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DISTINGUISHING SUB-ENVIRONMENTS OF SEDIMENT DEPOSITION IN RESERVOIRS USING PARTICLE SIZE DISTRIBUTION PARAMETERS
Item type: Journal Article • Journal: Journal of the Limnological Society of Southern Africa • Authors: A van B Weaver --- Department of Water Affairs, South Africa AW Stone --- Department of Water Affairs, South AfricaThe deposition of sediment and the distribution of sediment sizes in impoundments is related to the hydraulic mechanisms of the lacustrine or reservoir environment. Granulometric parameters of sediments can be particularly sensitive indicators of the hydraulic environments occuring in different... -
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... -
MODELS OF ECOSYSTEMS AND AQUATIC ENVIRONMENTS: DEVELOPMENT AND APPLICATION
Item type: Journal Article • Journal: Journal of the Limnological Society of Southern Africa • Authors: B.R. Allanson --- , South AfricaAn historical treatment of a number of principal events is given. This leads to an assessment of the current research approach in hydrobiology and its success in the development of process orientated ecosystem component models. With the contemporaneous development of... -
FUTURE CHALLENGES IN WATER QUALITY MODELLING WITH PARTICULAR REFERENCE TO OPERATIONALLY CLOSED CATCHMENTS
Item type: Journal Article • Journal: Journal of the Limnological Society of Southern Africa • Authors: S.F. Forster --- Department of Water Affairs, South Africa F.A. Stoffberg --- Department of Water Affairs, South Africa J.A. van Rooyen --- Department of Water Affairs, South AfricaAs a result of the declining quality of many water sources, the use of water quality models in planning is increasing. To date applications have involved the simulation of total dissolved salts and nutrients, largely in catchments affected by urban... -
ASPECTS OF COMPARATIVE PLANKTON ECOLOGY IN CASCADING MGENI RIVER RESERVOIRS (MIDMAR, ALBERT FALLS, AND NAGLE): AN OVERVIEW
Item type: Journal Article • Journal: Southern African Journal of Aquatic Sciences • Authors: R.C. Hart --- Department of Zoology & Entomology, South AfricaAn overview of a three year study of abundance, community structure and succession of zooplankton and phytoplankton in relation to physical limnological conditions in Lakes Midmar and Albert Falls is presented, along with findings on zooplankton from a nine month... -
A COMPARISON OF CYPRINID FISH POPULATIONS IN THREE LARGE TRANSKEI RESERVOIRS WITH RESPECT TO ABUNDANCE AND REPRODUCTION
Item type: Journal Article • Journal: Southern African Journal of Aquatic Sciences • Authors: M. Schramm --- Zoology Department, South AfricaGill net catches of fish in three turbid reservoirs (Lakes Xonxa and Lubisi on the Kei River system and Lake Umtata on the Mtata River) between 1982 and 1985 were dominated by two cyprinids the common carp, Cyprinus carpio, and... -
PRELIMINARY OBSERVATIONS ON THE FISH POPULATIONS OF THE RECENTLY-IMPOUNDED KATSE RESERVOIR, LESOTHO
Item type: Journal Article • Journal: Southern African Journal of Aquatic Sciences • Authors: D. Tweddle --- , South Africa M. T.T. Davies --- , , South AfricaKatse is a new 35 km long impoundment on the Malibamatso River, a highland tributary of the Orange River in Lesotho. Two fishing surveys in 1996 yielded Barbus aeneus, Labeo capensis, Oncorhynchus mykiss and the occasional Austroglanis sclateri. Length frequency... -
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... -
Zooplankton abundance and composition in the hypertrophic Rietvlei Dam, South Africa, negate prospects for its remedial ‘top-down’ biomanipulation
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: RC Hart --- School of Life Sciences, South AfricaCrustacean zooplankton abundance and composition were determined at one offshore and three nearshore sites in the hypertrophic Rietvlei Dam on 19 dates between July 2009 and December 2011. Total biomass fluctuated seasonally, generally declining from spring to winter through the... -
A study of the ichthyofauna of a small tropical reservoir, south-eastern lowveld, Zimbabwe
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: T Dalu --- Department of Biological Sciences, Zimbabwe BW Clegg --- Malilangwe Wildlife Reserve, Zimbabwe T Nhiwatiwa --- Department of Biological Sciences, ZimbabweFish diversity in Malilangwe Reservoir in the south-eastern lowveld of Zimbabwe was investigated in 2011 to determine the community structure. The aim of this study was to determine the current status of an artificial fish community in a small reservoir... -
MODELS OF ECOSYSTEMS AND AQUATIC ENVIRONMENTS: DEVELOPMENT AND APPLICATION
Item type: Journal Article • Journal: Southern African Journal of Child and Adolescent Mental Health • Authors: B.R. Allanson --- , South AfricaAn historical treatment of a number of principal events is given. This leads to an assessment of the current research approach in hydrobiology and its success in the development of process orientated ecosystem component models. With the contemporaneous development of... -
FUTURE CHALLENGES IN WATER QUALITY MODELLING WITH PARTICULAR REFERENCE TO OPERATIONALLY CLOSED CATCHMENTS
Item type: Journal Article • Journal: Southern African Journal of Child and Adolescent Mental Health • Authors: S.F. Forster --- Department of Water Affairs, South Africa F.A. Stoffberg --- Department of Water Affairs, South Africa J.A. van Rooyen --- Department of Water Affairs, South AfricaAs a result of the declining quality of many water sources, the use of water quality models in planning is increasing. To date applications have involved the simulation of total dissolved salts and nutrients, largely in catchments affected by urban... -
Effect of an impoundment on nutrient dynamics in the Kihansi River, Tanzania
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: RJ Ideva J Machiwa F Schiemer T HeinThe impact of the Kihansi Dam on electrical conductivity, pH, temperature and dissolved oxygen in the Kihansi River was assessed in 2005 after 85% of the original river flow had been diverted to the Lower Kihansi power plant. The results... -
Rapid biological assessment of the fishery potential of Xonxa Dam, near Queenstown, South Africa
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: TJ Richardson AJ Booth OLF WeylRapid biological assessments have been proposed as the most cost-effective approach to identify suitable target species and to set initial catch and fishing effort levels for new fisheries. Xonxa Dam, a turbid irrigation dam situated in the White Kei catchment,... -
Adult African sharptooth catfish, Clarias gariepinus, population dynamics in a small invaded warm-temperate impoundment
Item type: Journal Article • Journal: African Zoology • Authors: Anthony J. Booth --- Department of Ichthyology and Fisheries Science, South Africa Graham R.L. Traasg --- Department of Ichthyology and Fisheries Science, South Africa Olaf L.F. Weyl [AN0002]African sharptooth catfish, Clarias gariepinus, is a successful aquatic invader as it has a eurytopic physiology, is highly fecund, grows quickly and has an omnivorous diet. Despite possible threats that include predation of and competition with indigenous species, habitat degradation,... -
Occurrence of Tetracampos ciliotheca (Cestoda: Bothriocephalidea) in the gall bladder of Clarias anguillaris in Burkina Faso
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: Y Sinaré --- Laboratoire de Biologie et Ecologie Animales, Département de Biologie et Physiologie Animales, Burkina Faso M Boungou --- Laboratoire de Biologie et Ecologie Animales, Département de Biologie et Physiologie Animales, Burkina Faso A Ouéda --- Laboratoire de Biologie et Ecologie Animales, Département de Biologie et Physiologie Animales, Burkina Faso K Mano --- Laboratoire de Biologie et Ecologie Animales, Département de Biologie et Physiologie Animales, Burkina Faso WN Kpoda --- Laboratoire de Biologie et Ecologie Animales, Département de Biologie et Physiologie Animales, Burkina Faso NG Sakiti --- Département de Zoologie, Benin GB Kabré --- Laboratoire de Biologie et Ecologie Animales, Département de Biologie et Physiologie Animales, Burkina FasoThe presence of the bothriocephalidean cestode Tetracampos ciliotheca Wedl, 1861 is reported from the gall bladders of the catfish Clarias anguillaris from Loumbila and Ziga reservoirs, Burkina Faso, in 2010–2011. Of the 159 specimens examined, 47 were infected. Mean intensity... -
First record of a spiral form of Aulacoseira, A. ambigua f. japonica (F.Meister) Tuji & D.M.Williams, in South African fresh waters
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: S Janse van Vuuren --- Unit for Environmental Sciences and Management, North-West University, South Africa JC Taylor --- Unit for Environmental Sciences and Management, North-West University, South AfricaWater quality and algal populations in the Vaal River Barrage Reservoir have been monitored extensively for many decades, because of its importance as a water source for the most densely populated area in South Africa. Although Aulacoseira granulata (Ehrenberg) Simonsen... -
Xenopus laevis as UberXL for nematodes
Item type: Journal Article • Journal: African Zoology • Authors: Anneke L Schoeman --- African Amphibian Conservation Research Group, Unit for Environmental Sciences and Management, South Africa Tracy-Lee Joubert --- African Amphibian Conservation Research Group, Unit for Environmental Sciences and Management, South Africa Louis H du Preez --- African Amphibian Conservation Research Group, Unit for Environmental Sciences and Management, South Africa Roman Svitin --- African Amphibian Conservation Research Group, Unit for Environmental Sciences and Management, South AfricaThe effect of invasive species on local parasite dynamics is often overlooked. The African Clawed Frog Xenopus laevis (Daudin, 1802) (Anura: Pipidae) is a global invader, with established populations on four continents and is a domestic exotic in southern Africa... -
Physico-chemical limnology during the filling phase of Tugwi-Mukosi, a tropical reservoir in Zimbabwe
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: L Mhlanga --- , Harare TC Madzivanzira --- , Zimbabwe T Nhiwatiwa --- , Harare P Tendaupenyu --- , Harare M Barson --- , Harare L Marufu --- , Harare N Songore --- , ZimbabweThe physico-chemical limnology and trophic status of the Tugwi-Mukosi reservoir were assessed seven months after impoundment. Water temperature, conductivity, pH, dissolved oxygen, transparency, nitrates, total nitrogen, orthophosphates, total phosphorus and metals (K, Na, Ca, Mg, Cu, Cd, Cr, Ni, Hg,... -
A survey of phytoplankton and zooplankton communities in the newly created Tugwi-Mukosi reservoir, Zimbabwe, during the filling phase
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: L Mhlanga --- , Zimbabwe TC Madzivanzira --- , Zimbabwe T Nhiwatiwa --- , Zimbabwe P Tendaupenyu --- , Zimbabwe M Barson --- , Zimbabwe L Marufu --- , Zimbabwe N Songore --- , ZimbabweThe plankton assemblages of Tugwi-Mukosi reservoir in south-eastern Zimbabwe were assessed seven months after impoundment to form a baseline for future monitoring and tracking of changes linked to the reservoir’s ontogenetic development processes. While cyanobacteria were the dominant group at... -
Littoral substrates and nest properties of Coptodon rendalli vary with distance from the shoreline in a tropical impoundment, southeast Zimbabwe
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: RJ Chateya --- National University of Science and Technology, Zimbabwe HGT Ndagurwa --- National University of Science and Technology, ZimbabweThe change in littoral substrates and Coptodon rendalli nest properties along the inshore–offshore gradient of Mushandike Dam in southeast Zimbabwe, impacted by long-term water-level fluctuations, were studied in March 2016. Substrate and nest properties were measured in four contiguous 25...