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ON THE STATUS OF CLARIAS GARIEPINUS (BURCHELL) IN LARGE MAN-MADE LAKES IN RHODESIA
Item type: Journal Article • Journal: Journal of the Limnological Society of Southern Africa • Authors: B.E. Marshall --- Department of National Parks and Wildlife Management, RhodesiaData from some large man-made lakes in Rhodesia suggest that the populations of Clarias gariepinus have declined in these lakes. The reasons for this are not clear although commercial fishing does not appear to be responsible. -
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... -
THE ENERGY BASE OF AQUATIC SYSTEMS IN SOUTH AFRICA
Item type: Journal Article • Journal: Journal of the Limnological Society of Southern Africa • Authors: B.R. Allanson --- Institute for Freshwater Studies, Department of Zoology, and Entomology, South AfricaThe energy base of reservoirs and lakes is examined. There is considerable variation in specific productivity and photosynthetic capacity depending on trophic condition and whether algae or suspensoids reduced transparency. While limnetic production is important in freshwater, it is not... -
ZOOPLANKTON AND ENVIRONMENTAL CONDITIONS IN A SOUTHERN CAPE COASTAL LAKE SYSTEM
Item type: Journal Article • Journal: Journal of the Limnological Society of Southern Africa • Authors: D.J. Coetzee --- Cape Department of Nature and Environmental Conservation, South AfricaThe usually natural closing and artificial opening of the Tow River mouth to the sea have a major influence on the physico-chemical environmental conditions in the coastal lake system formed by the Tow River, Eilandvlei, Langvlei and Rondevlei, as it... -
HYDROCLIMATE DEVELOPMENT FOLLOWING IMPOUNDMENT IN A TROPICAL AFRICAN MAN-MADE LAKE (LAKE ROBERTSON, ZIMBABWE)
Item type: Journal Article • Journal: Journal of the Limnological Society of Southern Africa • Authors: N.G. Cotterill --- Hydrobiology Research Unit, Zimbabwe J.A. Thornton --- Hydrobiology Research Unit, ZimbabweLake Robertson was impounded by the Darwendale Dam which was completed in late 1976 to supplement the water supply to the City of Harare, Zimbabwe. This paper presents the results of a fortnightly sampling programme conducted on the lake between... -
NUTRIENTS IN AQUATIC ECOSYSTEMS: AN INTRODUCTION TO SIMILARITIES BETWEEN FRESHWATER AND MARINE ECOSYSTEMS
Item type: Journal Article • Journal: Journal of the Limnological Society of Southern Africa • Authors: P Chapman --- , South Africa JA Thornton --- , South Africa -
NUTRIENTS IN AFRICAN LAKE ECOSYSTEMS: DO WE KNOW ALL?
Item type: Journal Article • Journal: Journal of the Limnological Society of Southern Africa • Authors: J.A. Thornton --- , South AfricaIt is nearly sixty years since the first studies were undertaken on the nutrient chemistry of African lakes. There have been numerous studies on the chemical composition of African waters in the intervening years. Yet as recently as five years... -
DECOMPOSITION IN FRESHWATER ECOSYSTEMS
Item type: Journal Article • Journal: Journal of the Limnological Society of Southern Africa • Authors: R.D. Robarts --- , South AfricaThis review examines the sources and composition of organic matter and the decomposition of particulate and dissolved organic matter (POM and DOM) in freshwater ecosystems. The main points to emerge from the review are listed below. -
ASPECTS OF EUTROPHICATION MANAGEMENT IN TROPICAL/SUB-TROPICAL REGIONS
Item type: Journal Article • Journal: Journal of the Limnological Society of Southern Africa • Authors: J.A. Thornton --- , South AfricaIn 1981, the UNESCO in association with the IIASA and OECD recognized that tropical/-sub-tropical water bodies may respond differently to eutrophication management techniques than heretofore expected on the basis of temperate lake studies. However, little information on the eutrophication process... -
TURBIDITY AND OTHER PHYSICAL FACTORS IN NATAL ESTUARINE SYSTEMS PART 2: ESTUARINE LAKES
Item type: Journal Article • Journal: Journal of the Limnological Society of Southern Africa • Authors: D.P. Cyrus --- Department of Zoology, South AfricaData on turbidity, temperature and salinity and the factors which affect them, such as wind and substratum, were collected from Natal's two estuarine Lakes. The effects of wind and substratum, were collected from Natal's two estuarine Lakes. The effects of... -
DISTRIBUTION AND ABUNDANCE OF THE BENTHOS IN THE SEDIMENTS OF LAKE CUBHU: A FRESHWATER COASTAL LAKE IN ZULULAND SOUTH AFRICA
Item type: Journal Article • Journal: Journal of the Limnological Society of Southern Africa • Authors: D.P. Cyrus --- Coastal Research Unit of Zululand, Department of Zoology, South Africa T.J. Martin --- Coastal Research Unit of Zululand, Department of Zoology, South AfricaA preliminary investigation of the macrobenthic invertebrates of the sediments of Lake Cubhu, a freshwater coastal lake near Richards Bay was conducted on a quarterly basis during 1987. The most important factor which determined the abundance and distribution of each... -
A QUARTER CENTURY OF GREAT LAKES RESEARCH IN AFRICA
Item type: Journal Article • Journal: Journal of the Limnological Society of Southern Africa • Authors: DavidH. Eccles --- , United KingdomThe African Great Lakes differ from shallower large African lakes by undergoing seasonal stratification and from large reservoirs in having long residence times, so that the ionic concentration of the lake water differs substantially from that of the inflows. -
THE DIURNAL MIXED LAYER IN LAKES AND OCEANS
Item type: Journal Article • Journal: Southern African Journal of Aquatic Sciences • Authors: JohnL. Largier --- Division of Earth, Marine and Atmospheric Science and Technology, South AfricaIn this review the current ideas on diurnal mixed layers are discussed with reference to several observations. Essentially, solar heating sets up a shallow thermocline which traps and concentrates further influx of heat and momentum in the top few metres... -
PRELIMINARY OBSERVATIONS ON THE MACROCRUSTACEA OF COASTAL LAKES IN THE VICINITY OF RICHARDS BAY, ZULULAND, SOUTH AFRICA
Item type: Journal Article • Journal: Southern African Journal of Aquatic Sciences • Authors: P.E. Reavell --- Department of Botany, South Africa D.P. Cyrus --- Coastal Research Unit of Zululand, Department of Zoology, South AfricaA limited amount of research has been carried out on the four coastal lakes in the Richards Bay area. Due to the impending threat of water pollution from industrial, mining and residential areas within the catchments of these lakes there... -
MASS MORTALITY OF MARINE AND ESTUARINE FISH IN THE SWARTVLEI AND WILDERNESS LAKE SYSTEMS, SOUTHERN CAPE.
Item type: Journal Article • Journal: Southern African Journal of Aquatic Sciences • Authors: I.A. Russell --- National Parks Board, South AfricaTwo incidences of mass mortality of fish were recorded in two saline waterbodies (Swartvlei estuary and Rondevlei) in the Wilderness National Park. Species affected were the Knysna seahorse (Hippocampus capensis) and longsnout pipefish (Syngnathus acus) in the Swartvlei estuary, and... -
FUNDUDZI, A UNIQUE, SACRED AND UNKNOWN SOUTH AFRICAN LAKE
Item type: Journal Article • Journal: Southern African Journal of Aquatic Sciences • Authors: B. C.W. van der Waal --- , ,Lake Fundudzi is a unique, small inland lake in the north eastern region of South Africa, formed by a landslide. The considerable sedimentation of its basin indicates an age in the order of 10 000s of years. It forms the... -
A LIMNOLOGICAL SYNOPSIS OF BHANGAZI SOUTH, A DYSTROPHIC COASTAL LAKE IN THE GREATER ST LUCIA WETLAND PARK (KWAZULU/NATAL), WITH COMMENTS ON ITS CONSERVATION VALUE.
Item type: Journal Article • Journal: Southern African Journal of Aquatic Sciences • Authors: R. C. Hart --- , , South Africa C. C. Appleton --- , , South AfricaBase-line limnological and biological data are given for Lake Bhangazi South, a small lake on the coastal plain of Kwazulu-Natal, South Africa. This shallow (Zmax < 6 m), subtropical lake is a warm and seemingly continuously polymictic system, but experiences... -
A REVIEW OF THE ICHTHYOFAUNA OF THE MHLATHUZE ESTUARY
Item type: Journal Article • Journal: Southern African Journal of Aquatic Sciences • Authors: S. P. Weerts --- , , D. P. Cyrus --- , ,The fish fauna of the Mhlathuze estuary was reviewed making reference to surveys dating from 1948 to 1997. The concept of Estuarine Dependence Category was employed to describe species affinities with the marine, estuarine and freshwater environments. -
Comparison of the density and species composition of aquatic invertebrates found between the roots of Eichhornia crassipes plants from two coastal lakes in northern KwaZulu-Natal
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: A Viljoen DP Cyrus V WepenerThe aquatic invertebrates found between the roots of Eichhornia crassipes plants from Lakes Cubhu and Nsezi were analysed and compared with each other. Root samples in Lake Cubhu were dominated by Corophium triaenonyx and Caridina nilotica whilst root samples from... -
Aquatic avifauna of the coastal lakes of the Mhlathuze River system
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: DP CyrusThis paper provides the first attempt to bring together all published and unpublished data on the aquatic avifauna of Lakes Mzingazi, Nsezi, Cubhu and Mangeza, situated near Richards Bay in the lower reaches of the Mhlathuze River system. Whilst the... -
Available information on macroinvertebrates of the Mhlathuze coastal lakes: setting the ecological reserve (lake water requirements)
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: CF Mackay DP CyrusThis paper reviews current information on the macroinvertebrates of four coastal lakes in the Mhlathuze catchment of Zululand. The fauna are described in terms of the potential influence of lake level changes in response to increasing anthropogenic pressures for available... -
The icthyofauna of the Mhlathuze coastal lakes: some preliminary results
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: SP Weerts DP CyrusThe fish faunas of the four Mhlathuze coastal lakes and the lower river comprise a diverse assortment of over fifty marine, estuarine and freshwater species. Three freshwater species are endemic to KwaZulu-Natal and nine estuarine species are endemic to southern... -
A preliminary assessment of impacts on estuarine associated fauna resulting from an intra-basin transfer and fresh water abstraction from aquatic systems in the Richards Bay area of KwaZulu-Natal, South Africa
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: D CyrusAn intra-basin transfer and the abstraction of water from aquatic systems in the Richards Bay area has led to the construction of six barriers which are restricting faunal movement, a reduction of flow to the Mhlathuze and Nhlabane estuaries and... -
Beacons in the limnological landscape
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: BR AllansonAn overview is given of a number of major developments in the limnology of South Africa, Zimbabwe and Namibia. None was possible without the involvement of enthusiastic investigators who, over some 70 years, stimulated the growth of freshwater research in... -
The phytoplankton of Great Bitter Lake, Egypt, including the impacts of nutrient-laden and heated effluents
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: HusseinE Touliabah WilliamD TaylorA year-long survey of the phytoplankton and nutrients in Great Bitter Lake indicates that this is a severely eutrophic lake. Chlorophyll levels were consistently high (>30μg/l), especially in summer (>90μg/l). The phytoplankton community comprised mostly diatoms and blue-green algae, although... -
Update on the bathymetry of Lake Mweru (Zambia), with notes on water level fluctuations
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: ArthurR Bos CyprianK Kapasa PaulAM van ZwietenA new bathymetric map of Lake Mweru was developed, displaying previously unknown morphological features and correcting the shape of the shoreline as presented in older maps. Water depth was measured during 11 transect cruises in early 1994. Two depressions were... -
Spatio-temporal variability of surface water quality parameters in a South African estuarine lake system
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: IA Russell --- , South AfricaLong-term (20+ years) water quality datasets for estuaries are rare, especially for smaller systems. Monitoring of salinity, temperature, pH, dissolved oxygen and turbidity has been undertaken since 1991 in the intensively utilised, modified, and managed temporarily open/closed Touw Estuary and... -
Nest characteristics of Yellow-billed Kites Milvus aegyptius in the Manambolomaty Lakes Complex, western Madagascar
Item type: Journal Article • Journal: Ostrich: Journal of African Ornithology • Authors: Tolojanahary Andriamalala --- , Madagascar Lily-Arison Rene de Roland --- , Madagascar Marius Rakotondratsima --- , Madagascar Gilbert Razafimanjato --- , Madagascar Russell Thorstrom --- , USAWe studied the nesting biology of Yellow-billed Kites Milvus aegyptius in the Manambolomaty Lakes Complex of western Madagascar during 2002 and 2003. We recorded 64 nesting attempts. In 2003, 33% (n = 39 nests) of the occupied nests were from... -
Study on the Prepressing of Flakeboard Containing Waste Paper
Item type: Journal Article • Journal: South African Forestry Journal • Authors: Günther Gerischer --- Faculty of Forestry, Rep. of South Africa Dave Reeves --- Faculty of Forestry, Rep. of South AfricaThe purpose of this study was to determine whether the strength properties of a composite board containing waste paper as a core material, could be improved by the prior prepressing of the core material before pressing the product to final... -
Toxic cyanobacteria in the lakes located in Rīga (the capital of Latvia) and its surroundings: present state of knowledge
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: M Balode I Purina S Strake S Purvina M Pfeifere I Barda K PovidisaThe intensity and toxicity of cyanobacterial blooms in lakes located near Rīga (the capital of Latvia) were investigated between 1998 and 2004. These lakes are shallow eutrophic water bodies with a high surface to depth ratio and are widely used... -
The zooplankton community of Lake Abo Zaabal, a newly-formed mining lake in Cairo, Egypt
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: RandaA El-Bassat WilliamD TaylorAbo Zaabal Lake, a new mining lake at the outskirts of Cairo, receives domestic sewage from a nearby village. We examined its chemical and biological properties in order to develop a plan to improve its ecosystem services. The pH ranged... -
The community composition and biomass of pelagic ciliated protozoa in East African lakes
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: AndrewW Yasindi WilliamD Taylor DenisH LynnThe community composition and biomass of planktonic ciliates were studied in 17 tropical East African lakes varying from freshwater to saline, and from oligotrophic to eutrophic. The conductivity of the lakes varied from 207μS cm−1 to 70 000μS cm−1. Chlorophyll... -
Post-mortem examination and sampling of African flamingos (Phoenicopteridae) under field conditions
Item type: Journal Article • Journal: Ostrich: Journal of African Ornithology • Authors: John E Cooper --- Faculty of Veterinary Medicine, Kenya Amy E Deacon --- Centre for Biological Diversity, UK Thomas Nyariki --- African Union–Interafrican Bureau for Animal Resources, KenyaRecent largely unexplained deaths in African flamingos have prompted the need for standard, reproducible methods for the post-mortem examination of these birds, for the taking of samples and for the recording of findings. Here we describe suitable techniques and present... -
Water quality monitoring in sub-Saharan African lakes: a review of remote sensing applications
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: T Dube --- School of Agricultural, Earth and Environmental Sciences, South Africa O Mutanga --- School of Agricultural, Earth and Environmental Sciences, South Africa K Seutloali --- School of Agricultural, Earth and Environmental Sciences, South Africa S Adelabu --- Department of Geography, South Africa C Shoko --- School of Bioresources Engineering and Environmental Hydrology, South AfricaWater quality deterioration in sub-Saharan Africa has attained a scale that requires scientific intervention. It is therefore important to devise appropriate and reliable techniques to investigate the water quality of lakes and reservoirs for the development of water resource management... -
The sensitivity of Afromontane tarns in the Maloti-Drakensberg region of South Africa and Lesotho to acidic deposition
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: JA Dunnink --- Centre in Water Research and Development (CiWaRD) and Department of Geography, South Africa CJ Curtis --- Centre in Water Research and Development (CiWaRD) and Department of Geography, South Africa JP Beukes --- Unit for Environmental Sciences and Management, South Africa PG van Zyl --- Unit for Environmental Sciences and Management, South Africa J Swartz --- Unit for Environmental Sciences and Management, South AfricaDespite their remoteness from sources of atmospheric pollutant emissions, the Afromontane tarns in the Maloti-Drakensberg region are perfect candidates to study the negative effects of acidifying atmospheric pollution, because mountain lakes are widely recognised as sentinel ecosystems, unimpacted by direct... -
Plankton composition, biomass, phylogeny and toxin genes in Lake Big Momela, Tanzania
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: MI Hamisi --- Department of Biotechnology and Bioinformatics, Tanzania C Lugomela --- Department of Aquatic Sciences and Fisheries Technology, Tanzania TJ Lyimo --- Department of Molecular Biology and Biotechnology, Tanzania B Bergman --- Department of Ecology, Environment and Plant Sciences, Sweden B Díez --- Department of Ecology, Environment and Plant Sciences, SwedenLake Big Momela, one of the East African soda lakes in Northern Tanzania characterised by highly saline-alkaline conditions, making them inhospitable to a range of organisms, although supporting massive growths of some adapted planktonic microorganisms that serve as food for... -
Mesozooplankton of the Kosi Bay lakes, South Africa
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: HL Jerling --- Department of Zoology and Coastal Research Unit of Zululand, South Africa SP Weerts --- Department of Zoology and Coastal Research Unit of Zululand, South AfricaThe Kosi coastal lake system, a chain of four interconnected basins, is located in the subtropical north-eastern corner of South Africa. Little information is available on zooplankton of the system and the main aim of this study is to report... -
Histological alterations of selected tissues (gill, liver, kidney and stomach) in two common fish species within two eutrophic peri-urban lakes in Zimbabwe
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: B Utete --- Department of Wildlife Ecology and Conservation, Zimbabwe N Mabika --- Department of Anatomy, Zimbabwe J Chiwara --- Department of Applied Biosciences and Biotechnology, Zimbabwe J Makaure --- Department of Applied Biosciences and Biotechnology, Zimbabwe C Phiri --- Department of Freshwater and Fishery Science, Zimbabwe SS Mlambo --- Department of Biotechnology Science, Zimbabwe N Muboko --- Department of Wildlife Ecology and Conservation, Zimbabwe J Tsamba --- Department of Biology, ZimbabwePollution threatens fish health in the eutrophic lakes, Chivero and Manyame, in Zimbabwe. Histopathological tissue alterations of two commonly consumed fish: catfish, Clarias gariepinus, and; tilapia, Oreochromis niloticus, from Lakes Chivero and Manyame were assessed between 2015 and 2016. Seventy-one... -
An Estuary Ecosystem Classification that encompasses biogeography and a high diversity of types in support of protection and management
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: L van Niekerk --- Council for Scientific and Industrial Research (CSIR), South Africa JB Adams --- DST/NRF Research Chair in Shallow Water Ecosystems, South Africa NC James --- DST/NRF Research Chair in Shallow Water Ecosystems, South Africa SJ Lamberth --- DST/NRF Research Chair in Shallow Water Ecosystems, South Africa CF MacKay --- Oceanographic Research Institute, SAAMBR, South Africa JK Turpie --- South African Institute for Aquatic Biodiversity, South Africa A Rajkaran --- Biodiversity and Conservation Biology, South Africa SP Weerts --- Council for Scientific and Industrial Research (CSIR), South Africa AK Whitfield --- South African Institute for Aquatic Biodiversity, South AfricaFor nearly three decades, the Whitfield (1992) characterisation scheme served as a reference framework to type South African estuaries. We outline a revised ecosystem classification scheme that incorporates biogeographical zonation and introduces new types. Coastal outlets were re-categorised as estuaries... -
Trends in chemical pollution and ecological status of Lake Ziway, Ethiopia: a review focussing on nutrients, metals and pesticides
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: LB Merga --- , The Netherlands AA Mengistie --- , Ethiopia JH Faber --- , The Netherlands PJ Van den Brink --- , The NetherlandsAquatic ecosystems contribute to human well-being by delivering ecosystem services, but their protection has been given low priority in Africa. Lake Ziway in the Ethiopian Rift Valley basin provides services including irrigation, drinking water and fish food in the region... -
Links between introduced fish and zooplanktonic and zoobenthic food sources in the food webs of two reservoirs of a semi-arid zone in Algeria
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: M Djezzar --- , Algeria JM Mortillaro --- , Madagascar SE Doumandji --- , Algeria T Meziane --- , FranceFew studies have focused on the trophic functioning of the reservoirs in Algeria. The study of the gut contents of fish species, as well as the analysis of the stable isotopes of 13C and 15N in the environment, were carried... -
Phylogenetic diversity of Actinobacteria from Momela soda lakes, Arusha National Park, Tanzania
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: Sadikiel E Kaale --- , Tanzania Ally Mahadhy --- , Tanzania Modester Damas --- , Tanzania Clarence A Mgina --- , Tanzania Thomas J Lyimo --- , TanzaniaThe Momela soda lakes consist of seven small, hypersaline, alkaline lakes, situated in the East African rift valley at Arusha National Park, Tanzania. The lakes are fed by separate underground water sources with slightly varying mineral contents resulting in colour... -
Comparison of physico-chemical parameters with macroinvertebrate and vertebrate fauna of Lake Ogelube and Lake Ojii, Opi-Agu, south-eastern Nigeria
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: IE Onah --- , OJ Ajanwachukwu --- , PO Ubachukwu --- ,The physico-chemical parameters of water provide crucial information on the condition of a waterbody at a point in time. Physico-chemical parameters determine the primary and secondary productivity of an aquatic ecosystem. Data on water temperature, pH, turbidity, water depth, total... -
Long-term trends from Citizen Scientists: 24 years of breeding success data of African Oystercatchers Haematopus moquini in the Garden Route
Item type: Journal Article • Journal: Ostrich: Journal of African Ornithology • Authors: B Arendse --- , South Africa P Dawson --- , South Africa B Mels --- , Ireland M Brown --- University of KwaZulu Natal, South AfricaLong-term data on breeding success in beach-nesting birds in southern Africa are scarce. Citizen science projects have risen to the forefront of large dataset collection efforts globally, with several local projects helping us unpack long-term trends for species in southern... -
Phylogenetic diversity of Actinomycetota species isolated from waters of Lake Natron, Arusha, Tanzania
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: Sadikiel E Kaale --- University of Dar es Salaam, Tanzania Robert S Machangu --- St. Francis University College of Health and Allied Sciences, Tanzania Thomas J Lyimo --- University of Dar es Salaam, TanzaniaActinomycetota are bacteria with biotechnological potential known to produce bioactive compounds in their natural ecosystems. Natural ecosystems include extreme environments such as soda lakes. Lake Natron is one of the soda lakes found in Arusha region, Tanzania. This study aimed...