Dry season abundance, distribution and diversity of freshwater plankton in lakes Babati and Burunge, Northern Tanzania

Abstract

This study investigated the abundance, distribution and diversity of planktonic organisms in Babati and Burunge lakes in Manyara region. Field sampling of phytoplankton and zooplankton were conducted in July and August 2022 followed by laboratory analysis. Phytoplankton communities were dominated by Bacillariophyceae (35.90%, 35.40%) and Chlorophyceae (32.10%, 24.00%) for Babati and Burunge lakes respectively. Among the zooplankton, Cladoceridae (37.70%) was most abundant in Lake Babati, while Cyclopidae (36.60%) was most abundant in Lake Burunge. Lake Babati had higher plankton species richness (S = 50) compared to Lake Burunge (S = 45). A slightly higher phytoplankton diversity, H = 3.14 was observed in Lake Burunge compared to Lake Babati, H = 3.04. Lake Babati had slightly higher zooplankton diversity, H = 2.61 compared to Lake Burunge, H = 2.30). Evenness (E) ranged 0.56 – 0.70 for phytoplankton and 0.77 – 0.80 for zooplankton indicating a moderate healthier and more diverse aquatic ecosystem. Phytoplankton and zooplankton typically exhibited a clear inverse correlation during various time intervals in different lakes. Sustainable management practices, protection of water quality and habitat preservation are needed in conservation of planktonic communities for maintaining the ecosystem health.