Monitoring water flux dynamics between the Congo River main-stem and Cuvette Centrale wetlands

The water fluxes between a river and its floodplain are a key part of the water cycle and sustain special ecosystems adapted to these regular cycles. Despite being the world’s second largest river by flow, we still do not know with any certainty or detail what these fluxes are for the Congo River and the Cuvette Centrale wetland at its centre (Alsdorf et al. 2016).

We do know that the Cuvette Centrale supports expansive wetland forests and vast peatlands, the health of which are tied strongly to the water cycle and its dynamics (Dargie et al. 2017). The aim of this PhD will be to quantify these important fluxes and what governs their variation and direction, to better understand the fluvial connection between the main river channel and the Cuvette Centrale wetlands and their role in supporting this important ecosystem.

The project will require the use of a range of hydrological methods and data. There will be fieldwork involved in the DRC, installing in-situ hydrological equipment to collect long-term data of hydrology variables such as rainfall, water levels and river flow. The fieldwork will also involve the use of Acoustic Doppler Current Profiler (ADCP), sonar and other during fieldwork instruments to measure parameters at other locations, as well as for calibrating the long-term monitoring equipment.

Due to the vast scale of the river, it will be necessary to augment the monitoring data with analysis and study of a range of remote sensing data to: (i) identify the best locations for in-situ measurements, and (ii) scale the local measurements to draw implications for a much larger spatial area. Finally, if data is sufficient, it may be possible to build on some existing 2D hydrodynamic modelling to better quantify fluxes temporally.

This PhD will be undertaken alongside two other PhDs observing hydrology in the Congo Basin (and MSc projects). These PhDs are a key component of the Hydrology and Freshwater Observatory in the CBSI Science and Capacity Plan project and will set the path for the future of hydrology research in the Congo Basin.

Coordination is essential to ensure similar methods, efficient use of resources, combined field logistics and sharing of data and findings. Alongside the Hydrology and Freshwater Observatory, it is envisaged that this PhD will need to coordinate with other PhDs in other observatories as well, particularly the observatories covering climate and vegetation.

The PhD will enhance the consolidation of the Congo Basin Catchment Information System (CB-CIS, cbcis.info) through regular provision of in-situ data quality, remote sensing and modelling results. CB-CIS is part of the global hydrology and freshwater observatory for the Congo basin.

The results of the PhD will be an important input to other research work in the project such as those of biodiversity and socio-ecology. A key objective is to assess how changes in water surface elevations and the connectivity of rivers to wetlands influences the central Congo peatlands, in order to understand how any changes may affect fishing in the peatlands, a major livelihood activity, and how any changes in these flows may affect the globally significant storage of carbon in the water-logged peat soil.

The Hydrology and Freshwater Observatory will build on and extend the pioneering work of the Congo River users Hydraulics and Morphology project funded by the Royal Society (2016- 2022). The CRuHM project established fieldwork methodologies for measuring hydrology in this challenging environment and therefore your PhD supervisors have personal experience of working in this context (Bates et al. 2024, Tshimanga et al. 2022).

You will be encouraged to develop and strengthen collaborations with other CBSI students and researchers working. You will be supported to publish your work in leading academic journals and communicate your results as widely as possible, including to policy makers.

This strong experienced supervision team and well-funded research project will provide a fantastic opportunity to develop your research skills and make a unique contribution to scientific discovery and sustainability of the Congo Basin.