Fluvial Processes 2
Fluvial processes result in erosion, transportation and deposition on the river bed. Floods are common in humid regions due increasing precipitation and usually have devastating effects leading to soil erosion and siltation. This can eventually result in desertification, particularly in areas where there has been changes in the landscape due to human activities such as deforestation and poor agricultural practices. Excessive erosion of the river beds and embankments by floods might change the nature course of the river and failure of bridge structures. A further water level rises in water bodies and energeis associated with water circulation can result in shore erosion as additional source of sediment and organic matter input.
The fluvial systems are closely linked to the slope, and the response to a change in the climate may be very rapid or slow. A flood may occur almost instantaneously depending on the Read more (PDF 20B) about factors affecting floods.
The formation of features such as ox bow lakes can be accelerated due to increasing rainfall which naturally results in more energy for the channel.
It also increases the sedimentation in river channels, lakes and reservoirs. This can have negative impact on the biodiversity in these aquatic and marine environments. Furthermore, the sedimentation of river channels, lakes and reservoirs can also cause flooding. These accelerated soil erosion rates associated with climate change such as increase in rainfall are also linked to land use changes by human beings, as has been established in areas where deforestation is now a problem of increasing human populations. The common geomorphic processes of rainsplash, sheet erosion, rill erosion and gulley erosion do become accelerated in conditions of increased rainfall, especially in areas of steep slopes and low ground cover. Extreme events such as flooding, drought such as in Eastern Africa can be attributed to changes in climate. See the case study from Lake Victoria Basin in Kenya of river bank erosion and channel change.