EGU23-7565, updated on 29 Dec 2023
EGU General Assembly 2023
© Author(s) 2023. This work is distributed under
the Creative Commons Attribution 4.0 License.

Recent advancement in water quality indicators for eutrophication in global freshwater lakes

Keerthana Suresh1,2, Ting Tang1, Michelle T.H. van Vliet2, Marc F.P. Bierkens2,4, Maryna Strokal3, Florian Sorger-Domenigg1, and Yoshihide Wada1,2,5
Keerthana Suresh et al.
  • 1International Institute of Applied Systems Analysis (IIASA), Laxenburg, Austria
  • 2Department of Physical Geography , Utrecht University ,Utrecht, The Netherlands
  • 3Environmental Systems Analysis Group, Wageningen University, Wageningen, The Netherlands
  • 4Deltares, Unit Subsurface and Groundwater Systems, Utrecht, The Netherlands
  • 5Climate and Livability, Biological and Environmental Science and Engineering Division, Kind Abdullah University of Science and Technology, Thuwal, Saudi Arabia

Excessive nutrient (nitrogen and phosphorus) loadings to freshwater lakes cause eutrophication, which is a global water quality issue. Anthropogenic activities in lake basins emit nutrients, either as point- (e.g., sewage) or diffuse sources (e.g., agricultural runoff). Their typical impacts on lake water quality include the occurrence of harmful algal blooms, hypoxia and fish kills. These impacts are likely to worsen due to climate change, population growth and economic development. The response of lakes to a change in nutrient inputs depends on their interactions with the climate, land-use, hydrology and socio-economic conditions of a lake basin. These feedback mechanisms, however, are not often included in the eutrophication assessments for lakes. In this study, we present a new causal network of the drivers-pressure-state-impact-response (DPSIR) framework using a total of 58 sub-indicators to characterize all the DPSIR elements and systematically conceptualize the complex interactions of nutrients in freshwater lake basins. The network provides a holistic perspective on nutrient dynamics of multiple indicators and their interactive effects on water quality in lake basins, which is key to improving water quality management. Furthermore, we disentangle the complex eutrophication mechanisms using drivers and pressures, that represent different sources and nutrient pathways. The study highlights coupling of lake systems in water quality modeling frameworks and assessments which is required to understand its impact on water quality from human activities in the basin. The drivers and pressures can be used as proxies to provide meaningful information on nutrient emissions and biogeochemical pathways, that can fill the gap in water quality monitoring data, especially in data scarce regions such as Asia and Africa. These indicators can be used to set realistic water quality targets, and are, therefore, beneficial in long-term policy making and sustainable water quality management.

How to cite: Suresh, K., Tang, T., T.H. van Vliet, M., F.P. Bierkens, M., Strokal, M., Sorger-Domenigg, F., and Wada, Y.: Recent advancement in water quality indicators for eutrophication in global freshwater lakes, EGU General Assembly 2023, Vienna, Austria, 23–28 Apr 2023, EGU23-7565,, 2023.