Relationship between physicochemical parameters and the abundance of zooplankton in Lake Mweru-Wantipa, Zambia

Abstract

Abstract. Anamunda A, Lamtane HA. 2022. Relationship between physicochemical parameters and the abundance of zooplankton in Lake Mweru-Wantipa, Zambia. Intl J Bonorowo Wetlands 12: 33-40. This study aimed to assess the abundance of zooplankton and their relationship with physicochemical parameters within Lake Mweru-Wantipa, Zambia. A National Park borders the lake on one side and settlements on the other, so four sampling stations were selected, two on each side of the lake. Five physicochemical parameters, including temperature, turbidity, salinity, pH, and dissolved oxygen, were measured monthly using portable instruments concurrently with a collection of duplet zooplankton samples at each sampling point at depths between 0.1m and 0.5m. All physicochemical parameters were significantly different between the two sites (p<0.05) apart from temperature and pH. A total of 13 genera of zooplankton were identified, belonging to four groups, namely, rotifers, cladoceran, copepods, and ostracods. The cladoceran had the highest number of species (6), followed by copepods (4) in both sites. However, the copepods had the largest contribution in abundance in both sites. The diversity was high in settlement areas, but the National Park had higher species richness. There was a significant difference in species diversity between the two sites (t=3.96; p=0.001). The most abundant group was the cyclopoid on both sides of the lake, followed by the Moina on the settlement site and the Daphnia sp. on the National Park site. The densities of Molina, Simocephalus, Ceriodaphinia, and Cypris were significantly different between the two sites (p<0.05). Except for copepods, all groups were significantly different between the two sites (p<0.05). Generally, the total zooplankton density was not significantly different between the two sites (t=0.73; p=0.06). The results showed that the zooplankton abundance was influenced by turbidity in settlement areas and pH in National park areas.