Mapping groundwater vulnerability at the pan-African scale

Ouedraogo, Issoufou
(2017)

Files

PhD_Issoufou_Ouedraogo2017.pdf
  • Open Access
  • Adobe PDF
  • 8.61 MB
Download

Details

Authors
  • Ouedraogo, IssoufouUCLouvain
    author
Supervisors
Vanclooster , Marnik
Abstract
Assessing groundwater vulnerability is key to monitor the implementation of the UN SDG for water. We therefore studied in this thesis groundwater vulnerability for pollution at the African scale. The first main objective was to map groundwater vulnerability to pollution at the African scale by applying DRASTIC index. Best available datasets for land use, soil, topography, geology and hydrogeology were collected from different sources. We compiled these data into a 15x15 km2 resolution geodatabase for the continent and used to build the variables of the DRASTIC index. This resulted in the first pan-African groundwater vulnerability and pollution risk map. The map shows that areas under very high and high pollution risk are mainly characterised by shallow groundwater. In second main objective we developed a statistical model to identify environmental variables that explain pollution in groundwater at the African scale. Through a meta-analysis, we compiled a literature database of nitrate contamination. Two statistical models were used to link nitrate and environmental variables and demonstrated the unambiguous link between population density and nitrate pollution. We recalibrated and validated these statistical models using regional datasets of nitrate measured in groundwater. In last main objective, we integrated the time dynamics in the DRASTIC index, focussing on the time dynamics of population density and climate as drivers of groundwater pollution. This approach demonstrated that the groundwater vulnerability to pollution across Africa varies indeed considerably in time, in particularly in densely populated areas in West Africa, the Nile delta, and urbanised regions in East and southern Africa.
Affiliations

Citations

  • APA
  • Chicago
  • FWB

Ouedraogo, I. (2017). Mapping groundwater vulnerability at the pan-African scale. https://hdl.handle.net/2078.5/43574