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The Influence of Site Factors on the Foliar Nutrient Content of Eucalyptus grandis in Natal
Item type: Journal Article • Journal: South African Forestry Journal • Authors: M.A. Herbert --- Institute for Commercial Forestry Research, South AfricaAlthough foliar analysis is commonly used to diagnose the nutritional status of trees and their ability to respond to fertilising, it is also a measure of site type and quality. The availability of nutrients in the soil varies with climatic... -
Effects of seed treatments on the germination of Atriplex nummularia Lindl.
Item type: Journal Article • Journal: Journal of the Grassland Society of Southern Africa • Authors: C.H. Donaldson --- Department of Agriculture (Karoo Region), Republic of South AfricaLaboratory experiments were conducted to determine the influence of length of soaking period and water temperature treatments on the germination of Atriplex nummularia. Germination percentages increased significantly (P≤0,01) with increasing soaking period in water with a temperature of 20°C, while... -
Epidemiology of ryegrass mosaic virus in South Africa
Item type: Journal Article • Journal: Journal of the Grassland Society of Southern Africa • Authors: SarahN. Salm --- , Republic of South Africa M.E. Christine Rey --- Department of Microbiology, Republic of South AfricaThe distribution and seasonal occurrence of ryegrass mosaic virus (RMV) in South Africa was determined. Italian ryegrass plants were collected from eight different research stations twice during the growing season in 1990 and 1991. Samples were tested for the presence... -
Die rol van sekere omgewingsfaktore by alachloraktiwiteit
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: C.F. Reinhardt --- Departement Plantproduksie, P.C. Nel --- Departement Plantproduksie,Biotoetse met graansorghum (Sorghum bicolor L.) is in potte in glashuise en groeikabinette uitgevoer. Geselekteerde grond- eienskappe is gekorreleer met alachloraktiwiteit. Organiese materiaalinhoud (% C) was die beste gekorreleerd met die aktiwiteit van alachlor en pH die swakste. Die r-waardes... -
Influence of temperature and daylength on the phenological development of annual Medicago species with particular reference to M. truncatula, cv. Jemalong
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: J.M. van Heerden --- Department of Agriculture,In a glasshouse and two growth-room trials, carried out in conjunction with 12 serial plantings in pots in the open, it was found that the phenological development of Medicago truncatula, M. tornata, M. aculeata, M. polymorpha, M. scutellata and M... -
Potato irrigation scheduling and straw mulching
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: M.S. Burgers --- Department of Plant Production, P.C. Nel --- Department of Plant Production,The effect of mulching and irrigation frequency on tuber yield was investigated during three seasons at the Glen Agricultural Research Institute The soil on the experimental site consisted of a loamy sand topsoil and sandy clay subsoil with 94 mm... -
Estimation of minimum temperature on a mesoscale
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: J. Myburgh --- ,Working relationships between mean minimum temperatures and environmental factors by means of regression techniques were established and used to estimate temperatures at gridpoints. These estimated temperatures were then used with a computer package program to map the isotherms on a... -
Influence of sub-optimal imbibition temperatures on seed vigour and respiration in maize (Zea mays L.)
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: H.A. van de Venter --- , N. Grobbelaar --- ,Germination and coleoptile growth of nine seed lots of maize (representing seven cultivars) were studied at 25°C (constant), 13°C (constant) and also at 7°C (7 days) followed by 25°C. Relative germination response to sub-optimal temperatures reflected relative differences in germination... -
Canopy temperature as a plant water stress indicator for nectarines
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: Helga Tormann --- ,Three-year-old nectarine trees of the cultivar Independence grown in free-drainage lysimeters were exposed to a wet and a dry treatment, i.e. high soil moisture content throughout or progressive soil drying respectively. The canopy temperature of the trees was measured with... -
In vivo atrazine hydroxylation in maize plants exposed to five different temperature regimes
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: C. Malan --- , J.H. Visser --- Department of Botany, H.A. van de Venter --- Department of Botany,Maize plants exposed to atrazine at temperatures ranging from 10°C to 30°C showed increased hydroxylation of atrazine to form the non-toxic hydroxy-atrazine metabolite as temperature increased to 25°C, above which hydroxylation decreased again. When exposed to 12 ppm atrazine, accumulation... -
Water storage, soil temperatures and maize (Zea mays L.) growth for various tillage practices
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: W. A.J. Berry --- Summer Grain Sub-Centre, Republic of South Africa J.B. Mallett --- Summer Grain Sub-Centre, Republic of South Africa P.L. Greenfield --- Department of Crop Science, Republic of South AfricaFour tillage treatments ranging from conventional mouldboard ploughing through to direct-drilling were repeated during the second season of an ongoing experiment. At commencement of the new season, differences in plant- available water (PAW) in the top 600 mm of the... -
Role of temperature in the activity of acetanilide herbicides on three Phaseolus taxa
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: E. van Rensburgd --- , Republic of South Africa L.P. van Dyk --- , Republic of South Africa G.H. de Swardt --- , Republic of South AfricaAlachlor [2-chloro-N-(2,6 diethylphenyl)-N-(methoxymethyl) acetamide], metolachlor [2-chloro-N-(2-ethyl-6- methylphenyl)-N-(2-methoxy-1 -methylethyl) acetamide] and acetochlor [2-chloro-N-(ethoxymethyl)-N-(2-ethyl-6- methyl-phenyl) acetamide], members of the chloroacetanilide herbicides, are used pre-emergence to control grasses and some broadleaf weeds. Two concentrations, i.e. 0,5 and 2 mg ai kg−1 of the... -
Relationships between yield, base temperature and drought resistance in grain sorghum
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: W.G. Wenzel --- , Republic of South AfricaThe object of this study was to investigate the interrelationship between yield, its components, base temperature and drought resistance of grain sorghum. Seven commercial cultivars and 27 F1 progenies were compared in two separate randomized block trials. A total of... -
Measurement of water potential in the trunks of citrus trees using screen-caged thermocouple Psychrometers
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: D.M. Oosterhuis --- Department of Agronomy, U.S.A. M.J. Savage --- Department of Soil Science and Agrometeorology, Republic of South Africa H.H. Wiebe --- Biology Department, U.S.A.Screen-caged thermocouple Psychrometers were used to non-destructively measure the water potential (ψ) in the trunks of mature citrus trees (Citrus sinensis L. Osbeck), and the values compared with the ψ of covered, exposed, and shaded leaves of the same tree... -
Kaliumvaslegging in 'n Arcadia-grond II. Vaslegging in die kleifraksie
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: C.J. Steenkamp --- , Republiek van Suid-Afrika A.A. Theron --- Departement Grond- en Waterboukunde, Republiek van Suid-Afrika J.A. de Bruyn --- Departement Botanie, Republiek van Suid-AfrikaOndersoek is ingestel na die invloed van relatief lae toedienings van kalium, asook drogingstemperatuur, op die vermoë van die kleifraksie van 'n Arcadia-grond, versadig met kalsium of magnesium, om kalium vas te lê. Die verskil in reaksie tussen die behandelings... -
The effect of removing maize surface residue from the seed-row on seedzone temperature, soil water and maize development
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: W. A.J. Berry --- Summer Grain Sub-Centre, Republic of South Africa J.B. Mallett --- Summer Grain Sub-Centre, Republic of South AfricaEarly maize development is generally less rapid in the cooler soils of tillage systems which maintain large amounts of crop residues (stubble) on the soil surface. However, soil water storage tends to increase with increasing amount of surface cover, and... -
The influence of temperature and boron on pollen germination in Mangifera indica L.
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: Esmé de Wet --- , Republic of South Africa P.J. Robbertse --- , Republic of South Africa H.T. Groeneveld --- Department of Statistics/Plant Production, Republic of South AfricaFruit set in the mango (Mangifera indica L.) cultivar ‘Haden’ is exceptionally low. In an effort to determine the reason for this phenomenon, the influences of temperature and application of boron on pollen germination and the effectiveness of cross- versus... -
Effect of temperature during the first 42 days following full bloom on apple fruit growth and size at harvest
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: O. Bergh --- , Republic of South AfricaThe relationship between temperature prevailing during the 42-day period following full bloom (42 DFFB) and fruit size at harvest of four apple cultivars was studied for two seasons. Lower temperatures during the first season resulted in smaller fruit whereas higher... -
Nitrogen mineralization, nitrification and nitrogen balance in laboratory incubation of soil from natural grassland in the central Orange Free State
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: G.H. Wiltshire --- Department of Soil Science, Republic of South AfricaAir-dried soil from three layers under grassveld was moistened by the addition of 12 levels of water and incubated for up to two years at five temperatures in screw-capped preserving jars with an air-filled head- space equivalent to seven times... -
Role of temperature and water potential on the activity of some acetanilide herbicides on three Phaseolus taxa
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: E. van Rensburg --- , Republic of South Africa L.P. van Dyk --- , Republic of South Africa G.H. de Swardt --- , Republic of South AfricaThe effect of three acetanilide herbicides on the hypocotyl-epicotyl growth rate of three Phaseolus taxa was studied at two temperatures and two water potentials. The study proved that, apart from the detrimental effects of the herbicides, low temperature and water... -
A comparison of seed vigour tests for maize (Zea mays L.)
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: H.A. van de Venter --- , Republic of South Africa H.W. Lock --- , Republic of South AfricaA number of seed vigour tests were conducted on two groups of maize seed lots. One group consisted of six seed lots of different cultivars while the other group consisted of six sub-lots of one cultivar, artificially aged for different... -
Inferences on the threshold temperatures and summation constants in the case of crop development
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: A.J. van der Merwe --- Department of Mathematical Statistics, Republic of South AfricaThe simplest crop development model assumes a linear relationship between temperature (x) and rate of development (y) and can be written as y = β1 + β2x + €. In crop development models non-linear functions of the parameters β1 and... -
Refinement and validation of the PUTU wheat crop growth model 3. Grain growth
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: A. Singels --- Department of Agrometeorology, Republic of South Africa J.M. de Jager --- Department of Agrometeorology, Republic of South AfricaA submodel for simulating daily grain growth was incorporated in an existing wheat crop growth model. The submodel calculated daily potential grain growth from green leaf area index, plant population and crop stage. Simulated daily potential grain growth was reduced... -
Minimum nagtemperatuur en groeiseisoenlengte van katoenproduserende gebiede in Suid-Afrika
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: M.C. Dippenaar --- , Republiek van Suid-Afrika J.J. Human --- Departement Agronomie, Republiek van Suid-Afrika'n Bewegende gemiddelde daaglikse minimum nagtemperatuur, T[mbar][nbar] (per vyf dae) is oor 8–15 j vir 23 weer- stasies bereken wat verspreid in die katoenproduserende gebiede van die Republiek van Suid-Afrika aanwesig is. As onderste temperatuurdrempel, of basistemperatuur waarby groei van... -
Effect of temperature on the severity of pre-and post-emergence damping-off and seedling blight of grain sorghum (Sorghum bicolor)
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: N.W. McLaren --- , Republic of South Africa F. H.J. Rijkenberg --- Department of Microbiology and Plant Pathology, Republic of South AfricaThe effect of temperature regimes on seedling diseases of grain sorghum (Sorghum bicolor (L.) Moench), was investigated in growth cabinets and for five planting dates in field trials. The period from planting to seedling emergence was increased by low pre-emergence... -
An attempt at estimating solar radiation at South African sites which measure air temperature only
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: B. S.E. Clemence --- , Republic of South AfricaDaily potential surface radiation values were calculated for selected South African weather stations. These were used, together with various air temperature parameters, to derive regression equations to estimate actual surface solar radiation at sites lacking the required instrumentation. A single... -
Effect of different day and night temperatures on the diurnal growth rate of terminal and lateral fruits in Golden Delicious apple
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: O. Bergh --- , Republic of South Africa DeV. Cloete --- , Republic of South AfricaThe diurnal growth rate of terminal and lateral fruitlets in the same cluster was studied in Golden Delicious under varying night and day temperature conditions In growth chambers as well as in the open. Terminal and lateral fruitlets had a... -
Influence of temperature during the preceding growth period of lucerne on its regrowth at different temperatures
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: P.L. Greenfield --- Department of Agronomy, United States of America Dale Smith --- Department of Agronomy, United States of AmericaOne-year-old lucerne (Medicago sativa L. cv. ‘Vernal’) plants were grown to first flower through three cuttings in three temperature regimes, H (33°C day/24°C night), W (27718°C) and C (21712°C), to ascertain the influence of temperature preceding defoliation on subsequent growth... -
Effect of ridging on the temperature regime of a waterlogged vineyard soil
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: P.A. Myburgh --- , Republic of South Africa J.H. Moolman --- Department of Soil and Agricultural Water Science, Republic of South AfricaWaterlogged conditions in hydromorphic soils during spring cause low temperatures which may restrict grapevine performance. Ridging is a soil preparation method that can improve internal drainage in the root zone. Temperature measurements showed that ridging tended to increase temperatures in... -
Bepaling van optimale blom en plantdatums vir koring in die sentrale besproeiingsgebiede van die RSA met behulp van 'n groeimodel
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: A. Singels --- Departement Landbouweerkunde, Republiek van Suid-AfrikaOptimale blom- en plantperiodes vir besproeiingskoring is bepaal vir 15 lokaliteite in die sentrale besproeiingsgebiede van die RSA deur gebruik te maak van historiese temperatuurdata en die PUTU koringgroeimodel. Die hoogste gemiddelde opbrengs is gesimuleer met blomperiodes wat oor die... -
Verwantskap tussen organiese materiaalinhoud van sekere onversteurde bogronde, grondeienskappe en klimaatsdata in Suid-Afrika
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: M.E. du Toit --- , Republiek van Suid-Afrika C.C. du Preez --- Departement van Grondkunde, Republiek van Suid-AfrikaDie doel met die ondersoek was om vas te stel of die organiese materiaalinhoud van onversteurde ortiese A-horisonte, wat deur rooi apedale, geelbruin apedale en sagte plintiese B-horisonte onderlê word, vanaf beskikbare of maklik meetbare grondeienskappe en klimaatsdata bereken kan... -
Effects of sample drying temperature on indices of available nitrogen in soils
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: G.H. Wiltshire --- Department of Soil Science, Republic of South Africa C.C. du Preez --- Department of Soil Science, Republic of South AfricaDuring a field trial investigation into the long-term effects of conservation practices on the nitrogen fertility of a soil cropped annually to wheat, it was observed that sample preparation had an effect on some indices of available nitrogen. The trial... -
The effect of oven-drying on residual inorganic nitrogen in soils
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: G.H. Wiltshire --- Department of Soil Science, Republic of South Africa C.C. du Preez --- Department of Soil Science, Republic of South AfricaResidual ammonium nitrogen in soils which were dried in an oven increased, whereas residual nitrate nitrogen remained almost constant. This observation led to experiments which help to explain the accumulation of ammonium nitrogen in oven-dried soils. It was found that... -
The effect of a diurnal period of supra-optimal temperature on the seed vigour of sunflower
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: A.A. Nel --- , Republic of South AfricaThe daily maximum temperature in the upper 20 mm of sandy soils is often higher than 45°C on cloudless days during November, December and January in the summer rainfall region of South Africa. At these supra-optimal temperatures, sunflower seedling vigour... -
An explanation of genotype by environment interaction for maize in South Africa
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: M.C. Laubscher --- , Republic of South Africa C.Z. Roux --- Department of Genetics, Republic of South Africa J. M.P. Geerthsen --- Department of Genetics, Republic of South AfricaThe causes of genotype interaction with the environment was investigated using AMMI (Additive Main Effects and Multiplicative Interaction) analysis. AMMI quantified environments by means of E_IPCA1 (first principal component analysis for environment) such that it was highly significantly correlated (r... -
Use of solid waste bagasse from a paper mill as an organic amendment and its effect on some soil properties: a case study
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: J.C. Hughes --- Soil Science, South Africa S. J.A. Girdlestone --- Soil Science, South AfricaAt a paper mill in KwaZulu-Natal, South Africa bagasse waste was disposed of by burying it in a layer resulting in variable sugar cane growth. The waste was mostly organic fibres, had a high water holding capacity, and contained small... -
Changes in chemical properties and temperature during the degradation of organic wastes subjected to simple composting protocols suitable for small-scale farming, and quality of the mature compost
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: D.C. Smith --- , South Africa J.C. Hughes --- , South AfricaDespite the high cost of chemical fertilizers and pesticides, composting is not widely practiced in many rural communities in South Africa. To demonstrate the simplicity and benefit of composting, four composting protocols were selected, based on technology and resources available... -
Optimum temperature and inoculation levels for in vitro production of Pratylenchus brachyurus on carrot discs
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: H. Fourie --- , South Africa G.A. Venter --- , South Africa A.H. Mc Donald --- , South AfricaPratylenchus brachyurus is an economically important parasite of several agricultural crops, including potato, groundnut, maize and soybean. Large numbers of this species are required for research on pathogenecity, host plant resistance and efficacy of nematicides. The effect of inoculation density... -
Effect of temperature on the germination of grain Amaranth
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: T.A. Loonat --- Department of Agriculture, Conservation, Environment and Land Affairs (Gauteng), South Africa E. van den Heever --- , South Africa P. Hammes --- Department of Plant Production and Soil Science, South AfricaAmaranthus cultivation in South Africa has potential commercial importance. To make optimal use of the growing season planting under cool soil conditions is often necessary. The effect of temperature on seed germination of A. hypochondriaeus (unknown landrace) and A. cruentus,... -
Germination strategies of Strandveld Succulent Karoo plant species for revegetation purposes: III Effect of relative humidity and storage site on seed viability
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: A.J. de Villiers --- Department of Botany, Republic of South Africa M.W. van Rooyen --- Department of Botany, Republic of South Africa G.K. Theron --- Department of Botany, Republic of South AfricaChanges in seed viability owing to fluctuations in environmental conditions (temperature and relative humidity) are crucial factors to consider during post-mining revegetation efforts in the Strandveld Succulent Karoo. The effect of relative humidity and storage site on seed viability was... -
The characterization of Pythium group G occurring on kenaf in South Africa
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: M.T. Tesfaendrias --- Department of Plant Sciences, South Africa W.J. Swart --- Department of Plant Sciences, South Africa W. Botha --- , South AfricaKenaf provides a source of high quality cellulose fibers and its cultivation is being investigated in South Africa with a view to commercial production. In March 2001, kenaf plants in experimental plots near Bloemfontein, South Africa, developed large, black sunken... -
Effect of temperature, soil moisture content and type of cutting on establishment of sweet potato cuttings
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: T. Belehu --- Department of Plant Production and Soil Science, Republic of South Africa P.S. Hammes --- Department of Plant Production and Soil Science, Republic of South AfricaEffective rooting is essential for successful crop establishment from cuttings. The objective of this study was to determine the effect of temperature and soil water content on the root and shoot growth during the early establishment of sweet potato cuttings... -
Suitability of two types of plastic covering on mini-tunnels for paprika seedling production in warm areas
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: J. Allemann --- , Republic of South Africa J. Viljoen --- , Republic of South Africa J.G. Niederwieser --- , Republic of South AfricaA trial was conducted at the ARC-Roodeplaat Vegetable and Ornamental Plant Institute to determine the difference between the two types of plastic (clear and opaque) used as covering for mini-tunnels during paprika (Capsicum anuum L.) seedling production. Two cultivars (PapriKing... -
The effect of temperature on the germination of six selected weed species
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: MarthaM. Manoto --- Department of Agriculture: Western Cape, Republic of South Africa MI. Ferreira --- Department of Agriculture: Western Cape, Republic of South Africa GA Agenbag --- Department of Agronomy, Republic of South AfricaField-collected seeds were incubated in a germination cabinet at three temperature regimes and germination percentage was determined after incubation. Species such as Arctotheca calendula, Avena fatua, Bromus diandrus and Raphanus raphanistrum germinated best when subjected to a diurnal temperature regime... -
Estimation of frost occurrence and duration of frost for a short-grass surface
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: MJ Savage --- Agrometeorology Discipline, Soil-Plant-Atmosphere Continuum Research Unit, School of Agricultural, Earth and Environmental Sciences, South AfricaThe estimation of frost duration (FD) was investigated using dielectric, infrared surface temperature and grass temperature subhourly measurements. Near real-time FD data and information displays and alerts were also made available via a web-based system. FD was estimated using a... -
Estimation of leaf wetness duration for a short-grass surface
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: MJ Savage --- Agrometeorology Discipline, Soil-Plant-Atmosphere Continuum Research Unit, South AfricaThe measurement of leaf wetness duration (LWD) was investigated using subhourly dielectric, infrared surface temperature, dewpoint temperature, grass temperature and relative humidity (RH) measurements. Near real-time LWD data and information displays and alerts were made available timeously via a web-based... -
Effects of storage conditions on transpiration rate of pomegranate aril-sacs and arils
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: Wilhelmina V Aindongo --- Department of Food Science, Faculty of AgriSciences, South Africa Oluwafemi J Caleb --- Postharvest Technology Research Laboratory, South African Research Chair in Postharvest Technology, Faculty of AgriSciences, South Africa Pramod V Mahajan --- Department of Horticultural Engineering, Germany Marena Manley --- Department of Food Science, Faculty of AgriSciences, South Africa Umezuruike L Opara --- Postharvest Technology Research Laboratory, South African Research Chair in Postharvest Technology, Faculty of AgriSciences, South AfricaThis study investigated the effects of temperature (5, 10, 15 and 22 °C) and relative humidity (RH) (76%, 86% and 96%) on the transpiration rate (TR) of pomegranate (Punica granatum L.) cv. Bhagwa fruit fractions, namely arils and aril-sac. Both... -
THE EFFECT OF TEMPERATURE ON SPECIFIC GROWTH RATE AND ACTIVATION ENERGY OF MICROCYSTIS AND SYNECHOCOCCUS ISOLATES RELEVANT TO THE ONSET OF NATURAL BLOOMS
Item type: Journal Article • Journal: Journal of the Limnological Society of Southern Africa • Authors: G. H.J. Krüger --- Department of Botany, South Africa J.N. Eloff --- Department of Botany, South AfricaTo investigate the correlation between temperature and the appearance of Microcystis blooms in nature, the effect of temperature on the growth of four Microcystis izolates (two toxic and two non-toxic) was investigated. The lower temperature limit for Microcystis varied between... -
EARLY OBSERVATIONS ON SOME LIMNOLOGICAL CHARACTERISTICS OF THREE ORANGE FREE STATE IMPOUNDMENTS
Item type: Journal Article • Journal: Journal of the Limnological Society of Southern Africa • Authors: J.U. Grobbelaar --- , South AfricaThe first limnological investigations on three impoundments in the Orange Free State are described. No thermal stratification was found and water temperatures below 8,6°C were not measured. The waters were turbid and the unfavourable underwater light climate was the major... -
POPULATION DYNAMICS AND DEMOGRAPHY OF AN ESTUARINE COPEPOD (PSEUDODIAPTOMUS EESSEI) IN LAKE SIBAYA, A SUBTROPICAL FRESHWATER COASTAL LAKE
Item type: Journal Article • Journal: Journal of the Limnological Society of Southern Africa • Authors: RC Hart --- , South AfricaPopulation size and stage structure of Pseudodiaptomus hessei (Mrázek) was studied over 27 months at a single site in subtropical Lake Sibaya. Population density varied seasonally from about 1 to 4 individuals per litre, but a fairly stable population structure... -
THE TEMPERATURE-GROWTH RATE RELATIONSHIPS OF AEROBIC HETEROTROPHIC BACTERIA ISOLATED FROM A SILT-LADEN IMPOUNDMENT
Item type: Journal Article • Journal: Journal of the Limnological Society of Southern Africa • Authors: D.F. Toerien --- , South AfricaThe temperature-growth rate responses of bacterial isolates from Wuras Darn, a silt-laden, highly turbid impoundment were described well by Arrhenius equations. Activation energies varied from 10, 15 to 29, 59 kcal moles−1, indicating a varied response to temperature changes. Since... -
PREDICTION OF SURFACE WATER TEMPERATURE OF SOUTH AFRICAN IMPOUNDMENTS
Item type: Journal Article • Journal: Journal of the Limnological Society of Southern Africa • Authors: D.J. van Schalkwyk --- Department of Mathematical Statistics, Republic of South Africa R.D. Walmsley --- Department of Plant Schiences, Republic of South AfricaTemperature data for 18 South African impoundments were evaluated against Straskraba's global surface water predictive model. All impoundments exhibited quantifiable sinusoidal annual temperature variations which allowed for good predictive capabilities using Straskraba's empirical approach. For each impoundment coefficients for input... -
A PRELIMINARY ASSESSMENT OF THE IMPACT OF SOME ASPECTS OF THE HARTBEESPOORT DAM ENVIRONMENT ON PRODUCTION OF THE MAJOR FISH SPECIES
Item type: Journal Article • Journal: Journal of the Limnological Society of Southern Africa • Authors: K.L. Cochrane --- , South AfricaThe dominant species of fish in Hartbeespoort Dam, in terms of mass composition of catches, are shown to be Oreochromis mossambicus (Peters), Cyprinus carpio Linnaeus and Clarias gariepinus Burchell. Minimum winter temperatures are demonstrated to have a major impact on... -
EFFECT OF PROGRAMMED CIRCADIAN TEMPERATURE FLUCTUATIONS ON POPULATION DYNAMICS OF BULINUS TROPICUS (KRAUSS) AND LYMNAEA NATALENSIS KRAUSS (GASTROPODA: MOLLUSCA)
Item type: Journal Article • Journal: Journal of the Limnological Society of Southern Africa • Authors: K.N. de Kock --- Department of Zoology, South AfricaUntil now all life-table studies on Bulinus tropicus (Krauss) and Lymnaea natalensis Krauss involving temperature as the variable factor have been conducted at constant temperatures. This study evaluates the effect of programmed, circadian temperature fluctuations, ranging from 18 to 28... -
THE EFFECT OF CONSTANT TEMPERATURES ON THE HATCHING OF EGGS AND SURVIVAL OF THE FRESHWATER SNAIL BIOMPHALARIA GLABRATA (SAY)
Item type: Journal Article • Journal: Journal of the Limnological Society of Southern Africa • Authors: P.H. Joubert --- South African Medical Research Council and Department of Zoology, South Africa S.J. Pretorius --- South African Medical Research Council and Department of Zoology, South AfricaThe incubation period and percentage hatching of eggs of pigmented and unpigmented Biomphalaria glabrata at constant temperatures were investigated in the range 14 °C to 34 °C. In order to determine the influence of extreme temperatures on adult snails, specimens... -
EFFECT OF CONSTANT TEMPERATURE ON POPULATION DYNAMICS OF BULINUS TROPICUS (KRAUSS) AND LYMNAEA NATALENSIS KRAUSS
Item type: Journal Article • Journal: Journal of the Limnological Society of Southern Africa • Authors: K.N. de Kock --- Snail Research Unit of the South African Medical Resesrch Council, South Africa J.A. van Eeden --- Snail Research Unit of the South African Medical Resesrch Council, South AfricaLife-tables were compiled for cohorts of the two freshwater snail species Bulinus tropicus (Krauss) and Lymnaea natalensis Krauss at six different constant temperatures from 17 to 32 °C under identical conditions of crowding, feeding and chemical composition of the water... -
OBSERVATIONS ON THE DISTRIBUTION, EMERGENCE AND BEHAVIOUR OF CENTRAL AFRICAN CHAOBORIDAE
Item type: Journal Article • Journal: Journal of the Limnological Society of Southern Africa • Authors: SA Mitchell --- Unit for Limnology, South AfricaThe distribution of four species of Chaoboras over selected parts of Zimbabwe is given. The effect of temperature on the duration of the larval life cycle is discussed in relation to the generation time and the lunar periodicity of the... -
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... -
MASS MORTALITIES OF FISH IN SOUTH AFRICAN ESTUARIES
Item type: Journal Article • Journal: Southern African Journal of Aquatic Sciences • Authors: A.K. Whitfield --- , South AfricaChanges to the physico-chemical environment have been identified as the cause of fish mass mortalities in South African estuaries. Most published accounts have linked these mortalities to a single dominant factor such as low salinity, low or high temperature, low... -
WATER TEMPERATURE AND THE 1987 FISH KILL AT LAKE ST LUCIA ON THE SOUTH EASTERN COAST OF AFRICA
Item type: Journal Article • Journal: Southern African Journal of Aquatic Sciences • Authors: D.P. Cyrus --- Coastal Research Unit of Zululand, Department of Zoology, South Africa S. McLean --- Coastal Research Unit of Zululand, Department of Zoology, South AfricaAn unusually cold spell during the winter of 1987 caused a drop in water temperature at Lake St Lucia. This coupled with typical estuarine salinities in the lake resulted in a fish kill. The kill was one of the largest... -
Fire and the dynamics of a semi-arid grassland: influence on soil characteristics
Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: H A SnymanThe short-term impact of fire burning with the wind (head fire) and against the wind (back fire) on soil characteristics (soil-water content, soil compaction, soil temperature, organic matter, pH, exchangeable Ca, Mg, K, Na and extractable P) were determined in... -
Soil seed bank evaluation and seedling establishment along a degradation gradient in a semi-arid rangeland
Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: HA SnymanThe effects of rangeland degradation on the size and species composition of the seed bank and seedling establishment in the field were quantified over a two year period (2000–2001 and 2001–2002 growing seasons). Soil seed bank sampling was carried out... -
Short-term response of burnt grassland to defoliation in a semi-arid climate of South Africa
Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: HA SnymanThe impact of defoliation on the productivity and soil temperature of burnt grassland (head and back fires) was investigated over the short term (one and two growing seasons after burning). Head fires had greater flame height and rate of spread... -
Detecting the onset of rangeland degradation using soil respiration and boundary lines: preliminary findings from the Nama Karoo
Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: A Mills --- Department of Soil Science, South Africa M Fey --- School of Earth and Environment, Australia B Kgope --- , South Africa J Donaldson --- , South Africa J de W Bosenberg --- , South AfricaMean annual soil respiration correlates with net primary productivity and therefore provides an indication of ecosystem functioning. Soil respiration, however, varies considerably in space and time owing to the influence of factors such as soil nutrient content, temperature and water... -
The sublethal effects of zinc at different water temperatures on selected haematological variables in Oreochromis mossambicus
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: PP Buthelezi V Wepener DP CyrusTrace metals such as zinc play an important role in the normal metabolic functioning of all organisms. However, metals can become toxic if background concentrations are exceeded in the environment. This study investigated the sublethal effects of zinc on the... -
Physical determinants of the distribution and abundance of the burrowing ocypodid crab Paratylodiplax blephariskios Stebbing in the St. Lucia and Mhlathuze estuaries, KwaZulu-Natal, South Africa
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: RK Owen AT Forbes DP Cyrus SE PiperThe burrowing ocypodid crab, Paratylodiplax blephariskios, is endemic to the southeast coast of southern Africa where it forms an important component of the estuarine benthic fauna in muddy substrata. Two estuaries in KwaZulu-Natal, namely St. Lucia and the Mhlathuze, were... -
Modelling highly variable daily maximum water temperatures in a perennial South African river system
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: NicholasA Rivers-Moore CarelN Bezuidenhout GrahamPW JewittThirty-three months of observed hourly water temperatures were used to calculate daily maximum water temperatures for nine sites within the Sabie-Sand River system, Mpumalanga Province, South Africa. A suite of statistical models for simulating daily maximum water temperatures, of differing... -
Seasonal and diurnal stratification in two small Zimbabwean reservoirs
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: Tamuka Nhiwatiwa BrianE MarshallSeasonal and diurnal stratification patterns were studied in two small Zimbabwe reservoirs. The water level of the upper reservoir fluctuated more than that of the lower one and theoretical water retention times were 9 days and 3.6 days, respectively. Rainfall... -
Salinity tolerance of the burrowing ocypodid crab, Paratylodiplax blephariskios, in the St. Lucia and Mhlathuze estuaries, KwaZulu-Natal, South Africa
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: RK Owen --- Department of Zoology, South Africa AT Forbes --- , South AfricaThe ocypodid crab, Paratylodiplax blephariskios, is endemic to the southeast coast of southern Africa where it forms an important component of the estuarine benthic fauna in muddy substrata. The St. Lucia and Mhlathuze estuaries are two of the largest estuaries... -
A short note on factors affecting the geographic distribution of the burrowing ocypodid crab, Paratylodiplax blephariskios: temperature, habitat and competition
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: RK Owen --- Department of Zoology, South AfricaThe known distribution of Paratylodiplax blephariskios extends from the Morrumbene estuary in Mozambique to the Mngazana estuary in the Eastern Cape. Laboratory data on the temperature tolerance of P. blephariskios indicated that the crab could survive temperatures between 12.5°C and... -
Distribution of Nile perch Lates niloticus in southern Lake Victoria is determined by depth and dissolved oxygen concentrations
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: PC Goudswaard --- , the Netherlands EFB Katunzi --- , Tanzania JH Wanink --- , the Netherlands F Witte --- , the NetherlandsAlthough Nile perch Lates niloticus is assumed to be sensitive to low oxygen concentrations, it was found in deep water in Lake Victoria, where oxygen depletion is common during the rainy season. Since factors determining Nile perch distribution are not... -
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... -
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... -
Climatic and Altitudinal Criteria for Commercial Afforestation with Special Reference to Natal
Item type: Journal Article • Journal: South African Forestry Journal • Authors: A. P.G. Schönau --- Wattle Research Institute and Department of Agricultural Engineering, South Africa R.E. Schulze --- Wattle Research Institute and Department of Agricultural Engineering, South AfricaCriteria of altitude and climate such as mean annual precipitation, mean annual. January and July temperatures, mean daily maximum and minimum temperatures for January and July respectively and duration of soil moisture deficit are given for five main commercial tree... -
8. A Different Approach to Site Evaluation and Some Preliminary Results
Item type: Journal Article • Journal: South African Forestry Journal • Authors: A. P.G. Schönau --- , R.C. Purnell --- de Wet Forestry Research Centre,This paper describes a new approach towards site evaluation of exotic tree species which have a limited and non-representative occurrence. Instead of applying the classical site factor analysis and measuring a considerable number of sample plots of different ages at... -
Factors Affecting the Timing of Grassland Regrowth after Fire in the Montane Grasslands of Natal
Item type: Journal Article • Journal: South African Forestry Journal • Authors: C.S. Everson --- , South Africa TheresaM. Everson --- , South AfricaRecent research has indicated that burning Highland Sourveld once growth has been initiated increases grass tiller mortality. Present burning prescriptions could therefore be improved by an insight into the factors controlling the initiation of grass growth in spring. It was... -
Climatology and Variability of Sea Surface Temperature and Surface Chlorophyll in the Benguela and Agulhas Ecosystems As Observed by Satellite Imagery
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: H. Demarcq R. G. Barlow F. A. ShillingtonA climatology of satellite-derived sea surface semperature (SST) and surface chlorophyll a concentration (Chl), and their associated variability at time-scales from weeks to years, was constructed for the Benguela and Agulhas ecosystems. Global area coverage data at 4.5 km spatial... -
Oceanic variability in the western sector of Algoa Bay, South Africa
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: EH Schumann JRS Churchill HJ ZaaymanThe city of Port Elizabeth lies in the western sector of Algoa Bay, and a number of projects have investigated the oceanic temperature, salinity and current structures in the vicinity. This paper analyses past results, and then incorporates measurements of... -
Seasonal variation in phytoplankton in the southern Benguela: pigment indices and ocean colour
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: R Barlow H Sessions M Balarin S Weeks C Whittle L HutchingsPigment indices and satellite imagery were used to investigate the seasonal variation in phytoplankton in the southern Benguela, with the aid of monthly monitoring on two transect lines. Sea surface temperature images revealed the similarity in thermal conditions during autumn,... -
Pigment signatures of phytoplankton composition in the northern Benguela ecosystem during spring
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: R Barlow D Louw M Balarin J AlheitPigment indices were used to investigate the distribution and composition of phytoplankton in the northern Benguela during the austral spring of 2000, with sampling being conducted on five transect lines between 19°S and 25°S and at other inshore stations on... -
Remotely sensed variability of temperature and chlorophyll in the southern Benguela: upwelling frequency and phytoplankton response
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: SJ Weeks R Barlow C Roy FA ShillingtonHigh-resolution (1km) satellite data from the NOAA AVHRR (Advanced Very High Resolution Radiometer) and OrbView-2 SeaWiFS (Sea-viewing Wide Field-of-view Sensor) are used to investigate the upper layer dynamics of the southern Benguela ecosystem in more detailed space and time scales... -
Coastal currents and temperatures along the eastern region of Algoa Bay, South Africa, with implications for transport and shelf–bay water exchange
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: MJ Roberts --- Department of Environmental Affairs, South AfricaBoat ADCP surveys and an eight-month deployment of a 1 200 kHz ADCP were used to study the nearshore (5–25 m depth) current and temperature patterns along the eastern coastal region of Algoa Bay, on the south-east coast of South... -
South African kelp moving eastwards: the discovery of Ecklonia maxima (Osbeck) Papenfuss at De Hoop Nature Reserve on the south coast of South Africa
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: JJ Bolton --- Botany Department and Marine Research Institute, South Africa RJ Anderson --- Botany Department and Marine Research Institute, South Africa AJ Smit --- School of Biological and Conservation Sciences, Faculty of Science, South Africa MD Rothman --- Botany Department and Marine Research Institute, South AfricaHistorical and recent evidence is documented to demonstrate that the eastern limit of the major kelp-bed forming seaweed Ecklonia maxima has moved c. 73 km eastward along the south coast of South Africa since 2006, after remaining unchanged for almost... -
Thermal constraints on the respiration and excretion rates of krill, Euphausia hanseni and Nematoscelis megalops, in the northern Benguela upwelling system off Namibia
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: T Werner --- , Germany K Huenerlage --- , Germany H Verheye --- Oceans and Coasts, Department of Environmental Affairs, South Africa F Buchholz --- , GermanyRates of respiration and ammonia excretion of Euphausia hanseni and Nematoscelis megalops were determined experimentally at four temperatures representative of conditions encountered by these euphausiid species in the northern Benguela upwelling environment. The respiration rate increased from 7.7 µmol O2... -
Upwelling and ocean structures off Algoa Bay and the south-east coast of South Africa
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: WS Goschen --- South African Environmental Observation Network (SAEON), South Africa EH Schumann --- Department of Geosciences, South Africa KS Bernard --- South African Environmental Observation Network (SAEON), South Africa SE Bailey --- South African Environmental Observation Network (SAEON), South Africa SHP Deyzel --- South African Environmental Observation Network (SAEON), South AfricaAs the Agulhas Current flows along the south-east coast of South Africa, a number of processes operate that bring cold, deep water up onto the narrow shelf. As a consequence, upwelling along the coastline is enhanced farther southward and downstream... -
Stock-environment recruitment analysis for Namibian Cape hake Merluccius capensis
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: P Kainge --- National Marine Information and Research Centre, Namibia N Bahamon --- Centre d'Estudis Avançats de Blanes (CEAB-CSIC), Spain CH Bartholomae --- National Marine Information and Research Centre, Namibia JN Kathena --- National Marine Information and Research Centre, Namibia AK van der Plas --- National Marine Information and Research Centre, Namibia A Gordoa --- Centre d'Estudis Avançats de Blanes (CEAB-CSIC), SpainThe factors modulating recruitment success of Cape hake Merluccius capensis in Namibian waters are still unresolved. In this study, we used generalised additive models, regression tree analysis and the conventional Ricker model to examine the effect of environmental indices and... -
The effect of bottom heat on rooting Pinus patula and Pinus elliottii x Pinus caribaea stem cuttings in South Africa
Item type: Journal Article • Journal: The Southern African Forestry Journal • Authors: R.G. Mitchell --- Sappi Forests Research, South AfricaFive trials, testing the effect ofbottom heat on rooting, were set between January 1995 and December 1996 on P. patula and P. elliottii x P. caribaea cuttings as a method of improving root strike. In four out of five trials... -
A stratification of the South African forestry landscape based on climatic parameters
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: JH Louw --- School of Natural Resource Management, South Africa I Germishuizen --- , South Africa CW Smith --- Paperbark Forestry Consulting, South AfricaThe benefits of high-resolution forest site classification systems have been widely acknowledged in South Africa as a prerequisite for decision-making in forestry management. Although substantial research and development work have been done on categorising and mapping the soil and geological... -
Temporal trends in total phosphorus, temperature, oxygen, chlorophyll a and phytoplankton populations in Hartbeespoort Dam and Roodeplaat Dam, South Africa, between 1980 and 2000
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: CarinE van Ginkel MichaelJ SilberbauerEutrophication, phytoplankton blooms and changes to the phytoplankton composition are some of the problems facing the managers of Hartbeespoort Dam and Roodeplaat Dam. Trends, both decreasing and increasing, are visible in the phosphorus concentrations, temperatures, dissolved oxygen concentrations and chlorophyll... -
Remediation of eutrophic water using Lemna minor in a controlled environment
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: AA Ansari FA KhanThe growth response of common duckweed Lemna minor was studied at various temperature and pH levels for its possible application for remediating eutrophic waters. The dry weight, chlorophyll a, nitrogen, phosphorus, potassium, peroxidase (POD), catalase (CAT) and malondialdehyde (MDA) levels... -
Photosynthetic differences between Microcystis aeruginosa and Oscillatoria simplicissima in relation to species succession in the Vaal River, South Africa
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: A Venter --- School of Environmental Sciences and Development (Botany Division), S du Plessis --- School of Environmental Sciences and Development (Botany Division), PDR van Heerden --- School of Environmental Sciences and Development (Botany Division), AJ Strauss --- School of Environmental Sciences and Development (Botany Division), J Bezuidenhout --- School of Environmental Sciences and Development (Botany Division),In 1991 Oscillatoria simplicissima replaced Microcystis aeruginosa in the Vaal River, South Africa. This study explored the reason for this succession by looking at the photosynthetic performance of these two cyanoprokaryotes at different temperatures, light intensities and N:P ratios. Microcystis... -
Diel vertical migration of anchovy Engraulis encrasicolus larvae in the northern Benguela
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: EK Stenevik S Sundby R CloeteThe diel vertical migration of anchovy Engraulis encrasicolus larvae was studied in the northern Benguela during a survey in April 2001. The diel pattern is described in relation to the degree of swimbladder inflation and the vertical structure of temperature... -
Short-term variability in alongshore winds and temperature off Swakopmund, Namibia, during a non-upwelling event in 1998–1999
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: CH Bartholomae E HagenSwakopmund is a popular coastal resort in Namibia, especially during the summer holiday season when daily sea temperatures can fluctuate several degrees in a short period. Hourly measurements of the near-bottom water temperature were collected off the Swakopmund Jetty to... -
Towards the development of environmental indices for the Namibian shelf, with particular reference to fisheries management
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: CH Bartholomae AK van der PlasThe Namibian Ministry of Fisheries and Marine Resources has the task of collecting and providing relevant oceanographic information for management of their fisheries. However, quality information is difficult to provide because of the complexity of the processes involved in the... -
Application of a chlorophyll index derived from satellite data to investigate the variability of phytoplankton in the Benguela ecosystem
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: H Demarcq R Barlow L HutchingsThe spatial and temporal variability in phytoplankton biomass in the Benguela ecosystem was investigated over an 8-year period using a chlorophyll index (Chl Index) derived from low resolution SeaWiFS ocean colour data. Monthly composite images revealed that the surface chlorophyll... -
Comparative ecology of the copepods Calanoides carinatus and Calanus agulhensis — the influence of temperature and food
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: JA Huggett AJ Richardson JG FieldHypotheses regarding temperature, food abundance and food size were tested to explore niche separation between Calanoides carinatus, an abundant copepod in the cool and food-rich southern Benguela upwelling system, and Calanus agulhensis, the dominant copepod on the warmer, relatively food-poor... -
Population structure and growth of polydorid polychaetes that infest cultured abalone Haliotis midae
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: CA Simon AJ BoothPolydorid polychaetes can infest cultured abalone thereby reducing productivity. In order to effectively control these pests, their reproductive biology must be understood. The population dynamics and reproduction of polydorids infesting abalone Haliotis midae from two farms in South Africa is... -
Temperature preference of juvenile dusky kob Argyrosomus japonicus (Pisces: Sciaenidae)
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: A Bernatzeder PJ BritzThe final temperature preference of cultured juvenile dusky kob is determined to provide an indicator of their optimum temperature for growth. Trials were conducted over a five-day period in horizontal temperature gradients ranging from 21°C to 27°C. Control trials were... -
Primary production in the Benguela ecosystem, 1999–2002
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: R Barlow T Lamont B Mitchell-Innes M Lucas S ThomallaPhytoplankton production was investigated throughout the whole Benguela ecosystem in winter 1999 and in summer 2002 during two four-week research cruises from Cape Town, South Africa, through Namibian waters to Namibe in southern Angola. Primary production ranged from 0.14–2.26 g... -
Salinity tolerance of the South African endemic amphipod Grandidierella lignorum (Amphipoda: Aoridae)
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: NF Masikane --- School of Life Sciences, South Africa BK Newman --- Coastal Systems Research Group, Natural Resources and the Environment, South Africa UM Scharler --- School of Life Sciences, South AfricaThe endemic amphipod Grandidierella lignorum is an organism potentially suited to the toxicity testing of coastal water and sediment in South Africa. The ranges of salinity and temperature at which G. lignorum can be used for toxicity testing were investigated... -
Climate change impact on the limnology of Lake Kariba, Zambia–Zimbabwe
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: TS Mahere --- Department of Biological Sciences, Zimbabwe MZ Mtsambiwa --- University of Zimbabwe Lake Kariba Research Station, Zimbabwe PC Chifamba --- Department of Biological Sciences, Zimbabwe T Nhiwatiwa --- Department of Biological Sciences, ZimbabweThere is evidence that global warming is changing the thermal regimes of tropical lakes and this paper examines the impact of warming on the limnology of Lake Kariba. Between 1986 and 2011 the mean temperature of the lake rose by... -
Insertion of a temperature probe into the ProSeal® laryngeal mask airway drainage tube
Item type: Journal Article • Journal: Southern African Journal of Anaesthesia and Analgesia • Authors: M Singh --- Department of Anaesthesiology, India D Kapoor --- Department of Anaesthesiology, IndiaBackground: Temperature monitoring is one of the minimum mandatory monitoring standards of anaesthesiology. Intraoperative hypothermia and hyperthermia can both be detrimental for patients. We introduced a temperature probe into a Proseal® laryngeal mask airway (LMA) drainage tube, and measured patient... -
Effectiveness of low-dose midazolam plus ketamine in the prevention of shivering during spinal anaesthesia for emergency lower limb surgery
Item type: Journal Article • Journal: Southern African Journal of Anaesthesia and Analgesia • Authors: K Misiran --- Department of Anaesthesiology and Intensive Care, Faculty of Medicine, Malaysia FZ Aziz --- Department of Anaesthesia and Intensive Care, MalaysiaObjective: This study was conducted to compare the effectiveness of two different dosages of intravenous midazolam in combination with ketamine in the prevention of shivering during spinal anaesthesia for emergency lower limb surgery. -
Microclimate conditions in ventilated wet-walled greenhouses in a subtropical climate: spatial variability
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: Michael J Savage --- Agrometeorology Discipline, Soil-Plant-Atmosphere Continuum Research Unit, School of Agricultural, Earth and Environmental Sciences, South AfricaSpatial variations of microclimatic conditions in enclosed north–south (N–S) oriented single-arched greenhouse polycarbonate structures, with a wet-wall providing evaporative cooling at the S end, were investigated and displayed online in near real-time. Temperature-controlled fans at the N end extracted air... -
Larval development reflects biogeography in two formerly synonymised southern African coastal crabs
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: I Papadopoulos --- Molecular Zoology Laboratory (Aquatic Division), Department of Zoology, South Africa PR Teske --- Molecular Zoology Laboratory (Aquatic Division), Department of Zoology, South AfricaThe southern African crab Hymenosoma orbiculare was recently split into five distinct species, of which three are estuarine/coastal and have peripatric distributions that are linked to temperature-defined marine bioregions. This suggests that the species’ ranges may be limited by physiological... -
The effect of bacterial-based biofertilisers and cytokinin on the emergence of sunflower at non-limiting and supra-optimal temperatures
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: Andries A Nel --- Agricultural Research Council–Grain Crops Institute, South AfricaSubsurface sunflower (Helianthus annuus L.) seedling growth often deteriorates on sandy-textured soils due to supra-optimal temperature levels on the Highveld area of South Africa leading to poor emergence and suboptimum plant population densities. It has been shown that seedling growth... -
Temporal and spatial variability in the abundance, biomass and distribution of Palaemon peringueyi (Decapoda: Crustacea) are influenced by biological but not physico-chemical factors in the permanently open Kariega Estuary, South Africa
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: NP Nyalungu --- South African National Parks, Cape Research Centre, South Africa AN Hodgson --- Department of Zoology and Entomology, South Africa PW Froneman --- Department of Zoology and Entomology, South Africa M Dopolo --- South African National Parks, Cape Research Centre, South Africa M Masubelele --- South African National Parks, Cape Research Centre, South AfricaBiological and physico-chemical factors affecting abundance and biomass of shrimp Palaemon peringueyi were investigated in 2010–2011 in the lower, middle and upper reaches of the freshwater-deprived permanently open Kariega Estuary. Shrimp abundance and biomass ranged from 0 to 88 ind... -
First report of an Anabaena Bory strain containing microcystin-LR in a freshwater body in Africa
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: PJ Oberholster --- CSIR Natural Resources and the Environment, South Africa S Jappie --- Department of Genetics, South Africa PH Cheng --- CSIR Natural Resources and the Environment, South Africa AM Botha --- Department of Genetics, South Africa MW Matthews --- Marine Remote Sensing Unit, South AfricaIn South Africa, little is known about the production of microcystin by the genus Anabaena Bory. In April 2012, during a cyanobacterial bloom event in Theewaterskloof Dam, Western Cape province, the plankton was sampled on 10 occasions. The dominant algae... -
The influence of selected environmental parameters on the distribution of the dominant demersal fishes in the Kariega Estuary channel, South Africa
Item type: Journal Article • Journal: African Zoology • Authors: Naomi Richardson --- Department of Ichthyology and Fisheries Science, South Africa Alan K. Whitfield --- South African Institute for Aquatic Biodiversity, South Africa Angus W. Paterson --- South African Institute for Aquatic Biodiversity, South AfricaThe Kariega Estuary channel was sampled using an otter trawl and the demersal fish catch analysed using the PRIMER statistical package. A biological-environmental (BIOENV) analysis was undertaken using the catch per unit effort ichthyofaunal data from the spring/summer period of... -
Thermoregulation under semi-natural conditions in speckled mousebirds: the role of communal roosting
Item type: Journal Article • Journal: African Zoology • Authors: Andrew E. McKechnie --- School of Biological and Conservation Sciences, University of KwaZulu-Natal, South Africa Gerhard Körtner --- School of Biological and Conservation Sciences, University of KwaZulu-Natal, South Africa Barry G. Lovegrove --- School of Biological and Conservation Sciences, University of KwaZulu-Natal, South AfricaMousebirds (Coliiformes) exhibit well-developed communal roosting behaviour as well as a pronounced capacity for facultative hypothermic responses. We recorded body temperature (Tb)) in speckled mousebirds (Colius striatus) under semi-natural conditions in outdoor aviaries, and examined interactions between behavioural and metabolic... -
Sexual disparity in activity patterns and time budgets of angulate tortoises (Chersina angulata) on Dassen Island, South Africa
Item type: Journal Article • Journal: African Zoology • Authors: Toby Keswick --- Department of Biodiversity and Conservation Biology, South Africa Brian T. Henen --- Department of Biodiversity and Conservation Biology, South Africa Margaretha D. Hofmeyr --- Department of Biodiversity and Conservation Biology, South AfricaBehavioural frequencies and time budgets for male and female Chersina angulata were recorded in spring, September 2004. The daily activity of the population was 10.51 ± 0.42 h (mean ± CI), but individual males and females were in the open... -
The incidence of torpor in winter and summer in the Angolan free-tailed bat, Mops condylurus (Microchiroptera: Molossidae), in a subtropical environment, Mpumulanga, South Africa
Item type: Journal Article • Journal: African Zoology • Authors: L. Vivier --- Zoology Department, South Africa M. van der Merwe --- Department of Zoology and Entomology, South AfricaThe incidence of torpor during summer and winter in response to cold exposure in Mops condylurus was studied in a subtropical environment. Body temperature changes under natural roosting conditions during winter and summer were monitored using bats fitted with temperature-sensitive... -
Basking behaviour in the rock hyrax (Procavia capensis) during winter
Item type: Journal Article • Journal: African Zoology • Authors: Kelly J. Brown --- School of Biological and Conservation Sciences, University of KwaZulu-Natal, South Africa Colleen T. Downs --- School of Biological and Conservation Sciences, University of KwaZulu-Natal, South AfricaBasking is a behaviour frequently observed in the rock hyrax (Procavia capensis) during winter that supposedly plays a significant role in rewarming from nocturnal hypothermia. This behaviour, together with changes in body temperature and changes in black bulb temperatures (Tbb)... -
Effects of temperature and salinity on resting metabolism in two South African rock pool fish: the resident gobiid Caffrogobius caffer and the transient sparid Diplodus sargus capensis
Item type: Journal Article • Journal: African Zoology • Authors: J. O. G. Kemp [AN0001]Intertidal rock pools are inherently dynamic environments that experience marked changes in physico-chemical parameters over diel, tidal and seasonal time scales. Fish that inhabit the intertidal zone can generally be characterized as either permanent residents or transients/visitors. This study investigates... -
Aardvark burrows: a potential resource for animals in arid and semi-arid environments
Item type: Journal Article • Journal: African Zoology • Authors: G.M. Whittington-Jones --- Wildlife and Reserve Management Research Group, Department of Zoology and Entomology, South Africa R.T.F. Bernard --- Wildlife and Reserve Management Research Group, Department of Zoology and Entomology, South Africa D.M. Parker --- Wildlife and Reserve Management Research Group, Department of Zoology and Entomology, South AfricaArid and semi-arid environments are characterized by extreme fluctuations in temperature and low rainfall, which present significant challenges to the animals inhabiting these areas. However, the presence of burrows may allow animals to avoid climatic extremes and predators and may... -
Environmental conditions during mass mortalities of the ascidian Pyura stolonifera (Heller) in the Tsitsikamma Marine Protected area
Item type: Journal Article • Journal: African Zoology • Authors: Nicholas Hanekom --- South African National Parks, South AfricaMass mortalities of the ascidian Pyura stolonifera occurred along the Tsitsikamma coast in May 1991 and again in February 2012, following infection of large proportions of the population with a white microbial growth. P. stolonifera appeared to be the only... -
No effects of huddling on core body temperature in rock hyrax, Procavia capensis
Item type: Journal Article • Journal: African Zoology • Authors: C. T. Downs --- University of KwaZulu-Natal, South Africa K. Wimberger --- University of KwaZulu-Natal, South Africa A. L. Wilson --- University of KwaZulu-Natal, South AfricaHuddling is a behavioural energy conservation mechanism that is widely used by many small endotherms at low ambient temperatures. Huddling has many benefits, including decreasing the metabolic cost of maintaining body temperature (Tb), reducing the amount of heat lost to... -
Roost temperature and fidelity of Wahlberg’s epauletted fruit bat, Epomophorus wahlbergi, in an urban environment
Item type: Journal Article • Journal: African Zoology • Authors: Dominic P. Rollinson --- School of Life Sciences, University of KwaZulu-Natal, South Africa Joy C. Coleman --- School of Life Sciences, University of KwaZulu-Natal, South Africa Colleen T. Downs --- School of Life Sciences, University of KwaZulu-Natal, South AfricaGenerally,Wahlberg’s epauletted fruit bat (Epomophorus wahlbergi) roost in trees or under the eaves of buildings. This study investigated the roosting dynamics of E. wahlbergi in the urban environment of Pietermaritzburg, South Africa. To determine roost fidelity bats were radiotracked to... -
Food abundance explains the breeding season of a tropical shorebird, the Crab Plover Dromas ardeola
Item type: Journal Article • Journal: Ostrich: Journal of African Ornithology • Authors: Giuseppe De Marchi --- Dipartimento di Scienze della Terra e dell'Ambiente, Italy Giorgio Chiozzi --- Museo Civico di Storia Naturale, Italy Dawit Semere --- Research Division, Eritrea Yohannes Mebrahtu --- Research Division, Eritrea Farhad Hosseini Tayefeh --- Department of the Environment Provincial Office, Iran Mohammed Almalki --- Department of Biology, College of Science, Kingdom of Saudi Arabia Mauro Fasola --- Dipartimento di Scienze della Terra e dell'Ambiente, ItalyThe timing of breeding in birds is a life-history trait that generally depends on food availability, but other factors may play a role, particularly in tropical areas where food availability is less seasonal than in temperate or polar areas. We... -
The impact of high temperatures on foraging behaviour and body condition in the Western Australian Magpie Cracticus tibicen dorsalis
Item type: Journal Article • Journal: Ostrich: Journal of African Ornithology • Authors: Emily K Edwards --- School of Animal Biology, Australia Nicola J Mitchell --- School of Animal Biology, Australia Amanda R Ridley --- Centre for Evolutionary Biology, School of Animal Biology, AustraliaHigh temperatures can pose significant thermoregulation challenges for endotherms, and determining how individual species respond to high temperatures will be important for predicting the impact of global warming on wild populations. Animals can adjust their behaviour or physiology to cope... -
Spatio-temporal variability of five surface water quality parameters in the Swartvlei estuarine lake system, South Africa
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: IA Russell --- South African National Parks, South AfricaVariability of salinity, temperature, pH, dissolved oxygen and turbidity in the temporarily open/closed Swartvlei estuarine system, measured from 1991 to 2013, was investigated at various temporal (seasonal, estuarine open/closed phase, long-term) and spatial (inter- and intra-waterbody) scales. Longitudinal pH and... -
Influence of climate variables on Cyperus papyrus stomatal conductance in Lubigi wetland, Kampala, Uganda
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: A Opio --- Department of Biology, Uganda MB Jones --- Department of Botany, Ireland F Kansiime --- Department of Environmental Management, Uganda T Otiti --- Department of Physics, UgandaCyperus papyrus forms highly productive wetlands in tropical Africa, but the environmental control of transpirational water loss in wetlands is poorly understood. The influence of climate variables on papyrus stomatal conductance in dry and wet seasons of the year was... -
Effect of heat stress on seed yield components and oil composition in high- and mid-oleic sunflower hybrids
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: Rouxléne van der Merwe --- Department of Plant Sciences, South Africa Maryke T Labuschagne --- Department of Plant Sciences, South Africa Liezel Herselman --- Department of Plant Sciences, South Africa Arno Hugo --- Department of Microbial, Biochemical and Food Biotechnology, South AfricaHigh temperature stress is a major environmental factor influencing processes such as growth, yield and quality of crops. The objective of this study was to assess the effect of heat stress, applied during grain-filling, on seed yield- and oil quality... -
Movement behaviour of largemouth bass Micropterus salmoides in a South African impoundment
Item type: Journal Article • Journal: African Zoology • Authors: Dylan H Howell --- Department of Ichthyology and Fisheries Science, South Africa Paul D Cowley --- Department of Ichthyology and Fisheries Science, South Africa Amber-Robyn Childs --- Department of Ichthyology and Fisheries Science, South Africa Olaf LF Weyl --- Department of Ichthyology and Fisheries Science, South AfricaThe objectives of this study were to describe movements and area use patterns of largemouth bass Micropterus salmoides in relation to abiotic factors (water temperature, river inflow and water level). The study was conducted in the Kubusi arm of Wriggleswade... -
Growth and longevity of Exosphaeroma hylocoetes (Isopoda) under varying conditions of salinity and temperature
Item type: Journal Article • Journal: African Zoology • Authors: T.O. Henninger --- Department of Zoology and Entomology, South Africa P.W. Froneman --- Department of Zoology and Entomology, South Africa A.J. Booth --- Department of Ichthyology and Fisheries Science, South Africa A.N. Hodgson --- Department of Zoology and Entomology, South AfricaThe effect of temperature (15 and 25°C) and salinity (15 and 35 practical salinity units) combinations on the growth and longevity of the South African estuarine isopod Exosphaeroma hylocoetes was investigated and data analysed using the logistic growth model. No... -
Seasonal variations in the operating temperature of silicon solar panels in southern Ghana
Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: H.A. Koffi --- Department of Physics, Ghana V.C.K. Kakane --- Department of Physics, Ghana A. Kuditcher --- Department of Physics, Ghana A.F. Hughes --- Department of Physics, Ghana M.B. Adeleye --- Department of Physics, Ghana J.K.A Amuzu --- Department of Physics, GhanaThis work deals with the seasonal daily variation of the operating temperature of silicon solar panels under tropical atmospheric conditions, including high turbidity (Harmattan dust particles). Data was collected from March 2010 to July 2012 at Legon (0°11′08″ W, 5°39'04″... -
Effect of briquetting temperature on the properties of biomass briquettes
Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: Okey Francis Obi --- Agricultural and Bioresources Engineering Department, Faculty of Engineering, NigeriaThe importance of and growing worldwide interest in developing technologies that could utilise biomass material cannot be over looked particularly in developing countries. This study investigated the effect of briquetting temperature (normal and high temperature) on the physical and combustion... -
Differential dependence of apple (Malus domestica Borkh.) cultivars on the xanthophyll cycle for photoprotection
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: Simeon Hengari --- WRaDAC, Namibia Karen I Theron --- Department of Horticultural Science, South Africa Stephanie JE Midgley --- 84 Arum Road, South Africa Willem J Steyn --- Department of Horticultural Science, South AfricaThe dependence of fruit peel photosystems of ‘Granny Smith’, ‘Braeburn’, ‘Fuji’, ‘Golden Delicious’ and ‘Topred’ apple (Malus domestica Borkh.) peel on the xanthophyll cycle for photoprotection was studied under laboratory conditions. Mature fruit peel was either treated with 1 mm dithiothreitol... -
Influence of the annual flood-pulse on catch per unit effort, condition and reproduction of Clarias gariepinus from the upper Okavango Delta, Botswana
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: T Bokhutlo --- Department of Biology and Biotechnological Sciences, Botswana OLF Weyl --- South African Institute for Aquatic Biodiversity, South Africa K Mosepele --- Okavango Research Institute (University of Botswana), Botswana GG Wilson --- Ecosystem Management, School of Environmental and Rural Science, AustraliaCatch per unit effort (CPUE), length, weight and maturity data for Clarias gariepinus were collected during monthly gillnet surveys in the upper Okavango Delta between 2001 and 2009 to investigate their relationship with the annual flood-pulse. CPUE, condition factor (K)... -
Monitoring eucalypt bud temperature using mobile temperature loggers
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: Robin AW Gardner --- Institute for Commercial Forestry Research, South Africa Michael J Savage --- Agrometeorology Discipline, School of Agricultural, Earth and Environmental Sciences, South Africa Isa Bertling --- Horticultural Science Discipline, School of Agricultural, Earth and Environmental Sciences, South AfricaWinter chilling is a key environmental trigger of floral induction in temperate Eucalyptus. Over the past two decades, considerable site × eucalypt flowering interaction research has been undertaken over a range of high elevation (>1 100 m asl) forestry sites in... -
Summer and winter differences in zooplankton biomass, distribution and size composition in the KwaZulu-Natal Bight, South Africa
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: M Pretorius --- University of the Western Cape, South Africa JA Huggett --- Branch: Oceans and Coasts, Department of Environmental Affairs, South Africa MJ Gibbons --- University of the Western Cape, South AfricaZooplankton biomass and distribution in the KwaZulu-Natal Bight were investigated in relation to environmental parameters during summer (January–February 2010) and winter (July–August 2010). Mean zooplankton biomass was significantly higher in winter (17.1 mg dry weight [DW] m–3) than in summer... -
Observations and mechanisms of upwelling in the northern KwaZulu-Natal Bight, South Africa
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: MJ Roberts --- Ocean Sciences and Marine Food Security, South Africa C Nieuwenhuys --- Bayworld Centre for Research and Education, South AfricaNew in situ time-series data were acquired by two ADCP moorings placed on the shelf off Richards Bay on the east coast of South Africa at depths of 25 m and 582 m between October 2009 and August 2010. The... -
Modelling the tides and their impacts on the vertical stratification over the Sofala Bank, Mozambique
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: CM Chevane --- Instituto Nacional de Hidrografia e Navegação, Mozambique P Penven --- LMI ICEMASA, Laboratoire de Physique des Océans, France FPJ Nehama --- Escola Superior de Ciências Marinhas e Costeiras, Mozambique CJC Reason --- Department of Oceanography, South AfricaThe Sofala Bank, a wide shelf located along the central coast of Mozambique, hosts tides with high amplitudes. The Regional Ocean Modelling System (ROMS) was used to analyse the tidal currents on the bank and to investigate their effects on... -
Influence of temperature, aluminium chloride toxicity and exposure to Bacillus subtilis on the germination of okra
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: Matsobane T Mathiba --- Department of Agriculture and Animal Health, South Africa Khayalethu Ntushelo --- Department of Agriculture and Animal Health, South Africa Fhatuwani Mudau --- Department of Agriculture and Animal Health, South AfricaInfluences of heat, aluminium chloride concentration and exposure to Bacillus subtilis on germination of okra seed were investigated. A factorial experiment was conducted using Petri dish assays, and seed germination percentage and coleoptile length were recorded for the different treatments... -
Vegetative growth of Amaranthus hybridus and Amaranthus tricolor under different watering regimes in different seasons in southern Mozambique
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: Jerónimo EMM Ribeiro --- Department of Agronomy, South Africa Petrus J Pieterse --- Department of Agronomy, South Africa Sebastião I Famba --- Faculty of Agronomy and Forestry Engineering, MozambiqueDrought-tolerant crops with high nutritional value such as amaranth leafy vegetables have the potential to improve the diet of rural communities in dry semi-arid areas of southern Mozambique. A study was conducted aiming to assess the vegetative growth and leaf... -
Historical vegetation–environment patterns for assessing the impact of climatic change in the mountains of Lesotho
Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: Craig Morris --- Agricultural Research Council – Livestock Business Division, c/o School of Life Sciences, South AfricaClimate change will probably profoundly impact the Maloti Mountains in Lesotho, which are likely to have a warmer, wetter and more CO2-enriched (eCO2) atmosphere in the future. Intensive smallstock grazing could exacerbate the effects of climate change on the mountain... -
Comparison of infrared thermography and miniature Deltatron accelerometer sensors in the measurement of structural vibration characteristics
Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: Stephen M. Talai --- Department of Mechanical Engineering, South Africa Dawood A. Desai --- Department of Mechanical Engineering, South Africa P. Stephan Heyns --- Department of Mechanical and Aeronautical Engineering, South AfricaThis paper investigates the comparison of infrared thermography (IRT) and miniature Deltatron accelerometer sensors in measuring structural vibration characteristics in terms of frequency and displacement, given that of age IRT has fully grown for temperature condition monitoring. In addition, IRT... -
Environmental factors influencing the distribution and prevalence of Schistosoma haematobium in school attenders of ILembe and uThungulu Health Districts, KwaZulu-Natal Province, South Africa
Item type: Journal Article • Journal: Southern African Journal of Infectious Diseases • Authors: Nkosinathi Banhela --- Discipline of Public Health Medicine, South Africa Myra Taylor --- Discipline of Public Health Medicine, South Africa Siphosenkosi Gift Zulu --- Discipline of Public Health Medicine, South Africa Linnea Sund Strabo --- Norwegian Centre for Imported and Tropical Diseases, Department of Infectious Diseases Ullevaal, Norway Eyrun Floerecke Kjetland --- Discipline of Public Health Medicine, South Africa Svein Gunnar Gundersen --- Research Department, NorwaySchistosoma haematobium infection is reported to facilitate the development of urogenital diseases. Its symptoms include haematuria, dysuria and tiredness, and it may cause cognitive decline in children. The prevalence of S. haematobium infection needs to be known in endemic areas... -
Validation and downscaling of Advanced Scatterometer (ASCAT) soil moisture using ground measurements in the Western Cape, South Africa
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: Jason Moller --- Institute for Water Studies, South Africa Nebo Jovanovic --- Institute for Water Studies, South Africa Cesar L Garcia --- Consejo Nacional de Investigaciones Cientificas y Tecnologicas (CONICET – UCC), Argentina Richard DH Bugan --- CSIR, South Africa Dominic Mazvimavi --- Institute for Water Studies, South AfricaSatellite-based remote sensing of soil water content (SWC) is a promising technology for hydrological applications to overcome large spatiotemporal variabilities of SWC. This study investigated the performance of the Advanced Scatterometer (ASCAT) soil moisture product on METOP satellite (∼12.5 km... -
Evaluation of satellite retrievals of water quality parameters for Lake Victoria in East Africa
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: A Gidudu --- Department of Geomatics and Land Management, Uganda R Mugo --- Regional Centre for Mapping Resource for Development, Nairobi Kenya L Letaru --- Department of Geomatics and Land Management, Uganda J Wanjohi --- Regional Centre for Mapping Resource for Development, Nairobi Kenya R Nakibule --- Department of Geomatics and Land Management, Uganda E Adams --- Earth System Science Centre–University of Alabama in Huntsville, USA A Flores --- Earth System Science Centre–University of Alabama in Huntsville, USA B Page --- Earth System Science Centre–University of Alabama in Huntsville, USA W Okello --- National Fisheries Resources Research Institute, UgandaLake Victoria in East Africa is a major ecosystem, whose size and importance has warranted the exploration of MODIS imagery to provide continuous and accurate water quality information. To this effect, two sea expeditions (in November 2014 and February 2015)... -
Relationships of water temperature and aquatic macroinvertebrate community structure with non-native riparian plant densities in the southern Cape, South Africa
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: NA Rivers-Moore --- Centre for Water Resources Research, South Africa HF Dallas --- Freshwater Research Centre, South Africa, and Nelson Mandela Metropolitan University, South Africa FC de Moor --- Albany Museum and Department of Zoology and Entomology, South Africa J Barendse --- Sustainability Research Unit/South African National Parks, South AfricaNon-native vegetation in the riparian zone impacts on water temperatures, flow patterns, degree of shading, channel modification, and changes to natural sediment loads. Freshwater ecosystems in the Garden Route Initiative planning domain are of particular conservation value, because of the... -
Environmental responses of jellyfish polyps as drivers of medusa populations off the coast of Namibia
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: L Ziegler --- Department of Biodiversity and Conservation Biology, South Africa MJ Gibbons --- Department of Biodiversity and Conservation Biology, South AfricaJellyfish populations in the southeastern Atlantic off the coast of Namibia have increased subsequent to the decline of small pelagic fisheries at the end of the 1960s, although the environment there has also become warmer and the waters off Walvis... -
Effects of climate change on malaria morbidity and mortality in Taraba State, Nigeria
Item type: Journal Article • Journal: African Zoology • Authors: J Jonathan --- Department of Zoology and Environmental Biology, Nigeria N Ivoke --- Department of Zoology and Environmental Biology, Nigeria IO Aguzie --- Department of Zoology and Environmental Biology, Nigeria CD Nwani --- Department of Zoology and Environmental Biology, NigeriaThe study investigated the effects of climatic changes on malaria parasite prevalence, morbidity and mortality in Taraba State, Nigeria. Using a retrospective study design, the study relied on secondary data covering a period from 2005 to 2014, obtained from Meteorological... -
The presence of artificial water points structures an arid-zone avian community over small spatial scales
Item type: Journal Article • Journal: Ostrich: Journal of African Ornithology • Authors: Salamatu Abdu --- FitzPatrick Institute of African Ornithology, DST-NRF Centre of Excellence, South Africa Alan TK Lee --- FitzPatrick Institute of African Ornithology, DST-NRF Centre of Excellence, South Africa Susan J Cunningham --- FitzPatrick Institute of African Ornithology, DST-NRF Centre of Excellence, South AfricaWater plays a key role in avian thermoregulation, especially when environmental temperatures approach or exceed body temperature. Birds living in arid environments need to either be adapted to life with unreliable access to water, or engage in large-scale movements to... -
Localised intermittent upwelling intensity has increased along South Africa’s south coast due to El Niño–Southern Oscillation phase state
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: MI Duncan --- Department of Ichthyology and Fisheries Science, South Africa NC James --- South African Institute for Aquatic Biodiversity (SAIAB), South Africa AE Bates --- Department of Ocean Sciences, Canada WS Goschen --- Institute for Coastal and Marine Research, Ocean Sciences Campus, South Africa WM Potts --- Department of Ichthyology and Fisheries Science, South AfricaThe El Niño–Southern Oscillation (ENSO) phase state is reported to drive interannual variability in sea temperatures along South Africa’s south coast through its influence on wind-induced upwelling processes. Whether ENSO drives the intensity of localised, abrupt, intermittent upwelling is less... -
Interactive effect of planting date and fertiliser application on maize growth and yield under dryland conditions
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: Dolapo B Akinnuoye-Adelabu --- Crop Science, School of Agricultural, Earth and Environmental Sciences, South Africa Tafadzwanashe Mabhaudhi --- Crop Science, School of Agricultural, Earth and Environmental Sciences, South Africa Albert T Modi --- Crop Science, School of Agricultural, Earth and Environmental Sciences, South AfricaUnderstanding the relationships among management practices during planting period will help producers to improve crop production under climate change. The interaction of planting date and soil fertility on maize yield was evaluated. Field trials were conducted during summer in 2014/15... -
Recent droughts in the Kruger National Park as reflected in the extreme climate index
Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: Johan Malherbe --- , South Africa Izak PJ Smit --- , South Africa Konrad J Wessels --- , United States Philip J Beukes --- , South AfricaAssociated with the 2015/2016 El Niño, extreme drought occurred over the Lowveld of South Africa. The area includes the Kruger National Park (KNP). Significant die-offs of a mega herbivore species occurred, corroborated by census data in KNP. The drought situation... -
Spatio-temporal distribution of organochlorine pesticide residues in water and sediments of tropical reservoirs: a case study of Bui Reservoir, Ghana
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: SB Jidauna --- , Ghana R Edziyie --- , Ghana BB Campion --- , GhanaThis study investigated the spatio-temporal distribution of organochlorine pesticides (OCPs) in water and sediments of the Bui Reservoir from June 2017 to May 2018, to provide baseline data for monitoring contamination in the Reservoir. Samples were collected during four seasons... -
Inter-annual growth response of three Miombo tree species to climatic effects
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: Francis Munalula --- , South Africa Thomas Seifert --- , South Africa Martina Meincken --- , South AfricaMiombo woodlands cover a large part of Southern Africa and contribute an important wood source for the local wood industry. The already observed and further predicted changes in climatic patterns can be expected to affect the wood properties of Miombo... -
Effects of nest management methods on hatching success and predation rates of hawksbill turtles on Cousine Island, Seychelles
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: J Gane --- , South Africa CT Downs --- , South Africa I Olivier --- , South Africa M Brown --- , South AfricaSea turtle populations have declined globally and are of conservation concern. We investigated the effects of nest management methods on hatching success and egg/hatchling predation rates of hawksbill turtles Eretmochelys imbricata on Cousine Island, Seychelles. We determined the effectiveness of... -
Evaluation of temperature effects on grade 20 concrete using response surface methodology
Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: Richie I. Umasabor --- , NigeriaThis paper examined the evaluation of temperature effects on grade 20 concrete using response surface methodology. An experimental research design was adopted, which produced fifty-one (51) concrete specimens. The specimens were cured and tested at 7, 18, and 28 days,... -
Seasonal variance in water quality, trace metals and infection variables of Cichlidogyrus philander Douëllou, 1993 (Monogenea, Ancyrocephalidae) infecting the gills of Pseudocrenilabrus philander (Weber, 1897) in the Padda Dam, South Africa
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: Patience C Igeh --- , South Africa Beric M Gilbert --- , South Africa Annemariè Avenant-Oldewage --- , South AfricaIncreasing awareness of deteriorating health of aquatic ecosystems, as a result of human activities, has led to the suggestion that fish host-parasite relationships are possible bioindicators of environmental pollution. This study examined the impact of water quality and trace elements... -
Potential impact of marine heatwaves on selected phytoplankton adapted to the Gulf of Guinea during stable hydrographic periods
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: E Acheampong --- , Ghana P Mantey --- , Ghana A Weremfo --- , GhanaReports suggest that the Gulf of Guinea (northeastern tropical Atlantic) frequently experiences marine heatwaves (MHW)—prolonged periods of anomalously warm seawater—of ≥1.5 °C above baseline. We assessed the likely impact of this anomaly on two microalgae, Thalassiosira weissflogii (diatom) and Gymnodinium... -
Earthworm diversity and density as affected by soil and climatic factors in Raymond Mhlaba municipality, Eastern Cape province, South Africa
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: Sixolise Mcinga --- , South Africa Alen Manyevere --- , South Africa P Mnkeni --- , TanzaniaEarthworms play a key role in improving soil health, and their diversity and density are mainly affected by soil and climatic factors. This study determined the effects of rainfall, temperature and selected soil properties on the diversity and density of... -
Are there long-term temporal trends of size composition and the length– weight relationship? Results for chokka squid Loligo reynaudii during the peak spawning season off the south coast of South Africa
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: MR Lipiński --- , South Africa MA Mmethi --- , South Africa D Yemane --- , South Africa J Githaiga-Mwicigi --- , South Africa WHH Sauer --- , South AfricaTemporal trends in the size composition (length frequency) and length–weight (L–W) relationship of chokka squid Loligo reynaudii on the south coast of South Africa were assessed over periods spanning 22 years: length frequencies from 1996 to 2017 (with 15 years... -
When cooling is worse than warming: investigations into the thermal tolerance of an endemic reef fish, Boopsoidea inornata
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: C Allison --- , South Africa C Muller --- , South Africa A-R Childs --- , South Africa W Froneman --- , South Africa LA Bailey --- , South Africa WM Potts --- , South AfricaRecent investigations suggest that global warming is likely to alter temperature regimes along the southeastern coastline of South Africa through the increased frequency of upwelling events. Identifying thermal thresholds is fundamental in predicting the response of marine ectotherms to rapidly... -
Diel activity patterns of two syntopic range-restricted geckos suggest idiosyncratic responses to climate change
Item type: Journal Article • Journal: African Zoology • Authors: MA Petford --- , South Africa GJ Alexander --- , South AfricaMeasures of activity patterns in relation to environmental conditions provide insights into ecologically driven requirements and climate preferences of species, particularly for ectotherms, due to the strong relationship between body temperature (Tb) and environmental temperatures. Lygodactylus incognitus (cryptic dwarf gecko)... -
Seasonal variation and drivers of zooplankton, macroinvertebrate and littoral fish communities from irrigation ponds in a semi-arid region in the Eastern Cape (South Africa)
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: L Mofu --- , South Africa T Dalu --- , South Africa RJ Wasserman --- , South Africa DJ Woodford --- , South Africa D Khosa --- , South Africa OLF Weyl --- , South AfricaIrrigation ponds are increasingly abundant globally, particularly in water-stressed countries with limited natural surface waters, yet knowledge of their ecology is limited. Here, we assessed zooplankton, macroinvertebrate, and littoral fish communities from irrigation ponds located in the Sundays River Valley... -
Climate smart technology for storage of fresh pro-vitamin A bio-fortified cassava
Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: Olumuyiwa Adekanmi Babarinsa --- , Nigeria Isaac Babatunde Oluwalana --- , Nigeria Mathew Kolawole Bolade --- , NigeriaClimate change is a problem affecting food security across the globe. The climate change effect of rising temperatures can be mitigated by using climate-smart crops such as cassava and climate-smart technology such as an Evaporative Cooling Structure (ECS). A 150 kg... -
Low constant temperature drying can be a satisfactory method to determinethe moisture content of impermeable seed coated species
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: Ganesh K Jaganathan --- University of Shanghai for Science and Technology, China Jiajin Li --- University of Shanghai for Science and Technology, China Baolin Liu --- University of Shanghai for Science and Technology, ChinaThe International Seed Testing Association (ISTA) recommends two methods for seed moisture content determination: high constant temperature drying, carried out at 130 °C for 1, 2, 3 or 4 hours, and low constant temperature drying, carried out at 103 °C... -
Assessment of the acoustic change in heat-treated Pinus elliottii and Bertholletia excelsa wood from homogeneous plantations in Brazil
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: Daiana Sousa de Jesus --- Federal Rural University of Rio de Janeiro, Brazil Jonnys Paz Castro --- Federal Rural University of Rio de Janeiro, Brazil Taiane Guedes --- Universidade Federal de Lavras, Brazil José Reinaldo Moreira da Silva --- Universidade Federal de Lavras, Brazil João Vicente de Figueiredo Latorraca --- Federal Rural University of Rio de Janeiro, Brazil Alexandre Miguel do Nascimento --- Federal Rural University of Rio de Janeiro, BrazilHeat treatment has been used in wood to improve its technological properties, but due to the complex nature of wood, it is necessary to carry out analyses to confirm the changes, and also to investigate which temperatures and protocols are... -
Diel activity patterns in a captive colony of rinkhals, Hemachatus haemachatus
Item type: Journal Article • Journal: African Journal of Herpetology • Authors: GrahamJ. Alexander --- University of the Witwatersrand, South Africa CatherineL. Marshall --- University of the Witwatersrand, South Africa -
How to make measurements in thermoregulatory studies: the heating debate continues
Item type: Journal Article • Journal: African Journal of Herpetology • Authors: Shelley Currin --- University of the Witwatersrand, South Africa Graham John Alexander --- University of the Witwatersrand, South Africa -
Temperature regulation in free-ranging ectotherms: what are the appropriate questions?
Item type: Journal Article • Journal: African Journal of Herpetology • Authors: PaulE. Hertz --- Barnard College, Columbia University, USA RaymondB. Huey --- University of Washington, USA RobertD. Stevenson --- University of Massachusetts Boston, USA -
A respone to Hertz, Huey and Stevenson
Item type: Journal Article • Journal: African Journal of Herpetology • Authors: Graham John Alexander --- University of the Witwatersrand, South Africa Shelley Currin --- University of the Witwatersrand, South Africa -
Wind- and eddy-driven upwelling over submarine canyons inshore of the northern Agulhas Current
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: G Rautenbach --- Nelson Mandela University, South Africa J Hermes --- , South Africa I Halo --- , South Africa T Morris --- , South Africa J Veitch --- , South AfricaThe iSimangaliso Wetland Park, located along the coastline of northern KwaZulu-Natal, hosts South Africa’s only subtropical coral reef system. Episodic upwelling events are observed inshore and at the heads of Diepgat, Leadsman and Leven canyons within the iSimangaliso Wetland Park... -
Long-term study of the drought impact on the phytoplankton concentration and assemblages in two water supply reservoirs in Namibia
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: Johannes Sirunda --- Namibia Water Corporation, Namibia Paul Oberholster --- University of the Free State, South Africa Gideon Wolfaardt --- Stellenbosch University, South Africa Christoff Truter --- Toronto Metropolitan University, Canada Sean van der Merwe --- University of the Free State, South AfricaRising temperatures and increased occurrences of droughts, brought on by climate change, are expected to affect reservoir water levels. We hypothesised that the decrease in reservoir volumes in dams with desert climates will favour the growth of phytoplankton biomass, measured... -
Effect of temperature on embryonic development and offspring performance of the African river prawn, Macrobrachium vollenhovenii
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: Judith G Makombu --- University of Buea, Cameroon Cynthia A Bih --- University of Buea, Cameroon Geneva O Nkongho --- Institute of Agricultural Research for Development (IRAD), Cameroon Pius M Oben --- University of Buea, Cameroon Rollins N Ndi --- University of Buea, Cameroon Clovis N Chombe --- University of Buea, Cameroon Mercy B Verkijika --- University of Buea, Cameroon Gerry K Sonkeng --- Aquaculture Tropicale (Aqua-Tropic), Cameroon Tekou Guegang --- University of Dschang, Cameroon Janet H Brown --- Institute of Aquaculture, University of Stirling, United KingdomMacrobrachium vollenhovenii (Herklots, 1857), the largest of the indigenous West African Palaemonidae prawns, has a high potential for aquaculture. This work was carried out to assess the effect of temperature on embryonic development and offspring quality of this species. In... -
Patterns in sightings of ocean sunfishes (Molidae) in the greater Dyer Island ecosystem, Western Cape, South Africa
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: RGA Watson --- , South Africa E Frey --- Queen’s University, Canada S Hörbst --- , South AfricaThis study aims to describe the distribution of ocean sunfishes (family Molidae) in the greater Dyer Island ecosystem off the southwest coast of South Africa. Between 2014 and 2022, local whale watching vessels operating under Dyer Island Cruises conducted 3... -
Marine macroalgae of the Agulhas Marine Province of South Africa: biodiversity, exploitation and potential for aquaculture
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: JJ Bolton --- University of Cape Town, South Africa CD McQuaid --- Rhodes University, South AfricaThe Agulhas Marine Province (AMP) extends along most of the south coast of South Africa, from Cape Agulhas to the vicinity of the Mbashe River mouth in the Eastern Cape Province, and has its own distinctive warm-temperate seaweed flora, with... -
Water quality monitoring and measuring physicochemical parameters using wireless sensor networks
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: N Satyanarayana Murthy --- , India SF Ahamed --- , IndiaIn a world grappling with the dire consequences of poor sanitation and inadequate water conditions, there is an urgent need for a comprehensive solution. The staggering statistics of over 400 million affected cases and 15–25 million lives lost worldwide underscore... -
Variations in the heart rate of Mediterranean mussels Mytilus galloprovincialis and brown mussels Perna perna under thermal stress on rocky shores of South Africa
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: K Beine --- University of Johannesburg, South Africa LJ Connell --- University of Johannesburg, South Africa R Greenfield --- University of Johannesburg, South AfricaIntertidal mussels experience prolonged emersion during low tide, followed by rapid submergence cooling during high tide, causing temperature-induced stress responses. This study examined variations in heart rate to investigate the relationship between emerged and submerged thermal stress in Mediterranean mussels... -
Orientation, thermal characteristics and structural dimensions of Mangrove Kingfisher Halcyon senegaloides nest cavities in arboreal termitaria in central Mozambique
Item type: Journal Article • Journal: Ostrich: Journal of African Ornithology • Authors: Darren W Pietersen --- University of Pretoria, South Africa Gregory BP Davies --- , United States of America Craig T Symes --- University of the Witwatersrand, South AfricaThe breeding ecology of the Mangrove Kingfisher Halcyon senegaloides (family Alcedinidae) remains poorly known. While the few nests recorded in southern and East Africa have been in tree hollows, a seasonal population in central Mozambique woodland breeds in cavities in... -
Behavioural responses to air temperature change in helmeted guineafowl Numida meleagris
Item type: Journal Article • Journal: African Zoology • Authors: Johann H van Niekerk --- University of South Africa, South Africa Marta Rodríguez-Rey --- Universidad de Alcalá, Forest Ecology and Restoration Research Group (FORECO), Spain Fabián Casas --- Universidad de Granada, Spain Giovanni Forcina --- Global Change Ecology and Evolution Research Group (GloCEE)/Soil Biology and Subterranean Ecosystems Research Group (GIBSES), SpainDeciphering the behavioural responses of helmeted guineafowl Numida meleagris (Linnaeus, 1758) to temperature variation is key to understanding its eco-ethology and implementing sound management strategies. Here, we tested the ‘warmer together’ hypothesis, which states that thermoregulatory cost reduction (i.e. body... -
Assessing the thermal tolerance of a cosmopolitan eurythermal species, the flathead mullet Mugil cephalus
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: DL Mukhari --- Rhodes University, South Africa A-R Childs --- Rhodes University, South Africa BA Ziko --- Rhodes University, South Africa TS Murray --- Rhodes University, South AfricaWater temperature is a key abiotic factor affecting fish physiology, behaviour and distribution, with fluctuations impacting species assemblages and habitat use. The flathead mullet Mugil cephalus is a eurythermal species with a cosmopolitan distribution across tropical, subtropical and temperate coastal... -
Will I survive? Assessing the thermal tolerance of an estuary-dependent mugilid, Chelon dumerili, in a changing climate
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: BA Ziko --- South African Institute for Aquatic Biodiversity (SAIAB), South Africa AR Childs --- South African Institute for Aquatic Biodiversity (SAIAB), South Africa DL Mukhari --- South African Institute for Aquatic Biodiversity (SAIAB), South Africa TS Murray --- South African Institute for Aquatic Biodiversity (SAIAB), South AfricaDetermining the thermal tolerance limits of fishes is crucial for understanding their persistence in the face of anthropogenic climate change. This study used dynamic critical thermal assays to determine the upper (CTmax) and lower (CTmin) critical thermal limits of an...