Thesis (DPhil (Geography and Environmental Studies))--University of Stellenbosch, 2009. / ENGLISH ABSTRACT: The rapid growth of tourism, particularly heritage tourism, in South Africa is leading to a detrimental impact on heritage resources. Part of the problem lies in the lack of knowledge visitors have of the significance and vulnerability of the resources they are engaging with. Another part of the problem is the inherent conflict between the heritage tourism sector and the heritage management sector. Whilst sharing the same resource base, each sector has very different aims. Tourism seeks to exploit heritage resources, whilst heritage management seeks to conserve them. These problems are not necessarily restricted to South Africa and the study of its nature and extent is here limited to the Little Karoo. The Little Karoo is defined in this dissertation as the area in the Western Cape bounded by the Langeberg and Outeniqua Mountains in the south, and the Swartberg in the north. It includes the towns of Montagu, Barrydale, Ladismith, Amalienstein, Zoar, Calitzdorp, Van Wyksdorp, Oudtshoorn, Dysselsdorp, De Rust and Herold. Of importance to this research is the fact that the Little Karoo can be accessed by a variety of passes, poorts and kloofs. This study has been undertaken in order to explore a non-empirical solution to the problem of the human impact on heritage resources through their thematic interpretation and presentation. This research also aims to improve the relationship between the tourism and heritage industries by introducing a shared terminology in the form of a model or framework. This framework is a way of organising and presenting the heritage story in such a way that both heritage tourism and heritage managers (and other stakeholders) can understand. The aim of the study is to devise a mechanism with which to identify, organise, interpret and present heritage resources in a thematic manner. The resulting thematic framework will hopefully enrich the heritage experience of visitors to heritage sites while providing guidance as to the vulnerability of heritage resources. A secondary objective is to develop common terminology for the heritage tourism and heritage management communities. The intent is to improve the relationship between these two sectors and thereby mitigate further damage to heritage resources. Data for this study was collected from several empirical sources. Extant and primary data was accessed. Extant data came from the pertinent published sources, while primary data was collected via a combination of personal and group face-to-face semi-structured interviews and personal observation of heritage sites in the Little Karoo during 2003 and 2004. The main outcome of this research was the development of a South African Heritage Tourism Thematic Framework (SAHTTF). The SAHTTF is, in part, based on and inspired by frameworks from the United States, Australia, Canada and South Africa. There are three tiers within the framework: theme groups, themes and sub-themes. The framework is intended to be flexible and the three tiers can be mixed and matched in whatever way best serves the story of the heritage resource in question. The five theme groups are: Development of the environment; Peopling our land; Way of life; Governing South Africa and Developing South Africa. The whole story of South Africa can be organised and presented using this framework. However, in order to keep this study within reasonable limits, the focus of the story was limited to the heritage story of the Little Karoo. The case studies of the Cango Caves, Cogmans Kloof, Swartberg Pass and Seweweeks Poort tested the effectiveness of the SAHTTF. It is recommended that the SAHTTF be presented to the heritage tourism and heritage management sectors for further evaluation and testing. This research has proved that the SAHTTF can be an effective tool in the identification, organization, interpretation and presentation of heritage resources. / AFRIKAANSE OPSOMMING: Die snelle groei van toerisme, veral erfnistoerisme, in Suid-Afrika het tot gevolg dat erfnisbronne onder groot druk geplaas word. Die probleem is deels dat besoekers geen of weinig kennis dra van die kwesbaarheid en belangrikheid van die bronne waarmee hulle handel. Verder is die probleem die belangebotsing tussen erfnistoerisme en erfnisbestuur sektore. Toerisme verbruik erfnisbronne, terwyl erfnisbestuur poog om dit te bewaar. Hierdie probleem is egter nie noodwendig eie aan Suid-Afrika nie en vir die doeleindes van dié studie word die omvang en aard daarvan slegs in die Klein Karoo ondersoek. Die Klein Karoo word beskou as die gebied in die Westelike Provinsie wat in die suide deur die Langeberge en Outenikwaberge en in die noorde deur die Swartberge begrens word. Dit omsluit die dorpe Montagu, Barrydale, Ladismith, Amalienstein, Zoar, Calitzdorp, Vanwyksdorp, Oudtshoorn, Dysselsdorp, De Rust en Herold. Die Klein Karoo kan deur talle passe, poorte en klowe bereik word – die belangrike feit wat in hierdie studie ontgin word. Die navorsing is onderneem ten einde 'n nie-empiriese oplossing vir die impak van die mens op erfnisbronne deur tematiese interpretasie en voorstelling te vind. Dit beoog om die verhouding tussen die bedryf van erfnistoerisme en erfnisbestuur te bestendig deur gedeelde terminologie in die vorm van 'n model of raamwerk. Hierdie raamwerk bied 'n metode om die verhale van erfnis so aan te bied dat beide die bedrywers van erfnistoerisme en -bestuur begrip daarvoor kan ontwikkel. Die doel van die navorsing is om 'n meganisme te vind waardeur die erfnisbronne op 'n tematiese wyse geïdentifiseer, georganiseer, vertolk en aangebied kan word. Hierdie tematiese raamwerk sal hopelik besoekers se ervaring van erfnisbronne verryk en leiding gee rakende die kwesbaarheid van terreine. Data vir die navorsing is uit verskeie empiriese bronne versamel. Bestaande en primêre data is gebruik. Bestaande data was afkomstig van toepaslike publikasies en primêre data is versamel en ingewin via 'n kombinasie van individuele en groepsonderhoude deur middel van semigestruktureerde onderhoude, asook persoonlike waarneming van verskillende erfnisterrreine in die Klein Karoo tussen 2003 en 2004. Die belangrikste opbrengs uit die navorsing is die ontwikkeling van 'n Suid-Afrikanse Erfnistoerisme Tematiese Raamwerk (South Afican Heritage Tourism Thematic Framework – SAHTTF). Die SAHTTF is deels gebaseer op, en geïnspireer deur, soortgelyke raamwerke in die VSA, Australië, Kanada en Suid-Afrika. Daar is drie vlakke in die raamwerk: tematiese groepe, temas en sub-temas. Die raamwerk is aanpasbaar en die drie vlakke kan in enige kombinasie gebruik word om die verhaal of geskiedenis van die betrokke bron ten beste voor te stel. Die vyf tematiese groepe is: Onwikkeling van die omgewing; Bevolking van ons land; Lewenswyses; Regering van Suid-Afrika; en Ontwikkeling van Suid-Afrika. Die hele erfnisverhaal van Suid-Afrika kan georganiseer en voorgestel word deur dié raamwerk. Ten einde hierdie navorsing hanteerbaar te hou, is op die erfnisverhaal van die Klein Karoo gekonsentreer. As gevallestudies het die Kangogrotte, Kogmanskloof, Swartbergpas en Seweweekspoort as toets vir die doeltreffendheid van die raamwerk gedien. Die navorsing beveel aan dat die SAHTTF aan die beheerstrukture van erfnistoerisme en erfnisbestuur voorgelê word vir verdere evaluering en toetsing. Die navorsing het bevind dat die SAHTTF 'n doeltreffende instrument kan wees in die identifisering, organisering, vertolking en voorstelling van ons erfnis bronne.

The Karretjie People, or Cart People are a peripatetic community and are descendants of the KhoeKhoen and San, the earliest inhabitants of the Karoo region in South Africa. As a landless and disempowered community they are dependent upon others for food and other basic necessities specifically, and other resources generally. Compared to children in South Africa generally, the Karretjie children are in every sense of the most severely deprived. Their fathers are by and large sheep-shearers, often their only specialised skill, and which is primarily required only on demand and on an irregular and/or seasonal basis. The children’s mothers as keepers of the karretjie (cart) overnight shack, with other adult caretakers, are without predictable income for most of the year. The service that the adult men deliver to the farming community necessitates continuous spatial mobility and is made possible by a cart and donkeys, which also enable them to adapt to changing circumstances. High levels of spatial mobility as well as economic demands on individual domestic units result in inventive utilisation of scarce resources and entails, amongst others, in children oscillating between different karretjie (cart) units.

The Karretjie People, or Cart People are a peripatetic community and are descendants of the KhoeKhoen and San, the earliest inhabitants of the Karoo region in South Africa. As a landless and disempowered community they are dependent upon others for food and other basic necessities specifically, and other resources generally. Compared to children in South Africa generally, the Karretjie children are in every sense of the most severely deprived. Their fathers are by and large sheep-shearers, often their only specialised skill, and which is primarily required only on demand and on an irregular and/or seasonal basis. The children’s mothers as keepers of the karretjie (cart) overnight shack, with other adult caretakers, are without predictable income for most of the year. The service that the adult men deliver to the farming community necessitates continuous spatial mobility and is made possible by a cart and donkeys, which also enable them to adapt to changing circumstances. High levels of spatial mobility as well as economic demands on individual domestic units result in inventive utilisation of scarce resources and entails, amongst others, in children oscillating between different karretjie (cart) units.

The re-introduction of large carnivores into relatively small conservation areas that fall within the historic distribution range of the species is becoming an increasingly common occurrence. The success of such re-introductions depends very much on the quality of the information that is available to guide management decisions, but in many cases, little information is available. The re-introduction of lions and cheetahs to Sanbona created the opportunity to monitor the behaviour of re-introduced predators to a relatively large system that was characterised by a low ungulate stocking density and little standing water. The broad aims were to study the feeding and spatial ecologies of the lions and cheetahs, to collect standard base-line data, and to examine the effects of the low prey density and limited standing water on habitat selection, range size and diet. The diet (data collected from direct observation and faecal analysis) was similar to that reported in previous studies, and lions and cheetahs preferred greater kudu, black wildebeest and springbok. Lions preferred medium to large prey items, and cheetahs preferred medium to small prey items. The hilly and mountainous terrain of much of the reserve meant that only 50% of the total space was available to the predators. Home ranges of most of the predators were focused around the single large body of standing water. This is likely to have been a response to the water, the vegetation, and the prey that was attracted to these. Habitat selection was also influenced by inter and intra-specific interactions at least for a solitary male lion and female cheetahs. Range sizes were larger than on some other reserves and it is suggested that this was a result of the low prey density. These results form the basis for management recommendations including the importance of continuing to monitor the system and opening up additional parts of the reserve to the predators.

Thesis (MSc)--Stellenbosch University, 2012. / ENGLISH ABSTRACT: Basin subsidence analysis, employing the backstripping method, indicates that fundamentally two different basin-generating mechanisms controlled Tanqua depocentre development in SW Karoo Basin. The subsidence curves display initial dominantly decelerating subsidence, suggesting an extensional and thermal control possibly in a strikeslip setting during the depocentre formation; on the other hand, subsequent accelerating subsidence with time suggests that the dominant control on the depocentre formation in SW Karoo was flexure of the lithosphere. Based on these observations on the subsidence curves, it is possible to infer that the first stage of positive inflexion (~ 290 Ma) is therefore recognised as the first stage of Tanqua depocentre formation. Petrographic study show that most of the studied sandstones of the Tanqua depocentre at depth of ~ 7.5 Km were subjected to high pressure due to the overlying sediments. They are tightly-packed as a result of grains adjustment made under such pressure which led also to the development of sutured contacts. It is clear the high compaction i.e. grain deformation and pressure solution occurred on the sediments; leading to total intergranular porosity reduction of the quartz-rich sediments and dissolution of the mineral grains at intergranular contacts under non-hydrostatic stress and subsequent re-precipitation in pore spaces. Furthermore, siliciclastic cover in the Tanqua depocentre expanded from minimal values in the early Triassic (Early to Late Anisian) and to a maximum in the middle Permian (Wordian -Roadian); thereby accompanying a global falling trend in eustatic sea-level and favoured by a compressional phase involving a regional shortening due to orogenic thrusting and positive inflexions (denoting foreland basin formation). The estimate of sediment volume obtained in this study for the Permian Period to a maximum in the middle Permian is therefore consistent with published eustatic sea-level and stress regime data. In addition, this new data are consistent with a diachronous cessation of marine incursion and closure of Tanqua depocentre, related to a compressional stress regime in Gondwana interior during the late Palaeozoic. / AFRIKAANSE OPSOMMING: Die ontleding van komversakking met behulp van die terugstropingsmetode bring aan die lig dat die ontwikkeling van die Tankwa-afsettingsentrum in die Suidwes-Karoo-kom hoofsaaklik deur twee verskillende komvormende meganismes bepaal is. Die versakkingskurwes toon aanvanklike, hoofsaaklik verlangsaamde versakking, wat daarop dui dat ekstensie- en termiese beheer gedurende die vorming van die afsettingsentrum plaasgevind het, waarskynlik in strekkingwaartse opset. Aan die ander kant toon daaropvolgende versnellende versakking wat mettertyd plaasgevind het dat die vorming van die afsettingsentrum in die Suidwes-Karoo eerder oorwegend deur kromming van die litosfeer beheer is. Op grond van hierdie waarnemings met betrekking tot die versakkingskurwes, kan mens aflei dat die eerste stadium van positiewe infleksie (~ 290 Ma) dus as die eerste stadium van die vorming van die Tankwa-afsettingsentrum beskou kan word. Petrografiese studie toon dat die meeste van die sandsteen wat van die Tankwaafsettingsentrum bestudeer is, op diepte van ~ 7,5 Km aan hoë druk onderwerp was weens die oorliggende sedimente. Die sandsteen is dig opmekaar as gevolg van die korrelaanpassing wat onder sulke hoë druk plaasvind, wat op sy beurt ook tot die ontwikkeling van kartelnaatkontakte aanleiding gegee het. Dit is duidelik dat die sediment aan hoë verdigting, dit wil sê korrelvervorming en drukoplossing, onderwerp was, wat gelei het tot algehele afname in interkorrelporeusheid by die kwartsryke sedimente; die ontbinding van die mineraalkorrels in interkorrelkontaksones onder niehidrostatiese spanning, en daaropvolgende herpresipitasie in poreuse ruimtes. Voorts het silisiklastiese dekking in die Tankwa-afsettingsentrum toegeneem van minimale waardes in die vroeë Triassiese tydperk (vroeë tot laat Anisiaanse tydperk) tot hoogtepunt in die mid-Permiaanse tydperk (Wordiaans–Roadiaans). Dié ontwikkeling het gepaardgegaan met algemene dalingstendens in die eustatiese seevlak, en is verder aangehelp deur saamdrukkingsfase wat gekenmerk is deur regionale verkorting weens orogeniese druk en positiewe infleksies (wat met voorlandkomvorming saamhang). Die geraamde sedimentvolume wat in hierdie studie vir die Permiaanse tydperk bepaal is, met die hoogtepunt in die middel van dié tydperk, is dus in pas met gepubliseerde data oor die eustatiese seevlak en spanningstoestand. Daarbenewens strook hierdie nuwe data met diachroniese staking van mariene instroming en die afsluiting van die Tankwaafsettingsentrum wat met spanningstoestand in die Gondwana-binneland gedurende die laat Paleosoïkum verband hou.

A grazing trial investigating the effect of season of grazing and stocking rate initiated at the Nortier Experimental Farm in 1988 provided an opportunity to assess the response of the veld to both grazing and environmental influences in an arid environment. The trial allowed an assessment of the relative influence of internal (equilibrium) and external (non-equilibrium) forces on the dynamics of an arid rangeland. This study involved the analysis of a nine year data set stretching from 1988 to 1996 and served to provide evidence supporting the existence of an equilibrium/non-equilibrium continuum in rangeland dynamics. The most significant implication of this result is that rangeland systems should not be classified as either equilibrial or non-equilibrial, but rather according to a continuum extending between equilibrium and non-equilibrium poles. The exact position of any system on this continuum is a function of the relative influence of internal and external forces on its species dynamics. The dynamics of the veld at the Nortier Experimental Farm showed significant response to both grazing and environmental variables suggesting conformity to both equilibrial and non-equilibrial paradigms. Both ordination and analysis of variance highlighted the importance of rainfall particularly in the fluctuations of the predominant grass species, Ehrharta calycina, which increased in abundance with rainfall. Partial ordination enabled the assessment of species variation following the removal of variation associated with rainfalL Partial ordinations revealed the gradual, directional movement of samples through multivariate space in response to grazing treatments. Individual plant species were also shown to be responding to grazing, the extent of which was influenced by season of grazing and stocking rate. Both the partial ordinations and the ANOVA showed Melothria sp., Tetragonia fruiticosa and Hermannia scordifolia as increasing and Ruschia caroli as decreasing in absolute abundance in response to grazing. Season of grazing was shown to significantly influence the abundance of H. scordifolia over time. The 'shrublherb complex', which constitutes the 'key resource' at the Nortier Experimental Farm displayed an increase in absolute abundance over the duration of the trial. This increase in absolute abundance was accompanied by an increase in the relative abundance of the palatable component of this resource. The application of medium to heavy stocking rates during spring, summer and autumn and low stocking rates during winter resulted in elevated absolute abundances of palatable plants. Furthermore, low stocking rates, when averaged across all season of grazing treatments, resulted in a significantly higher absolute abundance of unpalatable plants. These findings provide the basis for the development of management principles for the Strandveld Vegetation Type. The application of medium to heavy stocking rates within a rotational grazing system, as recommended by the literature dealing with grazing systems in the Karoo, is supported by the results of the Nortier grazing trial. Medium to heavy stocking rates should be applied during spring, summer and autumn and low stocking rates during the winter months. Furthermore, it is recommended that rests of between 12 and 14 months should be afforded to portions of the veld periodically due to the variability in growth, flowering and fruiting times ofdifferent plants in the Karoo. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2005.

Thesis (PhD)--University of Stellenbosch, 2004. / ENGLISH ABSTRACT: Foreland basins commonly fill with sediment derived from the adjacent fold/thrust belt, providing a relatively simple source-to-basin configuration. However, that is not true for the early southwestern Karoo Basin, since the composition of the Ecca Group sedimentary rocks do not match the composition of the adjacent fold/thrust belt. The southwestern Karoo Basin is bordered to the west and south by the Cape Fold Belt (CFB) and provides the opportunity to study the linkage between its early structural evolution and deposition in the two spatially and temporally distinct Tanqua and Laingsburg depocentres. The CFB was formed when the early Palaeozoic passive continental margin, which formed a large section of the southern edge of Gondwana, evolved into an active convergent margin during the late Palaeozoic. Orogenesis resulted in a northwest-trending Cedarberg branch and an eastwest-trending Swartberg branch. The oroclinal bend between the two branches includes large-scale northeast-trending syntaxis structures, such as the Hex River and Baviaanshoek anticlinoria, which influenced the sedimentation path into the basin. Spectral gamma ray (SGR), mineralogical and geochemical studies of exposed rocks from the Tanqua and Laingsburg depocentres indicate a near uniform provenance for both, dominated by granitic and metamorphic material derived from a provenance seemingly far beyond the CFB. SGR data, combined with lithology, show that regional stratigraphic correlation is possible in the Skoorsteenberg, Kookfontein and Waterford Formations in the Tanqua depocentre. The same is true for the Laingsburg and Fort Brown Formations in the Laingsburg depocentre. There are no major changes in the SGR data set between the successive sandstone or shale units that could imply different origin, and no distinct signals in the SGR pattern of the shale intervals that could potentially correspond to maximum flooding surfaces. The Tanqua and Laingsburg depocentre sandstones are very fine- to lower mediumgrained, tightly packed, poorly to well sorted, and have undergone mechanical compaction and pressure solution. The mineralogical composition and texture of these sandstones suggest that they have undergone high-grade diagenesis to low-grade regional burial metamorphism to the lower greenschist facies (250 ± 50ºC; ~2 kbars). They are mineralogically and geochemically classified as lithic arenites and greywackes, and the Tanqua depocentre sandstones are slightly more mature than the Laingsburg depocentresandstones. REE patterns for the Tanqua and Laingsburg depocentre sandstones are similar, suggesting that both form part of the same evolutionary pattern and that the sediments have one common origin, i.e. a provenance predominantly composed of granitic material. Homogenous εNd-values for all sandstone samples of around –5 at the time of deposition indicate that there is little or no variation in provenance between the Tanqua and Laingsburg depocentre sediments. TCHUR model ages of 0.70 to 0.95 Ga, and TDM model ages of 1.19 to 1.49 Ga, resulted from a mixture of Archaean and Proterozoic material in unknown proportions. The most likely source terrane is thought to be the North Patagonian Massif. The latter show Nd isotopic compositions corresponding to an average εNd-value of -5 at 265 Ma. / AFRIKAANSE OPSOMMING: Voorlandkomme word oor die algemeen gevul met sediment afkomstig van die aanliggende plooigordel, wat lei tot ‘n redelik eenvoudige brongebied-tot-afsettingskom konfigurasie. Dit is egter nie van toepassing vir die vroeë suidwestelike Karookom nie, aangesien die samestelling van die Ecca Groep sedimentêre gesteentes nie ooreenstem met die samestelling van die aanliggende plooigordel nie. Die suidwestelike Karookom word aan die weste en suide begrens deur die Kaapse Plooigordel en bied die geleentheid om die verwantskap tussen die vroeë strukturele evolusie en afsetting in die twee ruimtelik en temporeel afsonderlike Tankwa en Laingsburg subkomme te bestudeer. Die Kaapse Plooigordel het gevorm toe die vroeë Palaeosoïkum kontinentale grens, wat ‘n groot deel van die suidelike grens van Gondwana was, ontwikkel het tot ‘n aktiewe konvergerende grens gedurende die laat Palaeosoïkum. Orogenese het gelei tot die vorming van ‘n noordwes-strekkende Sederberg tak en ‘n ooswes-strekkende Swartberg tak. Die oroklinale buig tussen die twee takke sluit grootskaalse noordoosstrekkende sintaksis strukture in, soos die Hex Rivier en Baviaanshoek antiklinoria, wat die sedimentasie rigtings na die kom beïnvloed het. Spektrale gammastraal (SGR), mineralogiese en geochemiese studies op die dagsome van die Tankwa en Laingsburg subkomme dui ‘n byna identiese brongebied aan vir beide, oorheers deur granitiese en metamorfe materiaal vanaf ‘n brongebied oënskynlik vêr vanaf die Kaapse Plooigordel. SGR data, gekombineer met litologie, dui aan dat dit moontlik is om regionale stratigrafiese korrelasies in the Skoorsteenberg, Kookfontein en Waterford Formasies in die Tankwa subkom te maak. Dieselfde geld vir die Laingsburg en Fort Brown Formasies in die Laingsburg subkom. Daar is geen groot veranderinge, wat ‘n verskil in oorsprong kan aandui, in the SGR datastel tussen die opeenvolgende sandsteen of skalie eenhede nie, en ook geenuitstaande tekens in the SGR patroon van die skalie-intervalle wat moontlik kan ooreenstem met ‘n maksimum vloedingsvlak nie. Die Tankwa en Laingsburg subkom sandsteenlae is baie fyn- tot laervlak mediumkorrelrig, dig gekompakteer, swak tot goed gesorteer, en het meganiese kompaksie en drukoplossing ondergaan. Die mineralogiese samestelling en tekstuur van hierdie sandsteenlae dui daarop dat hulle hoë-graadse diagenese tot lae-graadse regionale begrawingsmetamorfose tot laervlak groenskis fasies (250 ± 50ºC; ~2 kbars) ondergaan het. Hulle word mineralogies en geochemies geklassifiseer as litiese areniete en grouwakke. Die Tankwa subkom sandsteenlae is effens meer volwasse as die Laingsburg subkom sandsteenlae. Die lantanietgroep patroon vir die Tanqua en Laingsburg sandsteenlae is eenders, wat aandui dat beide deel gevorm het van dieselfde evolusionêre ontwikkeling en dat die sedimente een gesamentlike oorsprong gehad het, naamlik ‘n brongebied bestaande hoofsaaklik uit granitiese materiaal. Homogene εNd-waardes van ongeveer –5 by tye van afsetting vir al die sandsteen monsters dui daarop dat daar min of geen verandering in brongebied vir die Tankwa en Laingsburg subkom sedimente was nie. TCHUR model ouderdomme van 0.70 tot 0.95 Ga, en TDM model ouderdomme van 1.19 tot 1.49 Ga, is afkomstig van ‘n mengsel van Argeïese en Proterosoïese materiaal in onbekende hoeveelhede. Die mees waarskynlike brongebied is die Noord Patagoniese Gebergtes. Dit wys Nd isotopiese samestellings wat ooreenstem met ‘n gemiddelde εNd-waarde van –5 by 265 Ma.

Thesis (MSc (Conservation Ecology)--University of Stellenbosch, 2004. / 89 leaves single sided printed, preliminary pages i-xiv and numbered pages 1-89. Includes bibliography. List of tables, figures used. / Scanned with a Hp Scanjet 8250 Scanner to pdf format (OCR). / ENGLISH ABSTRACT: The main aim of an old field rehabilitation trial initiated in 2000 was to find a solution to the rehabilitation process for approximately 90 000 ha of unutilised land in the Little Karoo, South Africa. Depending only on a natural succession process to restore unutilised old fields would mean that the period of recovery would be longer than the life span of an average farmer. The trial, initiated by Witbooi in 2000 aimed to see how human intervention can facilitate the process of rehabilitation of old-fields. Three years later, the trial was again monitored to evaluate the success of reseeded indigenous species and method of cultivation in the rehabilitation process. A second objective was based on a result of Witbooi (2002) who showed that there was a tendency of 0. pes-caprae to invade disturbed areas, and aimed to evaluate the effect of this species on the rehabilitation process. Seven indigenous species were reseeded in 2000, of which only four species germinated and survived to the present. These surviving species are Pteronia incana Burm Dc., Tripteris sinuata DC., Ehrharta calycina SM and Chaetobromus dregeanus Nees. The highest level of recruitment in 2001 was recorded for T sinuata followed by P. incana, E. calycina and C. dregeanus. In September 2003, three years after the trial was initiated, the highest number of surviving seedlings were of T sinuata followed by E. calycina, C. dregeanus and P. incana. Five different cultivation methods were used to enhance the germination rate and survival of seedlings. The number of seedlings that survived differs according to the cultivation methods and soil type. Tripteris sinuata had the highest number of surviving seedlings in all cultivation methods off-heuweltjies. Tripteris sinuata was therefore selected to analyse the effect of various cultivation methods. The second objective was to study the impact of Oxalis pes-caprae on species diversity in restored old fields by assessing its ability to disperse in old fields under different cultivation methods. The multivariate ANOVA results showed that there was a significant difference in the density of O. pes-caprae between on and off heuweltjies (sites) and treatments (cultivation methods). There was a significant difference in the density of O. pes-caprae between cultivation methods. A Post Hoc LSD test showed a significant difference in the density of aboveground O. pes-caprae plants between control sites (no disturbance) compared to those sites that underwent some sort of soil disturbance. There was, however, no significant difference in the abundance of O. pes-caprae on plots that underwent some sort of disturbance (i.e Cleared vs Tilled vs Disked vs Ploughed sites) on heuweltjies. There was a significant difference in the number of O. pes-caprae bulbs collected between blocks (on and off-heuweltjie) and significant differences between cultivation methods. There was also a significant difference in bulb diameter between cultivation methods when compared between on and off-heuweltjie sites. The bulbs were classified into four measurement classes. The highest number of small (2-5 mm diameter) and medium (5-8 mm diameter) sized bulbs were found in the Tilled cultivation method. In contrast the Control treatment (uncultivated) had the highest number of large sized bulbs (14-17 mm diameter) and medium bulbs size categories. In conclusion, T. sinuafa has the potential to be used for rehabilitation of old fields in combination with Tilled cultivation method. Attention should be paid to the effect of O. pes-caprae especially on heuweltjies where this species showed a complete dominance in the rehabilitation trial. / AFRIKAANSE OPSOMMING: Die hoof doel van 'n ou veld rehabilitasie eksperiment wat in 2000 geinisieer is was om 'n oplossing te vind vir die rehabilitasie proses vir ongeveer 90 000 ha onbenutte land in die Klein Karoo, Suid-Afrika. Indien daar slegs op natuurlike suksessie prosesse staatgemaak word om die onbenutte ou lande te restoreer, sou dit beteken dat die periode van herstel langer sou wees as die lewensverwagting van die gemiddelde boer. Hierdie eksperiment, wat in 2000 deur Witbooi geinisieer is, het gepoog om te bepaal hoe menslike inmenging die proses van rehabilitasie van ou velde kan fasiliteer. Drie jaar later is die eksperiment weer gemonitor om die sukses van die teruggesaaide inheemse spesies en bewerkings-metodes in die rehabilitasie proses te evalueer. 'n Tweede doelwit is gebaseer op 'n resultaat van Witbooi (2002) wat aangetoon het dat daar 'n neiging was vir O. pes-caprae om versteurde areas binne te dring, en het dus gemik om die effek van hierdie spesie op die rehabilitasie proses te evalueer. Sewe inheemse spesies is in 2000 teruggesaai, waarvan slegs 4 spesies ontkiem en oorleef het tot die hede. Hierdie oorlewende spesies is Pteronia incana Burm Dc., Tripteris sinuata DC., Ehrharta calycina SM en Chaetobromus dregeanus Nees. Die hoogste vlak van werwing in 2001 is vir T sinuata aangeteken, gevolg deur P. incana, E. calycina en C. dregeanus. In September 2003, drie jaar na die aanvang van die eksperiment, was die hoogste getal oorlewende saailinge die van T sinuata, gevolg deur E. calycina, C. dregeanus en P. incana. Vyf verskillende bewerkings-metodes is gebruik om ontkiemingstempo en saailing oorlewing aan te help. Die aantal saailinge wat oorleef het varieer volgens die bewerkings-metode wat gevolge is en die grondtipe. Tripteris sinuata het die grootste aantal oorlewende saailinge gehad in al die bewerkings-metodes af van heuweltjies. Tripteris sinuata is daarom geselekteer om te analiseer vir die effek van verskillende bewerkings-metodes. Die tweede doelwit was om die inpak van Oxalis pes-caprae op spesie-diversiteit in die gerestoreerde ou land te bepaal deur die vermoë van hierdie spesie om in ou velde te versprei onder verskillende bewerkings-metodes te evalueer. Die multi-veranderlike ANOVA resultate het aangetoon dat daar 'n beduidende verskil in O. pes-caprae digtheid tussen heuweltjie en nie-heuweltjie (persele) en verskillende bewerkings-metodes was. Daar was 'n beduidende verskil in die digtheid van o. pes-caprae tussen verskillende bewerkingsmetodes. 'n Post Hoc LSD toets het 'n beduidende verkil in die digtheid van bogrondse O. pes-caprae plante tussen kontrole terreine (geen versteuring) vergeleke met persele wat een of ander vorm van grondversteuring ondergaan het aangedui. Daar was egter geen beduidende verskil in die volopheid van 0. pes-caprae op persele wat een of ander vorm van versteuring ondergaan het (i.e Skoongemaakte vs Getilde vs Geskottelde vs Geploegde persele) op heuweltjies nie. Daar was 'n beduidende verskil in die aantal O. pes-caprae bolle wat versamel is tussen blokke (op en af van heuweltjies) en beduidende verskille tussen die bewerkings-metodes. Daar was ook 'n beduidende verskil in bol-deursnitte tussen bewerkings-metodes wanneer dit tussen heuweltjie en nie-heuweltjie persele vergelyk is. Die bolle is in vier metingsklasse verdeel. Die grootste aantal klein (2-5 mm deursnit) en medium (5-8 mm deursnit) bolle is in die Getilde bewerkings-metode gevind. In kontras het die Kontrole behandeling (onbewerk) die grootste aantal groot (14-17 mm deursnit) en medium bolle gehad. Samevattend het T. sinuata die potensiaal om gebruik te word in die rehabilitasie van ou lande in kombinasie met die tilting bewerkings-metode. Aandag moet geskenk word aan die effek van 0. pes-caprae, veral op heuwetjies waar hierdie spesies 'n totale dominansie in die rehabilitasie eksperiment getoon het.

Thesis (MSc)--Stellenbosch University, 2005. / ENGLISH ABSTRACT: Fan System 5 forms the uppermost submarine fan system of the Permian-age Tanqua Fan Complex (Ecca Group) of the southwestern Karoo Basin. It is the most widespread system and represents the final phase of fan deposition in the Tanqua sub-basin. Depositional characteristics differ markedly from the rest of the fan systems, mainly because it lacks sedimentary features indicative of a single point source basin floor fan. The entire system consists of six different stages of fan growth and development in the lower slope settings. A hypothetical model was composed for Fan System 5 to understand the spatial/temporal distribution of reservoir and seal facies in slope turbidite settings. The facies vary from massive amalgamated sandstone beds to thin-bedded, ripple cross-laminated sand and siltstone beds. A thick shale unit identified as a regional marker layer overlies Fan System 5. lts base is defined by the presence of a regionally developed 20 cm thick hemipelagic shale unit. Six sand-rich units with channel-complexes are present in the Klein Hangklip, Groot Hangklip, Kalkgat, Tongberg, Skoorsteenberg and Blauwkop localities. The facies characteristics in the southernmost outcrops of Fan System 5 (Groot Hangklip, Tongberg and Kalkgat) reflect deposition in a lower slope setting where local structural control seems to have played a major role in the distribution and regional development of channel-fill and overbank depositional elements. The channel-fills are arranged in vertical to off-set stacking patterns and are comprised of massive, amalgamated [me to very fine-grained sandstone units up to 30 m in thickness. They are separated by thinner sandstone/siltstone units of varying thickness. The channelization displayed by the more proximal outcrops are interpreted to represent an upper fan, deposited in a lower- to mid-slope setting. In contrast to the channel-fill deposits at Skoorsteenberg, Klein Hangklip and Groot Hangklip, ripple cross-laminated overbank deposits, associated with smaller channel-fill units, predominate in the northeastern and eastern parts of the outcrop area. Massive- and thinbedded frontal sheet sandstones constitute the down-dip extensions to the most northern outcrops of Fan System 5. Highly erosive, stacked base-of-slope channel complexes, seemingly controlled by subtle early structural features, were able to construct significant thicknesses of regionally well-developed overbank deposits, marginal to the channel complexes. These facies changes occur over relatively short distances, which hold significant implications for the prediction of and the heterogeneity of reservoir facies in slope settings. Gradients are much steeper in the lower slope to mid-slope area than on the proximal basin floor. The occurrence of soft-sediment deformation in the overbank and upper parts of the channel-fill deposits supports a slope origin. Weakly developed wave-ripple marks in the uppermost layers of Fan System 5 further indicate that water depths approached wave base prior to deposition of the upper markerbed shales. Paleotransport for Fan System 5 was towards the north, northeast and east. The palaeocurrent directions of the channel-fill complexes in Klein- and Groot Hangklip seem to roughly correspond to the structural trend of synclinal depressions in this area. However, the effect and influences of basin floor topography and structural features on deposition were determined to be minimal on the regional development and local facies control of the fan. / AFRIKAANSE OPSOMMING: Waaiersisteem 5 vorm die laaste submarine waaiersisteem van die Perm-ouderdom Tankwa Waaierkompleks (Ecca Groep) in die suidwestelike Karoo-kom. Dit vorm die mees wydverspreide sisteem en verteenwoordig ook die fmale fase van waaierafsetting in die Tankwa sub-kom. Afsettingseienskappe verskil aansienlik van die onderliggende waaiersisteme, omdat kenmerkende sedimentêre eienskappe van 'n enkele toevoer bron ontbreek. Die hele sisteem bestaan uit ses verskillende periodes van waaiergroei en ontwikkeling in die laer kornhelling omgewmgs. 'n Voorspellingsmodel is opgestel vir Waaiersisteem 5 om die ruimtelike/temporele verspreiding van die reservoir en seël fasies in kornhelling turbidiet omgewings te kan verstaan. Hierdie fasies varieer van massiewe, geamalgameerde sandsteen tot dun gelaagde riffel- lamineerde sand- en sliksteenlae. 'n Dik regionale skalie eenheid oorlê Waaiersisteem 5 en vorm die boonste merkerlaag. Die basis word onderlê deur 'n 20 cm dik regionaalontwikkelde hemipelagiese skalie laag wat die onderste merkerlaag vorm. Ses sandige eenhede met geassosieerde kanaalkomplekse is onderskeidelik teenwoordig in: Klein Hangklip, Groot Hangklip, Kalkgat, Tongberg, Skoorsteenberg en Blauwkop omgewings. Die fasies-eienskappe van die mees suidelike dagsome van Waaiersisteem 5 (Tongberg, Groot Hangklip en Kalkgat) toon afsetting in 'n laer kornhelling omgewing, waar plaaslike tektoniese effekte moontlik 'n groot rol gespeel het in die verspreiding en regionale ontwikkeling van die kanaalvulsels en geassosieerde oewerwal-afsettings. Die gestapelde, wegstand kanaalvulsels-afsettings bestaan uit massiewe, geamalgameerde fyn tot baie fynkorrelrige sandsteen eenhede, wat diktes tot ongeveer 30 m kan bereik. Dit word van mekaar geskei deur dun sandsteenlsliksteen eenhede van afwisselende diktes. Die kanaal komplekse in die mees proksimale dagsome word interpreteer as 'n bo-waaier, wat afgeset is in 'n laer- tot middel kornhelling omgewmg. In teenstelling met die kanaalvulsels in die Skoorsteenberg, Klein Hangklip en Groot Hangklip omgewings, domineer riffel kruisgelamineerde oewerwal-afsettings, geassoseer met klein kanaalvulsels, die noordoostelike en oostelike dagsome van Waaiersisteem 5. Massiewe en dungelaagde frontale plaat sandstene, kom voor in die distale helling-omgewings in die mees noordelike dagsome van Waaiersisteem 5. Hoogs eroderende, gestapelde kanaalkomplekse, aan die basis van die komhelling wat moontlik beheer is deur vroeë komvloer topografie, was die oorsaak vir regionaal goed-ontwikkelde oewerwalafsettings. Hierdie fasies-verandering vind plaas oor 'n baie kort afstand wat betekenisvolle gevolge inhou vir die voorspelling van heterogeniteit van petroleum reservoir fasies in komhelling afsetting-omgewings. Die gradiënt vir die laer komhelling tot mid-komhelling omgewings is baie steiler as die distale komvloer omgewings. Die voorkoms van sagte-sediment deformasies in die oewerwal en boliggende dele van die kanaalvulsels weerspeël 'n moontlike komhelling omgewing. Swakontwikkelde golfriffelmerke in die boonste lae van Waaiersisteem 5 dui 'n waterdiepte aan wat nabyaan golf-basis is, voordat dit deur diepmariene skalies oorlê word. Paleovloeirigtings vir Waaiersisteem 5 was in 'n noord, noordoostelike en oostelike rigting. Die paleovloeirigting vir die Klein- en Groot Hangklip kanaalkomplekse stem min of meer ooreen met die strukturele grein van die sinklinale laagtes in die omgewing. Die effek en beheer van komvloer topografie en ander strukturele faktore op afsetting was minimaalop die regionale ontwikkeling en plaaslike fasies verspreiding van die waaier.

The leopard tortoise (Geochelone pardalis) is the largest of the southern African tortoise species and has a wide distribution range. However, there is a lack of ecological and physiological information about the species, especially arid and semi-arid regions. The Nama-Karoo, an arid region of South Africa, is subject to large fluctuations in rainfall, food availability and ambient temperatures (Ta). This study focused on the thermal behaviour, thermoregulatory, digestive and metabolic plasticity of the leopard tortoise within the Nama- Karoo biome. Seasonal changes in activity patterns and body temperature (Tb) were investigated in free ranging leopard tortoises in the Nama-Karoo. Leopard tortoises had unimodal daily activity patterns in winter, bimodal in summer, and there were daily and seasonal differences in the extent to which certain behaviours were practiced. Daily activity behaviours were executed at lower Tb and at lower Ta in winter compared to summer. In summer, core Tb of all tortoises oscillated on a daily basis well below maximum Ta, while core Tb of all tortoises in winter oscillated well above the daily Ta range. Tortoises were therefore able to maintain their Tb independently of Ta. Differences in Tb as measured from various positions on the tortoises body was investigated in relation to Ta. There was a strong seasonal and temporal influence on the relationship between various Tb’s, with the skin and external shell temperatures being more variable in response to fluctuating Ta’s compared with cloacal and core Tb. Cloacal temperatures were significantly different to other Tb measurements suggesting that it should be treated with circumspection as an exclusive measure of Tb. Heating and cooling rates of leopard tortoises were investigated in the field and under controlled laboratory conditions to determine if the tortoises maximise operational daily activity periods, and to determine the effect of behaviour and size on the rate of heat flux. In the laboratory, cooling rates were faster than heating rates in summer and winter for all size classes and decreased with increasing body mass. Leopard tortoises had significantly faster heating and cooling rates in winter than in summer. Free-ranging leopard tortoises had faster heating rates than cooling rates and their heat flux was largely independent of Ta. Heating and cooling rates were dependant on body mass and surface area-to-volume ratio of individuals. Under experimental conditions, tortoises physiologically adjusted their rate of heat flux, while free-ranging tortoises used physiological and behavioural mechanisms to minimise the risk of overheating, to aid thermal inertia and maximise operative activity time. Seasonal climatic cycles and fluctuating daily temperatures influence the oxygen consumption (VO2) of reptiles, however the result of these effects on metabolism in chelonians is poorly understood. The effect of seasonal and daily differences in Ta on VO2 was investigated. Leopard tortoises’ VO2 was slightly higher than reported for other chelonians. There were significant differences in tortoise VO2 at different Ta’s during the day and night and in different seasons. This metabolic plasticity is possibly an adaptive mechanism to cope with unpredictable environmental conditions. Unpredictable climatic conditions lead to unpredictable food and water availability. Little is known how tortoises adjust dietary parameters in response to food type and water availability, and if this affects body mass, energy and water balance. Therefore this study also considered whether leopard tortoises adjusted food transit rate, food intake and water loss to cope with a diet fluctuating in fibre and water content, and whether body mass, energy and water balance were maintained. Leopard tortoises fed a high fibre, low water content diet had lower food intake rates, longer food transit times, but lower daily energy assimilation compared with tortoises fed a low fibre, high water content diet. Tortoises fed a high fibre, low water content diet had lower urine osmolality, but similar total water loss to those fed a high fibre, low water content diet. The results indicate that tortoises can adjust digestive parameters according to diet composition and exercise some control over energy and water balance. It is concluded that leopard tortoises show a high degree of plasticity in their thermal behaviour and physiology which allows survival in an unpredictable environment, particularly where there are fluctuations in rainfall, food availability and Ta’s. Seasonal and daily variation in thermoregulation, metabolic rate and the uptake of energy allows the leopard tortoise to maximise the duration of operative temperature, to minimise energy loss and to use variable and unpredictable seasonal resources. / Thesis (Ph.D.)-University of KwaZulu-Natal, Pietermaritzburg, 2007.