Inleidende studie van de zooplanktongemeenschap van een mangrove kreek (Kenya) = Introductory study of the zooplankton community of a mangrove creek (Kenya)
Borger, R. (1990). Inleidende studie van de zooplanktongemeenschap van een mangrove kreek (Kenya) = Introductory study of the zooplankton community of a mangrove creek (Kenya). MSc Thesis. Vrije Universiteit Brussel: Brussel. 69 pp. |
Available in | Author | | Document type: Dissertation
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Keywords | Aquatic communities > Plankton > Zooplankton Acartia natalensis Connell & Grindley, 1974 [WoRMS]; Calanoida [WoRMS]; Oithona brevicornis Giesbrecht, 1891 [WoRMS]; Pseudodiaptomus stuhlmanni (Poppe & Mrázek, 1895) [WoRMS]; Tortanus capensis Grindley, 1978 [WoRMS] ISW, Kenya, Gazi Bay [Marine Regions] Brackish water |
Abstract | In this work the zooplankton population structure of a mangrove creek in Gazi (Kenya) is studied. The first part of the study includes density, diversity and respiration measurements of zooplankton during three 24 hour cycles. Abiotic parameters (salinity, temperature and oxygen saturation of the water) were measured at the same time. From variations of salinity and oxygen concentration with the tide, it appears that the watermass is almost completely renewed at each high tide. The most common zooplankton group are the nauplii. Oithona brevicornis is the most abundant copepod species. The density and diversity of tbe zooplankton are also influenced by the tidal system. Presumably several zooplankton groups perform vertical migrations to the bottom,to avoid being washed out to the ocean. The highest zooplankton densities are measured at low tide, especially at night. With high tide a diluting effect seems to occur, in addition to a current driven movement of zooplankton groups. The respiration of plankton per unit dry weight did not show any definite day /night rhythm. The second part of this work is a study based on the morphological structure of the feeding appendages of three calanoid species. This gives information on the food habits of these species. According to the results, Tortanus capensis can be defined as a carnivore species. Acartia natalensis and Pseudodiaptomus stuhlmani on the other hand show a more omnivorous character. |
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