Relationship between Dissolved Oxygen and the Vertical and Longitudinal Distribution of Zooplankton off the Namibian coast
Year: 2013
Type: article
Abstract: Zooplankton play an important role in the marine food web and are abundant on the \nNamibian coast, which is part of the highly productive Benguela upwelling system. In \nthe Benguela system zooplankton populations are dominated by copepods and euphausiids. \nThe abundance and distribution of zooplankton are affected by various environmental \nfactors such as temperature, light intensity and dissolved oxygen (DO). This study investigated \nthe relationship between DO and the diversity of zooplankton at different depths \nin the water column on the continental shelf off the Namibian coast. There was a positive \ncorrelation between DO and diversity of zooplankton offshore (Pearson’s r =0.83), \nwhile there exists a very weak positive correlation between DO and zooplankton diversity \nonshore (r= 0.196). Diversity of zooplankton does not differ significantly with depth at \nboth onshore and offshore stations (Shannon’s Index H0 < 1). However, Divesity of zooplankton \nbetween offshore (H0=2.8 to 3.6) and onshore (H0=0.8 to 0.9) stations differs \nsignificanty (p = 0:0271;d f = 4) in the top 90m, but is not significantly different below \n90m (p = 0:406;d f = 4). Nevertheless, the onshore stations had higher species richness \ncompared to the offshore stations. Dissolved oxygen does not have a direct effect on the \ndiversity of zooplankton, but an indirect effect and it is the interplay and interaction between \nseveral biological and environmental factors that affects zooplankton assemblage \ncomposition.
Authors: Elsabé Julies, Isak Kaholongo Kaholongo
Institution: University of Namibia
Language: English
Subfield: Oceanography
Field: Earth and Planetary Sciences
Domain: Physical Sciences
SDG: Life below water
Open Access status: diamond
OpenAlex ID: W2229456195