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PRELIMINARY RESULTS ON THE UPTAKE AND RELEASE OF 32P BY POTAMOGETON PECTINATUS
Item type: Journal Article • Journal: Journal of the Limnological Society of Southern Africa • Authors: J.H. Swanepoel --- , South Africa J.F. Vermaak --- , South AfricaThe absorption and release of 32PO4, by Potamogeton pectinatus L during winter was investigated using a partitioned container in which the roots were separated from the stems and leaves. 32PO4 is absorbed by the roots as well as the stems... -
AQUATIC MACROPHYTE COMMUNITIES OF THE WILDERNESS LAKES: COMMUNITY STRUCTURE AND ASSOCIATED ENVIRONMENTAL CONDITIONS
Item type: Journal Article • Journal: Journal of the Limnological Society of Southern Africa • Authors: Clive Howard-Williams --- , South AfricaThe structure and summer biomass (g m−2 dry mass) of the principal aquatic macrophyte communities of the Wilderness Lakes were measured. Both emergent and submerged communities were included in the study. Productivity estimates were made by multiplying biomass by production/biomass... -
STUDIES ON THE ZOOBENTHOS OF SOME SOUTHERN CAPE COASTAL LAKES. SPATIAL AND TEMPORAL CHANGES IN THE BENTHOS OF SWARTVLEI, SOUTH AFRICA, IN RELATION TO CHANGES IN THE SUBMERGED LITTORAL MACROPHYTE COMMUNITY
Item type: Journal Article • Journal: Journal of the Limnological Society of Southern Africa • Authors: B.R. Davies --- , South AfricaMajor changes in the benthic macro-invertebrate community of the littoral zone of Swartvlei, South Africa, took place between January and April 1978, and the equivalent months of 1980. These changes, which were associated with a collapse of the submerged littoral... -
ZOOPLANKTON AND ESTUARINE RELICT (BENTHIC) FAUNA IN LAKE MZINGAZI, A FRESHWATER COASTAL LAKE OF NATAL
Item type: Journal Article • Journal: Journal of the Limnological Society of Southern Africa • Authors: B.K. Fowles --- , South Africa C. G.M. Archibald --- , South AfricaLake Mzingazi, a natural, undisturbed freshwater coastal lake in the heart of the Richards Bay municipal area, is threatened by rapid urban and industrial growth. The previously unrecorded composition and distribution of zooplankton in the lake was studied during 1979... -
Louisiana crayfish (Procambarus clarkii) (Crustacea: Cambaridae) in Kenyan ponds: non-target effects of a potential biological control agent for schistosomiasis
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: DavidM Lodge SadieK Rosenthal KennethM Mavuti Wairimu Muohi Philip Ochieng SamanthaS Stevens BenjaminN Mungai GeraldM MkojiThe Louisiana crayfish (Procambarus clarkii) has been proposed as a biological control agent for the intermediate snail hosts (Bulinus and Biomphalaria spp.) of human schistosomes (Schistosoma haematobium and S. mansoni) in Kenya. Using laboratory and field experiments, we examined the... -
Variations and changes in habitat, productivity, composition of aquatic biota and fisheries of the Kyoga lake system: lessons for management
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: R Ogutu-Ohwayo --- National Fisheries Resources Research Institute, Uganda K Odongkara --- National Fisheries Resources Research Institute, Uganda W Okello --- National Fisheries Resources Research Institute, Uganda D Mbabazi --- National Fisheries Resources Research Institute, Uganda SB Wandera --- National Fisheries Resources Research Institute, Uganda LM Ndawula --- National Fisheries Resources Research Institute, Uganda V Natugonza --- National Fisheries Resources Research Institute, UgandaThe Kyoga lake system, which is c. 4 m deep, originally had a diverse fish fauna, extensive macrophytes and wetlands. Most (82%) of its water comes from Lake Victoria, is controlled through three dams and has a short residence time... -
ZOOPLANKTON AND ESTUARINE RELICT (BENTHIC) FAUNA IN LAKE MZINGAZI, A FRESHWATER COASTAL LAKE OF NATAL
Item type: Journal Article • Journal: Southern African Journal of Child and Adolescent Mental Health • Authors: B.K. Fowles --- , South Africa C. G.M. Archibald --- , South AfricaLake Mzingazi, a natural, undisturbed freshwater coastal lake in the heart of the Richards Bay municipal area, is threatened by rapid urban and industrial growth. The previously unrecorded composition and distribution of zooplankton in the lake was studied during 1979... -
A review of the ecology and management of temporarily open/closed estuaries in South Africa, with particular emphasis on river flow and mouth state as primary drivers of these systems
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: AK Whitfield --- , South Africa GC Bate --- Department of Botany, South Africa JB Adams --- Department of Botany, South Africa PD Cowley --- , South Africa PW Froneman --- Department of Zoology and Entomology, South Africa PT Gama --- Department of Botany, South Africa NA Strydom --- Department of Zoology, South Africa S Taljaard --- , South Africa AK Theron --- , South Africa JK Turpie --- , South Africa L van Niekerk --- , South Africa TH Wooldridge --- Department of Zoology, South AfricaResearch in South African temporarily open/closed estuaries that includes studies on the hydrodynamics, sediment dynamics, macronutrients, microalgae, macrophytes, zoobenthos, hyperbenthos, zooplankton, ichthyoplankton, fishes and birds is used as a basis to review the ecology and management of this estuary type... -
Seasonal distribution and activity of nitrogen-cycling bacteria in Bardawil Lagoon, Egypt
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: A Dewedar --- Department of Botany, Egypt M Bahgat --- Faculty of Sciences, Egypt EE Shabana --- Department of Botany, EgyptThe ecological significance of Bardawil Lagoon, the only oligotrophic hypersaline lagoon on the Mediterranean coast of Egypt, was assessed through studying counts, activities and the distribution of nitrogen-cycling bacteria. Counts and activities of ammonifying bacteria, ammonium-oxidising microbes (AOM) and nitrite-oxidising... -
Responses of primary producers to mouth closure in the temporarily open/closed Great Brak Estuary in the warm-temperate region of South Africa
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: M Nunes --- Department of Botany, South Africa JB Adams --- Department of Botany, South AfricaLow river inflow conditions during 2009/2010 resulted in the mouth of the Great Brak Estuary remaining closed for almost two years. The low water level in Wolwedans Dam resulted in no annual environmental flow releases being made, causing mouth closure... -
The inshore benthic macroinvertebrates of Lake Nabugabo, Uganda: seasonal and spatial patterns
Item type: Journal Article • Journal: African Zoology • Authors: J. Efitre --- Zoology Department, Uganda L.J. Chapman --- Department of Zoology, U.S.A. B. Makanga --- Zoology Department, UgandaLake Nabugabo, Uganda, is a lake of particular interest because of the unusual nature of its benthic macroinvertebrate community. In this study we quantified the spatial and temporal distribution of benthic macroinvertebrates within the lakewith a focus on habitat associations... -
Ecology, fish and fishery of Lake Liambezi, a recently refilled floodplain lake in the Zambezi Region, Namibia
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: RA Peel --- Department of Ichthyology and Fisheries Science, Namibia D Tweddle --- South African Institute for Aquatic Biodiversity, Namibia EK Simasiku --- Department of Wildlife Management and Ecotourism, Katima Mulilo Campus, South Africa GD Martin --- Department of Zoology and Entomology, South Africa J Lubanda --- Ministry of Fisheries and Marine Resources, Namibia CJ Hay --- Department of Biological Sciences, Namibia OLF Weyl --- South African Institute for Aquatic Biodiversity, South AfricaLake Liambezi (300 km2) refilled in 2009 after a prolonged 22-year dry period. Its aquatic macrophyte populations, fish fauna and fishery shortly after refilling are described. The emergent aquatic macrophyte Phragmites australis formed dense stands covering large parts of the lake,... -
Mapping distribution of water hyacinth (Eichhornia crassipes) in Rwanda using multispectral remote sensing imagery
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: JA Mukarugwiro --- School of Animal, Plant and Environmental Sciences (APES), South Africa SW Newete --- School of Animal, Plant and Environmental Sciences (APES), South Africa E Adam --- School of Geography, Archaeology and Environmental Studies (GAES), South Africa F Nsanganwimana --- African Center of Excellence for Innovative Teaching & Learning Mathematics & Science, Rwanda KA Abutaleb --- Institute for Soil, Climate and Water, South Africa MJ Byrne --- School of Animal, Plant and Environmental Sciences (APES), South AfricaWater hyacinth, Eichhornia crassipes (C. Mart) Solms (Pontederiaceae), is an invasive aquatic macrophyte with major negative economic and ecological impacts in Rwanda and other East African countries since its establishment in the region in the 1960s. Reliable estimates of water... -
Diversity of macrophytes in relation to environmental conditions in wetlands along the lower part of the Gilgel Abay River catchment in Ethiopia
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: Habtamu Getnet --- , Ethiopia Seyoum Mengistou --- , Ethiopia Bikila Warkineh --- , EthiopiaThe environmental conditions in wetlands affect the diversity, composition, and distribution of their macrophyte communities. This study investigated the diversity of macrophytes as related to environmental conditions in wetlands of the lower part of Gilgel Abay River catchment in Ethiopia... -
Green technology for bioremediation of the eutrophication phenomenon in aquatic ecosystems: a review
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: Mostafa El-Sheekh --- , Egypt Mohamed M Abdel-Daim --- , Saudi Arabia Mohamed Okba --- , Egypt Samiha Gharib --- , Egypt Asgad Soliman --- , Egypt Hala El-Kassas --- , EgyptEutrophication is a serious phenomenon that leads to vigorous algal blooms that alters the structure of ecosystems. It is caused by non-point sources of nutrients; as nitrogen and phosphorus, and point sources as wastewater effluent. Distinctive algae groups are responsible... -
Spatial distribution of zooplankton in relation to some selected physicochemical water quality parameters of Lake Hawassa, Ethiopia
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: Getacher Beyene --- , Ethiopia Demeke Kifle --- , Ethiopia Tadesse Fetahi --- , EthiopiaWhile scientific information on spatial variation of freshwater zooplankton is relevant to limnological studies, little information is available from the Ethiopian Rift Valley lake: Lake Hawassa. This study aimed at understanding the spatial distribution of the dominant zooplankton taxa in... -
Spatio-temporal variation in phytoplankton community structure in backwaters of the Ketar River, central Ethiopia
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: Yadesa Chibsa --- Wachemo University, Ethiopia Seyoum Mengistou --- Addis Ababa University, Ethiopia Demeke Kifle --- Addis Ababa University, EthiopiaThis study assessed the spatio-temporal dynamics of the phytoplankton community in backwaters of the Ketar River, central Ethiopia, in relation to water quality and macrophyte coverage. Phytoplankton samples and physicochemical information were collected at six sites along the river over...