Articles | Volume 29, issue 7
https://doi.org/10.5194/hess-29-1829-2025
© Author(s) 2025. 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-29-1829-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Multivariate and long-term time series analysis to assess the effect of nitrogen management policy on groundwater quality in Wallonia, BE
Elise Verstraeten
Earth and Life Institute – Environmental Sciences, Université catholique de Louvain, Louvain-la-Neuve, 1348, Belgium
Earth and Life Institute – Environmental Sciences, Université catholique de Louvain, Louvain-la-Neuve, 1348, Belgium
Louise Collier
Société Wallonne des Eaux, Verviers, 4800, Belgium
Marnik Vanclooster
Earth and Life Institute – Environmental Sciences, Université catholique de Louvain, Louvain-la-Neuve, 1348, Belgium
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Short summary
This study takes a data-driven approach to evaluate long-term groundwater nitrate concentration trends in Wallonia, Belgium, over ~20 years following the implementation of regional nitrogen management policies. Results highlight a persistently negative impact of agricultural land use, the importance of sustained policies and long-term monitoring to mitigate nitrogen legacy effects, and the need for improved datasets to better capture controlling factors.
This study takes a data-driven approach to evaluate long-term groundwater nitrate concentration...