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Micropropagation of Eucalyptus radiata ssp. radiata Using Explants from Mature and Coppice Material
Item type: Journal Article • Journal: South African Forestry Journal • Authors: S.H. Chang --- Department of Forestry, RSA D. G.M. Donald --- Department of Forestry, RSA G. Jacobs --- Department of Horticulture, RSANodes from young field-grown coppice regrowth and branches of a mature tree of Eucalyptus radiata ssp. radiata were cultured on a MS medium containing BA and NAA. BA at 0,5 mg/ℓ and NAA at 0,01-0,1 mg/ℓ were most effective in... -
Variation in important pasture grasses: I. Morphological and geographical variation
Item type: Journal Article • Journal: Journal of the Grassland Society of Southern Africa • Authors: G.E. Gibbs Russell --- Department of Agriculture and Water Supply, J.J. Spies --- Department of Agriculture and Water Supply,Seven species are important pasture grasses throughout the western Transvaal, Orange Free State, northern Cape and Natal. Taxonomically, each is a widely distributed species complex with a range of morphological variants and many ecotypes. The local forms well suited to... -
Variations in floristic and palatability composition, yield of veld and of soil characteristics on a paddock scale
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: D.L. Barnes --- Department of Agriculture and Water Supply (Transvaal Region), Republic of South Africa G.D. Kotzé --- Department of Agriculture and Water Supply (Transvaal Region), Republic of South Africa B.H. Beukes --- Department of Agriculture and Water Supply (Transvaal Region), Republic of South Africa C. Kohlmeyer --- Department of Agriculture and Water Supply (Transvaal Region), Republic of South AfricaFive parallel 900-m line-transects were laid out 100 m apart in relatively homogeneous veld. Floristic composition, yields of dry matter, soil forms and series, effective depth, clay content of the top and subsoil, and the pH of the topsoil were... -
Genotypic variation in leaf water potential of field-grown soybeans (Glycme max L. Merr.) and its association with dryland yield
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: R.F. Grant --- , Republic of South Africa J.D. Lea --- Department of Crop Science, Republic of South AfricaMaintenance of leaf water potential (ΨL) during periods of water stress may constitute an important drought-avoiding response. The identification of genotypic variation for this characteristic is, however, made difficult by the fact that comparative values for ΨL must be measured... -
Recognition of natural soil bodies using textural properties of red freely drained soil profiles from KwaZulu-Natal and Mpumalanga
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: D.P. Turner --- , South Africa M.C. Laker --- Department of Plant Production and Soil Science, South AfricaThe research examines the range of variation of soil texture for red freely drained soils associated with six of the major geological formations of KwaZulu-Natal and Mpumalanga. The soil profile information is derived from particle size analyses of over 4... -
The effects of spatial variation of certain soil properties on the winter yield of a lucerne stand
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: A. Venter --- Department of Plant Production and Soil Science, South Africa D.J. Beukes --- , South Africa A.S. Claassens --- Department of Plant Production and Soil Science, South Africa M. Van Meirvenne --- Department Soil Management and Soil Care, BelgiumIn general, agricultural fields are managed as uniform units, ignoring spatial soil heterogeneity and its effects on growth and yield of field crops. This study was conducted from June 2001—February 2002 and examines the effects of spatial variation of soil... -
Regional sustainability in table grape production on saline soils
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: W. P. de Clercq --- Department of Soil Science, South Africa M. Van Meirvenne --- Department of Soil Management and Soil Care, BelgiumA study was done in South Africa to investigate the state of the soil salt content and its effect on plant growth on a regional rather than a point basis. The study site went through a development phase since 1996... -
Variation of agronomic traits of potato somaclones produced by meristem culture
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: Viive Rosenberg --- Plant Biotechnological Research Centre EVIKA Saku, Estonia Marje Särekanno --- Plant Biotechnological Research Centre EVIKA Saku, Estonia Katrin Kotkas --- Plant Biotechnological Research Centre EVIKA Saku, Estonia Virge Vasar --- Plant Biotechnological Research Centre EVIKA Saku, Estonia Ann Ojarand --- Plant Biotechnological Research Centre EVIKA Saku, EstoniaFollowing a thermotherapy virus eradication procedure potato plantlets were multiplied as meristem clones in vitro. The agronomic traits of meristem clones were compared in field trials over three years. A total of 16 meristem clones of cultivar Agric dzeltenie and... -
Phosphorus enhances aluminium tolerance in both aluminium-tolerant and aluminium-sensitive wheat seedlings
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: MT Iqbal --- Department of Agronomy and Agricultural Extension, BangladeshSeedlings growing in acid soils suffer both phosphorus (P) deficiency and aluminium (Al) toxicity stresses. An experiment was conducted to study the effects of Al and P interaction on Al-tolerant (ET8) and Al-sensitive (ES8) wheat genotypes in an acid soil... -
Effect of pH on growth, mineral content and essential oil quality of buchu (Agathosma betulina) grown under controlled conditions
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: Babalwa Ntwana --- Department of Agronomy, South Africa G André Agenbag --- Department of Agronomy, South Africa Petrus Langenhoven --- , South AfricaBuchu (Agathosma betulina) is a traditional medicinal plant in the Western Cape province of South Africa and the essential oil derived from the leaves is exported in large volumes. The essential oil is not only used for medicinal purposes, but... -
The influence of site, season and day of the week on exploitation of rocky intertidal biota in central Transkei, South Africa
Item type: Journal Article • Journal: South African Journal of Marine Science • Authors: V. N. Majiza T. A. LasiakTemporal and spatial variations in the pattern and intensity of exploitative use of rocky shores in the densely populated central Transkei region of the south-east coast of South Africa are described. Surveys of intertidal exploiters and their catches were conducted... -
THE LIMNOLOGY OF SOME SOUTH AFRICAN IMPOUNDMENTS I. THE PHYSICO-CHEMICAL LIMNOLOGY OF HARTBEESPOORT DAM
Item type: Journal Article • Journal: Journal of the Limnological Society of Southern Africa • Authors: W.E. Scott --- , South Africa M.T. Seaman --- , South Africa A.D. Connell --- , South Africa S.I. Kohlmeyer --- , South Africa D.F. Toerien --- , South AfricaHartbeespoort Dam is a eutrophic, warm monomictic lake with overturn occurring in April. The lake is stratified for about six months of the year and in late summer the stratification appears stable. Light penetration in the dam depends both on... -
VIABLE HETEROTROPHIC BACTERIAL POPULATION STRUCTURE OF A TURBID MAN-MADE IMPOUNDMENT
Item type: Journal Article • Journal: Journal of the Limnological Society of Southern Africa • Authors: D.F. Toerien --- , Republic of South Africa D.N. Sadie --- , Republic of South Africa H. J.J. van Vuuren --- Department of Microbiology, Republic of South Africa R.P. Tracey --- Department of Microbiology, Republic of South AfricaSeventy one heterotrophic bacterial isolates were obtained from Wuras Dam, phenotypically characterized and clustered with the unweighted-pair group method. Three groups were obtained of which the first contained 59 members in several clusters. Overall this group was characterized by a... -
SOME ASPECTS OF THE DISTRIBUTION OF REACTIVE PHOSPHORUS IN LAKE McILWAINE, RHODESIA: PHOSPHORUS LOADING AND SEASONAL RESPONSES
Item type: Journal Article • Journal: Journal of the Limnological Society of Southern Africa • Authors: J.A. Thornton --- Hydrobiology Research Unit,Between November 1976 and September 1977, samples were taken on a fortnightly basis from a representative station in Lake McIlwaine. In addition an intensive study of the riverine input of reactive phosphorus was conducted. Samples were analysed for total reactive... -
NOTE ON THE OCCURRENCE OF A VENTRAL SUCKER-LIKE MOUTH FORM IN LABEO UMBRATUS (PISCES, CYPRINIDAE)
Item type: Journal Article • Journal: Journal of the Limnological Society of Southern Africa • Authors: I.G. Gaigher --- , South AfricaThe occurrence of a ventral sucker-like mouth form in certain populations of Labeo umbratus, which are free from competition by L. aapensis, is reported. It is proposed that this might be an adaptation to feeding off stones which enhances the... -
A QUARTER CENTURY OF GREAT LAKES RESEARCH IN AFRICA
Item type: Journal Article • Journal: Journal of the Limnological Society of Southern Africa • Authors: DavidH. Eccles --- , United KingdomThe African Great Lakes differ from shallower large African lakes by undergoing seasonal stratification and from large reservoirs in having long residence times, so that the ionic concentration of the lake water differs substantially from that of the inflows. -
A COMPARISON OF ALLOZYME HETEROZYGOSITY AND LIFE HISTORY VARIABLES IN FOUR STRAINS OF AFRICAN CATFISH (CLARIAS GARIEPINUS)
Item type: Journal Article • Journal: Southern African Journal of Aquatic Sciences • Authors: J. P. Grobler --- , , L. C. Hoffman --- , , South Africa J. F. Prinsloo --- , , South AfricaWe studied allozyme polymorphism and its relation to morphological characteristics in 122 individuals from four lines of African catfish. Starch gel electrophoresis was used to screen 26 loci, of which five were polymorphic. Average heterozygosity levels differed moderately among lines... -
A PRELIMINARY BIOCHEMICAL GENETIC STIJDY OF TWO POPULATIONS OF LITHOGNATHUS AURETI (PERCIFORMES: SPARIDAE)
Item type: Journal Article • Journal: Southern African Journal of Aquatic Sciences • Authors: F. H. van der Bank --- , , South Africa J. A. Holtzhausen --- , NamibiaTwo populations of Lithognathus aureti were electrophoretically analysed to determine the extent of genetic divergence between, and variation within them. Gene products of 35 protein coding loci showed no fixed allele differences between these populations. However, significant genotypic differentiation between... -
Preliminary results of a stocking rate trial in Lesotho
Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: LM Mpiti-Shakhane GY Kanyama-Phiri WO Odenya JW BandaForage responses to stocking rates and seasons were determined over a one-year period. The experimental design consisted of three stocking rates namely, light (2.0ha LSU-1), moderate (1.25ha LSU-1) and heavy (0.5ha LSU-1) and four seasons (autumn, winter, spring and summer)... -
Seasonal botanical and chemical composition of sheep and goat diets on a common range in eastern Africa
Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: RobinsonK Ngugi JosephN Ndung'u DicksonM Nyariki NashonKR MusimbaThe botanical and chemical composition, intake and digestibility of local sheep (Ovis aries) and goat (Capra hirtus) diets were evaluated over the wet (growing) and dry (dormant) seasons. Diet botanical composition was related to the vegetation composition on the range... -
Variation in Wood Density and Tracheid Length in Pinus patula grown in Zimbabwe
Item type: Journal Article • Journal: The Southern African Forestry Journal • Authors: A. Muneri --- Cooperative Research Centre for Temperate Hardwood Forestry, V. Balodis --- ,Within-tree variation of wood density was studied for 14-and 25-year-old Pinus patula Schiede & Deppe trees grown at two plantation sites in Zimbabwe. Three trees of each age per site were selected and disc samples obtained at six relative height... -
Variation Reduction and Lu Lu-smoothing
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: C.H. RohwerIn the space of absolutely summable sequences the total variation of a sequence becomes a natural norm, and is a measure of smoothness. This norm is preserved by the so-called LU LU-smoothers, in that the variation of the image plus... -
Fully Trend Preserving Operators
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: C.H. RohwerThe concept of fully trend preserving (ftp) operators on sequences was introduced to prove variation preservation on the outputs of LULU-separators. It turns out that this property is central in further analysis of compositions of LULU-smoothers, and other smoothers. Several... -
Extension of the Dirichlet-Jordan Convergence Criterion for Exponential Weights
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: H.P. MasheleThe well-known Dirichlet-Jordan Criterion for Fourier series states that the trigonometric Fourier series of a 2π periodic function f having bounded variation converges to ½[f(x + 0) + f(x – 0)] for every x and this convergence is uniform on... -
A positive note on a counterexample by Arens
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Gerard Buskes Robert PageIn his seminal paper [2], Arens gave an example of a positive bilinear map P : l 1 × l 1 → R that is not regular. In this note we show that for Banach lattices E such a bilinear... -
L p -valued Measures Without Finite X-semivariation for 2 < p < ∞
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Brian Jefferies Susumu Okada Luis Rodrígues-PiazzaWe show that for 1 ≤ p < ∞, the property that every L p -valued vector measure has finite X-semivariation in L p (μ, X) is equivalent to the property that every continuous linear map from l... -
Uniqueness and spectral variation in Banach algebras
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: G. Braatvedt --- Department of Mathematics, South Africa R. Brits --- Department of Mathematics, South AfricaLet A be a complex semisimple Banach algebra with identity. We explore the situation whereby a portion of the elements of A have the same spectrum under multiplication by a ∈ A, as under multiplication by b ∈ A; and... -
Beacons in the limnological landscape
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: BR AllansonAn overview is given of a number of major developments in the limnology of South Africa, Zimbabwe and Namibia. None was possible without the involvement of enthusiastic investigators who, over some 70 years, stimulated the growth of freshwater research in... -
Application of the Indicators of Hydrological Alteration method to the Mkomazi River, KwaZulu-Natal, South Africa
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: V Taylor --- , South Africa R Schulze --- , South Africa G Jewitt --- , South AfricaHydrological regimes play a major role in structuring the biotic diversity within river ecosystems and hydrological variation is recognised as a primary driving force within those ecosystems. The US Nature Conservancy developed a method known as the Indicators of Hydrological... -
Feeding dynamics of Palaemon peringueyi (Decapoda, Caridea) in the temporarily open/closed Kasouga Estuary, South Africa
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: PW Froneman --- Department of Zoology and Entomology, South Africa TO Henninger --- Department of Zoology and Entomology, South AfricaThe feeding ecology of the caridean shrimp Palaemon peringueyi in the temporarily open/closed Kasouga Estuary, Eastern Cape, was examined during summer and winter employing stomach fullness index (SFI) analysis. Mean SFI values for male and female shrimp during summer ranged... -
Distribution, abundance and diversity of macrozoobenthos in Aiba Reservoir, Iwo, Nigeria
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: OE Atobatele --- Department of Biological Sciences, Nigeria OA Ugwumba --- Department of Zoology, NigeriaSpatial and seasonal variation in macrozoobenthic composition, abundance and diversity in Aiba Reservoir were investigated bimonthy between June 2004 and April 2005 using a van Veen grab. A depauperate fauna of nine taxa was recorded. Generally, larger numbers of taxa... -
Body-size distribution, biomass estimates and life histories of common insect taxa associated with a submerged macrophyte Lagarosiphon ilicifolius in the Sanyati Basin, Lake Kariba, Zimbabwe
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: C Phiri --- , Zimbabwe A Chakona --- Department of Ichthyology and Fisheries Science, South Africa JA Day --- Freshwater Research Unit, Zoology Department, South AfricaThe body-size distributions and biomass estimates of Caenis (Ephemeroptera: Caenidae), Cloeon (Ephemeroptera: Baetidae), Coenagrionidae (Odonata), Micronecta (Hemiptera: Corixidae), Chironominae (Diptera: Chironomidae) and Orthocladiinae (Diptera: Chironomidae), the most common and abundant insect taxa associated with a submerged macrophyte Lagarosiphon ilicifolius in... -
A morphological study on species of African Mormyrus (Teleostei: Mormyridae) and their electric organ discharges
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: B Kramer --- Zoological Institute, GermanyFive species of Mormyrus Linné 1758, three from West Africa and one each from East and southern Africa, were compared morphologically, and their electric organ discharges (EODs) recorded in the field. The five species were morphologically well differentiated in terms... -
Temporal variations in the food habits of some fish species in Lake Nokoué, Benin
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: P Gnohossou --- Laboratoire d’Hydrobiologie et Aquaculture, Bénin P Lalèyè --- Laboratoire d’Hydrobiologie et Aquaculture, Bénin P Atachi --- Laboratoire d’Hydrobiologie et Aquaculture, Bénin G Magali --- Laboratoire EcoLab, UMR 5245 CNRS-UPS-INPT, France MC Villanueva --- Laboratoire d’Agronomie, Environnement et Écotoxicologie, France J Moreau --- Laboratoire d’Agronomie, Environnement et Écotoxicologie, FranceStomach contents of the 12 most abundant fish species in Lake Nokoué, Benin, collected between 2003 and 2005, were analysed for temporal variations in their diet. Several species showed seasonal shifts in their diets based on benthic prey abundance and... -
Seasonal Changes in Foliar Nutrient Content of E. grandis
Item type: Journal Article • Journal: South African Forestry Journal • Authors: A. P.G. Schönau --- ,The monthly variations in the concentrations of six macro- and four micro-nutrients in the foliage of Eucalyptus grandis were studied at three different sites for a period of two years, when the trees were between one and three years of... -
Is caudal fin colour in tigerfish Hydrocynus vittatus a sex or population trait?
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: M Soekoe --- Centre for Aquatic Research, Department of Zoology, South Africa FH van der Bank --- African Centre for DNA Barcoding, Department of Zoology, South Africa NJ Smit --- Water Research Group (Ecology), Unit for Environmental Sciences and Management, Potchefstroom Campus, South AfricaTigerfish caudal fin colours vary from yellow to red, with distinct dissimilarities previously noted. To understand these colour differences, tigerfish were collected during 2008 to 2010 from four southern African populations in the Upper Zambezi River (ZAM), Okavango Delta (OKA),... -
Influence of sample size and sampling frequency on the quantitative dietary descriptions of a predatory fish in the Benguela ecosystem
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: N. McQueen M. H. GriffithsSpatial and temporal variation in the diet and feeding intensity of snoek, Thyrsites atun, a top predator of the southern Benguela, was investigated to provide information on data requirements for accuracy of annual diets as inputs to ecosystem models. Appropriate... -
Diet of Cape fur seals Arctocephalus pusillus pusillus at three mainland breeding colonies in Namibia. 1. Spatial variation
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: S Mecenero J-P Roux LG Underhill MN BesterThe diet composition of Cape fur seals Arctocephalus pusillus pusillus was investigated from three breeding colonies in Namibia between January 1994 and April 2002 using scat analysis. Otolith numbers were corrected for those lost during digestion before determining the percentage... -
Diet of Cape fur seals Arctocephalus pusillus pusillus at three mainland breeding colonies in Namibia. 2. Temporal variation
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: S Mecenero J-P Roux LG Underhill SP KirkmanScat analysis was used to assess temporal variability in the diet composition of Cape fur seals Arctocephalus pusillus pusillus from three breeding colonies in Namibia (January 1994 to April 2002). The diet displayed significant inter- and intra-annual variation in composition... -
Distribution patterns of striped mullet Mugil cephalus in mangrove creeks, Zanzibar, Tanzania
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: AW Mwandya --- Department of Animal Sciences and Production, Tanzania YD Mgaya --- Department of Aquatic Sciences and Technology, Tanzania MC Öhman --- Department of Zoology, Sweden I Bryceson --- , Norway M Gullström --- Department of Zoology, SwedenSpatial and seasonal variations in density of striped mullet Mugil cephalus were investigated in four mangrove creeks in Zanzibar, Tanzania, during a one-year cycle. Fish were collected monthly in the lower, intermediate and upper reaches of each creek using a... -
Buoyancy-stirring interactions in a subtropical embayment: a synthesis of measurements and model simulations in Maputo Bay, Mozambique
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: JD Lencart e Silva --- , UK JH Simpson --- , UK AM Hoguane --- School of Marine and Coastal Sciences, Mozambique J-L Harcourt-Baldwin --- Department of Oceanography, South AfricaMaputo Bay, on the coast of Mozambique, is a tidally energetic, subtropical embayment in a region subjected to strong seasonal rainfall. Data from moored current meters, tide gauges and monthly bay-wide surveys were used to characterise the evolution of the... -
An investigation of the effect of temporal variation in growth rate of Umbrina robinsoni on biological reference point estimates calculated using per-recruit models
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: K Hutchings --- Department of Zoology and Marine Biology Research Centre, South Africa MH Griffiths --- Ministry of Fisheries, New Zealand SJ Lamberth --- Branch Fisheries, Department of Agriculture, Forestry and Fisheries, South AfricaThe effect of temporal variation in growth rate on per-recruit model outputs was investigated by comparing biological reference points obtained using growth curves derived for Umbrina robinsoni populations from False Bay, on the south coast of South Africa, sampled 10... -
Ecological distribution of the shrimp Nematopalaemon schmitti (Crustacea: Decapoda: Caridea) in three bays on the south-eastern coast of Brazil
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: AC Almeida --- NEBECC (Crustacean Biology, Ecology and Culture Study Group), Departamento de Zoologia, Brazil A Fransozo --- NEBECC (Crustacean Biology, Ecology and Culture Study Group), Departamento de Zoologia, Brazil GM Teixeira --- NEBECC (Crustacean Biology, Ecology and Culture Study Group), Departamento de Zoologia, Brazil KAN Hiroki --- NEBECC (Crustacean Biology, Ecology and Culture Study Group), Departamento de Zoologia, Brazil M Furlan --- NEBECC (Crustacean Biology, Ecology and Culture Study Group), Departamento de Zoologia, Brazil G Bertini --- , BrazilThe relationships between the spatial and temporal variations in the abundance of the shrimp Nematopalaemon schmitti and water temperature, salinity, and texture and organic-matter content of the sediment, were analysed in Ubatumirim, Ubatuba and Mar Virado bays on the northern... -
Oil yield and quality variation between sexes in Osyris lanceolata (African sandalwood) and its value as a fodder plant in Tanzania
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: PL Mwang’ingo --- Faculty of Science, Tanzania G Kibodya --- Faculty of Science, Tanzania AR Mng’ong’o --- , TanzaniaAfrican sandalwood (Osyris lanceolata) is widely harvested in East Africa for extraction of oil, which is used in the fragrance and perfumery industry. Over the years, harvesting of the species has been concentrated to female plants because it is claimed... -
Growth potential and genetic parameters of four Mesoamerican pines planted in the Southern Hemisphere
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: GR Hodge --- Department of Forestry and Natural Resources, USA WS Dvorak --- Department of Forestry and Natural Resources, USASummary results are reported from a total of 319 provenance/progeny tests of Pinus tecunumanii, P. maximinoi, P. patula and P. greggii that were established on sites in Brazil, Colombia and South Africa. Tests were measured for the growth traits height,... -
A preliminary study of allozyme differences amongst Carcharhinus sharks from the continental slope near Abidjan, Côte d'lvoire
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: Béatrice Adepo-Gourène Lounès Chikhi Jean-François Agnèse Germain Gourène Alain HervéGenetic variability of fifty-five shark specimens from the genus Carcharhinus was analysed using 18 allozyme loci. Sixteen loci were polymorphic either within, or between, species. Levels of genetic polymorphism, as measured by observed heterozygosity values, ranged from 0.008 (±0.008) to... -
Variation in benthic macroinvertebrate assemblages in Ologe Lagoon, Nigeria
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: TundeOT ImoobeThe community structure, diversity and seasonal variation of the benthic macroinvertebrates in Ologe Lagoon were studied at four sites during the dry and wet seasons of 2003 to provide environmental baseline data for the lagoon. The community comprised 29 taxa... -
Spatial and temporal variation in the macroinvertebrate community structure of the lower Elands River, Mpumalanga, South Africa
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: M Ferreira --- Centre for Aquatic Research, Department of Zoology, South Africa V Wepener --- Centre for Aquatic Research, Department of Zoology, South Africa JHJ van Vuren --- Centre for Aquatic Research, Department of Zoology, South AfricaThe Elands River, Mpumalanga, is an ecologically sensitive river that is constantly threatened by a variety of human activities. The influence of a pulp and paper mill on the river's macroinvertebrate assemblages was studied in March and June 2005, representing... -
Low allozyme variation in tigerfish Hydrocynus vittatus (Teleostei: Alestidae) from the Okavango panhandle, with notes on the selection of candidates for artificial breeding
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: M Soekoe --- Centre for Aquatic Research, Department of Zoology, South Africa NJ Smit --- Centre for Aquatic Research, Department of Zoology, South Africa H van der Bank --- Centre for Aquatic Research, Department of Zoology, South AfricaTo ensure the utilisation of optimal tigerfish gene pools for artificial propagation, the hypothesis that tigerfish from the Okavango system should have greater heterozygosity than those from smaller river systems was tested. This electrophoretic analysis provides the first report of... -
Further notes on age of first breeding, plumage and biometrics of kelp gulls in South Africa
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: PA WhittingtonAdult kelp gulls Larus dominicanus vetula were caught at the nest in the Eastern Cape region of South Africa, in October and November 2006 using a 'walk-in' trap. In all, 13 previously ringed birds were re-trapped and a known-aged colour-ringed... -
Seasonal nutrient fluctuation in selected plant species in the Kalahari
Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: FH Stapelberg MW van Rooyen J du P BothmaSeasonal changes in crude protein, phosphorus and calcium contents of five common plant species in the south-western Kalahari were investigated. Three species that are browsed by springbok (Acacia erioloba, Grewia flava and Rhigozum trichotomum) and two grass species (Schmidtia kalahariensis... -
Phenotypic plasticity and local adaptation in two extreme populations of Acacia karroo
Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: G Bayonne Mboumba D WardPhenotypic plasticity is the effect of growth variability in response to different environmental conditions. Adaptive phenotypic plasticity is more specific; it is the ability of a single genotype to produce an array of phenotypes depending on the environmental extent. We... -
Influence of mineral composition and rumen degradability of Atriplex nummularia (Hatfield Select F1) plants on selection preference of sheep
Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: WA van Niekerk --- Department of Animal and Wildlife Sciences, South Africa Abubeker Hassen --- Department of Animal and Wildlife Sciences, South Africa LD Snyman --- Department of Animal and Wildlife Sciences, South Africa NFG Rethman --- Department of Plant Production and Soil Science, South Africa RJ Coertze --- Department of Animal and Wildlife Sciences, South AfricaThis study examined intraspecific variation in mineral composition and rumen degradability of Atriplex nummularia plants and the influence on selection preferences of sheep. Individual plants were categorised into high, medium and least preference groups by assessing the order in which... -
Strongly Measurable Kurzweil-Henstock Type Integrable Functions and Series
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: V. MarraffaWe give necessary and sufficient conditions for the scalar Kurzweil-Henstock integrability and the Kurzweil-Henstock-Pettis integrability of functions f : [1, ∞) → X defined as f = ∑∞ n=1 xnχ [n,n+1). Also the variational Henstock integrability is considered. -
LULU operators for functions of continuous argument
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Roumen Anguelov Carl RohwerThe LULU operators, well known in the nonlinear multiresolution analysis of sequences, are extended to functions defined on a continuous domain, namely, a real interval. We show that the extended operators replicate the essential properties of their discrete counterparts. More... -
A model to determine the theoretical maximum feed speed of a frame saw
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: CB WesselsThe frame saw is a popular primary and secondary log breakdown saw in South Africa. In this study a theoretical model for estimating the maximum feed speed of a frame saw is derived. Contrary to earlier models, the actual blade... -
RAPD markers demonstrate genetic diversity in Pterocarpus angolensis from Zimbabwe and Zambia
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: E Chisha-Kasumu S Woodward A PriceUnderstanding the availability, extent and apportionment of genetic variability in natural populations of the southern African savanna tree Pterocarpus angolensis can provide reliable information on the evolutionary history and phylogenetic relationships of P. angolensis populations. This information will aid strategies... -
Comparative growth performance of different Australian provenances and local land races of Grevillea robusta at Lushoto and Ubiri in the West Usambara Mountains, Tanzania
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: LM Madadi --- Lushoto Silviculture Research Centre, Tanzania SC Mathias --- Lushoto Silviculture Research Centre, Tanzania WA Mugasha --- , Tanzania L Nshubemuki --- , Tanzania ST Mwihomeke --- Department of Forestry, South AfricaGrowth of seven Grevillea robusta provenances from its natural habitat in northern New South Wales and southern Queensland, Australia, and five local land races were studied at two trial sites established in November 1998 at Lushoto and Ubiri in the... -
Factors affecting diet, habitat selection and breeding success of the African Crowned Eagle Stephanoaetus coronatus in a fragmented landscape
Item type: Journal Article • Journal: Ostrich: Journal of African Ornithology • Authors: Christopher J Swatridge --- School of Biosciences, UK Ara Monadjem --- All Out Africa Research Unit, Department of Biological Sciences, Swaziland David J Steyn --- , South Africa Garth R Batchelor --- , South Africa Ian CW Hardy --- School of Biosciences, UKThis study aimed to identify variables that affect habitat selection and nesting success of the African Crowned Eagle Stephanoaetus coronatus, the largest forest raptor, in north-eastern South Africa. A preference for nesting in the Northern Mistbelt Forest vegetation type was... -
Genetic diversity and gene flow in Clarias gariepinus from Lakes Victoria and Kanyaboli, Kenya
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: JE Barasa --- Department of Fisheries and Aquatic Sciences, Kenya R Abila --- Department of Fisheries Management and Aquaculture Technology, Kenya JP Grobler --- Department of Genetics, South Africa OG Dangasuk --- Department of Biological Sciences, Molecular Genetics Section, Kenya MN Njahira --- Biosciences eastern and central Africa - International Livestock Research Institute Hub (BecA-ILRI Hub), Kenya B Kaunda-Arara --- Department of Fisheries and Aquatic Sciences, KenyaThe African catfish Clarias gariepinus is an important species in the rapidly expanding aquaculture industry in East Africa. Most Kenyan catfish farmers use stocks with unknown genetic characteristics, with uncertified seeds and inter-basin exchange of brood stocks threatening the genetic... -
Do SASS5 scores vary with season in the South African highveld? A case study on the Skeerpoort River, North West province, South Africa
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: HE Fourie --- Department of Zoology and Entomology, South Africa C Thirion --- Department of Water Affairs: Resource Quality Services, South Africa CW Weldon --- Department of Zoology and Entomology, South AfricaMacroinvertebrate assemblages can vary with season as a result of changing environmental conditions and phenology of individual species. The objective of this study was to determine whether results from the South African Scoring System version 5 (SASS5) are affected by... -
Spatio-temporal variation in density of microphytoplankton genera in two tropical coral reefs of Mauritius
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: SB Sadally --- Department of Biosciences, Faculty of Science, Mauritius N Taleb-Hossenkhan --- Department of Biosciences, Faculty of Science, Mauritius R Bhagooli --- Department of Biosciences, Faculty of Science, MauritiusSpatial and temporal (seasonal and interannual) variation in microphytoplankton was investigated at two tropical coral reef sites off Mauritius (Belle Mare [BM] and Flic-en-Flac [FEF]), from 2010 to 2012. Each site was divided into three zones: coast, lagoon and reef... -
Genetic variability of South African fiscal shrikes (Lanius collaris) across an altitudinal gradient
Item type: Journal Article • Journal: African Zoology • Authors: S. Soobramoney --- School of Biological & Conservation Sciences, University of KwaZulu-Natal, South Africa G.K. Campbell --- School of Life and Environmental Sciences, University of KwaZulu-Natal, South Africa C.T. Downs --- School of Biological & Conservation Sciences, University of KwaZulu-Natal, South Africa N.J. Adams --- School of Biological & Conservation Sciences, University of KwaZulu-Natal, South AfricaAn electrophoretic allozyme study of the fiscal shrike Lanius collaris, a widely distributed sub-Saharan passerine, was undertaken to investigate altitudinal variation in genetic structure within this species. It is a sedentary bird with limited dispersal so that subpopulations may be... -
Cephalopod diet of the Cape fur seal, Arctocephalus pusillus pusillus, along the Namibian coast: variation due to location
Item type: Journal Article • Journal: African Zoology • Authors: P.J.N. de Bruyn --- Mammal Research Institute, Department of Zoology and Entomology, South Africa M.N. Bester --- Mammal Research Institute, Department of Zoology and Entomology, South Africa S.P. Kirkman --- Mammal Research Institute, Department of Zoology and Entomology, South Africa S. Mecenero --- Avian Demography Unit, Department of Statistical Sciences, South Africa J.P. Roux --- Ministry of Fisheries and Marine Resources, Directorate of Resource Management, Lüderitz Marine Research, Namibia N.T.W. Klages --- Institute for Environmental and Coastal Management, Nelson Mandela Metropolitan University, South AfricaScats of the Cape fur seal, Arctocephalus pusillus pusillus, were sampled at four mainland colonies, Cape Cross, Atlas Bay,Wolf Bay and Van Reenen Bay, along the Namibian coast over a period of eight years (1994–2001) to assess the diversity and... -
Morphometric variation in the Tunisian green frog, Rana saharica Anura: Ranidae)
Item type: Journal Article • Journal: African Zoology • Authors: Nabil Amor --- Research Unit: Genetics, Biodiversity and Bio-Resources Development, Biotechnology Institute of Monastir, Tunisia Sarra Farjallah --- Research Unit: Genetics, Biodiversity and Bio-Resources Development, Biotechnology Institute of Monastir, Tunisia Khaled Said --- Research Unit: Genetics, Biodiversity and Bio-Resources Development, Biotechnology Institute of Monastir, TunisiaRana saharica is the most widely distributed anuran in Tunisia. We examined morphological variation in 124 specimens as a function of their geographical origin, using univariate and multivariate statistics with traditional morphometrics. Our results supported the existence of three morphotypes... -
Genetic variation in the Critically Endangered velvet worm Opisthopatus roseus (Onychophora: Peripatopsidae)
Item type: Journal Article • Journal: African Zoology • Authors: Savel R. Daniels --- Department of Botany and Zoology, South AfricaIn the present study the genetic variation of the Critically Endangered velvet worm species Opisthopatus roseus is examined. This species is endemic to the Ngele mistbelt forest in the KwaZulu-Natal province of South Africa. In recent years the forest has... -
Spatial and temporal variation in cadmium body loads of four intertidal invertebrates from False Bay, South Africa
Item type: Journal Article • Journal: African Zoology • Authors: A.J. Reinecke --- Department of Botany and Zoology, South Africa N.P. Mdzeke --- Department of Botany and Zoology, South Africa S.A. Reinecke --- Department of Botany and Zoology, South AfricaIncreasing urbanization and industrialization along the coastal areas of False Bay in South Africa can endanger coastal ecosystems because of increasing metal pollution. To obtain baseline data on contamination levels in the intertidal zone, cadmium (Cd) body loads of four... -
Determining adrenocortical activity as a measure of stress in African buffalo (Syncerus caffer) based on faecal analysis
Item type: Journal Article • Journal: African Zoology • Authors: A. Ganswindt --- Mammal Research Institute, Department of Zoology and Entomology, South Africa A.S.W. Tordiffe --- National Zoological Gardens of South Africa, South Africa E. Stam --- Mammal Research Institute, Department of Zoology and Entomology, South Africa M.J. Howitt --- National Zoological Gardens of South Africa, South Africa F. Jori --- Mammal Research Institute, Department of Zoology and Entomology, South AfricaLittle is known about the levels of stress experienced by African buffalos affected by injury, disease, or socio-ecological and anthropogenic factors. To be able to start filling this gap, we examined the suitability of two 11-oxoaetiocholanolone enzyme-immunoassays (EIAs) detecting 11,17... -
Solving the challenges of monitoring mobile populations: insights from studies of waterbirds in southern Africa
Item type: Journal Article • Journal: Ostrich: Journal of African Ornithology • Authors: Hannah L Thomas --- Percy FitzPatrick Institute, DST–NRF Centre of Excellence, South Africa Philip AR Hockey --- Percy FitzPatrick Institute, DST–NRF Centre of Excellence, South Africa Graeme S Cumming --- Percy FitzPatrick Institute, DST–NRF Centre of Excellence, South AfricaHighly mobile species are difficult to monitor. It is often unclear from abundance estimates whether a population is genuinely declining or simply elsewhere. If the spatial and temporal scales of monitoring are inadequate, the data will only be useful if... -
Temporal and spatial differences in three-egg clutch frequency of the African Black Oystercatcher
Item type: Journal Article • Journal: Ostrich: Journal of African Ornithology • Authors: Dane M Paijmans --- Percy FitzPatrick Institute of African Ornithology, DST–NRF Centre of Excellence, South Africa Douglas Loewenthal --- , Peter G Ryan --- Percy FitzPatrick Institute of African Ornithology, DST–NRF Centre of Excellence, South Africa Philip AR Hockey --- ,African Black Oystercatchers Haematopus moquini produce a modal clutch size of two eggs and only rarely lay three eggs. A review of over 4 000 nest records from across their breeding range (dating back to the early 1960s) revealed that... -
Phenotypic characterisation of sweetpotato genotypes grown in East and Central Africa
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: Rukundo Placide --- African Centre for Crop Improvement, South Africa Hussein Shimelis --- African Centre for Crop Improvement, South Africa Mark Laing --- African Centre for Crop Improvement, South Africa Daphrose Gahakwa --- Rwanda Agriculture Board, RwandaIdentification of genetic variability and interrelationships among germplasm collections is fundamental to select parents with complementary traits for plant breeding programmes. The aim of this study was to characterise and identify breeding parents among 54 sweetpotato genotypes grown in Rwanda,... -
Do aquatic macroinvertebrate communities respond to land-use effects in the Wilge River, Mpumalanga, South Africa?
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: K Farrell --- Golder Associates Africa (Pty) Ltd, South Africa JHJ van Vuren --- Department of Zoology, South Africa M Ferreira --- Department of Zoology, South AfricaAquatic macroinvertebrate community responses to the effects of various land uses were investigated in 2010–2013 in the Wilge River, a tributary of the Olifants River, South Africa. The catchment area is characterised by agricultural, mining and industrial activities, which potentially... -
Incorporating stable isotopes into a multidisciplinary framework to improve data inference and their conservation and management application
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: HM Christiansen --- Great Lakes Institute for Environmental Research, Canada AT Fisk --- Great Lakes Institute for Environmental Research, Canada NE Hussey --- Great Lakes Institute for Environmental Research, CanadaThrough its ability to address complex ecological questions and the possibility of analysing large sample sizes to understand population‑level processes, the use of stable isotope analysis (δ13C and δ15N) has grown rapidly in recent years. Importantly, it is now becoming... -
Macroinvertebrate variation in endorheic depression wetlands in North West and Mpumalanga provinces, South Africa
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: L Foster --- Department of Zoology, South Africa W Malherbe --- Water Research Group, Unit for Environmental Science and Management, South Africa M Ferreira --- Department of Zoology, South Africa JHJ van Vuren --- Department of Zoology, South AfricaAquatic macroinvertebrates are rarely used in wetland assessments due to their variation. However, in terms of biodiversity, these invertebrates form an important component of wetland fauna. Spatial and temporal variation of macroinvertebrate assemblages in endorheic depressions (locally referred to as... -
Seasonal and genotypic variation of water-soluble polysaccharide content in leaves of Cyclocarya paliurus
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: Xiangxiang Fu --- Co-Innovation Center for Sustainable Forestry in Southern China, China Xiaodong Zhou --- Co-Innovation Center for Sustainable Forestry in Southern China, China Bo Deng --- Co-Innovation Center for Sustainable Forestry in Southern China, China Xulan Shang --- Co-Innovation Center for Sustainable Forestry in Southern China, China Shengzuo Fang --- Co-Innovation Center for Sustainable Forestry in Southern China, ChinaCyclocarya paliurus (Batal) Iljinskaja is an important medicinal woody plant due to numerous bioactive natural products in its leaves. As an important bioactive natural product, water-soluble polysaccharides (WSP) in leaves of C. paliurus possess diverse biological activities, such as hypoglycemic,... -
Temporal changes in cranial size in South African vlei rats (Otomys): evidence for the ‘third universal response to warming’
Item type: Journal Article • Journal: African Zoology • Authors: Aluwani Nengovhela --- Department of Ecology and Resource Management, School of Environmental Sciences, South Africa Roderick M Baxter --- Department of Ecology and Resource Management, School of Environmental Sciences, South Africa Peter J Taylor --- South African Research Chair on Biodiversity Value and Change in the Vhembe Biosphere Reserve, School of Mathematics and Natural Sciences, South AfricaUsing museum collections and recently collected specimens we studied geographical and temporal (from 1906 to 2013) changes in skull size of two sibling species of rodents, Otomys auratus and O. angoniensis, in northern South Africa occupying distinct temperate grassland (O... -
Genetic variation across Tunisian populations of the anuran species Discoglossus pictus and Pelophylax saharicus
Item type: Journal Article • Journal: African Zoology • Authors: Nabil Amor --- Research Unit: Genetics, Biodiversity and Bio Resources Development, Biotechnology Institute of Monastir, Tunisia Guillermo Velo-Antón --- Department of Ecology and Evolutionary Biology, U.S.A Sarra Farjallah --- Research Unit: Genetics, Biodiversity and Bio Resources Development, Biotechnology Institute of Monastir, Tunisia Khaled Said --- Research Unit: Genetics, Biodiversity and Bio Resources Development, Biotechnology Institute of Monastir, TunisiaThe intraspecific variation of mitochondrial cytochrome b sequence was analysed for two widely distributed Tunisian anuran species, Discoglossus pictus and Pelophylax saharicus. We observed low genetic variation within both species (D. p. auritus 0.6% uncorrected genetic distances, P. saharicus 0.2%)... -
Ontogenetic variation and craniometric sexual dimorphism in the social giant mole-rat, Fukomys mechowii (Rodentia: Bathyergidae), from Zambia
Item type: Journal Article • Journal: African Zoology • Authors: C.T. Chimimba1 --- Department of Zoology and Entomology, South Africa A.M. Sichilima --- Department of Zoology and Entomology, South Africa C.G. Faulkes --- School of Biological and Chemical Sciences, U.K. N.C. Bennett --- Department of Zoology and Entomology, South AfricaThe degree of maxillary molar tooth-row eruption and wear were used to assign samples of the social giant mole-rat, Fukomys mechowii, from Zambia, into nine relative age classes in order to assess ontogenetic (age) variation and craniometric sexual dimorphism, with... -
Preliminary insights into the level of genetic variation retained in the endangered echo parakeet (Psittacula eques) towards assisting its conservation management
Item type: Journal Article • Journal: African Zoology • Authors: Tiawanna D. Taylor --- Institute of Genetics, University of Nottingham, U.K. David Y. Parkin --- Institute of Genetics, University of Nottingham, U.K.This study examined a suite of microsatellite markers, originally developed for other parrot species, for their usefulness in providing details about the amount of genetic variation that has been retained in the endangered echo parakeet of Mauritius. Biological samples were... -
Ingestion rates and grazing impact of the brackwater mussel Brachidontes virgiliae in Lake St Lucia, iSimangaliso Wetland Park, South Africa
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: HA Nel --- School of Life Sciences, South Africa R Perissinotto --- School of Life Sciences, South Africa NK Carrasco --- School of Life Sciences, South AfricaBivalves feed on a combination of phytoplankton and zooplankton and have the potential to impact considerably the planktonic biomass, especially when they occur in high densities, such as in oyster and mussel beds. The brackwater mussel Brachidontes virgiliae is numerically... -
Temporal and spatial fluctuations of heavy metals in Opa Reservoir, Ile-Ife, Nigeria
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: TA Adesakin --- Department of Zoology, Nigeria AA Adedeji --- Department of Zoology, Nigeria YF Taiwo --- Natural History Museum, NigeriaThe Opa Reservoir, established for water supply to the Obafemi Awolowo University community, over the years has received direct linkage to township drains as a result of the widening and dredging of its river channels. The current study aimed at... -
Variation in body size and morphometric traits of males and females of the wall gecko, Tarentola delalandii (Phyllodactylidae) from different environments on Tenerife
Item type: Journal Article • Journal: African Journal of Herpetology • Authors: María de Fuentes-Fernández --- , Spain María Mercedes Suárez-Rancel --- , , Spain Miguel Molina-Borja --- , SpainWe analysed sexual dimorphism in body size and several other morphological traits of two populations of Tarentola delalandii on the island of Tenerife (San Cristóbal de La Laguna in the North, and Granadilla de Abona in the South), whose habitats... -
Appendicular skeleton of the vestigial-limbed African skink Eumecia anchietae
Item type: Journal Article • Journal: African Journal of Herpetology • Authors: Shane G. Stanley --- , , USA Rachel M. Liniewski --- , , USA Philip J. Senter --- , , USAWithin the lizard family Scincidae (the skinks) are numerous examples of species with vestigial limbs and girdles, but these vestigial structures remain undescribed for many such species. Here we seek to partially fill this gap in knowledge by describing the... -
Morphological variation in the Sabota Lark Calendulauda sabota in southern Africa
Item type: Journal Article • Journal: Ostrich: Journal of African Ornithology • Authors: Sean M Marr --- Department of Biodiversity, South Africa Mmatjie L Mashao --- Department of Biodiversity, South Africa G Derek Engelbrecht --- Department of Biodiversity, South AfricaSeparation of the eight southern African subspecies of Sabota Lark Calendulauda sabota into thick-billed and slender-billed groups has been proposed. This study used biometric data obtained from museum skins in South Africa to evaluate morphological variation in the subspecies as... -
Genetic diversity and differentiation of the Western Leopard Toad (Sclerophrys pantherina) based on mitochondrial and microsatellite markers
Item type: Journal Article • Journal: African Journal of Herpetology • Authors: Jessica M. da Silva --- , , South Africa Kevin A. Feldheim --- , , USA G. John Measey --- , , South Africa Stephen Doucette-Riise --- , , South Africa Ryan J. Daniels --- , , South Africa Lucas F. Chauke --- , , South Africa Krystal A. Tolley --- , , South AfricaIntraspecific genetic diversity provides the basis for evolutionary change and is therefore considered the most fundamental level of biodiversity. Mitochondrial DNA (mtDNA) and microsatellite loci are the markers most typically used in population-level studies; however, their patterns of genetic variation... -
Broad- and narrow-sense heritabilities in a South African cloned open-pollinated Eucalyptus grandis breeding population
Item type: Journal Article • Journal: Southern Hemisphere Forestry Journal • Authors: CL Snedden CZ Roux SD VerrynGenetic variances and heritabilities of a 66-month old cloned Eucalyptus grandis breeding population of families, derived from open-pollinated selections, were estimated. The genetic variance for the growth traits was largely additive genetic variance, whereas the proportion of non-additive genetic variance... -
Assessment of water quality in selected shallow wells of Keiyo Highlands, Kenya
Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: Peter K. Mbaka --- Department of Civil, Construction and Environmental Engineering, Kenya John K. Mwangi --- Department of Civil, Construction and Environmental Engineering, Kenya Clement K. Kiptum --- Department of Civil and Structural Engineering, KenyaA supply of potable water is important for the sustenance of a healthy population. This study was conducted in the Keiyo Highlands, Elgeyo Marakwet County, in Kenya. The aim was to assess seasonal variation in physico-chemical and microbiological water quality... -
Significant genetic differentiation among meroplanktonic barrel jellyfish Rhizostoma pulmo (Cnidaria: Scyphozoa) in the Mediterranean Sea
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: AR Ben Faleh --- Marine Biology Unit, Faculty of Sciences of Tunis, Tunisia H Allaya --- Marine Biology Unit, Faculty of Sciences of Tunis, Tunisia A Armani --- FishLab, Department of Veterinary Sciences, Italy AAB Shahin --- Department of Zoology, Faculty of Science, EgyptMolecular data have shown that jellyfishes are more geographically restricted and evolutionarily divergent than previously thought. We examined genetic variation and divergence within the meroplanktonic barrel jellyfish Rhizostoma pulmo in the Mediterranean Sea; specific sampling areas were the northern Adriatic,... -
Variation in selected solid wood properties of young Pinus patula from diverse sites in the Mpumalanga escarpment area in South Africa
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: Barry G Muller --- Nelson Mandela Metropolitan University, South Africa Josua H Louw --- Nelson Mandela Metropolitan University, South Africa Francois S Malan --- Research Centre, South Africa (retired)Regression analyses identified ‘Growth Days’ (an index expressing site moisture availability) as the only site variable contributing significantly to the prediction to wood density (R2 = 0.57), whereas the model predicting grain angle included only ‘Altitude’ (R2 = 0.60). These... -
Contrasting hydrography and phytoplankton distribution in the upper layers of cyclonic eddies in the Mozambique Basin and Mozambique Channel
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: T Lamont --- Branch: Oceans and Coasts, Department of Environmental Affairs, South Africa RG Barlow --- Marine Research Institute and Department of Oceanography, South AfricaHydrographic data collected in cyclonic eddies in the Mozambique Channel and Basin revealed notable differences in temperature and salinity at a depth of 100 m, the upper mixed layer, the nitracline depths, and vertical distribution of chlorophyll-a (Chl-a). Differences in... -
Seasonal habitat requirements of Lemon Dove (Aplopelia larvata) in coastal forest: camera-trap surveys of a reclusive species
Item type: Journal Article • Journal: African Zoology • Authors: David A Ehlers Smith --- School of Life Sciences, South Africa Yvette C Ehlers Smith --- School of Life Sciences, South Africa Colleen T Downs --- School of Life Sciences, South AfricaThe modification of natural habitats requires behavioural plasticity, which may be challenging for ‘specialist’ species. Quantifying habitat requirements and behavioural responses of specialists to landscape transformation is thus a priority for baseline data to inform conservation practices. Using camera-trap surveys... -
Genotypic variation in tree growth and selected flavonoids in leaves of Cyclocarya paliurus
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: Yanni Cao --- College of Forestry, China Bo Deng --- College of Forestry, China Shengzuo Fang --- College of Forestry, China Xulan Shang --- College of Forestry, China Xiangxiang Fu --- College of Forestry, China Wanxia Yang --- College of Forestry, ChinaCyclocarya paliurus is a valuable medicinal tree species in China. However, limited information is available on its genotype selection and cultivation for improvement of growth and health-promoting phytochemicals. To contribute to improved knowledge of the potential use of the species,... -
Spatio-seasonal dynamics of bacteria and metal composition of a platinum mine tailings dam, Rustenburg, South Africa
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: Molemi E Rauwane --- Agricultural Research Council–Biotechnology Platform, South Africa Laurette M Marais --- Department of Biotechnology, Faculty of Applied and Computer Sciences, Vanderbijlpark Campus, South Africa Oluwatosin G Oladipo --- Unit for Environmental Sciences and Management, South Africa Cornelius C Bezuidenhout --- Unit for Environmental Sciences and Management, South Africa Mark S Maboeta --- Unit for Environmental Sciences and Management, South AfricaSeasonal variations and proximity to polluted sites, among other factors, play a vital role in soil composition. The impact of spatio-seasonal changes on bacterial and heavy metal content on and around the platinum mine tailings dam, Rustenburg, South Africa, was... -
Superficial location of the brachial plexus and axillary artery in relation to pectoralis minor: a case report
Item type: Journal Article • Journal: Southern African Journal of Anaesthesia and Analgesia • Authors: K Keet --- Division of Clinical Anatomy and Biological Anthropology, Department of Human Biology, South Africa G Louw --- Division of Clinical Anatomy and Biological Anthropology, Department of Human Biology, South AfricaKnowledge of the anatomy of the infraclavicular fossa is important as this region is a target site for anaesthesia of the upper limb during infraclavicular approaches to brachial plexus blocks and in central venous cannulation of the axillary or subclavian... -
Effects of seasonal variation, group size and sex on the activity budget and diet composition of the addax antelope
Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: Hicham Seri --- Laboratoire d’Elevage et de la Faune Sauvage, Tunisia Mohsen Chammem --- Laboratoire d’Elevage et de la Faune Sauvage, Tunisia Luis MM Ferreira --- CITAB-Centre for the Research and Technology of Agro-Environment and Biological Sciences, Portugal Marwa Kechnebou --- Laboratoire d’Elevage et de la Faune Sauvage, Tunisia Touhami Khorchani --- Laboratoire d’Elevage et de la Faune Sauvage, Tunisia Severiano R Silva --- CECAV-Animal Science Department, PortugalBehaviour and diet composition are critical elements in conservation biology within the scope of reintroduction programs. Here we focused on addax (Addax nasomaculatus), a Critically Endangered antelope species, in the Jbil National Park, Tunisia. In this study, we advanced the... -
Concentrations and ecological risks of metals in surface sediments of some coastal creeks in the Niger Delta, Nigeria
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: CMA Iwegbue --- Department of Chemistry, Nigeria OV Beecroft --- Department of Chemistry, Nigeria JE Ogala --- Department of Geology, Nigeria FE Egobueze --- Environment Department, Nigeria GO Tesi --- Department of Chemistry, Nigeria GE Nwajei --- Department of Chemistry, Nigeria BS Martincigh --- School of Chemistry and Physics, South AfricaThe concentrations of nine metals were measured by atomic absorption spectrophotometry in surface sediments of three coastal creeks, namely, the Ifie, Egbokodo and Ubeji creeks, in the Niger Delta of Nigeria, from August 2012 to January 2013. The aim of... -
Radial variation of wood properties in Neolamarckia cadamba trees from an East Java community forest
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: Yus Andhini Bhekti Pertiwi --- Faculty of Agriculture, Japan Haruna Aiso --- Faculty of Agriculture, Japan Futoshi Ishiguri --- Faculty of Agriculture, Japan Sri Nugroho Marsoem --- Faculty of Forestry, Indonesia Shinso Yokota --- Faculty of Agriculture, JapanRadial variations in wood properties, cell morphologies and cell proportions were investigated for nine 4-year-old Neolamarckia cadamba trees planted in a community forest in East Java, Indonesia. The relationships between stem diameter and wood properties, cell morphologies or cell proportions... -
Intraspecific morphological divergence in two Cichlid species from Benin
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: Luke M Bower --- Program in Ecology and Evolutionary Biology and Department of Wildlife and Fisheries Sciences, USA Laith A Jawad --- Freelance Fish Biodiversity Consultant, New Zealand Pierre M Gnohossou --- Département d’Aménagement et Gestion de Ressources Naturelles, Republic of Benin Ayoko Géraldine Tossou --- Département d’Aménagement et Gestion de Ressources Naturelles, Republic of BeninSelection on morphological traits can vary across the range of species, inducing a mosaic of phenotypes across populations. Intraspecific morphological divergence had been demonstrated for many fish groups inhabiting environments with varying abiotic or biotic selective pressures. Such intraspecific phenotypic... -
Food profile of Grey Wagtail Motacilla cinerea during an annual cycle in the Algerian Babors Mountains of North Africa
Item type: Journal Article • Journal: Ostrich: Journal of African Ornithology • Authors: Roza Belkacem --- Laboratoire de Zoologie Appliquée et d’Écophysiologie Animale, Faculté des Sciences de la Nature et de la Vie, Algeria Abdelazize Franck Bougaham --- Laboratoire de Zoologie Appliquée et d’Écophysiologie Animale, Faculté des Sciences de la Nature et de la Vie, Algeria Mohammed Gagaoua --- Université Clermont Auvergne, France Riadh Moulaï --- Laboratoire de Zoologie Appliquée et d’Écophysiologie Animale, Faculté des Sciences de la Nature et de la Vie, AlgeriaThis study showed from the analysis of 180 droppings of the Grey Wagtail Motacilla cinerea harvested during a period of one year from the Babors Mountains (Bejaia, Algeria) that insects formed the main part of the diet (85.9% of identified... -
Morphological differentiation among populations of Sarotherodon melanotheron melanotheron Rüppell 1852 across the West African Lagoon systems (Benin, Cameroon, Nigeria, Togo)
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: MO Popoola --- Department of Zoology, Nigeria FDB Schedel --- SNSB-Bavarian State Collection Zoology, Germany MA Akintoye --- Department of Zoology, NigeriaMorphometric variation among populations of Sarotherodon melanotheron melanotheron across its natural range (Mahin, epe, Lekki, Apese, Kuramo, Lagos, Iyagbe, Ologe, Badagry, Yewa – Nigeria; Be Lagoon – Togo; Idenau – Cameroon, Aheme – Benin; Portonovo – Benin) were studied to... -
Water level fluctuations in Lake Baringo, Kenya, during the 19th and 20th centuries: Evidence from lake sediments
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: EO Okech --- Biological Sciences, Kenya N Kitaka --- Biological Sciences, Kenya S Omondi --- Biological Sciences, Kenya D Verschuren --- Biology, BelgiumThis article presents a fossil diatom-based, semi-quantitative reconstruction of water level fluctuations for Lake Baringo over the past 200 years as a consequence of climatic variations. A 285 cm long sediment core sample was collected using a Rod-Operated Single-drive Stationary... -
Spatial and temporal variation in the use of supplementary food in an obligate termite specialist, the bat-eared fox
Item type: Journal Article • Journal: African Zoology • Authors: Keafon R Jumbam --- Department of Zoology and Entomology, South Africa Stéphanie Périquet --- Department of Zoology and Entomology, South Africa Fredrik Dalerum --- Research Unit of Biodiversity, Spain Aliza le Roux --- Department of Zoology and Entomology, South AfricaThe bat-eared fox (Otocyon megalotis) is considered a termite specialist. However, studies of its diet have been limited to indirect methods, such as scat and stomach content analyses, resulting in intraspecific dietary variations due in part to methodological differences. Because... -
A panel-data analysis of the explanatory power of factor premiums on the Johannesburg Stock Exchange (JSE)
Item type: Journal Article • Journal: Investment Analysts Journal • Authors: Daniel Page --- Finance Division, School of Economic & Business Sciences, South Africa Christo Auret --- Finance Division, School of Economic & Business Sciences, South AfricaA large portion of South African asset pricing literature considers the identification of investment styles present on the Johannesburg Stock Exchange (JSE). Unfortunately, the identification of an ‘investment style’ does not necessarily entail that the said style is an ‘explanatory... -
Cranial variation in common dolphins Delphinus spp. off South Africa, with the inclusion of information from the holotype of Delphinus capensis
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: SG Ngqulana --- Department of Zoology, South Africa S Plön --- Earth Stewardship Science Research Institute – Africa Earth Observatory Network, South Africa A Galatius --- Department of Bioscience, Denmark P Pistorius --- Department of Zoology, South Africa GJG Hofmeyr --- Department of Zoology, South AfricaThe common dolphins (genus Delphinus) are widely distributed in all temperate and tropical oceans. Over this wide geographical distribution they show considerable range in morphological variation, which has led to descriptions of several species in the genus. Until recently, only... -
Prevalence of Kudoa thyrsites (Myxozoa) in South African sardine Sardinops sagax, kingklip Genypterus capensis, and Cape hakes Merluccius capensis and M. paradoxus
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: SS Henning --- Department of Food Science and Technology, South Africa M Krügel --- Department of Food Science, South Africa M Manley --- Department of Food Science, South AfricaPrevalence of infection with the myxozoan parasite Kudoa thyrsites is not well documented in sardine Sardinops sagax, the Cape hakes Merluccius capensis and M. paradoxus, and kingklip Genypterus capensis. Quantitative polymerase chain reaction assays were used to determine the prevalence... -
Meta-analysis of average costs of HIV testing and counselling and voluntary medical male circumcision across thirteen countries
Item type: Journal Article • Journal: African Journal of AIDS Research • Authors: Carlos Pineda-Antunez --- Center for Health Systems Research, Mexico Gisela Martinez-Silva --- Center for Health Systems Research, Mexico Diego Cerecero-Garcia --- Center for Health Systems Research, Mexico Lily Alexander --- Department of Global Health, USA Drew B Cameron --- Health Policy and Management, USA Chris Chiwevu --- Independent consultant, Lalit Dandona --- Public Health Foundation of India, Gurugram, National Capital Region, India Carol Dayo Obure --- Department of Global Health and Development, London School of Hygiene and Tropical Medicine, UK Steven Forsythe --- Avenir Health, USA Van Thu Nguyen --- FHI 360, Vietnam Stella Settumba --- The Kirby Institute, University of New South Wales, Australia Michel Tchuenche --- Avenir Health, USA Hoang Van Minh --- Center for Population Health Sciences, Vietnam James G Kahn --- Philip R. Lee Institute for Health Policy Studies, USA Gabriela Gomez --- Department of Global Health and Development, London School of Hygiene and Tropical Medicine, UK Sedona Sweeney --- Department of Global Health and Development, London School of Hygiene and Tropical Medicine, UK Anna Vassall --- Department of Global Health and Development, London School of Hygiene and Tropical Medicine, UK Lori Bollinger --- Avenir Health, USA Carol Levin --- Department of Global Health, USA Sergio Bautista-Arredondo --- Center for Health Systems Research, MexicoObjective: Explore facility-level average costs per client of HIV testing and counselling (HTC) and voluntary medical male circumcision (VMMC) services in 13 countries. -
Diversity analysis of mungbean (Vigna radiata) germplasm using a semi-graphical technique
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: Hafiz Basheer Ahmad --- Oilseed Research Institute, Ayub Agricultural Research Institute, Pakistan Salsabeel Rauf --- Oilseed Research Institute, Ayub Agricultural Research Institute, Pakistan Waqas Shafqat Chattha --- Department of Plant Breeding and Genetics, Pakistan Busharat Hussain --- Pulses Research Institute, Ayub Agricultural Research Institute, Pakistan Iqtidar Hussain --- Department of Agronomy, Pakistan Irfan Rasool --- Pulses Research Institute, Ayub Agricultural Research Institute, PakistanGrain legumes such as mungbean are often co-cultivated with cereals. The genetic diversity among 84 mungbean genotypes was studied using metroglyph and principal component analysis. Data were recorded for days to flowering and maturity, plant height, pods per plant, clusters... -
Locally high, but regionally low: the impact of the 2014–2016 drought on the trees of semi-arid savannas, South Africa
Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: AM Swemmer --- , South AfricaDrought is thought to be a factor limiting the abundance of shrubs and trees in savannas, but this has rarely been tested empirically. The severe drought of 2014–2016 provided an opportunity to document the impact of drought on the mortality... -
The influence of host dispersal on the gene flow and genetic diversity of generalist and specialist ectoparasites
Item type: Journal Article • Journal: African Zoology • Authors: Conrad A Matthee --- , South AfricaThe dispersal and subsequent gene flow within parasite species is the result of a complex interaction between parasite life history, host life history and abiotic environmental factors. To gain more insights into the drivers responsible for parasite dispersal, COI mtDNA... -
Stand structure, regeneration and seed dispersal patterns of Nothofagus glauca (Hualo) in central Chile
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: Rafael Navarro-Cerrillo --- , España Antonio Cabrera-Ariza --- , Chile Antonio Avaria --- , Chile Guillermo Palacios-Rodríguez --- , España Rómulo Santelices-Moya --- , ChileGrowing interest in functional silviculture is promoting new approaches to the study of seed dispersal and regeneration, two of the key processes that determine the structure and dynamics of plant populations. Nothofagus glauca is an obligate-seeding tree species typical of... -
A comparison of experimental designs for cultivar evaluations
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: Hae Saul --- , South Africa M Booyse --- , South Africa PA Swanepoel --- , South AfricaSpatial heterogeneity and the lack of clear or significant treatment responses in agricultural field experiments complicates recommending the most suitable cultivar(s) to producers for a specific area. Increased attention should be given to the experimental design of cultivar trials, as... -
Genetic diversity assessment of sorghum (Sorghum bicolor (L.) Moench) landraces using SNP markers
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: Girma Mengistu --- , South Africa Hussein Shimelis --- , South Africa Mark Laing --- , South Africa Dagnachew Lule --- , South Africa Ermias Assefa --- , Ethiopia Isack Mathew --- , South AfricaSystematic genetic profiling of the genetic pool is fundamental to select desirable parents for conventional and genomic-assisted breeding. The objective of this study was to assess genetic variation and population structure in a diverse population of sorghum (Sorghum bicolor (L.)... -
Numbers of invasive House Sparrows Passer domesticus in a rural landscape of Limpopo province, South Africa
Item type: Journal Article • Journal: Ostrich: Journal of African Ornithology • Authors: Cavin T Shivambu --- , South Africa Ndivhuwo Shivambu --- , South Africa Takalani Nelufule --- , South Africa Moleseng C Moshobane --- , South Africa Manqoba M Zungu --- , South Africa Colleen T Downs --- , South AfricaThe House Sparrow Passer domesticus is recognised as one of the commonest avian invasive species globally, with its occurrence associated with human existence. However, relatively little on population sizes of this species in rural landscapes has been documented. The study... -
Trends in chemical pollution and ecological status of Lake Ziway, Ethiopia: a review focussing on nutrients, metals and pesticides
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: LB Merga --- , The Netherlands AA Mengistie --- , Ethiopia JH Faber --- , The Netherlands PJ Van den Brink --- , The NetherlandsAquatic ecosystems contribute to human well-being by delivering ecosystem services, but their protection has been given low priority in Africa. Lake Ziway in the Ethiopian Rift Valley basin provides services including irrigation, drinking water and fish food in the region... -
Intercolony health evaluation of wild African penguins Spheniscus demersus, in relation to parasites, along the southwest coast of South Africa
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: MPA Espinaze --- , South Africa C Hui --- , South Africa L Waller --- , South Africa S Matthee --- , South AfricaClinical parameters of African penguins Spheniscus demersus have been recorded mostly from birds admitted to rehabilitation centres and are typically presented as mean values across a region. It is uncertain whether these values are representative of wild penguins and whether... -
Phylogeography and morphometric variation of the Spike-heeled Lark Chersomanes albofasciata complex
Item type: Journal Article • Journal: Ostrich: Journal of African Ornithology • Authors: SM Miller --- , South Africa KN Barnes --- , South Africa P Bloomer --- , South Africa PG Ryan --- , South AfricaThe Spike-heeled Lark Chersomanes albofasciata is a peculiar, short-tailed lark confined to southern, central and East Africa. Typical of resident larks, it exhibits marked geographic variation in plumage colour, which has historically resulted in large numbers of subspecies being described... -
Colonial versus solitary breeding: nesting patterns of Brown-throated Martins Riparia paludicola in Morocco
Item type: Journal Article • Journal: Ostrich: Journal of African Ornithology • Authors: Peter W Greig-Smith --- , United KingdomThis study explored reasons for variable nesting habits in a hole-nesting bird species that sometimes breeds colonially and sometimes alone. Nesting was surveyed over ten years in natural sand cliffs and similar features created by human activity along a river... -
Phytoplankton community structure in relation to physico-chemical factors in a tropical soda lake, Lake Shala (Ethiopia)
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: Solomon Wagaw --- , Ethiopia Seyoum Mengistou --- , Ethiopia Abebe Getahun --- , EthiopiaPhytoplankton communities responses to physico-chemical factors were studied in Lake Shala from January to December 2018. Distinct spatial and seasonal variations were observed for all physico-chemical parameters, except DO (ANOVA: p < 0.05). In total, 72 taxa, Bacillariophyta (55 taxa),... -
Are Cape Cormorants Phalacrocorax capensis losing the competition? Dietary overlap with commercial fisheries
Item type: Journal Article • Journal: Ostrich: Journal of African Ornithology • Authors: OB Masiko --- , South Africa PG Ryan --- , South Africa CD van der Lingen --- , South Africa L Upfold --- , South Africa S Somhlaba --- , South Africa M Masotla --- , South Africa Y Geja --- , South Africa BM Dyer --- , South Africa RJM Crawford --- , South Africa AB Makhado --- , South AfricaCape Cormorants Phalacrocorax capensis breed in southern Africa’s Benguela upwelling system and in 2013 were listed as Endangered by the IUCN following a population decrease of >50% over their three most recent generations. This decrease was associated with reduced prey... -
Adoption of formal HIV and AIDS workplace policies: An analysis of industry/sector variations
Item type: Journal Article • Journal: SAHARA-J: Journal of Social Aspects of HIV/AIDS • Authors: Rhoda Bakuwa --- Human Resources Management, Malawi Polytechnic,Addressing HIV and AIDS is the responsibility of many stakeholders including private sector companies. However, increasing evidence reveals that the majority of companies around the world are yet to acknowledge and respond to HIV and AIDS as a workplace issue... -
Frequency of tail autotomy in the African Olive Grass Snake, Psammophis ‘phillipsii’ from three habitats in southern Nigeria
Item type: Journal Article • Journal: The Journal of the Herpetological Association of Africa • Authors: GodfreyC. Akani --- Rivers State University of Science and Technology, Nigeria Luca Luiselli --- F.I.Z.V. (Ecology) and Centre of Environmental Studies “Demetra”, Italy SundayM. Wariboko --- Rivers State University of Science and Technology, Nigeria Linda Ude --- F.I.Z.V. (Ecology) and Centre of Environmental Studies “Demetra”, Italy FrancescoM. Angelici --- F.I.Z.V. (Ecology) and Centre of Environmental Studies “Demetra”, Italy -
On the identification and distribution of the two‐striped night adder (Causus bilineatus) and related forms
Item type: Journal Article • Journal: African Journal of Herpetology • Authors: Jens Bødtker Rasmussen --- University of Copenhagen, DenmarkAn examination of material of Causus bilineatus Boulenger 1905 and of its sympatric congeners from south central Africa confirms its distinctness. Comparisons of allopatric populations of C. bilineatus indicate that the variation in number of ventral and subcaudal scutes is... -
Zooplankton distribution and community structure as a function of environmental variables in the Niger River and its tributaries in Niger
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: H Souley Adamou --- Université de Toulouse, France B Alhou --- Université Abdou Moumouni de Niamey, Niger M Tackx --- Université de Toulouse, France F Azémar --- Université de Toulouse, FranceThe Niger River and its main tributaries (Sirba, Tapoa and Mékrou) in Niger were sampled during high and low water flow with the objectives of (1) comparing the taxonomic structure, diversity and abundance of the zooplankton community (rotifers, copepods, crustaceans)... -
Ekeland, Takahashi and Caristi principles in preordered quasi-metric spaces
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: S. Cobzaş --- Babeş-Bolyai University, RomaniaWe prove versions of Ekeland, Takahashi and Caristi principles in pre-ordered quasi-metric spaces, the equivalence between these principles, as well as their equivalence to some completeness results for the underlying quasi-metric space. These extend the results proved in S. Cobzaş,... -
Status of diversity, abundance and seasonal variations of gill net catches of cichlids in Lake Bosumtwi, Ghana
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: A Asase --- University of Ghana, Ghana TL Lauridsen --- Aarhus University, Denmark PO Sanful --- University of Energy and Natural Resources, Ghana EEK Quansah --- University of Ghana, Ghana FKE Nunoo --- University of Ghana, GhanaThe cichlids in Lake Bosumtwi are under increasing pressure with a recent build-up in local fishing pressure. This study was conducted to assess the status and seasonal catch rates of fish species using gillnets over a two-year period. Four species... -
Multiplicity of positive solution for Schrödinger-Poisson system with p-Laplacian
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Weiqiang Zhang --- Lanzhou University, People’s Republic of China Peihao Zhao --- Lanzhou University, People’s Republic of ChinaIn this paper, we consider the positive solutions for a Schrödinger-Poisson system containing p-Laplacian and Poisson equation. With a local condition on the potential, by using penalization method, Nehari manifold and Ljusternik-Schnirelmann category theory, the multiplicity and concentration of solutions... -
Solutions of an anisotropic elliptic problem involving nonlinear terms
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: A. Razani --- Imam Khomeini International University, Iran T. Soltani --- Imam Khomeini International University, IranUsing variational methods, the existence and multiplicity of weak solutions for the following Neumann anisotropic problem -
Existence and regularity results for a degenerate elliptic nonlinear equation on weighted Sobolev spaces
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Mohsen Alimohammady --- University of Mazandaran, Iran Carlo Cattani --- University of Tuscia, Italy Morteza Koozehgar Kalleji --- Arak University, IranThis paper deals with the existence of many solutions a degenerate weighted elliptic equation which its the number of solutions depend on degeneracy term a i.e., the number of subdomains of Ω\a −1(0) whose boundary is made by submanifolds with... -
Testing the thermal melanism hypothesis for Cape Cobras (Naja nivea) using community science photographic data
Item type: Journal Article • Journal: African Journal of Herpetology • Authors: Jody M Barends --- University of Johannesburg, South Africa Kim J Scholtz --- University of the Western Cape, South AfricaAnimal colour is a highly adaptive phenotypic trait that can respond to several selection pressures, including those facilitated by variations in climate. The thermal melanism hypothesis predicts that for ectotherms, selection for darker phenotypes should be highest in cooler areas... -
Two-step inertial Tseng’s extragradient method for solving quasimonotone variational inequalities
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: O.T. Mewomo --- University of KwaZulu-Natal, South Africa R.N. Nwokoye --- University of KwaZulu-Natal, South Africa C.C. Okeke --- University of the Witwatersrand, South AfricaWe focus on quasimonotone variational inequality problems with non-Lipschitz operator and combine some operator theory techniques to establish a weak convergent fixed point iterative method to approximate the solution of the presented problems. The convergence analysis assumes very mild conditions... -
Multiplicity of solutions for variable-order fractional Kirchhoff problem with singular term
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: R. Chammem --- University of Tunis el Manar, Tunisia A. Sahbani --- University of Tunis el Manar, Tunisia A. Saidani --- University of Monastir, TunisiaIn this paper, we consider a class of singular variable-order fractional Kirchhoff problem of the form: -
Cape genet Genetta tigrina diet in the Albany Thicket Biome, South Africa
Item type: Journal Article • Journal: African Zoology • Authors: Axola Plaatjie --- University of Fort Hare, South Africa Filipe Carvalho --- University of Fort Hare, South Africa Rabelani Marikhele --- University of the Witwatersrand, South Africa Zimkitha JK Madikiza --- University of the Witwatersrand, South Africa Emmanuel Do Linh San --- University of Fort Hare, South AfricaThe diet of the Cape genet Genetta tigrina is only well known in the coastal forests of South Africa, where either arthropods or small mammals are their dominant prey. Here, we aimed to demonstrate this species’ opportunistic behaviour by investigating... -
Spatial and seasonal variation of microplastics and surface water quality of the Njoro River and Lake Nakuru ecosystems, Kenya
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: Petra Kienyiy Chui --- Egerton University, Kenya Bernard Kibet Kirui --- Egerton University, Kenya Meshack Amos Obonyo --- Egerton University, KenyaHigh levels of plastic pollutants threaten aquatic habitats as the plastic materials are ingested by aquatic organisms as food. This study assessed seasonal variations of microplastics and the water quality of the Njoro River and Lake Nakuru, Kenya. Selected water... -
Patterned, plain, and in-between: An assessment of ecogeographic divergence between colour pattern morphs of the common egg-eater Dasypeltis scabra
Item type: Journal Article • Journal: African Journal of Herpetology • Authors: Jody M. Barends --- University of Johannesburg, South Africa Ielhaam Bassier --- University of the Western Cape, South Africa Emma E. Buckley --- University of the Western Cape, South Africa Cora S. Stobie --- National Museum, South Africa Michael F. Bates --- National Museum, South AfricaIntraspecific variation in colour patterns may reflect adaptive responses to local environmental regimes that favour selection of different trade-offs between visual communication, thermoregulation, and anti-predatory functions. Understanding the drivers of colour pattern variation within species can therefore provide valuable insights... -
Contrast in larval sensitivity to low pH in sea urchins from neighbouring seagrass meadows at Inhaca Island, Mozambique
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: JA Duvane --- Eduardo Mondlane University, Mozambique D Cossa --- Eduardo Mondlane University, Mozambique DC de Abreu --- Eduardo Mondlane University, Mozambique M Mafambissa --- Eduardo Mondlane University, Mozambique MP Scarlet --- Eduardo Mondlane University, Mozambique A Macia --- Eduardo Mondlane University, Mozambique S Dupont --- University of Gothenburg, SwedenOcean acidification presents a major threat to marine life, and a large body of evidence has documented its negative effects on various marine species and ecosystems. Recent meta-analyses highlight the key role of local adaptation and have linked species’ sensitivity... -
Space and spatially structured environmental variables account for variation in blackfly and mayfly communities in sub-tropical South African rivers
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: PA Ramulifho --- University of South Africa, South Africa SH Foord --- University of Venda, South Africa NA Rivers-Moore --- University of KwaZulu-Natal, South AfricaUsing aquatic invertebrate assemblages for bioassessment of streams and rivers is a fast and cost-effective approach to studying the impact of environmental stressors in aquatic ecosystems. The use of aquatic invertebrates is premised on their predictable responses to environmental stressors... -
Greenhouse gas concentrations in tropical wetlands of the Cross River estuary, Nigeria
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: AB Andem --- University of Calabar, Nigeria OB Ojo --- University of Calabar, Nigeria RA Odey --- University of Calabar, Nigeria GE Eni --- University of Calabar, Nigeria OR Ibor --- University of Calabar, Nigeria IA Iwara --- University of Calabar, Nigeria VO Eyo --- Nigerian Maritime University, NigeriaThe Cross River estuary is a coastal wetland in the south-eastern part of the Niger Delta region of Nigeria with its hydrological cycle largely dependent on precipitation. The purpose of this study was to determine the greenhouse gas (GHG) concentrations... -
Bayesian forecasting of stock returns on the JSE using simultaneous graphical dynamic linear models
Item type: Journal Article • Journal: Investment Analysts Journal • Authors: Nelson Kyakutwika --- Stellenbosch University, South Africa Bruce Bartlett --- Stellenbosch University, South AfricaCross-series dependencies are crucial in obtaining accurate forecasts when forecasting a multivariate time series. Simultaneous Graphical Dynamic Linear Models (SGDLMs) are Bayesian models that elegantly capture cross-series dependencies. This study forecasts returns of a 40... -
Stability and performance of Bambara groundnut (Vigna subterranea (L.) Verdc.) genotypes in different South African environments
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: Sithembile Kunene --- University of KwaZulu-Natal, Pietermaritzburg campus, College of Agriculture, Engineering and Science, School of Agricultural Earth, and Environmental Sciences, South Africa Abe Shegro Gerrano --- Agricultural Research Council, Vegetable, Industrial and Medicinal Plants, South Africa Alfred Oduor Odindo --- University of KwaZulu-Natal, Pietermaritzburg campus, College of Agriculture, Engineering and Science, School of Agricultural Earth, and Environmental Sciences, South AfricaGlobal food security faces challenges arising from population growth, climate change, and the prevalence of monoculture agriculture. In addressing these concerns, Bambara groundnut (Vigna subterranean (L.) Verdc.) emerges as a promising crop due to its nutritional richness and resilience in... -
A critical point approach to non-local complex systems of fractional discrete equations
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Massimiliano Ferrara --- University Mediterranea of Reggio Calabria, Italy Shapour Heidarkhani --- Razi University, Iran Shahin Moradi --- Razi University, IranDiscrete fractional equations have emerged across various fields such as science, engineering, economics, and finance to better capture the characteristics of non-local complex systems. In this discussion, we explore the existence of at least three unique solutions for discrete fractional... -
Colorimetric changes in two radial positions caused by wood-decaying fungi in wood of seven eucalypt species
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: Pedro Nicó de Medeiros Neto --- Federal University of Campina Grande, Brazil Juarez Benigno Paes --- Federal University of Espírito Santo, Brazil João Gabriel Missia da Silva --- Federal University of Espírito Santo, Brazil Fabricio Gomes Gonçalves --- Federal University of Espírito Santo, Brazil Daniela Minini --- Federal University of Paraná, Brazil Libânia da Silva Ribeiro --- Federal University of Campina Grande, Brazil Fernanda Dalfiôr Maffioletti --- Federal University of Espírito Santo, BrazilThis research aimed to determine the colorimetric alterations of the wood of seven eucalypt species caused by fungal decay in two positions in the pith–bark direction (median heartwood and transition region, containing the heartwood and sapwood), during wood exposure to... -
Seasonal effects on surface water quality in the Awetu River, Ethiopia
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: Mohammedsalih Kadir Gobana --- Jimma University, Ethiopia Alemayehu Haddis Getahun --- Jimma University, Ethiopia Dessalegn Dadi Olani --- Jimma University, EthiopiaUnderstanding the impact of seasonal variation on surface water provides a better understanding of pollution dynamics and the implementation of sustainable water-use and management strategies. The objective of this study was to assess the impact of seasonal variation on surface... -
Growth patterns and condition index of rock oysters Saccostrea cucullata in relation to river influence in southeastern Madagascar
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: M Masimana --- Institut d’Enseignement Supérieur d’Anôsy, Université de Toliara, Madagascar A Andrisoa --- Aix-Marseille University, CNRS, IRD, INRAE, CEREGE, FranceSaccostrea cucullata is the dominant species of rock oyster (family Ostreidae) in southeastern Madagascar. Despite its economic and ecological importance, information on its biology and ecology is scarce. This study investigated the growth, shell length–weight relationship, and condition index (tissue... -
Intrapopulation isotopic niche structure in mammalian carnivores and herbivores across contrasting habitats
Item type: Journal Article • Journal: African Zoology • Authors: Chanel Lewis --- University of the Free State, South Africa Runè van der Merwe --- University of the Free State, South Africa Chabi AMS Djagoun --- University of Abomey-Calavi, Benin Etotépé A Sogbohossou --- University of Abomey-Calavi, Benin Daryl Codron --- University of the Free State, South AfricaNatural communities exhibit ecological gradients that result in a variety of competitive interactions and variations in niche patterns. Changes in resource availability affect the size of a species’ niche: it expands when a variety of resources are abundant and contracts... -
Phenotypic variance in an acoustic signal: a potentially sexually selected behaviour in Cape Clapper Larks Corypha apiata
Item type: Journal Article • Journal: Ostrich: Journal of African Ornithology • Authors: Zofia Wardynska --- Imperial College London, United Kingdom Holly Bennett --- Imperial College London, United Kingdom Xavier JM Mahele --- Imperial College London, United Kingdom Saskia IL Pearce --- Imperial College London, United Kingdom Ksenia Potapova --- Imperial College London, United Kingdom Sue Anne Zollinger --- Manchester Metropolitan University, United Kingdom Julia Schroeder --- Imperial College London, United KingdomCourtship displays provide important insight into sexual selection, evolution and the roles of communication signals in behavioural ecology. Any trait indicating individual quality must display phenotypic variation. Studying this variation can provide insight into the uses of acoustic cues in... -
Spatiotemporal shape variation in sagittal otoliths of spotted grunter Pomadasys commersonnii in South African estuaries
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: V Coetzee --- Department of Biological Sciences, University of Cape Town, South Africa S Kerwath --- Department of Biological Sciences, University of Cape Town, South Africa S Lamberth --- Department of Forestry, Fisheries and the Environment (DFFE), South Africa D Parker --- Department of Biological Sciences, University of Cape Town, South AfricaThe morphological structure of fish otoliths is under dual regulation by genetic and environmental factors, and has been successfully used to aid stock delineation. This study examined whether differences in sagittal otolith shape outlines could be used to delineate potential...
