Articles | Volume 26, issue 19
https://doi.org/10.5194/hess-26-5051-2022
© Author(s) 2022. 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-26-5051-2022
© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
11 Oct 2022
Research article |
| 11 Oct 2022
| 11 Oct 2022
Effect of topographic slope on the export of nitrate in humid catchments: a 3D model study
State Key Laboratory of Hydrology-Water Resources and Hydraulic
Engineering, Hohai University, Nanjing, China
Qiaoyu Wang
State Key Laboratory of Hydrology-Water Resources and Hydraulic
Engineering, Hohai University, Nanjing, China
Ingo Heidbüchel
Department of
Hydrogeology, UFZ – Helmholtz-Centre for Environmental Research GmbH, Leipzig, Germany
Hydrologic Modeling Unit, Bayreuth Center of Ecology and Environmental
Research (BayCEER), University of Bayreuth, Bayreuth, Germany
Chunhui Lu
CORRESPONDING AUTHOR
State Key Laboratory of Hydrology-Water Resources and Hydraulic
Engineering, Hohai University, Nanjing, China
Yueqing Xie
School of Earth Sciences and Engineering, University of Nanjing,
Nanjing, China
Andreas Musolff
Department of
Hydrogeology, UFZ – Helmholtz-Centre for Environmental Research GmbH, Leipzig, Germany
Jan H. Fleckenstein
Department of
Hydrogeology, UFZ – Helmholtz-Centre for Environmental Research GmbH, Leipzig, Germany
Hydrologic Modeling Unit, Bayreuth Center of Ecology and Environmental
Research (BayCEER), University of Bayreuth, Bayreuth, Germany
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Zhongbo Yu, Chunhui Lu, Jianyuan Cai, Dazheng Yu, Gil Mahe, Anil Mishra, Christophe Cudennec, Henny A. J. Van Lanen, Didier Orange, and Abou Amani
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Short summary
We assessed the effect of catchment topographic slopes on the nitrate export dynamics in terms of the nitrogen mass fluxes and concentration level using a coupled surface–subsurface model. We found that flatter landscapes tend to retain more nitrogen mass in the soil and export less nitrogen mass to the stream, explained by the reduced leaching and increased potential of degradation in flat landscapes. We emphasized that stream water quality is potentially less vulnerable in flatter landscapes.
We assessed the effect of catchment topographic slopes on the nitrate export dynamics in terms...
