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Simulating future rangeland production in central South Africa
No full textEnglish: A large part (69%) of South Africa’s surface is suitable for grazing resulting in livestock farming being the largest agricultural sector in the country. Rangelands are an important resource for a stock farmer as it provides a cheap food source for the livestock midst it is in a good condition. In order to feed an ever-increasing population, better rangeland management practices are needed to ensure food security. Adaptation strategies should address climate variability and change, which is already suspected to be the main cause for variable crop yields and rangeland production. It is therefore imperative to investigate what the effect of climate change will be on rangeland production in the long run. Thus, the main aim of this study was to assess the historical and future rangeland production in the Bloemfontein area of South Africa, which falls within the dry Themeda-Cymbopogon veld type and is deemed representative of the central grassland biome.
Observed climate data was sourced from the South African Weather Service (SAWS) station at Bloemfontein Airport for the historical base period (1980/81 – 2009/10). Simulated climate data was also obtained for the base and three future periods (i.e. current period (2010/11 – 2039/40), near future (2040/41 – 2069/70) and distant future (2070/71 – 2098/99)) from five Global Climate Models (GCMs) using two Representative Concentration Pathways (RCPs). Here RCP 4.5 and 8.5 respectively represented intermediate and high greenhouse gas emission pathways. Measured rangeland production data was obtained from the Sydenham Experimental Farm outside Bloemfontein for the historical base period. PUTU VELD (PV) was used to simulate rangeland production for the base and future time periods. Inputs included rainfall (mm), minimum and maximum temperature (°C), sunshine hours (h) and evapotranspiration (mm.d-1) at daily intervals, where the latter was estimated using the Hargreaves-Samani method. PV outputs included maximum dry matter production (DMPmax), the date of occurrence of DMPmax (Dtp) and the number of moisture stress days (MSD).
Results showed a weak positive trend in measured DMPmax over the historical base period. It should be stressed that the results of this study should not be interpreted or extrapolated outside the context of this document since the validation of PV over the historical base period yielded poor results (R2 = 0.28), revealing possible serious
overfitting issues. PV was also found to generally underestimate DMPmax when using GCM data as input when compared to runs employing SAWS data. Dtp showed a weak negative trend, implying a tendency for Dtp to occur slightly earlier in the season with time, while MSD revealed weak linear trends over the base period. Using 3-month running means of the Niño 3.4 anomalies as predictor of standardized DMPmax showed real promise as approximately 17.5% of the variation in DMPmax could be explained by the variation in the July-August-September (JAS) Niño 3.4.
With respect to the future periods, the results showed that on average DMPmax will decrease slightly over time under RCP 4.5, while it will increase under RCP 8.5. In terms of grazing capacity, both RCPs revealed that more land will be needed per animal for sustainable farming. The Dtp showed a general shift to later in the growing season under both RCPs. It was also noted that although both RCPs had more MSDs when compared to the base period, there were larger differences observed under RCP 8.5.
It was suggested that active monitoring and good rangeland improvement techniques be utilised by livestock farmers to ensure a good rangeland condition with adequate food supply for livestock. Future work should focus on evaluating other rangeland production models for this region.Afrikaans: ʼn Groot deel (69%) van Suid-Afrika se oppervlakte is geskik vir weiding, met die gevolg dat veeboerdery die grootste landbousektor in die land is. Weiveld is ʼn belangrike hulpbron vir ʼn veeboer aangesien dit ʼn goedkoop voedselbron vir vee kan wees mits dit in ʼn goeie toestand is. Om aan die toenemende bevolking voedsel te verskaf, word beter veldbestuurspraktyke benodig om voedselsekerheid te waarborg. Aanpassingstrategieë behoort klimaatveranderlikheid en -verandering aan te spreek, wat reeds aangevoer word as die hoofoorsaak vir veranderlike gewasopbrengste en weidingproduksie. Dit is dus noodsaaklik om ondersoek in te stel na die langtermyn uitwerking van klimaatsverandering op weidingproduksie. Die hoofdoel van hierdie studie was dus om die historiese en toekomstige veldproduksie in die Bloemfontein-gebied van Suid-Afrika, wat binne die droë Themeda-Cymbopogon-veldtipe val en as verteenwoordigend van die sentrale graslandbioom beskou word, te evalueer.
Waargenome klimaatdata was verkry vanaf die Suid-Afrikaanse Weerdiens (SAWS) se stasie op Bloemfontein Lughawe vir die historiese basistydperk (1980/81 – 2009/10). Gesimuleerde klimaatdata is ook verkry vir die basis en drie toekomstige tydperke (d.w.s. huidige tydperk (2010/11 – 2039/40), nabye toekoms (2040/41 – 2069/70), en verre toekoms (2070/71 – 2098/99)) vanaf vyf globale klimaatmodelle (GKM’e) deur gebruik te maak van twee verteenwoordigende konsentrasiepaaie (VKP’s). Hier verteenwoordig VKP 4.5 en 8.5 onderskeidelik intermediêre en hoë kweekhuisgasvrystellings. Gemete weidingproduksiedata is verkry van die Sydenham Proefplaas buite Bloemfontein vir die historiese basistydperk. PUTU VELD (PV) is gebruik om weidingproduksie te simuleer vir die basis en toekomstige tydperke. Insette sluit in reënval (mm), minimum en maksimum temperatuur (°C), sonskynure (h) en evapotranspirasie (mm.d-1), waar laasgenoemde volgens die Hargreaves-Semani-metode geraam is. PV uitsette sluit in maksimum droëmateriaalproduksie (DMPmax), die datum van die voorkoms van DMPmax (Dtp) en die aantal vogstremmingsdae (VSD).
Resultate het ʼn swak positiewe tendens in gemete DMPmax oor die historiese basistydperk getoon. Dit moet egter beklemtoon word dat die resultate van hierdie studie nie buite die konteks van hierdie dokument geïnterpreteer en geëkstrapoleer moet word nie, aangesien die validering van PV oor die historiese basistydperk swak
resultate opgelewer het (R2 = 0.28), wat moontlike ernstige oorpassingsprobleme toon. Daar was ook gevind dat PV oor die algemeen DMPmax onderskat wanneer GKM-data as insette gebruik word in vergelyking met lopies wat SAWS-data gebruik. Dtp het ʼn swak negatiewe neiging getoon, wat daarop dui dat Dtp mettertyd effens vroeër in die seisoen plaasvind, terwyl VSD ʼn swak lineêre tendens oor die basistydperk getoon het. Die gebruik van 3-maand lopende gemiddelde van die Niño 3.4-anomalieë as voorspeller van gestandaardiseerde DMPmax het werklike belofte getoon, aangesien ongeveer 17.5% van die variasie in DMPmax verklaar kon word deur die variasie in die Julie-Augustus-September (JAS) Niño 3.4
Met betrekking tot die toekomstige tydperke het die resultate getoon dat DMPmax oor die algemeen mettertyd sal afneem onder VKP 4.5, terwyl dit onder VKP 8.5 sal toeneem. Wat weidingskapasiteit betref, het beide VKPs getoon dat meer grond per dier benodig word vir volhoubare boerdery. Die Dtp het ʼn algemene verskuiwing tot later in die groeiseisoen onder beide VKPs getoon. Daar is ook opgemerk dat hoewel beide VKPs meer VSDs gehad het in vergelyking met die basistydperk, was daar groter verskille waargeneem onder VKP 8.5.
Daar is voorgestel dat aktiewe monitering en goeie veldverbeteringstegnieke deur veeboere aangewend moet word om ʼn goeie veldtoestand te verseker met voldoende voedselvoorsiening vir vee. Toekomstige werk moet fokus op die evaluering van ander weidingproduksiemodelle vir hierdie streek.Agricultural Research CouncilInkaba ye Afric
South Africa's social contract: the Economic Freedom Fighters and the rise of a new constituent power?
No full textTaking the South African constitution as an eminent symbol of the South African social contract, and noting
the opinion of many that the contract has failed to deliver, this article explores the concept of the social
contract in South Africa by examining two contentions. The first, that the South African social contract, or
constitution, was not entirely inclusive to begin with. And the second, that the radical opposition party –
the Economic Freedom Fighters (EFF) – represents the rise of a new constituent power from the unemployed and disenfranchised populous: those seen to have been left out of the social contract. Within this article, I follow Negri’s work on constituent power, broadly taking the term to denote “the power of the people”. Through exploring these contentions, this article comes to an impasse: that South Africa’s social contract was, and continues to be, conditioned in advanced by the preceding administration or constituted power, which limits, too, the possibilities of a new constituent power represented by the EFF.Publisher's versio
DE BEER, J. Inventory of documents
No full textCOVERAGE 1940-1944; 1 File; 0.11 metrePrivate papers of J. De Beer, Deputy Director of Hospital Services Orange Free State
NATIONAL PARTY NATAL Inventory of documents
No full textCOVERAGE 1913-1976; 584 File; 17,33 Metres.
AUDIO CASSETTES IN ARCA COLLECTION = 11Papers of the National Party Natal, founded on June 15, 1915 at Dundee
SA INSTITUTE FOR RACE RELATIONS Survey
No full textCOVERAGE: 0.35 metres; 1965-1978A survey of race relations in S
A construction project management knowledge model: the type and level of knowledge required
No full textEnglish: Construction project managers come from diverse backgrounds and may, therefore, lack the knowledge set currently required in order to be competent and effective in practice. The aim of this article is to establish the National Qualifications Framework (NQF) level of each type of knowledge area required for a competent and effective construction project manager in South Africa. These levels of knowledge are important, in order to develop a proposed construction project management knowledge model to be used by the construction industry. A mixed methods research design was used, including structured questionnaires (n = 40), interviews (n = 10), and a single case study. The questionnaire survey, using closeended questions measured on a 5-point Likert scale, tests the importance of and rated the NQF qualification levels of each knowledge type fit for
project managers in the built environment. The rating assisted in knowing to what knowledge depth project managers need to be educated and trained. Interviews were conducted with 10 construction professionals to obtain their views on the importance of industry-specific know ledge of a construction project manager and to critically review the form of knowledge considered essential. The case study of a building project to the value of R35 million was used to gain understanding of the impact that industry-specific knowledge, or the lack thereof, may have on the successful completion of a project. Results showed that qualifications to gain industry-specific knowledge should at least be on NQF level 6; a qualification on NQF level 7 is recommended to gain adequate project manage ment knowledge (theory). These findings are important, as some construction project management courses in South Africa are currently below NQF level 6. This may be contributing to industry not producing construction project managers with the required knowledge set. The proposed model outlines the adequate knowledge sets and level
thereof that can be used when designing training and educational degrees for construction project managers. The proposed model could also be used in practice as a guideline for placing or promoting construction project managers.Afrikaans: Konstruksieprojekbestuurders kom van uiteenlopende agtergronde, en mag dus
die kennisstel kort wat tans benodig word om vaardig en effektief in die praktyk te wees. Die doel van hierdie artikel is om die Nasionale Kwalifikasieraamwerk (NKR)-vlak van elke tipe kennisarea vas te stel wat benodig word vir ’n bevoegde en effektiewe bouprojekbestuurder in Suid-Afrika. Hierdie vlakke van kennis is belangrik om ’n voorgestelde konstruksieprojekbestuur-kennismodel te ontwikkel wat deur die konstruksiebedryf gebruik kan word. ’n Gemengde metodes navorsingsontwerp is gebruik, insluitend gestruktureerde vraelyste (n = 40), onderhoude (n = 10) en ’n enkele gevallestudie. Die vraelys-opname deur middel van geslote vrae het die belangrikheid van en gegradeerde NKR-vlakke van elke kennissoort geskik vir projekbestuurders in die beboude omgewing, gemeet op ’n 5-punt Likert-skaal. Die gradering het gehelp om te weet tot watter kennisdiepte projekbestuurders opgelei moet word. Onderhoude is gevoer met 10 konstruksiewerknemers om hul standpunte oor die belangrikheid van bedryfspesifieke kennis van ’n konstruksieprojekbestuurder te verkry en om die vorm van kennis wat noodsaaklik beskou word, krities te hersien. Die gevallestudie van ’n bouprojek ten bedrae van R35 miljoen is gebruik om begrip te kry van die impak wat bedryfspesifieke kennis, of die gebrek daarvan, op die sukses van ’n projek kan hê. Resultate het getoon dat kwalifikasies om bedryfskennis te verkry, ten minste op NKR-vlak 6 moet wees; ’n kwalifikasie op NKR-vlak 7 word aanbeveel om voldoende projekbestuurskennis (teorie) te verkry. Hierdie bevindings is belangrik aangesien sommige konstruksieprojekbestuurskursusse in Suid-Afrika tans laer as NKR-vlak 6 is. Dit kan bydra daartoe dat die industrie tans konstruksieprojekbestuurders sonder die vereiste kennisstel in diens neem. Die voorgestelde model beskryf die toereikende kennisstelle en vlak
daarvan wat gebruik kan word by die ontwerp van opleidingskwalifikasies vir konstruksieprojekbestuurders. Die voorgestelde model kan ook in die praktyk gebruik word as riglyn om konstruksieprojekbestuurders te plaas of te bevorder.Publisher's versio
DE WET, Jacobus Ignatius Inventory of documents
No full textPrivate papers of J.I.de Wet, Senator [1955-1960].COVERAGE 1957; 6 Files; 0,33 metres
FOURIE, FMM Inventory of documents
No full textMinute book of the NP. Filed with PV21 NP OFS FIles II28 and II2
Household food gardens as HIV and AIDS impact mitigation response in poor urban communities in Southern Africa: an economic analysis
No full textHIV and AIDS impact mitigation remains a high priority for countries around the world, especially for Southern African countries where HIV and AIDS prevalence rates are high. In this region, there is increasing recognition of the need to promote interventions which mitigate the adverse effects of HIV and AIDS. Consequently, household food gardens have attracted considerable attention as an intervention strategy that can help to mitigate the impacts of HIV and AIDS. This thesis aims to examine the role of household food gardens in mitigating the impact of HIV and AIDS in poor urban communities in Lesotho, South Africa and Zimbabwe. The study employs data from a longitudinal quasi-experimental study using both quantitative and qualitative data collection methods. Basic descriptive and advanced econometric methods are employed to analyse the data in view of the various study objectives. First, the results show that within the informal urban food system, household food gardens are an important component of the food supply system. Second, the results also show how the sale, remittance and bartering of surplus garden produce enhance the availability of and access to food. The final result shows that household food gardens have a positive and significant impact on household food security, both for food gardens in general and for programme gardens. The study recommends that household food garden programmes be scaled-up, not only in the context of HIV and AIDS impact mitigation strategies, but in relation to development policies in general.HEARDSAD