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The Hydrological Effects of a Wildfire in a Eucalypt Afforested Catchment
Item type: Journal Article • Journal: South African Forestry Journal • Authors: D.F. Scott --- Division of Forest Science and Technology, Jonkershoek Forestry Research Centre, RSA R.E. Schulze --- Department of Agricultural Engineering, RSAA high-intensity wildfire through a humid, upland catchment which was partially afforested to Eucalyptus fastigata, markedly increased stormflows and caused high soil losses off the afforested slopes. Total streamflow yield was unchanged but baseflow was reduced after the fire. The... -
Soil water variability in the Weatherley grassland catchment, South Africa: I. Evapotranspiration
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: CW van Huyssteen --- Department of Soil, Crop and Climate Sciences, South Africa TB Zere --- Department of Soil, Crop and Climate Sciences, South Africa M Hensley --- Department of Soil, Crop and Climate Sciences, South AfricaEvapotranspiration (ET) is a major component of the soil water balance and therefore requires accurate determination to quantify catchment water yield. Six-year daily ET was determined at 300 mm depth intervals in the root zone of 28 soil profiles in... -
THE INFLUENCE OF P-RETENTION BY SOILS AND SEDIMENTS ON THE WATER QUALITY OF THE LIONS RIVER
Item type: Journal Article • Journal: Journal of the Limnological Society of Southern Africa • Authors: H.D. Furness C.M. BreenThe soils of Midmar dam catchment and the sediments of the Lions river are shown to have high P-retention properties. Present conditions result in little leaching of PO4 −4 from the soils and favour a net transport of P from... -
RATE OF EROSION IN THE CATCHMENT OF THE BULBERGFONTEIN DAM NEAR REDDERSBURG IN THE ORANGE FREE STATE
Item type: Journal Article • Journal: Journal of the Limnological Society of Southern Africa • Authors: J.S. Ie Roux --- Department of Geography, South Africa Z.N. Roos --- Department of Geography, South AfricaThe volume of sediment in the Bulbergfontein Dam was computed after mapping the area of the dam and ascertaining the depth of the sediment by digging and augering. The watershed of the impoundment had been delimited by means of aerial... -
BREEDING BEHAVIOUR OF THE MPASA, OPSARIDIUM MICROLEPIS (GUNTHER) (PISCES:CYPRINIDAE), IN LAKE MALAWI
Item type: Journal Article • Journal: Journal of the Limnological Society of Southern Africa • Authors: D. Tweddle --- Fisheries Department, MalawiObservations on the breeding behaviour of mpasa, a commercially valuable cyprinid endemic to Lake Malawi, were conducted in the Bua and North Rukuru Rivers. The spawning run takes place over an extended period during and after the rains, with an... -
WATER QUALITY MODELLING PERCEPTIONS OF A WATER RESOURCE MANAGEMENT ORGANIZATION
Item type: Journal Article • Journal: Journal of the Limnological Society of Southern Africa • Authors: H.D. Furness --- Scientific Services Division, South Africa W.N. Richards --- Scientific Services Division, South AfricaThe use of models by the South African water industry is discussed. It is suggested that climatic conditions and existing legislation have influenced the formulation of models. Future model requirements by the water Industry are outlined. Changes are suggested which... -
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... -
PHYSICAL, CHEMICAL AND BIOTIC RESPONSES TO DECREASING WATER DEPTH IN A HIGHVELD PAN FOLLOWING WET AND DRY SUMMERS
Item type: Journal Article • Journal: Southern African Journal of Aquatic Sciences • Authors: KH Rogers --- Department of Botany, WN Ellery --- Department of Botany, NL Winternitz --- Department of Botany, R Dohmeier --- Department of Botany,The classification of highveld pans by Geldenhuys (1982) emphasized the spatial diversity of morphology, vegetation and fauna. However, since the characteristics of individual pans also change seasonally and over longer term wet/dry cycles, he called for more detailed limnological studies... -
THE BENTHIC MACROINVERTEBRATE FAUNA OF A SOUTH AFRICAN MOUNTAIN STREAM AND ITS RESPONSE TO FIRE
Item type: Journal Article • Journal: Southern African Journal of Aquatic Sciences • Authors: D.L. Britton --- Freshwater Research Unit, Zoology Department, South AfricaThe effects of a late-summer prescribed burn on the temperature and benthic macroinvertebrate fauna of a south-western Cape mountain stream were investigated over a period of 12 months. Temperature and discharge regimes appear well-defined and relatively predictable from year to... -
MANAGEMENT OPTIONS FOR SHALLOW HYPERTROPHIC LAKES, WITH PARTICULAR REFERENCE TO ZEEKOEVLEI, CAPE TOWN
Item type: Journal Article • Journal: Southern African Journal of Aquatic Sciences • Authors: W.R. Harding --- , South Africa A. J.R. Quick --- , South AfricaZeekocvlei, a freshwater coastal lake, is an important regional recreation area in the south-western Cape, South Africa. The lake is hypertrophic, experiences perenially dense populations of cyanobacteria (Microcystis), invasive bulrush and reed encroachment, and has a thick benthic layer of... -
AN HOLISTIC APPROACH TO THE MANAGEMENT OF WATER QUALITY IN FALSE BAY, CAPE TOWN, SOUTH AFRICA
Item type: Journal Article • Journal: Southern African Journal of Aquatic Sciences • Authors: A. J.R. Quick --- Town Planning Branch, Cape Town City Council, South AfricaAn overview of the water quality status of False Bay identified the bacterial/viral water quality of stormwater and rivers discharging near contact recreation beaches to be the management concern of highest priority. A second water quality concern is the potential... -
Developing a protocol for managing the biophysical condition of a water management area: the Sabie catchment case study
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: E van Wyk J Jaganyi B van Wilgen C Breen K Rogers D Roux F VenterRecent modification of the South African Water Law spells out fundamental changes for the way the country's water resources will be managed in the future. One of the most significant mandates is the establishment of Catchment Management Agencies (CMAs) and... -
Catchments as conservation units for riverine biodiversity
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: MJ WishartThe geological structure and longitudinal nature of river systems provide a possible barrier to the dispersal of lotic organisms. This has the potential to drive evolutionary processes such as genetic differentiation and subsequent allopatric speciation. In the conservation of lotic... -
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 cost of water hyacinth control in South Africa: a case study of three options
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: E van Wyk --- , South Africa BW van Wilgen --- , South AfricaThe aquatic plant water hyacinth (Eichhornia crassipes) was first recorded in South Africa during the early part of the 20th century. The plant has since spread across the country and is found in water bodies in both sub-tropical and temperate... -
Human impacts on hydrological health and the provision of ecosystemservices: a case study of the eMthonjeni–Fairview Spring Wetland, Grahamstown, South Africa
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: M Sinchembe --- Department of Environmental Science, South Africa WN Ellery --- Department of Environmental Science, South AfricaWetland hydrological health and the provision of indirect ecosystem services in the eMthonjeni–Fairview Spring Wetland, Grahamstown, South Africa, were assessed in 2008, using the newly developed wetland assessment tools WET-Health and WET-EcoServices. Variation in health and ecosystem services were assessed... -
Physical and chemical characteristics of the Tanzanian inshore and offshore waters of Lake Victoria in 2005–2008
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: GW Ngupula --- , Tanzania CN Ezekiel --- , Tanzania IA Kimirei --- , Tanzania E Mboni --- , Tanzania BB Kashindye --- , TanzaniaAssuming that the inshore and offshore waters of Lake Victoria are impacted differently by human activities in its catchment, this study investigated the water quality dynamics of the lake. A total of 29 stations were sampled in 2005–2008 for dissolved... -
Treatment Effects on Annual and Dry Period Streamflow at Cathedral Peak
Item type: Journal Article • Journal: South African Forestry Journal • Authors: J.M. Bosch --- Department of Forestry,Total annual streamflow and dry season flows of treated catchments at Cathedral Peak, Natal, were compared and related to those of index catchments. -
WATER QUALITY MODELLING PERCEPTIONS OF A WATER RESOURCE MANAGEMENT ORGANIZATION
Item type: Journal Article • Journal: Southern African Journal of Child and Adolescent Mental Health • Authors: H.D. Furness --- Scientific Services Division, South Africa W.N. Richards --- Scientific Services Division, South AfricaThe use of models by the South African water industry is discussed. It is suggested that climatic conditions and existing legislation have influenced the formulation of models. Future model requirements by the water Industry are outlined. Changes are suggested which... -
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... -
A new approach to modelling streamflow reductions resulting from commercial afforestation in South Africa
Item type: Journal Article • Journal: The Southern African Forestry Journal • Authors: M.B. Gush --- Environmentek CSIR, D.F. Scott --- Department of Earth and Environmental Sciences, Canada G.P.W. Jewitt --- School of Bio-Resources Engineering and Environmental Hydrology, R.E. Schulze --- School of Bio-Resources Engineering and Environmental Hydrology, L.A. Hallowes --- , A.H.M. Görgens --- Dept. of Civil Engineering,The Department of Water Mfairs and Forestry has, for some time, needed a comprehensive tool to incorporate the impacts of commercial afforestation on water resources into water use authorisation and allocation processes. Simulation modelling on a national scale, using the... -
The impact of feedlot effluent on water quality and aquatic macroinvertebrate community structure in streams of the upper Vaal River catchment, South Africa
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: M-N Jonker --- Centre for Aquatic Research, Department of Zoology, South Africa JHJ van Vuren --- Centre for Aquatic Research, Department of Zoology, South Africa V Wepener --- Centre for Aquatic Research, Department of Zoology, South AfricaThe impact of three intensive feedlots on aquatic macroinvertebrate community structure under high and low flows in the upper Vaal catchment was investigated. Water quality variables recorded upstream and downstream of feedlot activity include pH, dissolved oxygen, conductivity, temperature, turbidity,... -
Abundance, composition and distribution of solid wastes in the Tanzanian waters of Lake Victoria
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: GW Ngupula --- Tanzania Fisheries Research Institute (TAFIRI), Tanzania RJ Kayanda --- Tanzania Fisheries Research Institute (TAFIRI), Tanzania CA Mashafi --- Tanzania Fisheries Research Institute (TAFIRI), TanzaniaThe abundance, composition and distribution of solid waste in the Tanzanian waters of Lake Victoria were quantified during surveys in May and October 2013 at 68 stations in six depth strata using the bottom trawl swept area method. By weight,... -
Preliminary evaluation of non-native rainbow trout (Oncorhynchus mykiss) impact on the Cederberg ghost frog (Heleophryne depressa) in South Africa’s Cape Fold Ecoregion
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: S Avidon --- Department of Conservation Ecology and Entomology, South Africa JM Shelton --- Department of Conservation Ecology and Entomology, South Africa SM Marr --- DST/NRF Research Chair in Inland Fisheries and Freshwater Ecology, South Africa TA Bellingan --- Centre for Invasion Biology, South Africa KJ Esler --- Department of Conservation Ecology and Entomology, South Africa OLF Weyl --- DST/NRF Research Chair in Inland Fisheries and Freshwater Ecology, South AfricaWe evaluated the impact of non-native rainbow trout Oncorhynchus mykiss on a population of endemic Cedarberg ghost frog Heleophryne depressa in the upper Krom River (Olifants-Doring River Catchment, Cape Fold Ecoregion). We compared H. depressa abundance (using kick-sampling and underwater... -
The development and implementation of a management plan for the Seekoei Estuary, South Africa: a case study guided by socio-economic issues
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: TH Wooldridge --- Department of Zoology and Institute for Coastal and Marine Research, South Africa JB Adams --- Department of Botany and Institute for Coastal and Marine Research, South AfricaThe large Temporarily Closed Seekoei Estuary has a long history of poor management. In 1969, a swimming pool complex was built in a position impinging on the mouth. The construction of a 500 m causeway across the lagoon connecting the... -
Benthic macrofaunal changes in response to restoration efforts in the St Lucia estuarine lake, South Africa
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: PC Moloi --- School of Agriculture and Science, University of KwaZulu-Natal, South Africa GM Rishworth --- Department of Zoology, Institute for Coastal and Marine Research, Nelson Mandela University, South Africa MS Bird --- Department of Zoology, University of Johannesburg, South Africa NK Carrasco --- School of Agriculture and Science, University of KwaZulu-Natal, South AfricaThe St Lucia estuarine lake and Mfolozi River mouth on the Indian Ocean coast of South Africa were once a single, connected system but were artificially separated in 1952 to prevent siltation from the Mfolozi River catchment which risked shallowing...