Distribution of Zooplankton Community in the River Nile at Esna Barrages, Egypt in relation to some ecological factors

Seasonal variations in the abundance and diversity of zooplankton community inhabiting River Nile and its branches at Qena governorate, Upper Egypt.

“…Variations in both physicochemical properties, as well as biotic factors such as feeding ecology and predator pressure, have a significant impact on the distribution and diversity of zooplankton (Egborge, 1994). Previous studies indicated that physicochemical conditions of the aquatic environments can cause changes in the qualitative and quantitative composition of zooplankton and influence their densities (Lin et al, 2003;Rita et al, 2005and Obuid-allah et al, 2019, 2020. Nevertheless, not much is known on all the factors that control the seasonal variations of zooplankton abundance and diversity in freshwater ecosystems thus, it should be a concern to new and intending researchers for further studies.…”

Physicochemical Parameters of River Water and their Relation to Zooplankton: A Review

“…Water temperature coincided with air temperature, Ali et al [9] and Obuid-Allah et al [10] recorded water temperatures in the Nile River were conformable to the Egyptian climate, the minimum degrees were recorded in winter months and maximum degrees were in summer. In Tigris River also water temperatures increased in summer and decreased in winter [11,12,13].…”

Effect of Environmental Variables on Zooplankton in Various Habitats of the Nile River

“…Seasonal fluctuations in Cladocera numbers revealed the lowest count in summer (233 ind./m 3 ) and the highest in autumn (1678 ind./m 3 ) (Table 2), consistent with findings by Mola et al and Mola and Ahmed) [47,48], attributing the decline in Cladocera abundance during summer to elevated water temperatures. The peak in Cladocera populations during autumn suggests favorable temperatures and ample food availability, such as bacteria and suspended debris [49]. Additionally, as suggested by Pandey et al (2009) [50], heightened competition and fish predation with other groups may contribute to the reduced abundance of Cladocera during summer.…”

“…Sharma and Sharma [55] further emphasize that seasonal fluctuations in dissolved oxygen concentrations can impact the activity and population levels of zooplankton. Additionally, Obuid-Allah et al [49] noted that biological metabolism rates and the utilization of oxygen by organisms are directly influenced by water temperature, with higher temperatures leading to increased biological abundance, thereby underscoring the critical role of dissolved oxygen levels in aquatic ecosystems. Brachionus was the most abundant genus of Rotifera in the present study, constituting 50% of all Rotifer species, represented by 9 species.…”