Hydro biology some of its formation of the Volta tributaries before of the Volta Lake
1968
Biswas, S., Volta Basin Research Project, University of Ghana
Observations made from September 1963 to May 1964 showed that the Volta River was relatively poor in phytoplankton until January 1964. These organisms appeared in appreciable numbers from January 1964 and reached their peaks between March and May 1964. This period of algal abundance resulted in a decrease in the dissolved nutrients and an increase in the pH of water. Diatoms such as Melosira and Synedra were abundant earlier,and a blue-green alga, Anabaena, later. The upper reaches of the river were richer in both phytoplankton and total alkalinity than the lower reaches. Higher alkalinity thus seemed to favour phytoplankton productivity. A blue-green alga, Arthrospira, occurred abundantly at Yeji. It was also recorded as far down stream as Kpandu but not at Ajena.The reason for this is not clear. The tributaries were relatively poor in phytoplankton and rich in dissolved nutrients. Phytoplankton in these waters was usually in the form of diatoms. The seasonal pattern. of phytoplankton abundance was irregular in the smaller tributaries while it was somewhat similar to that of the Volta River in the larger tributaries. An abrupt increase in phytoplankton occurred as far upstream as Kpandu following the closure of the dam. Some striking changes in the dissolved oxygen also took place as a result of this. During the transition of the Volta River in to a lake the phytoplankton consisted mainly of Anabaena.
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