgen, A. K., Kahmen, A., and Buchmann, N.: Reliability and
quality of water isotope data collected with a low-budget rain collector,
Rapid Commun. Mass Sp., 28, 879–885, https://doi.org/10.1002/rcm.6852, 2014.
Roa-García, M. C. and Weiler, M.: Integrated response and transit time
distributions of watersheds by combining hydrograph separation and long-term
transit time modeling, Hydrol. Earth Syst. Sci., 14, 1537–1549,
https://doi.org/10.5194/hess-14-1537-2010, 2010.
Rodgers, P., Soulsby, C., Waldron, S., and Tetzlaff, D.: Using stable isotope
tracers to assess hydrological flow paths, residence times and landscape
influences in a nested mesoscale catchment, Hydrol. Earth Syst. Sci., 9,
139–155, https://doi.org/10.5194/hess-9-139-2005, 2005.
Saunders, T. J., McClain, M. E., and Llerena, C. A.: The biogeochemistry of
dissolved nitrogen, phosphorus, and organic carbon along terrestrial-aquatic
flowpaths of a montane headwater catchment in the Peruvian Amazon, Hydrol.
Process., 20, 2549–2562, https://doi.org/10.1002/hyp.6215, 2006.
Soderberg, K., Good, S. P., O'Connor, M., Wang, L., Ryan, K., and Caylor, K.
K.: Using atmospheric trajectories to model the isotopic composition of
rainfall in central Kenya, Ecosphere, 4, 33, https://doi.org/10.1890/ES12-00160.1, 2013.
Soulsby, C., Rodgers, P., Smart, R., Dawson, J., and Dunn, S.: A tracer-based
assessment of hydrological pathways at different spatial scales in a
mesoscale Scottish catchment, Hydrol. Process., 17, 759–777,
https://doi.org/10.1002/hyp.1163, 2003.
Soulsby, C., Tetzlaff, D., Rodgers, P., Dunn, S., and Waldron, S.: Runoff
processes, stream water residence times and controlling landscape
characteristics in a mesoscale catchment: An initial evaluation, J. Hydrol.,
325, 197–221, https://doi.org/10.1016/j.jhydrol.2005.10.024, 2006.
Stewart, M. K. and Morgenstern, U.: Importance of tritium-based transit times
in hydrological systems, Wiley Interdisciplinary Reviews: Water, 3, 145–154,
https://doi.org/10.1002/wat2.1134, 2016.
Stewart, M. K., Morgenstern, U., and McDonnell, J. J.: Truncation of stream
residence time: how the use of stable isotopes has skewed our concept of
streamwater age and origin, Hydrol. Process., 24, 1646–1659,
https://doi.org/10.1002/hyp.7576, 2010.
Timbe, E., Windhorst, D., Crespo, P., Frede, H.-G., Feyen, J., and Breuer,
L.: Understanding uncertainties when inferring mean transit times of water
trough tracer-based lumped-parameter models in Andean tropical montane cloud
forest catchments, Hydrol. Earth Syst. Sci., 18, 1503–1523,
https://doi.org/10.5194/hess-18-1503-2014, 2014.
von Freyberg, J., Radny, D., Gall, H. E., and Schirmer, M.: Implications of
hydrologic connectivity between hillslopes and riparian zones on streamflow
composition, J. Contam. Hydrol., 169, 62–74,
https://doi.org/10.1016/j.jconhyd.2014.07.005, 2014.
von Freyberg, J., Allen, S. T., Seeger, S., Weiler, M., and Kirchner, J. W.:
Sensitivity of young water fractions to hydro-climatic forcing and landscape
properties across 22 Swiss catchments, Hydrol. Earth Syst. Sci., 22,
3841–3861, https://doi.org/10.5194/hess-22-3841-2018, 2018.
Windhorst, D., Waltz, T., Timbe, E., Frede, H.-G., and Breuer, L.: Impact of
elevation and weather patterns on the isotopic composition of precipitation
in a tropical montane rainforest, Hydrol. Earth Syst. Sci., 17, 409–419,
https://doi.org/10.5194/hess-17-409-2013, 2013.
Windhorst, D., Kraft, P., Timbe, E., Frede, H.-G., and Breuer, L.: Stable
water isotope tracing through hydrological models for disentangling runoff
generation processes at the hillslope scale, Hydrol. Earth Syst. Sci., 18,
4113–4127, https://doi.org/10.5194/hess-18-4113-2014, 2014.
Short summary
This study investigated how land use affects stream water sources and flow paths in an East African tropical montane area. Rainfall was identified as an important stream water source in the forest and smallholder agriculture sub-catchments, while springs were more important in the commercial tea plantation sub-catchment. However, 15 % or less of the stream water consisted of water with an age of less than 3 months, indicating that groundwater plays an important role in all land use types.
This study investigated how land use affects stream water sources and flow paths in an East...
