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A comparison of five methods for assessing veld condition in the natal midlands
Item type: Journal Article • Journal: Journal of the Grassland Society of Southern Africa • Authors: C A H Heard --- Department of Grassland Science, N M Tainton --- Department of Grassland Science, J Clayton --- Department of Grassland Science, M B Hardy --- Department of Agriculture (Natal Region),Site rankings obtained from five methods of scoring veld condition in the highland sourveld and the moist tall grassveld of the Natal Midlands were correlated with rankings from methods of multivariate analysis. With few exceptions, all methods gave rankings which... -
Identification and selection of benchmark sites on litholitic soils of the western grassland biome of South Africa
Item type: Journal Article • Journal: Journal of the Grassland Society of Southern Africa • Authors: O.J.H. Bosch --- Department Botany, F.P. Janse van Rensburg --- Department Botany, S. du T. Truter --- Department Botany,An approach to identify benchmarks for different ecological situations in the grassland biome is described. The approach is illustrated by using information on vegetation change, role of habitat factors and the relative palatability differences between the species of the vegetation... -
Ecological status of species on grazing gradients on the shallow soils of the western grassland biome in South Africa
Item type: Journal Article • Journal: Journal of the Grassland Society of Southern Africa • Authors: O.J.H. Bosch --- Department Botany, F.P. Janse vanRensburg --- Department Botany,Grasses on the shallow soils of the western grassland biome of South Africa were classified on their ecological status on the basis of their reaction to grazing. Vegetation data were gathered in such a way that those of different successional... -
An evaluation of veld condition assessment techniques in Highland Sourveld
Item type: Journal Article • Journal: Journal of the Grassland Society of Southern Africa • Authors: M.B. Hardy --- Department of Agriculture (Natal Region), Republic of South Africa C.R. Hurt --- Department of Agriculture (Natal Region), Republic of South AfricaAn evaluation of six methods used to index veld condition showed that the majority provided indices that were insensitive to long‐term grazing impact. However, certain species were found to either increase or decrease in relative abundance with an increase in... -
A weighted key species method for monitoring changes in species composition of Highland Sourveld
Item type: Journal Article • Journal: Journal of the Grassland Society of Southern Africa • Authors: C.R. Hurt --- Department of Agriculture (Natal Region), Republic of South Africa M.B. Hardy --- Department of Agriculture (Natal Region), Republic of South AfricaThe use of key species for indexing veld condition in relation to the fire/grazing impact has potential for monitoring change in the Highland Sourveld of Natal. Weightings are calculated for previously identified key species. A weighted‐averages approach is used in... -
Influence of habitat differences on the ecological grouping of grass species on a grazing gradient
Item type: Journal Article • Journal: Journal of the Grassland Society of Southern Africa • Authors: FranciP. Janse van Rensburg --- Department of Agriculture & Water Supply, Republic of South Africa O.J.H. Bosch --- Department of Botany, Republic of South AfricaThe ecological grouping (Decreaser and Increaser groups) of individual species was determined on two topographical units in the Highland Sourveld of the Orange Free State. For this purpose gradients were selected, giving special attention to fence‐line comparisons, vegetation at different... -
Use of multivariate techniques to identify vegetation units and monitor change on a livestock production system in a semi‐arid savanna of the eastern Cape
Item type: Journal Article • Journal: Journal of the Grassland Society of Southern Africa • Authors: J.C. Martens --- Departmentof Agricultural Development (Eastern Cape Region), Republic of South Africa J.E. Danckwerts --- Departmentof Agricultural Development (Eastern Cape Region), Republic of South Africa G.C. Stuart‐Hill --- Departmentof Agricultural Development (Eastern Cape Region), Republic of South Africa A.J. Aucamp --- Departmentof Agricultural Development (Eastern Cape Region), Republic of South AfricaSpecies composition data of the grass layer were determined from point surveys along permanently demarcated transects. These data were separated into vegetation units using multivariate techniques. The repeatability of this classification was tested on data collected over a period of... -
A comparison of some range condition assessment techniques used in southern African grasslands
Item type: Journal Article • Journal: Journal of the Grassland Society of Southern Africa • Authors: C.R. Hurt --- Natal Region, Department of Agricultural Development, Republic of South Africa O.J.H. Bosch --- Department of Plant Sciences, Republic of South AfricaTechniques currently used to assess range condition in the grassland biome of southern Africa are reviewed. The methods were used to calculate range condition indices from fire‐climax and climatic‐climax grassland data. These indices were then used to evaluate each method... -
The use of degradation gradients for the assessment and ecological interpretation of range condition
Item type: Journal Article • Journal: Journal of the Grassland Society of Southern Africa • Authors: O.J.H. Bosch --- Department of Plant and Soil Sciences, Republic of South Africa H.G. Gauch --- Department of Soil, Crop and Atmospheric Sciences, United States of AmericaMultivariate procedures were used to subdivide the southern African climatic climax grasslands of the 700–800‐mm rainfall zone into relatively homogeneous grazing areas. A degradation gradient was constructed for each of these areas. This was done by means of centred PCA... -
Plant species dynamics in the Southern Tall Grassveld under grazing, resting and fire
Item type: Journal Article • Journal: Journal of the Grassland Society of Southern Africa • Authors: C.D. Morris --- Department of Grassland Science, Republic of South Africa N.M. Tainton --- Department of Grassland Science, Republic of South Africa M.B. Hardy --- Department of Agricultural Development (Natal Region), Republic of South AfricaAn analysis of temporal changes in botanical composition in a long‐term grazing trial indicates that species dynamics in the Southern Tall Grassveld of Natal are determined by the specific combination of grazing, mowing and fire impacts. Species composition of a... -
The effects of topo-edaphic variables and cultivation on the woody vegetation of Weenen Nature Reserve, KwaZulu-Natal
Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: L Breebaart TG O'Connor JC Hughes CD Morris IA RushworthThe soil types and woody vegetation of Weenen Nature Reserve (WNR), KwaZulu-Natal, were described. Mispah, overlying shale, and Shortlands, overlying dolerite were the most common of 18 the soil forms encountered. Six vegetation types were identified by TWINS PAN which... -
Quantified range condition assessment of open Camelthorn savanna along a degradation gradient
Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: I Zimmermanno FP Graz MH Berry NNT Imasiku ND Muroua MM Sibalatani CS SikopoMeasurements were taken at 20 different sites in a relatively homogenous area of open Camelthorn savanna in eastern Namibia. Ordination of grass species composition did not provide a good degradation gradient, due to domination by different species of annual grasses... -
Ecological effects of fire-breaks in the montane grasslands of the southern Drakensberg, South Africa
Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: TG O'Connor RG Uys AJ MillsFire-breaks, by legislation, are burnt annually before mid-winter in the southern Drakensberg, affecting 5–10% of the landscape, and resulting in marked selection for the early season flush by both livestock and wildlife. This study investigated whether this severe defoliation regime... -
A degradation gradient for the assessment of rangeland condition of a semi-arid sourveld in southern Africa
Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: HC van der Westhuizen HA Snyman HJ FouchéData collected between 1986/87 and 1999/2000 from a long-term rangeland monitoring project on three different sites were used to construct a degradation gradient in a semi-arid sour grassland of southern Africa. The degradation gradient was then used to quantify rangeland... -
Identification of key grass species under grazing in the Highland Sourveld of Natal
Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: C.R. Hurt --- Department of Grassland Science, Republic of South Africa M.B. Hardy --- , Republic of South Africa N.M. Tainton --- Department of Grassland Science, Republic of South AfricaRelative abundances of rangeland species have for many years been used to index trends in range condition following the impact of grazing. All species recorded in a botanical survey are usually classified according to their assumed reaction to grazing using... -
Impacts of mine dump pollution on plant species diversity, composition and structure of a semiarid savanna in Namibia
Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: I Mapaure --- Department of Biological Sciences, Namibia PM Chimwamurombe --- Department of Biological Sciences, Namibia BS Mapani --- Department of Geology, Namibia FA Kamona --- Department of Geology, NamibiaEffects of mine dump pollution on semiarid savanna vegetation were investigated in Kombat, Namibia. Vegetation structure, species richness, composition and diversity were compared between polluted and control sites. Concentrations of arsenic, chromium, copper, lead and zinc in soils were significantly... -
The quantification of rangeland condition in a semi-arid grassland of southern Africa
Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: H.C. van der Westhuizen W.L.J. van Rensburg H.A. SnymanThe degradation gradient technique was used to quantify rangeland, condition in areas ranging from poor, trampled areas close to watering points to well managed areas in a semi-arid, sweet grassland of southern Africa. Ecological values were linked to species by... -
Subclasses of Multivalent Functions Involving the Liu-Owa Operator
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: MohamedK. Aouf --- Faculty of Science, Egypt Teodor Bulboacă --- Faculty of Mathematics and Computer Science, RomaniaUsing the method of differential subordination, we investigate inclusion relationships among certain subclasses of analytic and p-valent functions, which are defined here by means of the Liu-Owa operator Qptp. -
The use of multivariate analysis as a tool to illustrate the influence of environmental variables on phytoplankton composition in the Vaal River, South Africa
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: Sanet Janse van Vuuren AJH PieterseThe highly eutrophic Vaal River system is subjected to algal blooms that cause problems ranging from aesthetically unacceptable conditions to the release of toxins. In order to understand how environmental variables influence one another and to determine the key environmental... -
Spatial variability of macrozoobenthic diversity on tidal flats of the Niger Delta, Nigeria: the role of substratum
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: N Zabbey --- Department of Animal Science and Fisheries, Nigeria AI Hart --- Department of Animal and Environmental Biology, NigeriaBaseline community assemblages and diversity of macrozoobenthic infauna in soft-bottomed intertidal flats at Bodo Creek on the upper reaches of the Andoni–Bonny estuarine system were determined spatially and in relation to sediment particle characteristics for two years from May 2006... -
Farmers’ choice of cattle marketing channels under transaction cost in rural South Africa: a multinomial logit model
Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: Jorine T Ndoro --- Agricultural Extension and Rural Resource Management Programme, South Africa Maxwell Mudhara --- African Centre for Food Security, South Africa Michael Chimonyo --- Department of Animal and Poultry Science, South AfricaThis study applied a transaction cost approach to the analysis of cattle marketing behaviour among smallholder farmers in communal land areas of KwaZulu-Natal, South Africa. The objective was to test the effects of information, negotiation, and monitoring costs on the... -
The creation of the SAVE consortium – Saving Asia’s Vultures from Extinction: a possible model for Africa?
Item type: Journal Article • Journal: Ostrich: Journal of African Ornithology • Authors: Christopher GR Bowden --- Globally Threatened Species Recovery Unit, Royal Society for the Protection of Birds, UKThere have been few faster, more dramatic and wide-scale species declines than those of South Asian vulture populations since the 1990s. This article describes the background to this problem, caused mainly by the veterinary drug diclofenac, and the establishment and... -
Managing dyspraxia: Pre-school teachers’ perceptions, experiences and strategies
Item type: Journal Article • Journal: Journal of Psychology in Africa • Authors: Athena Pedro --- Department of Psychology, South Africa Tessa Goldschmidt --- Department of Psychology, South AfricaDyspraxia is a childhood developmental disorder that manifests as a difficulty in thinking, planning, and executing planned movements or tasks. Dyspraxia affects approximately 5–6% of school-aged children. This study aimed to explore pre-school teachers’ awareness and understanding of dyspraxia, and... -
Evaluating the performance of South African primary care: a cross-sectional descriptive survey
Item type: Journal Article • Journal: South African Family Practice • Authors: Graham Bresick --- Division of Family Medicine, Klaus B von Pressentin --- Division of Family Medicine and Primary Care, Robert Mash --- Division of Family Medicine and Primary Care,Introduction: In 2018 governments reaffirmed their commitment to implementing primary health care (PHC) in the Astana Declaration. South Africa has introduced a number of health reforms to strengthen PHC and enable universal health coverage (UHC). UHC requires access to quality... -
The quality of feedback from outpatient departments at referral hospitals to the primary care providers in the Western Cape: a descriptive survey
Item type: Journal Article • Journal: South African Family Practice • Authors: Robert Mash --- Division of Family Medicine and Primary Care, South Africa Herma Steyn --- Department of Health, South Africa Muideen Bello --- Division of Family Medicine and Primary Care, South Africa Klaus von Pressentin --- Division of Family Medicine and Primary Care, South Africa Liezel Rossouw --- Department of Health, South Africa Gavin Hendricks --- Division of Family Medicine and Primary Care, South Africa Germarie Fouche --- Department of Health, South Africa Dusica Stapar --- Division of Family Medicine and Primary Care, South AfricaBackground: Coordinating care for patients is a key characteristic of effective primary care. Family physicians in the Western Cape formed a research network to enable them to perform practical research on key questions from clinical practice. The initial question selected... -
To honk or to hiss: uncovering call complexity in the Egyptian Goose Alopochen aegyptiaca
Item type: Journal Article • Journal: Ostrich: Journal of African Ornithology • Authors: Tess Gridley --- , South Africa Courtney EC Gardiner --- , South AfricaEgyptian Geese Alopochen aegyptiaca are distributed across most of Africa. Their calls dominate the soundscape of many urban areas, yet their acoustic behaviour is poorly documented or understood. Using acoustic recordings made across a range of behavioural contexts, groups sizes... -
How interfirm governance mechanisms and capabilities determine supply chain responsiveness in small businesses: Evidence from an African market
Item type: Journal Article • Journal: Africa Journal of Management • Authors: Dominic Essuman --- , Ghana David Asamoah --- , Ghana Emmanuel Kwabena Anin --- , GhanaThis paper examines whether supply chain capabilities (i.e., collaboration and coordination) mediate the relationships between interfirm governance mechanisms (i.e., formal control and social control) and supply chain responsiveness in the context of small businesses. Using survey data from 331 small... -
Correlation of variations in species abundance of Atlantic forests regenerating on abandoned pastures with different environmental and spatial variables
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: João Paulo de Maçaneiro --- , Brazil Laio Zimermann Oliveira --- , Brazil Lauri Amândio Schorn --- , Brazil Franklin Galvão --- , Brazil Guilherme Salgado Grittz --- , Brazil André Luís de Gasper --- , BrazilThe conversion of native forests into pastures is still a common practice in Brazil. Abandoned pastures have great potential for natural regeneration and therefore could play an important role in meeting the enormous demand for forest restoration. Few studies, however,... -
Argument estimates associated with meromorphic close-to-starlike and Bazilević functions
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Nak Eun Cho --- Pukyong National University, Republic of Korea Inhwa Kim --- Harris-Stowe State University, U.S.A H.M. Srivastava --- University of Victoria, CanadaThe object of the present paper is to derive some argument properties associated with meromorphic close-to-starlike and Bazilević functions in the punctured open unit disk. Furthermore, we investigate integral-preserving properties in a sector with some special cases of the main... -
Estimates for the Pre-Schwarzian norm for certain subclasses of analytic functions
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Rashid Ali --- Government College University Faisalabad, Pakistan Mohsan Raza --- Government College University Faisalabad, PakistanFor λ ≥ 1, let be the class of analytic functions f in the open unit disc defined by . Similarly, for the class is defined by . In this article, we present estimates for the pre-Schwarzian norm of functions...