ESTONIAN ACADEMY
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Estonian Journal of Ecology
Spirogyra africana (Fritsch) Czurda bloom and associated fishing impairment in a tropical freshwater lagoon; pp. 18–26
PDF | doi: 10.3176/eco.2009.1.02

Authors
Ikenna Charles Onyema, Babatunde Eniola Emmanuel
Abstract

Greenish and slimy materials clogging fishing nets in parts of the Lekki Lagoon, Nigeria, were investigated in relation to water quality characteristics. Blooms were caused by the filamentous green alga Spirogyra africana (Fritsch) Czurda, which was the sole causative organism. Evaporative concentration leading to higher nutrients levels, increased light availability, hydrological stability, and absence of aquatic macrophytes covering the water surface are factors that probably encouraged the bloom. Reduced floodwater inputs and improved insolation are also possible implicated causative factors. The bloom condition was only recorded in the dry season and was absent during the rains.

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