Thesis Code: T4

Exploring Dam-Induced Impacts on River Biodiversity across Basin and Continental Scales

Short description:

In recent decades, global water resources are facing increasing pressure due to growing demands for food and energy, improved living standards, and complex regional water governance. These factors have led to the rapid development of several dams worldwide, provoking cumulative impacts on both the river ecosystems and the communities reliant on them.

The presence of dams causes fragmentation of the river network and controls the water discharges, severely altering the river’s hydrological regime and the sediment and nutrients transport processes. River fragmentation is inevitably translated into a reduced migration of freshwater fish species and into a loss of ecosystem habitats, disrupting the life cycle of river species and causing an overall decrease in biodiversity and fish biomass for local fisheries. The assessment of these impacts through appropriate habitat suitability maps and biodiversity indicators, and their integration into energy-water management models can lead to a better understanding of trade-offs between the production of clean energy through hydropower plants and the adverse effects they generate on local ecosystems (1) (2).

The proposed thesis topic can be expanded to involve two MSc students, exploring its application in two distinct case studies: the African continent or the Mekong River basin. The objective of these theses is to assess the impact on riverine ecosystems arising from either the planning of dams (African continent) (3) or the operation and management of dams (Mekong River basin) (4). Due to the distinct goals of each thesis, various modelling frameworks will be employed, encompassing two or more of the following: a large-scale hydrological-water management model, a sediment transport model, a large-scale energy system model, and a biodiversity analysis model. While the Mekong River thesis will focus on evaluating the impact of different optimal dam operation strategies, the African thesis will explore the impact of cost-optimal dams planning under different socio-economic and climatic scenarios. 

To achieve these goals, we expect the student to carry out the following activities: 

  • Literature review: reviewing state-of-the-art models that describe the loss of ecosystem habitats and biodiversity in relation to dam construction and operation. This involves understanding and identifying the most suitable variables to be used as inputs in a Species Distribution Model.
  • Data elaboration: manipulating the energy-hydrological model results to extrapolate the variables required for the Species Distribution Model in order to perform a biodiversity analysis for the considered case study.
  • Impact evaluation and results interpretation: quantifying the loss in ecosystem habitats under different configurations of dam location and management, with the aim of inferring relevant conclusions.

References

  1. Barbarossa, Valerio, Rafael J. P. Schmitt, Mark A. J. Huijbregts, Christiane Zarfl, Henry King, and Aafke M. Schipper. ‘Impacts of Current and Future Large Dams on the Geographic Range Connectivity of Freshwater Fish Worldwide’. Proceedings of the National Academy of Sciences 117, no. 7 (18 February 2020): 3648–55. https://doi.org/10.1073/pnas.1912776117.
  2. Marlene Schürz, Afroditi Grigoropoulou, Jaime García Márquez, Yusdiel Torres-Cambas, Thomas Tomiczek, Mathieu Floury, Vanessa Bremerich, Christoph Schürz, Giuseppe Amatulli, Hans-Peter Grossart, and Sami Domisch. ‘hydrographr: An R package for scalable hydrographic data processing’. Methods in Ecology and Evolution 14, no. 12 (12 September 2023): 2953–2963. DOI: 10.1111/2041-210X.14226
  3. Carlino, Angelo, Matthias Wildemeersch, Celray James Chawanda, Matteo Giuliani, Sebastian Sterl, Wim Thiery, Ann Van Griensven, and Andrea Castelletti. ‘Declining Cost of Renewables and Climate Change Curb the Need for African Hydropower Expansion’. Science 381, no. 6658 (11 August 2023): eadf5848. https://doi.org/10.1126/science.adf5848.
  4. Stefano Galelli, Thanh Duc Dang, Jia Yi Ng, A.F.M Kamal Chowdhury, and Mauricio E. Arias. ‘Opportunities to curb hydrological alterations via dam re-operation in the Mekong’. Nature Sustainability 5, (31 October 2022): 1058-1069. 

Relevant courses and knowledge:

Natural Resources Management

Number of students:

2

Requisites:

The student should be comfortable with data handling and machine learning tools. Proficient coding skills are strongly recommended.