Diversity, abundance and seasonal dynamic of Zooplankton community in a South-Saharan reservoir (Burkina Faso)

Abstract

From May 2004 to April 2005, the zooplankton of the Loumbila reservoir was subject to a 14 days periodicity follow-up. This study attempt to describe the diversity, abundance and seasonal dynamic of zooplankton community in a south-saharian reservoir. Plankton community was sampled with horizontal tows of a plankton net of 100 μm mesh size. The samples analysis permitted to identify 7 species of Cladocera and 2 species of the Copepoda. The overall Rotifers observed belong to 14 genera. The Cochran's Q-test together with various methods of variance analyses and the Redundancy Analysis (RDA) allowed to highlight the seasonal dynamics of zooplankton settlement. The most significant factor in this dynamics is water movement i.e., water gain or loss in the reservoir. This factor evolves together with some physicochemical parameters favourable to plankton development and simultaneously opposes some other unfavourable factors such as high conductivity. Crustaceans are more sensitive to the season impacts than Rotifers. Besides this seasonal variability the zooplankton community of Loumbila reservoir also shows variability according to depth. © 2007 Asian Network for Scientific Information.