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Ecological Devastation in Lake Victoria: Part A: Thermal Structure and Anoxia

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DOI: 10.4236/oje.2015.57023    2,650 Downloads   3,185 Views   Citations
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ABSTRACT

Lake Victoria is the second (excl. Caspian Sea) largest lake in the world by surface area and 7th by Volume. The lake and catchment territories are shared between three countries, Kenya, Uganda and Tanzania. A research was carried out during 1990-1992 exploring the changes of the thermo-chemical structure occurred after the invasion of Nile Perch. Results of changes of physico-chemical (Temperature, DO and pH) conditions are summarized in this paper. The anoxic conditions by space and time were enhanced. Enhancement of pollutant supply from anthropogenic developments of terrestrial sources and atmospheric dust deposition accompanied by the deleterious effects of the Nile Perch invasion caused enhancement of anoxia in the lake in space and time. The combination of bottom-up nutrient supply and strong mixing conditions, expressed as low RTR values accelerate phytoplankton growth rate and production. The surplus of organic matter originated from algal biomass, enhanced anoxia.

Conflicts of Interest

The authors declare no conflicts of interest.

Cite this paper

Gophen, M. (2015) Ecological Devastation in Lake Victoria: Part A: Thermal Structure and Anoxia. Open Journal of Ecology, 5, 287-298. doi: 10.4236/oje.2015.57023.

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