Abstract:

Zooplankton play a substantial role in the ecology of aquatic ecosystems and are usually used as bioindicators to assess their health. This study aims to assess the structure and diversity of Zooplankton community in Taabo reservoir. Zooplankton were sampled at five sites along a transect of seven kilometers every 45 days from November 2017 to October 2018 using a net of 20µm mesh size. A total of 77 taxa belonging to four groups (59 rotifera, ten cladocera, five copepoda and three otherzooplankton). High diversity of zooplankton (more than 87%)was reported in the littoral areas (S1 and S5).The proportion of very frequent taxa are the most numerous at all the sampling sites, and Sorensen similarity indexes between these sites are higher than 80%. Zooplankton abundance was higher during the dry season at all sites. Zooplankton community of Taabo reservoir was qualitatively (76.6 % of the taxonomic richness) and quantitatively (more than 68.35% of the relative abundance) dominated by rotifers group.Shannon-Weaver diversity and Pielou Evenness indices were lower in long rainy season than the other seasons. The RDA analysis shows that the abundances of zooplankton taxa such as Mesocyclops sp., Thermocyclops sp., Ceriodaphniacornulata and Diaphanosomaexcisumwere positively affected by conductivity, water depth, pH, TP, and TN. However, water transparency and temperature had positively influenced the abundances of zooplankton taxa such as Anuraeopsisfissa, Brachionusangularis, Brachionuscaudatus, Brachionusfalcatus, KeratellaLenzi, Keratellatropica, Hexathraintermediaire, Epiphanesmacrourus, Filiniaopoliensis, Lecaneleontine, and Nauplii.Zooplankton communitywas affected by anthropogenicdisturbances.

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