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This blog will cover the effects that environmental change will have on hydrological systems throughout Africa. Africa is an incredibly diverse continent and the climate systems operating throughout differ considerably. You just need to look at the differences in landscape between Egypt and the Demographic Republic of the Congo to understand how considerable the differences in climate are. These differences are the result of the ITCZ moving poleward north and south of the equator, bringing extreme rainfall with it. The heterogeneous nature of Africa means that environmental change will affect different regions in different ways.

Environmental change can come in a number of forms, but the ones that will be discussed on this blog are climate change and land use change. Both climate change and land-use change can cause an increase or decrease in river runoff. deWit and Stankiewicz (2006) carried out a study where they assessed the changes that a 10% reduction in precipitation would have on drainage. In regions that experienced precipitation of over 1000 mm/yr, it was estimated that drainage would reduce by 17%, however in regions receiving 500 mm/yr of rainfall, drainage was expected to reduce by 50%, showing the disparity in the relationship between environmental change and water across Africa. In a study on land-use change in West Africa, it was found that deforestation and overgrazing had a significant effect on increasing runoff, but concluded by saying that any positive effects from an increase in runoff would be outweighed by the ecological damages that decreased vegetation coverage would consist of.

These two examples should give you a brief insight towards the complexity surrounding environmental change and water in Africa. As complex as this relationship may be, an understanding of it is vital if to aid government and administrative bodies in making quantitative based management decisions for the future provision of water resources.