By Dr Rick Leah, SWIMMER, Nicholson Building
Tropical rivers are very different in many ways from temperate rivers. A brief introduction will be given the major factors structuring their ecosystems together with the implications for their management (the word tropical will be used fairly loosely as a number of rivers in hotter parts of the globe will be referred to as examples). Most large river systems have undergone major change due to human impact, not the least of which are the impacts caused by the building of large dams.
Brief Notes for the
section on the characteristics of major river systems in the hotter
parts of the world are
available here
Brief Notes on the
impact of impoundments on some major tropical river systems are
available here
The Niger (WWF Living waters Campaign) River is a typical river of the Savanna region of Africa, which originally demonstrated the classical features associated with the very variable rivers in the tropics. However, the river Niger was dammed by the Kainji dam (closed in 1968) and this has caused many of the typical problems of impoundment.
The Orinoco (WWF Living waters Campaign) river is a much less well known (than the Amazon) South American tropical river (which unusually, is partly connected to the latter river via a captured tributary).
The Yangste (WWF Living waters Campaign) river in China is famous at the moment because of the Three Gorges Dam project (see notes on impacts of impoundments and the article in wikipedia) but is also the subject of some new agreements to protect and improve its areas of wildlife habitat. One unresolved issue that may find an answer in the near future is the impact on seismicity in the area as the lake fills with a massive weight of water. Increased numbers of earthquakes are already being noted (Oct 2006)
(WWF Links are to archive copies as the WWW is constantly changing)
Page Author: Dr Rick T Leah, Univ of L'pool - Contents last reviewed 05/01/2007