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THE INTERRELATIONSHIPS BETWEEN THE BIOLOGICAL AND PHYSICO-CHEMICAL PARAMETERS IN THE WATER PHASE OF SESHEGO DAM, NORTHERN TRANSVAAL
Item type: Journal Article • Journal: Journal of the Limnological Society of Southern Africa • Authors: Antoinette Jooste --- Department of Zoology and Biology, South AfricaSeshego Dam, Lebowa, was investigated over a period of 15 months (1974 – 1975). The interrelationships between biological parameters such as Biological Growth Potential (BGP), anaerobic fecal and coliform bacteria, Cladocera and Copepoda were established by means of factor and... -
INTER- AND INTRA-SPECIFIC ASSOCIATIONS AS SOME POSSIBLE PREDATOR AVOIDANCE AND ENERGY CONSERVATION STRATEGIES IN PLANKTONIC ROTIFERS
Item type: Journal Article • Journal: Journal of the Limnological Society of Southern Africa • Authors: J. Heeg --- Department of Zoology & Entomology, South Africa NancyA. Rayner --- Department of Zoology & Entomology, South AfricaDuring routine analysis of zooplankton samples from Lake Midmar, a warm temperate impoundment, several associations involving rotifer species were observed. These included: 1) the linking together of individuals of Hexarthra mira and Trichocerca chattoni to form chains; 2) phoretic associations... -
A comparison of methods for incubating zooplankton diapausing eggs from sediment of endorheic pans in the Free State, South Africa
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: SL Liefferink --- Department of Zoology, South Africa RB Tate --- Department of Zoology, South Africa JHJ van Vuren --- Department of Zoology, South Africa M Ferreira --- Department of Zoology, South Africa W Malherbe --- Unit for Environmental Sciences and Management, South AfricaDetermining the composition of zooplankton in endorheic pans can be challenging, and live sampling of these microcrustaceans does not give a true indication of their species diversity and abundance. The incubation of zooplankton diapausing eggs can assist in determining their... -
Competition and niche partitioning in a floodplain ecosystem: a cladoceran community squeezed between fish and invertebrate predation
Item type: Journal Article • Journal: African Zoology • Authors: Markus Lindholm --- Department of Biology, Norway Dag Olav Hessen --- Department of Biology, NorwaySeasonal floodplains occasionally comprise highly productive zooplankton communities which are exposed to rapid shifts in predator regimes, also between vertebrate and invertebrate predators.We recorded the impact of two co-occurring zooplankton predators, the notonectid Anisops sardea and 0+ fish fry of... -
Diversity, dispersal and disturbance: cladoceran species composition in the Okavango Delta
Item type: Journal Article • Journal: African Zoology • Authors: Markus Lindholm --- Norwegian Institute for Water Research/NIVA, Norway Dag O. Hessen --- Department of Biology, Norway Lars Ramberg --- Harry Oppenheimer Okavango Research Centre, University of Botswana, BotswanaCommunities exposed to intermediate disturbances have been shown to be more diverse than more stable or unstable systems. We recorded the diversity pattern of zooplankton in the Okavango Delta, Botswana, a system which include water bodies with different stability with... -
Zooplankton composition of temporary pools within the lower Nata River channel, Botswana, during dry season
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: DT West --- , South Africa LL van As --- , South AfricaThe Nata River is a seasonal system situated in the semi-arid north-eastern Botswana, where rainfall is unpredictable and drought is common. The annual flow of approximately 279 million cubic meters is regionally significant and it forms an important resource for... -
Zooplankton communities in Lake Nasser, Egypt, under the current flood regime, before the construction of Grand Ethiopian Renaissance Dam (GERD)
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: Mahmoud H Hegab --- , Egypt Nehad Khalifa --- , Egypt Walid Aly --- , EgyptThis study focuses on changes in zooplankton composition and abundance in Lake Nasser during different flood periods before the construction of the Grand Ethiopian Renaissance Dam (GERD). Field surveys were carried out in August 2016 (flood period), December 2016 (post-flood... -
Potential live feeds for larval fish culture in Ethiopia
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: Solomon Melaku --- , Ethiopia Abebe Getahun --- , Ethiopia Seyoum Mengestou --- , Ethiopia Akewake Geremew --- , Ethiopia Amha Belay --- , United StatesThe artificial propagation of commercially important fish species in Ethiopia is constrained by high mortality rate at the early stage of larval rearing and a subsequent poor growth performance during later stages. This is mainly due to absence of live... -
Zooplankton distribution and community structure as a function of environmental variables in the Niger River and its tributaries in Niger
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: H Souley Adamou --- Université de Toulouse, France B Alhou --- Université Abdou Moumouni de Niamey, Niger M Tackx --- Université de Toulouse, France F Azémar --- Université de Toulouse, FranceThe Niger River and its main tributaries (Sirba, Tapoa and Mékrou) in Niger were sampled during high and low water flow with the objectives of (1) comparing the taxonomic structure, diversity and abundance of the zooplankton community (rotifers, copepods, crustaceans)...