Search
Search results for
We found
35 results for you
-
Effect of cyanamide and DNOC/oil on budbreak, yield and fruit size of Golden Delicious apples
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: M. North --- , Republic of South AfricaCalcium cyanamide (CaCN2), hydrogen cyanamide (H2CN2) and DNOC/oil (dinitro-o-cresol/oil emulsion) were evaluated as rest-breaking agents on Golden Delicious apples during two seasons and in two climatic zones. In the moderate climatic zone, a double and single application of DNOC/oil gave... -
Genotypic response to chilling period of apple buds from two Western Cape localities
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: P.J. Halgryn --- Department of Horticultural Science, Republic of South Africa K.I. Theron --- Department of Horticultural Science, Republic of South Africa N.C. Cook --- Department of Horticultural Science, Republic of South AfricaOne-year-old, ca. 40 cm long shoots of various apple cultivars were selected from commercial orchards in both the Elgin [34°S, 305 m, ca. 750 Utah Chill Units (CU)] and Koue Bokkeveld (33°S, 945 m, ca. 1300 CU) regions of 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. -
Phenology of woody plants in riverine thicket and its impact on browse availability to game species
Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: BB Janecke --- Animal, Wildlife and Grassland Sciences, South Africa GN Smit --- Animal, Wildlife and Grassland Sciences, South AfricaThe study area was located in the central Free State Grassland biome, but the vegetation partially represented riparian thicket. Leaf carriage patterns of deciduous species were determined from September 2004 to August 2008. Similarities existed between Acacia karroo and Diospyros... -
Strategies for the selection of uncontaminated Eucalyptus explants for shoot multiplication in a temporary immersion system (RITA®) in a commercial laboratory
Item type: Journal Article • Journal: The Southern African Forestry Journal • Authors: M. P. Watt M. Banasiak T. Nicholson B. McAlisterThe potential high yields of Eucalyptus shoot multiplication achieved with a temporary immersion culture system such as RITA® are compromised by losses caused by microbial contamination particularly bacteria, characteristic of the explants used to initiate the cultures. Disinfection of the... -
Seasonal and diurnal stratification in two small Zimbabwean reservoirs
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: Tamuka Nhiwatiwa BrianE MarshallSeasonal and diurnal stratification patterns were studied in two small Zimbabwe reservoirs. The water level of the upper reservoir fluctuated more than that of the lower one and theoretical water retention times were 9 days and 3.6 days, respectively. Rainfall... -
Distribution, breeding phenology and time budget of Ruddy Shelduck Tadorna ferruginea during the annual cycle in the Hauts Plateaux, north-east Algeria
Item type: Journal Article • Journal: Ostrich: Journal of African Ornithology • Authors: Mouloud Boulkhssaïm --- Department of Biology, Algeria Abdallah Ouldjaoui --- Department of Biology, Algeria AhmedH Alfarhan --- Center of Excellence for Research in Biodiversity, Saudi Arabia Boudjéma Samraoui --- Center of Excellence for Research in Biodiversity, Saudi ArabiaBetween September 2003 and July 2006, the reproductive biology and time budget of the Ruddy Shelduck Tadorna ferruginea was studied in the wetland complex of Oum el Bouaghi, north-east Algeria. Our results indicate a marked post-breeding dispersal of the Ruddy... -
Breeding phenology and moult of the endemic Bannerman's Weaver Ploceus bannermani
Item type: Journal Article • Journal: Ostrich: Journal of African Ornithology • Authors: Yahkat Barshep --- AP Leventis Ornithological Research Institute, Nigeria Shiiwua A Manu --- AP Leventis Ornithological Research Institute, NigeriaThe breeding phenology and moult cycle of the vulnerable and range-restricted Bannerman's Weaver Ploceus bannermani was studied on the Obudu Plateau in the eastern region of Nigeria. The peak breeding season was between August and October; a major cause of... -
Uptake and accumulation of ammonium by Alexandrium catenella during nutrient pulses
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: Y Collos M Lespilette A Vaquer M Laabir A PastoureaudField observations in Thau Lagoon, southern France, indicate that the growth of natural populations of Alexandrium catenella during blooms is limited by nitrogen and exhibits a storage rather than a growth response to an ammonium pulse. Therefore, ammonium uptake and... -
A hard-knock life: the foraging ecology of Cape cormorants amidst shifting prey resources and industrial fishing pressure
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: MH Hamann --- DST/NRF Centre of Excellence at the Percy FitzPatrick Institute of African Ornithology, South Africa D Grémillet --- DST/NRF Centre of Excellence at the Percy FitzPatrick Institute of African Ornithology, South Africa PG Ryan --- DST/NRF Centre of Excellence at the Percy FitzPatrick Institute of African Ornithology, South Africa F Bonadonna --- , France CD van der Lingen --- Department of Agriculture, Forestry and Fisheries, South Africa L Pichegru --- DST/NRF Centre of Excellence at the Percy FitzPatrick Institute of African Ornithology, South AfricaOnce one of the most numerous seabirds of the Benguela upwelling system, the population of Cape cormorants Phalacrocorax capensis has decreased by 60% in the past three decades and the species is listed as Near Threatened. Declines in prey availability... -
Comparative morphology of the oropharyngeal cavity of clinid fish (Perciformes: Clinidae), with particular attention to the form, number and distribution of taste buds, and dentition
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: O Gon L Fishelson Y DelareaThe present study compares the form, number and distribution of taste buds (TB) in the oropharyngeal cavity (OC) of 17 species of clinid fish (Perciformes, Blennioidei, Clinidae) from different geographical regions (Australia, Taiwan, South Africa), and includes observations on dentition... -
Causes for the recent increase in sea surface salinity in the north-eastern Gulf of Guinea
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: CY Da-Allada --- International Chair in Mathematical Physics and Applications [ICMPA – UNESCO Chair], Bénin G Alory --- Université de Toulouse; Université Paul Sabatier [UPS]; Laboratoire d'Etudes en Géophysique et Océanographie Spatiales [LEGOS], France Y du Penhoat --- International Chair in Mathematical Physics and Applications [ICMPA – UNESCO Chair], Bénin J Jouanno --- Institut Pierre-Simon Laplace [IPSL], France MN Hounkonnou --- Université de Toulouse; Université Paul Sabatier [UPS]; Laboratoire d'Etudes en Géophysique et Océanographie Spatiales [LEGOS], France E Kestenare --- Institut de Recherche pour le Développement [IRD], FranceIn situ sea surface salinity (SSS) observations showed an increase >0.5 over the period 2002–2009 in the Gulf of Guinea, off the Niger Delta. Observed changes in the Niger River runoff were not consistent with this increase in SSS, but... -
Status and diurnal activity budget of non-breeding White-headed Ducks Oxyura leucocephala in Algeria
Item type: Journal Article • Journal: Ostrich: Journal of African Ornithology • Authors: Nedjwa Meziane --- Laboratoire de Recherche et de Conservation des Zones Humides, Algeria Farrah Samraoui --- Laboratoire de Recherche et de Conservation des Zones Humides, Algeria Boudjéma Samraoui --- Laboratoire de Recherche et de Conservation des Zones Humides, AlgeriaIn Algeria, the Globally Endangered White-headed Duck Oxyura leucocephala is resident throughout the year in the coastal wetlands of north-east Algeria and the Hauts Plateaux, where it occupies habitats that range from freshwater ponds and brackish marshes to hypersaline lakes... -
Effectiveness of a Buddy intervention support programme for suicidal behaviour in a primary care setting
Item type: Journal Article • Journal: South African Family Practice • Authors: SS Naidoo --- Faculty of Health Sciences, South Africa P Gathiram --- Faculty of Health Sciences, South Africa L Schlebusch --- Faculty of Health Sciences, South AfricaBackground: Suicidal behaviour is a major contributor to the health burden globally. Non-fatal suicidal behaviour may be 10–40 times more frequent than fatal suicidal behaviour. National responses to this crisis have been variable. This study was designed to evaluate and... -
Sexual disparity in activity patterns and time budgets of angulate tortoises (Chersina angulata) on Dassen Island, South Africa
Item type: Journal Article • Journal: African Zoology • Authors: Toby Keswick --- Department of Biodiversity and Conservation Biology, South Africa Brian T. Henen --- Department of Biodiversity and Conservation Biology, South Africa Margaretha D. Hofmeyr --- Department of Biodiversity and Conservation Biology, South AfricaBehavioural frequencies and time budgets for male and female Chersina angulata were recorded in spring, September 2004. The daily activity of the population was 10.51 ± 0.42 h (mean ± CI), but individual males and females were in the open... -
Is a reduction in the individual vigilance of mothers a key evolutionary driver of group formation in white rhinos?
Item type: Journal Article • Journal: African Zoology • Authors: Adrian M. Shrader --- School of Life Sciences, University of KwaZulu-Natal, South Africa Julie F. Post --- Department of Zoology & Entomology, South Africa Nicole Hagenah --- School of Life Sciences, University of KwaZulu-Natal, South Africa Philip W. Bateman --- Department of Environment and Agriculture, Western AustraliaA key benefit and evolutionary driver of group living is reduced predation risk. In white rhinos, groups comprise adult females, their calves and one to six unrelated subadults. Subadults benefit from group living through exposure to novel areas, and protection... -
The occurrence of taste buds in adults of the terrestrial ceacilian Boulengerula boulengeri Tornier, 1898 (Lissamphibia: Gymnophiona: Herpelidae)
Item type: Journal Article • Journal: African Zoology • Authors: Karolina A. Budzik --- Department of Comparative Anatomy, Poland Krystyna Żuwała --- Department of Comparative Anatomy, Poland G. John Measey --- Department of Zoology, South AfricaTwo generations of gustatory organs occur during amphibian ontogeny in frogs and salamanders (Anura and Caudata), and are classified as taste buds or taste discs. Taste buds are present in larval forms, whereas taste discs are typical for adults. The... -
Capital budgeting: A case study analysis of the role of formal evaluation techniques in the decision making process
Item type: Journal Article • Journal: South African Journal of Accounting Research • Authors: E Gilbert --- Graduate School of Business, University of Cape Town,This paper furthers the understanding of capital budgeting by reviewing two individual capital investment decisions taken by manufacturing firms in South Africa. This study indicates that managers do not base their capital investment decisions on a comparison of the expected... -
An Analysis of the Approaches used by Industrial Companies Listed on the JSE to Identify their Cost of Capital
Item type: Journal Article • Journal: De Ratione • Authors: A S Pocock --- Mann Pocock and Associates, C de J Correia --- University of Cape Town, M P Wormald --- University of Cape Town,In order to maximise shareholder’s wealth, financial managers need to estimate their firm’s cost of capital. This paper, which is based on the results of a questionnaire sent to industrial companies listed on the JSE, examines both the acceptance and... -
Reckoning the risks and rewards of fertilizer micro-dosing in a sub-humid farming system in Tanzania
Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: Lutengano Mwinuka --- Department of Economics and Statistics, Tanzania Khamaldin Daud Mutabazi --- School of Agricultural Economics and Business Studies, Tanzania Jeremia Makindara --- School of Agricultural Economics and Business Studies, Tanzania Stefan Sieber --- Leibniz Centre for Agricultural Landscape Research (ZALF) e. V., GermanySmallholder farmers are reluctant to risk investing in fertilizers. To understand how risk is perceived and how economic returns are distributed before the decision to invest in fertilizer use is made, needs a systematic approach using localized applications. This study... -
Different Orders of Pleasure: Good Life and Human Flourishing in the City in Dambudzo Marechera’s Scrapiron Blues
Item type: Journal Article • Journal: Eastern African Literary and Cultural Studies • Authors: Edwin Mhandu --- English Department, South AfricaIn this article, I argue that Dambudzo Marechera’s Scrapiron Blues demonstrates different and varied orders of enjoyment and well-being in the city that challenge the authenticity and truthfulness of the narration of the enjoyment space(s) sanctioned by the ZANU PF... -
Diurnal activity patterns of Harwood’s Spurfowl Pternistis harwoodi in relation to habitat types and climatic conditions in the Central Highlands of Ethiopia
Item type: Journal Article • Journal: Ostrich: Journal of African Ornithology • Authors: Abadi Mehari Abrha --- Department of Animal, Rangeland and Wildlife Sciences, Ethiopia Shimelis Aynalem Zelelew --- Department of Fisheries, Ethiopia Habtu Kiros Nigus --- Department of Statistics, Ethiopia Aschalew Alelign --- Department of Animal, Rangeland and Wildlife Sciences, EthiopiaHarwood’s Spurfowl Pternistis harwoodi is an endemic bird of Ethiopia. Globally, it is categorised as Vulnerable. Habitat loss and hunting are the major conservation threats to the species. This study investigated the activity patterns of Harwood’s Spurfowl in relation to... -
The cost-effectiveness of using latrine dehydrated and pasteurization pellets and struvite: Experimental evidence from South Africa
Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: Benjamin Chapeyama --- School of Agricultural, Earth and Environmental Sciences, South Africa Edilegnaw Wale --- School of Agricultural, Earth and Environmental Sciences, South Africa Alfred Odindo --- School of Agricultural, Earth and Environmental Sciences, South AfricaFaecal sludge and urine can be recycled and processed into usable fertilizer products such as the latrine dehydrated and pasteurization (‘LaDePa’) pellets and struvite, respectively. To quantitatively determine the financial cost effectiveness of using LaDePa and struvite, a study was... -
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... -
Financial Profitability of Carbon Offset Monoculture Plantation Forestry on Smallholder Farms in Trans Mara Sub-County, Kenya
Item type: Journal Article • Journal: East African Agricultural and Forestry Journal • Authors: J. Chemuliti --- Kenya Agricultural and Livestock Research Organization, Kenya C. Ackello-Ogutu --- Department of Agricultural Economics, Kenya S. Mbogoh --- Department of Agricultural Economics, Kenya P. Irungu --- Department of Agricultural Economics, KenyaThere is growing interest in the development of smallholder carbon offset forestry projects in Africa as a means of mitigating climate change while providing co-benefits of development and environmental protection and conservation. Financial profitability of carbon projects is a key... -
On the financial interpretation of risk contributions: An analysis using Quantile Simulation
Item type: Journal Article • Journal: Investment Analysts Journal • Authors: Simon du Plooy --- Centre for Business Mathematics and Informatics, Faculty of Natural Sciences, South AfricaThis paper tests whether the financial interpretation of risk contributions (Qian, 2006), as measured by marginal change in volatility, holds when accounting for fat tails in the asset return distributions. This important result is the theoretical foundation of risk-based portfolios,... -
The population dynamics of four grass species in relation to burning in the KwaZulu-Natal Drakensberg
Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: Colin S Everson --- , South Africa Terry M Everson --- , South Africa Craig D Morris --- , South AfricaMarked tillers of Heteropogon contortus, Trachypogon spicatus, Tristachya leucothrix and Harpochloa falx were sampled regularly over a two-year period in Highland Sourveld burnt annually in winter and biennially in spring. Parameters recorded were height of shoot apex, tiller mass, number... -
The time-activity budgets of breeding Blue Swallows Hirundo atrocaerulea and the effects of weather on nestling growth
Item type: Journal Article • Journal: Ostrich: Journal of African Ornithology • Authors: Steven W Evans --- , South AfricaThe Blue Swallow is an intra-African migrant that breeds in its fragmented range from South Africa to southern Tanzania, from October to March annually. The birds migrate north and are on their non-breeding range in NE DRC, Uganda, NW Tanzania... -
Influence of soil organic carbon, fertiliser management, and weeding regime on weed dynamics and maize productivity on sandy soils in eastern Zimbabwe
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: Justin Chipomho --- , Zimbabwe Cosmas Parwada --- , Zimbabwe Joyful T Rugare --- , Zimbabwe Stanford Mabasa --- , Zimbabwe Regis Chikowo --- , Zimbabwe Arnold B Mashingaidze --- , ZimbabweLabour bottlenecks and multiple operations at the start of a cropping season often result in inadequate early weed control and subsequent poor crop performance. Therefore, there is a need to establish management practices that provide the best opportunities for the... -
Soil management for carbon sequestration
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: Rattan Lal --- , United StatesAn increase in atmospheric CO2 by ∼146% and global temperature by ∼1 °C since the year ca. 1750 has created an urgency to identify potential sinks for storage of excess CO2. The historic depletion of soil organic carbon (SOC) from... -
Rural infrastructure and production efficiency of food crop farmers: Implication for rural development in Nigeria
Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: Abeeb Babatunde Omotoso --- , Nigeria Saidat Adebola Daud --- , Nigeria Luke Okojie --- , Nigeria Abiodun Olusola Omotayo --- , South AfricaThis study investigated the impact of rural infrastructure on production efficiency of food crop rural farmers in Ogun State, Nigeria. A total of 160 farming households from 20 communities in Abeokuta and Ilaro in Ogun State Agricultural Development Programme (OGADEP)... -
Fire and herbivory shape belowground bud banks in a semi-arid African savanna
Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: AB Bombo --- , Brazil F Siebert --- , South Africa A Fidelis --- , BrazilFire and herbivory are major drivers in tropical savanna ecosystems and they selected a flora composed of species able to cope with recurrent aboveground biomass removal. Renewal of the herbaceous stratum is made possible by resprouting, mostly through a belowground... -
The effects of temperature on oxygen consumption in the lizard Pseudocordylus melanotus from Suikerbosrand Nature Reserve
Item type: Journal Article • Journal: African Journal of Herpetology • Authors: Suzanne McConnachie --- , , South AfricaIn reptiles, metabolic rate (MR) is affected by many different factors, including temperature, sex, body size and digestive state. Standard MR was measured for the lizard Pseudocordylus melanotus over a range of temperatures (20, 22, 25, 30 and 32°C). I... -
Tracking error volatility and relative risk budgets
Item type: Journal Article • Journal: Investment Analysts Journal • Authors: Aron Gottesman --- Pace University,This paper uses a pooled cross-sectional sample of actively managed US equity mutual funds from 1991–2022 to show that tracking error volatility (TEV) is characterised by reversion. Mutual funds with relatively high (low) TEV tend to reduce (increase) their TEV... -
Belowground resprouting potential and nutrient acquisition traits of three perennial grasses during the short dry season in Kenya
Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: Edwin M Kakusu --- University of Nairobi, Kenya RN Kinuthia --- University of Nairobi, Kenya Jacqueline P Ott --- , USA OK Koech --- University of Nairobi, KenyaSurvival of perennial grasses between wet seasons depends on the maintenance of belowground buds and root systems. Belowground bud and root traits were evaluated in three perennial grasses (Pennisetum mezianum (Leeke), Digitaria macroblephara (Hack. ex Schinz) Paoli, and Themeda triandra...