Dissertations / Theses: 'South Coast'

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Ndzeng, Nyangone Emmanuel. "South Africa's relations with Gabon and the Ivory Coast : 1969-1994 /." Link to the online version, 2008. http://hdl.handle.net/10019.1/1138.

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2

Nichol, Scott L. (Scott Lawrence). "Sedimentology of two wave-dominated, incised valley estuaries, New South Wales south coast." Thesis, Department of Geography, 1992. http://hdl.handle.net/2123/8918.

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Joubert, J. R. "An investigation of the wave energy resource on the South African Coast, focusing on the spatial distribution of the South West coast." Thesis, Link to the Internet, 2008. http://hdl.handle.net/10019.1/351.

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4

Mondello, Nicholas. "Physical oceanography off the South Coast of Western Australia." Thesis, Mondello, Nicholas (2017) Physical oceanography off the South Coast of Western Australia. Honours thesis, Murdoch University, 2017. https://researchrepository.murdoch.edu.au/id/eprint/40163/.

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Compared to neighbouring regions of ocean, the south coast of Western Australia (WA) has received relatively little scientific attention despite a range of Australian Commonwealth marine protected areas having been established in the region as of 2012. The ocean off the south coast of WA is characterised by a canyon-dense continental shelf edge including the Bremer Canyon, a shelf edge canyon of approximately 8 km width. There are also two main currents in the region, the eastward flowing Leeuwin Current (LC) situated above the continental shelf edge, and the westward flowing Flinders Current (FC) situated south of the continental shelf. The Blue-link Reanalysis (BRAN) ocean forecasting model simulates the currents, temperature and salinity around Australia at daily intervals from 1994 – 2016 with 1/10th degree resolution. It has been speculated that these currents may interact with the canyons along the shelf edge to induce oceanographic conditions conducive to increased pelagic productivity and ecological diversity. This study was a two-part investigation of the physical oceanography off the south coast of WA with a focus on shelf edge dynamics near Bremer Canyon. It involved the use of the (BRAN) model and in situ data including conductivity, temperature and depth (CTD) profiles during January 2017 and temperature logger measurements from near Bremer Canyon between 2015 and 2017. The BRAN outputs were in close agreement with previous studies of the LC and FC and showed that the mixed layer depth (MLD) was shallowest (<50 m) in summer and deepest in winter (>200 m), in sync with seasonal heat flux. The CTD results were within one SD of the average BRAN profiles and MLD results for January. The volume transport of the LC and strong westerly wind events were dominant drivers of the temperature variation along the shelf edge during autumn and winter of 2015 as the warm LC water was forced downwards. In spring and summer, the volume transport of the LC was lowest (1.6 Sv) and other factors became dominating drivers of the shelf edge temperature variation including eddy kinetics and canyon-related processes. The BRAN outputs effectively simulated the mesoscale features examined in this study including the volume transport of the LC, westerly wind forced response and the influence of mesoscale eddies. These processes have the potential to influence the pelagic ecology through vertical mixing and upwelling.

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Van, Rooyen Suretha. "Factors affecting alien grass invasion into West Coast Renosterveld fragments." Thesis, Stellenbosch : Stellenbosch University, 2004. http://hdl.handle.net/10019.1/49964.

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Thesis (MSc)--University of Stellenbosch, 2004.
ENGLISH ABSTRACT: With only 1.76% conserved West Coast Renosterveld remaining it is crucial to prioritize the conservation and management of this fragile vegetation type. Because of its occurrence on fertile soils, renosterveld has been cleared for cultivation and other agricultural use and is thus fragmented to a critical point. These remaining fragments are subject to extensive edge effects and the exact parameters of a viable fragment must still be determined. The extent of alien grass species invasion into remnant renosterveld patches was determined using data collected using the line-intercept method. Sampling included three different management treatment areas adjacent to old lands: 1) a recently burned area, 2) a grazed area and 3) an unburnedlungrazed area providing a control sample. Additionally all small-scale soil disturbances along the lines were recorded. Results showed that Briza spp., Bromus spp. and Avena fatua were the most significant invading alien grass species. There was a significantly high variation between alien grass cover in each treatment, with the grazed area containing the highest overal! level of alien grass invasion. The control area, with the exclusion of fire and animal activity, showed minimum alien grass invasion. Edge effects were apparent in all treatments, but were lowest in the control area, where percentage alien grass cover significantly decreased after a distance of fifteen meters into the remnant patch. A weak positive correlation between the occurrence of alien grass and indigenous grass was found, as well as evidence of a weak association between alien grass cover and shrub cover. The possibility that small-scale soil disturbances could be an important contributing factor to alien grass invasion was supported by the positive correlation between disturbances and percentage alien grass cover. A positive correlation was found between the occurrence of indigenous grass and small-scale soil disturbances, while shrub cover tended to be less associated with animal activity. It is concluded that the correct management regime could effectively control the excessive invasion of alien grass species into the remnant renosterveld patches. Grazing (including all animal activity and small-scale soil disturbances) was the main facilitator of alien grass establishment - even dominating the prominent consequences of edge effects by facilitating alien grass establishment much deeper into the remnant patches. It could be assumed that a precise balance of low-pressure grazing and fire management should be established to enable the effective control of alien grass species while maintaining optimum biodiversity. Keywords: renosterveld, alien grass, grazing, fire, management, small-scale soil disturbances
AFRIKAANSE OPSOMMING: Met slegs 1.76% oorblywende Weskus Renosterveld wat bewaar word, is die beskerming en effektiewe bestuur van hierdie bedreigde plantegroei 'n prioriteit. Die vrugbare grond waarop renosterveld voorkom, het veroorsaak dat dit uitgeroei word om eerder die kultivering van ekonomies produktiewe landbou gewasse moontlik te maak. Dus het renosterveld verminder en gefragmenteer tot 'n kritieke punt. Hierdie ooblywende klein areas bedek met renosterveld, is blootgestel aan ekstensiewe invloede van die omliggende areas en die presiese afmetings vir 'n effektiewe grate renosterveld fragment vir bewarings doeleindes, moel nog vasgestel word. Die male van uitheemse gras spesie indringing in hierdie renosterveld fragmente is ondersoek deur die versameling van data deur die lyn-onderskep metode. Drie verskillende bestuursstelsels vir renosterveld is ondersoek om vas te stel wat die ergste graad van uitheemse gras indringing voorkom. Die studie het 'n 1) onlangs gebrande area, 2) 'n beweide area en 3) 'n kontrole area (wat nie gebrand of bewei is nie) ondersoek. Alle kleinskaalse grond-versteurings langs die lyne is ook aangeteken. Die resultate het aangetoon dat Briza spp., Bromus spp. en Avena fatua, as uitheemse grasse, die belangrikste indringers was en dus die grootste bedreiging inhou. Daar was 'n beduidende hoë variasie tussen die mate van uitheemse gras bedekking aangeteken in elk van die bestuurs-stelsels. Die beweide area het die hoogste graad van uitheemse gras indringing getoon, terwyl die kontrole area (in die afwesigheid van vuur en weidings aktiwiteite) die meeste weerstand teen uitheemse gras indringing getoon het. Die invloed van die omliggende omgewing was ook duidelik sigbaar in al drie die bestuurs-stelsels, maar was duidelik minder in die kontrole area waar die persentasie uitheemse gras indringing aansienlik verminder het na 'n afstand van vyftien meter in die renosterveld fragment in. 'n Swak positiewe korrelasie tussen die voorkoms van uitheemse grasse en inheemse gras spesies was aangeteken, asook bewyse van 'n swak negatiewe assosiasie tussen die uitheemse gras spesies en die inheemse bosse. Soos verwag, is daar bewyse gevind vir die teorie dat kleinskaalse grond-versteurings 'n belangrike fasiliterende faktor is vir uitheemse gras vestiging. Daar was 'n duidelike positiewe korrelasie tussen hierdie grond-versteurings en die persentasie uitheemse gras grondbedekking. Dieselfde positiewe assosiasie was gevind tussen die inheemse gras en hierdie kleinskaalse grond-versteurings, terwyl die inheemse bossie duidelik minder verbind was met die verskynsel. Die gevolgtrekking is gemaak dat 'n korrekte bestuurs-plan die indringing van uitheemse grasse effektief sal kan beheer. Dier aktiwiteite (insluitende beweiding, grawe van gate, mier en termiet neste ens.), en dus kleinskaalse grond-versteurings. was die grootste fasiliteerders van uitheemse gras indringing en vestiging binne hierdie renosterveld stukke. Dit oorheers selfs die aansienlike effek wat invloede van die omringende omgewing op hierdie areas het, deur die uitheemse gras indringing selfs dieper in die fragmente in aan te help. Daar kan dus aangeneem word dat 'n presiese balans tussen lae-intensiteit beweiding (en dus fauna aktiwiteit) en veld brande vasgestel moet word vir die effektiewe beheer van uitheemse gras spesies terwyl die optimum bio-diversiteit terselfde tyd gehandhaafword. Sleutelwoorde: renosterveld, uitheemse grasse, beweiding, vuur, veldbestuur, kleinskaalse grond-versteurings

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Kaminsky, Alexander. "Social capital and fisheries co-management in South Africa: the East Coast Rock Lobster Fishery in Tshani Mankozi, Wild Coast, Eastern Cape." Thesis, Rhodes University, 2012. http://hdl.handle.net/10962/d1003110.

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It is evident that natural fish stocks are in rapid decline and that millions of people around the world rely on these resources for food and for securing a livelihood. This has brought many social scientists, biologists and fisheries experts to acknowledge that communities need to take more control in managing their natural resources. The paradigm shift in fisheries management from a top-down resource orientated control to a participatory people-centred control is now being advocated in many maritime nations in facilitating community-based natural resource management. At the heart of these projects is the establishment of institutions and social networks that allow for clear communication and information sharing, based on scientific data and traditional knowledge which ultimately allow empowered communities to collectively manage their resources in partnership with government, market actors and many other stakeholders. Central to the problem is the issue of access rights. In many situations where co-management of natural resources through community-government partnerships is advocated, the failure of coastal states to provide adequate legislature and regulatory frameworks has jeopardised such projects. A second issue is the failure of many states to provide adequate investments in social and human capital which will enable communities to become the primary stakeholder in the co-management of their natural resources. Whilst investments like capacity building, education, skills training and development, communications and institution building can initially require high financial investments, the regulatory costs for monitoring, controlling and surveying fish stocks along the coastline will go down as communities take ownership of their resources under sustainable awareness. The main unit of investment therefore is social capital which allows for the increase in trust, cooperativeness, assertiveness, collective action and general capabilities of natural resource governance. High levels of social capital require good social relations and interactions which ultimately create a social network of fishers, community members and leaders, government officials, market players, researchers and various other stakeholders. Co-management thus has an inherent network structure made up of social relations on a horizontal scale amongst community members as well as on a vertical scale with government and fisheries authorities. These bonding relations between people and the bridging relations with institutions provide the social capital currency that allows for a successful co-management solution to community-based natural resource governance. The South African coastline is home to thousands of people who harvest the marine resources for food security and securing a basic income. Fishing is a major cultural and historical component of the livelihoods of many people along the coastline, particularly along the Wild Coast of South Africa located on its South-eastern shoreline. Due to the geopolitical nature of South Africa’s apartheid past many people were located in former tribal lands called Bantustans. The Transkei, one of the biggest homelands, is home to some of South Africa’s poorest people, many of whom rely on the marine resources. By 1998 the government sought to acknowledge the previously unrecognised subsistence sector that lived along the South African coastline with the promulgation of the Marine Living Resources Act. The act sought to legalise access rights for fishers and provide opportunities for the development of commercial fisheries. The act and many subsequent policies largely called for co-management as a solution to the management of the subsistence sector. This thesis largely explains the administrative and legislative difficulties in transporting the participatory components of co-management to the ground level. As such co-management has largely remained in rhetoric whilst the government provides a contradictory policy regarding the management of subsistence and small-scale fishers. This thesis attempts to provide qualitative ethnographic research of the East Coast Rock Lobster fishery located in a small fishing village in the Transkei. The fishery falls somewhere on the spectrum between the small-scale and subsistence sector as there are a basket of high and low value resources being harvested. It will be argued that in order to economically and socially develop the fishery the social capital and social networks of the community and various stakeholders needs to be analysed in order to effectively create a co-management network that can create a successful collective management of natural resources thereby sustaining these communities in the future.

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7

Liengme, Christine Anne. "West Coast strandveld : its utilization and management." Thesis, University of Cape Town, 1987. http://hdl.handle.net/11427/26136.

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8

Barwell, Lauriston. "Integrity assessment procedure for buffer dune systems on the Cape South Coast, South Africa." Thesis, Stellenbosch : University of Stellenbosch, 2011. http://hdl.handle.net/10019.1/6524.

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Thesis (MScEng (Civil Engineering))--University of Stellenbosch, 2011.
ENGLISH ABSTRACT: The hypothesis postulated in this research, namely that the effectiveness of natural and constructed buffer dune systems can be assessed by a set of indicators that defines the integrity of the dune system and triggers informed management decisions, was evaluated and proved to be essentially true. Two key objectives, namely (1) the identification of key indicators that define the buffer dune integrity; and (2) the development of a scientifically defendable and practical checklist-based method of gathering qualitative information on the identified key indicators so as to guide decision-making at municipal level formed the core of the study. The six dune integrity indicators that collectively define the risk profile of a particular site along the Southern Cape coastline are (1) the degree of protection from prevailing wave energy, (2) the characteristics of the dominant winds and sand supply during the dry season, (3) the relative height of the foredune, (4) the degree of pressure on the buffer dune due to humans, (5) the vulnerability of the type of coastline to erosion, and (6) the coastline stability considering the prevailing coastal processes. The first two indicators relate to the natural (permanent) characteristics of the site and can be defined by experts and presented in the form of a risk and vulnerability atlas layer for direct use by non-experts. The third and fourth indicators relate directly to the implementation of proactive assessment and appropriate management actions to ensure a high level of buffer dune integrity. The last two indicators allow for management intervention to reduce the vulnerability but may entail costly engineering solutions and require expert input. A conceptual risk profile assessment procedure and a decision support guideline incorporating these indicators were developed and evaluated for relevance and practicality through a series of workshops with municipal officials along the south coast of South Africa. It was seen that although some initial basic training may be required, carrying out rapid assessments of the environmental status of key components of an identified human–nature system, such as a buffer dune, is practical and achievable by non-experts.
AFRIKAANSE OPSOMMING: Die hipotese wat in hierdie navorsing gepostuleer is, naamlik dat die doeltreffendheid van natuurlike en geboude bufferduinstelsels geassesseer kan word deur ’n stel aanwysers wat die integriteit van die duinstelsel bepaal en ingeligte bestuursbesluite tot gevolg het, is getoets en bewys hoofsaaklik waar te wees. Twee sleuteldoelwitte, naamlik (1) die identifisering van sleutelaanwysers wat die bufferduinintegriteit bepaal; en (2) die ontwikkeling van ’n praktiese kontrolelys-gebaseerde metode wat wetenskaplik verdedigbaar is om kwalitatiewe inligting oor die geïdentifiseerde sleutelaanwysers in te samel ten einde besluitneming op munisipale vlak te bevorder, vorm die kern van die studie. Die ses duin-integriteitsaanwysers wat gesamentlik die risikoprofiel van ’n bepaalde terrein langs die kuslyn bepaal, is (1) die graad van beskerming teen die heersende golfenergie, (2) die kenmerke van die dominante winde en sandbron gedurende die droë seisoen, (3) die relatiewe hoogte van die voorduin, (4) die graad van druk op die bufferduin as gevolg van mense, (5) die eroderingskwesbaarheid van die soort kuslyn, en (6) die kuslynstabiliteit met inagname van die kusprosesse. Die eerste twee aanwysers het betrekking op die natuurlike (permanente) eienskappe van die terrein en kan deur kundiges bepaal word en in die vorm van ’n kaart in ’n risiko-enkwesbaarheidsatlas aangebied word vir direkte gebruik deur niedeskundiges. Aanwysers 3 en 4 hou direk verband met die implementering van tydige en deurlopende proaktiewe assessering en gepaste bestuursaksies om ’n hoë vlak van bufferduinintegriteit te verseker. Aanwysers 5 en 6 bevorder bestuursaksies om kwesbaarheid te verminder, maar kan moontlik duur ingenieursoplossings inhou en kundige insette benodig. ’n Konseptuele risikoprofielassesseringsprosedure en ’n besluitondersteuningsriglyn wat die aanwysers insluit, is ontwikkel en geëvalueer vir toepaslikheid en uitvoerbaarheid deur ’n reeks werkswinkels met munisipale amptenare aan die suidkus van Suid-Afrika. Hoewel aanvanklike basiese opleiding nodig kan wees, bly dit dat vinnige assessering van die omgewingstatus van sleutelkomponente van ’n geïdentifiseerde mens–natuurstelsel, soos ‘n bufferduin, prakties en haalbaar deur niedeskundiges is.

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Busakwe, Nolukholo Sinovuyo. "Stratigraphy and sedimentology of the Msikaba formation in KwaZulu Natal South Coast, South Africa." Thesis, University of Fort Hare, 2015. http://hdl.handle.net/10353/2501.

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The Msikaba Formation is a Late Devonian fluvial and marine succession which outcrops from Hibberdene to Port Edward along the south coast of KwaZulu-Natal Province, South Africa. The Formation is composed of brownish conglomerate at the bottom and white-greyish quartz arenite sequence in the middle and mixed quartz-arenite with feldspathic sandstone in the upper sequence. Previous studies put more emphasis on the correlation of Msikaba Formation with the Natal Group and Cape Supergroup, whereas this study revised the stratigraphy, and also put new insight on the petrography, sedimentary facies, depositional environments and diagenesis of the Formation. The total stratigraphic section attains a thickness of 184 m at Margate area and 186 m at Port Edward area. The stratigraphy of Msikaba Formation is well exposed on the outcrops along the KwaZulu-Natal coastline. The stratigraphy is subdivided into 4 new members along Margate to Shelly beach section; namely Manaba Member, Uvongo Member, Mhlangeni Member and Shelly Beach Member from bottom upward. Twelve sedimentary facies were identified and the sedimentary facies were integrated into 4 facies association: Facies association 1 (Gmm+Sm) represents braided fluvial deposits, Facies association 2 (Gcm+St+Sp+Sl+Shb) represents tidal channel and tidal flat deposit, Facies association 3 (St+Sp+Sr+Sl) is result of shallow marine deposit and Facies association 4 (Sp+Sl+St+Sm) is a mixed marine and fluvial deposit. Each facies association represents a specific stratigraphic unit and were deposited in a specific sedimentary environment. Grain size analysis was conducted on seventeen thin sections and 500 grains were counted from each thin section. The sandstone grain size parameters of mean, sorting, skewness and kurtosis fell under the average of 0.75, 0.78, 0.4 and 1.2φ respectively. The results show that most of the grain size are coarse to medium grained throughout the study areas and sorting of the sandstones are moderate to poorly sorted. The cumulative frequency diagrams and bivariate plots show positive skewness and negative kurtosis, which indicate a high hydrodynamic environment. Modal composition analysis and petrography studies show that detrital components of the Msikaba Formation are dominated by monocrystalline quartz, feldspar (mostly K-feldspar) and lithic fragments of igneous and metamorphic rocks. The sandstones could be classified as quartz arenite, sub-arkosic sandstone and feldspathic litharenite; and the provenance analysis indicates that the sandstones were derived from craton interior, recycled or quartzose recycled sources which may derived from weathering and erosion of igneous and metamorphic rocks. Diagenetic processes of the Msikaba Formation have been passed through early, mid- and late diagenetic stages. Cementation, mineral conversion and compaction affect early diagenetic stage; authigenic minerals, quartz and feldspar overgrowth are presented in mid-diagenetic stage, whereas recrystallization, replacement, deformation and dissolution have been strongly affected late diagenetic stage. Microscopy, XRD and SEM-EDX studies have identified five types of cements including smectite clay, kaolinite, hematite, quartz and feldspar cements. Quartz cement, pore-filling and pore-lining clay are the major type of cements in the Msikaba Formation. Based on the lithology, sedimentary structure and facies variations, the Manaba Member was most probably deposited in a braided fluvial environment, the Uvongo Member was deposited in a tidal channel environment, the Mhlangeni Member was formed in shallow marine storm-influenced environment, whereas the Shelly Beach Member was represented mixed marine and fluvial environment. The sequence stratigraphy of Msikaba Formation constitutes a transgressive sequence from Manaba Member to Uvongo Member, whereas it ended as a regressive sequence from Mhlangeni Member to Shelly beach Member. The Msikaba Formation shows major differences with the Natal Group and Table Mountain Group (Cape Supergroup) in the lithology, stratigraphic sequence, sedimentary structures, facies system, palaeocurrent styles, fossil contents and depositional environments, which demonstrate that they are not the equivalent stratigraphic unit. Therefore, the Msikaba Formation is a separate, younger stratigraphic unit, and cannot correlate with the Natal Group and Table Mountain Group as suggested by previous researchers.

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Van, der Merwe Elizabeth. "Systematics of the non-geniculate coralline red algae from the South African south coast." University of the Western Cape, 2015. http://hdl.handle.net/11394/4818.

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Philosophiae Doctor - PhD
The aim of this study was to document the intertidal and shallow subtidal species of non-geniculate coralline red algae from the South Africa south coast. The main emphasis of the study are encompassed in four research chapters and one concluding chapter focusing on: 1) the documentation of the non-geniculate coralline red algae occurring along the South Africa south coast; 2) revisiting the Leptophytum-Phymatolithon complex in order to resolve the taxonomic status of species previously ascribed to the genus Leptophytum from South African; 3) starting to prepare modern monographic accounts of the higher taxa; and 4) the production of updated keys to all the currently recognised taxa of non-geniculate coralline algae for South Africa. Although nowhere near complete, here we present our findings and report on the current biodiversity status of the non-geniculate coralline red algae after a further four years of extensive sampling.

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Esteban, Alamá Irene. "Reconstructing past vegetation and modern human foraging strategies on the south coast of South Africa." Doctoral thesis, Universitat de Barcelona, 2016. http://hdl.handle.net/10803/401426.

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The importance of South Africa lies in the many caves and rock shelters containing well preserved evidence of human activity, cultural material complexity and a growing number of early modern human fossils dating to the Middle Stone Age (MSA). South Africa also hosts the world's smallest floral kingdom, now called the Greater Cape Floristic Region (GCFR), with high species richness and endemism. We use phytoliths –amorphous silica particles that formed in epidermal cells of plants–in order to study the evolution of plant exploitation strategies by first modern humans and to understand the response of GCFR environments to glacial-interglacial cycles and rainfall shifts and its implication with the evolution of first modern humans that inhabited the south coast of South Africa during the Upper Pleistocene. In paleoanthropological research, improving our capacity to reconstruct past climatic and environmental conditions can help us to shed light on survival strategies of hunter- gatherers. To do this, one must use actualistic studies of modern assemblages from extant habitats to develop analogies for the past and improve paleoenvironmental reconstructions. Accordingly, this thesis contemplates fossil and modern material: i) archaeological sediment samples from Pinnacle Point 5-6 site (PP5-6) located on the south coast of South Africa; ii) modern plants from the GCFR and susceptible to have been exploited by first modern humans inhabiting the south coast; iii) modern surface soil samples from different GCFR vegetation types of the south coast of South Africa. The modern plant reference collection is the first quantitative and morphological study conducted with wood and leaves of trees and shrubs, leaves, bulb scale leaves and edible part of the bulb of geophytes, restios–Restionaceae and grasses–Poaceae from the GCFR on the south coast of South Africa. We observed that grasses are the highest phytolith producers among plant types. We reported through thin sections and SEM that the characteristic restio phytoliths belong to and characterize the Restionaceae family and have been detected in the parenchyma sheath of the culms. Geophytes did not produce diagnostic phytolith morphotypes that can be used for taxonomic identification what might make difficult their identification in the fossil record. The results of the modern surface soil samples showed that phytolith concentration relates mostly to vegetation types and the dominant vegetation rather than to the type of soils. More abundant phytoliths from Restionaceae and woody/shrubby vegetation are also noted from fynbos vegetation and grass phytoliths are a recurrent component in all the vegetation types in spite of being a minor component in the modern vegetation. The grass silica short cells (GSSCs) from these plants, however, suggest a mix of C3 and C4 grasses in most of the vegetation types with a major presence of the rondels ascribed to C3 grasses. The exceptions are riparian, coastal thicket and coastal forest vegetation, which are characterized by the dominance of C4 grass phytoliths. The study of the modern plants and soils from the surrounding areas of Pinnacle Point were used as proxy for the reconstruction of past human foraging strategies and paleoenvironmental reconstruction through the phytolith record from PP5-6 site. The study of the archaeological sediment samples from this site indicated a wide range of plants used by first modern humans inhabiting the area including wood, leaves and fruits of trees and shrubs, grasses and restios. We reported for the first time the presence of restios in the South African archaeological record through the study of phytoliths. From an environmental perspective, the changes observed in the phytolith record from Pinnacle Point deposits are indicative of vegetation movements accordingly to climate changes and sea level fluctuations, in a continuous regional mosaic of habitats.
Este trabajo de tesis tiene el objetivo último de conocer las estrategias de explotación de recursos vegetales de las poblaciones de primeros humanos modernos, así como la reconstrucción de la vegetación y el clima existente durante el Pleistoceno Medio y el Pleistoceno Final a través del estudio de fitolitos de los depósitos arqueológicos del abrigo rocoso de Pinnacle Point 5-6 (PP5-6). Para ello realizamos u Realiamos estudios actualísticos de plantas y suelos modernos como base análoga de nuestro estudio. Del estudio de plantas modernos dos son los principales resultados que se obtuvieron: i) a través de secciones delgadas y microscopio electrónico de barrido se caracterizó fitolitos diagnósticos de la familia Restionaceae (restios) en la vaina del parénquima de los tallos y ii) los geófitos no producen morfotipos diagnósticos que pudieran ser utilizados para su identificación taxonómica. Los resultados de los suelos mostraron que la concentración de fitolitos se relaciona principalmente con el tipo de vegetación y las plantan que ellos dominan. Los fitolitos característicos de restios dominan en la vegetación de tipo fynbos. Las células cortas de gramíneas (GSSC) sugieren una mezcla de gramíneas de tipo C3 y C4 en la mayoría de los tipos de vegetación. Las excepciones son la vegetación riparia y de coastal thicket donde gramíneas C4 dominan. El estudio de las muestras de sedimentos arqueológicos de PP5-6 indicó una amplia gama de plantas utilizadas por los habitantes de PP5-6. Identificamos por primera vez la presencia de restios en el registro arqueológico sudafricano a través del estudio de fitolitos. Desde una perspectiva ambiental, los cambios observados en el registro de fitolitos de los depósitos de Pinnacle Point son indicativos de los movimientos de vegetación en consecuencia a los cambios climáticos y las fluctuaciones del nivel del mar, en un mosaico regional continuo de hábitats.

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Slabber, Michelle Yvonne. "Accumulation and toxicity of metals in oysters (Striostrea margaritacea) from the South African South Coast." Thesis, Cape Peninsula University of Technology, 2013. http://hdl.handle.net/20.500.11838/2037.

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Thesis submitted in fulfilment of the requirements for the MTech: Oceanography in the Faculty of Applied Sciences at the CAPE PENINSULA UNIVERSITY OF TECHNOLOGY, 2013
The current status of metal pollution off the South African South coast is not well known. This study was the first to be undertaken in many years using Striostrea margaritacea as a subject species. The aims of the study were to determine the degree of metal contamination in the water, sediments, oyster tissues and oyster shells at sites selected in Witsand, Wilderness and Goukamma, as well as to establish if Striostrea margaritacea qualifies as a successful biomonitor when using lysosomal destabilization as a tool. Seasonal variations between sites were also considered. Other objectives, such as the potential of a Marine Protected Area (MPA) as a control site and the necessity of a monitoring program along the south coast were also included. Sites were sampled seasonally for one year at spring low tides. Ten oysters were collected from each individual site upon each visit. The Neutral Red Retention Time (NRRT) assay was used to determine lysosomal membrane integrity of oyster haemocytes, whereafter oysters were sacrificed for metal analyses. Metals that were analysed are aluminium (Al), copper (Cu), zinc (Zn) and iron (Fe). Metal analyses were done using an Inductively Coupled Plasma - Atomic Emission Spectrometer (ICP- AES). All statistical analyses were performed using ANOVA on Ranks to determine if there were significant differences between sites and between sampling occasions. Aluminium concentrations found in the water column at all sites were considered as low. Iron, zinc and copper concentrations within the water column can on the other hand be considered as high when comparisons are drawn with other studies and data sets. Sediment concentrations for all the metals within the present study were considered to be low when compared to other studies and guidelines. There were not many significant differences recorded between sites and no seasonal patterns were present. Within the tissues of the oysters, the metal ranges are considered to be low when compared to other studies. No definite conclusion about the contamination status of the oyster tissue could be drawn due to the lack of comparative literature. A field study in conjunction with a laboratory experiment should yield more reliable results. There were also no seasonal trends present and very few differences between sites. The bioaccumulation factors were considered as being low with a few exceptions where they were moderate when oyster tissue data was compared to water and sediment data. Concentrations for Al, Zn and Cu in the shells could be considered low when comparisons are drawn, with the exception of Fe that was found to be high. The bioaccumulation factors were considered to be low when oyster shell concentrations were compared to water and sediment data. There were also no seasonal trends present and a prolonged sampling period is suggested to further investigate these findings. When a comparison was drawn between the tissue and shell data a clear pattern was evident. Al and Fe concentrations were highest within the shell where as Zn and Cu concentrations were highest within the tissues of the animal. The theory of mineralization is supported by these findings where bivalves will use their shell as a reservoir for micronutrients and other substances. The NRRT assay revealed that lysosomal membrane destabilization had occurred and that the animals appeared to be stressed for the duration of the sampling period. Site 3, within the MPA, had the longest retention time. The retention times that were recorded were short when compared to other studies. This assay did however show potential as a basic monitoring tool from which more thorough investigations can be initiated. In conclusion, the study sites along the south coast of South Africa does not seem to be contaminated by Al, Zn, Cu or Fe when data is compared to international and local water quality guidelines, sediment quality guidelines and other studies. Also, as concentrations between sites did not differ greatly, it is inconclusive whether or not the MPA can be used as a reliable references site for in situ studies. More vigorous and lengthy studies should be undertaken to contribute to current knowledge of our indigenous species, Striostrea margaritacea and to aid in the development of better management of this resource as well as an ongoing monitoring programme.

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13

Burns, Michael Edmund Reid. "A synecological study of the East London coast dune forests." Thesis, Rhodes University, 1987. http://hdl.handle.net/10962/d1006134.

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Quantitative community descriptions, based on point quarter sample data, are made for a number of dune forest units along the East London coast. These are supported by multivariate classifications and ordinations which illustrate the inter community variation between the sampled seaward, landward and dune valley sites. Climax valley forest is floristically most characteristic and can be clearly distinguished from the seaward and landward thicket communities which tend to show a degree of similarity. Within-forest community differences are shown to be more significant than variation along the coast. This appears to indicate that climoedaphic gradients established laterally to the coast induce a greater floristic response than the rainfall gradient within the study area. The state of developnent within the dune soil profile and the rate and effect of salt spray deposition are considered to be important factors influencing dune forest succession and are discussed in some detail. An overview of certain other climatic variables as well as the geological features within the study area is also given. A phenology study of the dune forest, scrub-thicket and strand plant cornnunities shows some general patterns of flowering and fruiting phenorhythms. Although much variation was observed, there appears to be a bimodal hyperactive phenophase response which is thought to be related to rainfall or periods of favourable soil moisture conditions. A brief discussion of some of the positive and negative human influences on the coastline is given. This includes a description of the management activities carried out in the area as well as the demands placed on ·the coastal resource.

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Gusha, Molline Natanah C. "A community–wide trophic structure analysis in intertidal ecosystems on the south coast of South Africa." Thesis, Rhodes University, 2018. http://hdl.handle.net/10962/63312.

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Coastal ecosystems are more than microhabitats for marine species. Acting as atmospheric carbon filters, species in coastal environments are directly and/or indirectly associated with transferring organic carbon to species at higher trophic levels. However, the progressing change in global climatic conditions has created the need to assess the consequences of the shifting conditions on both direct and indirect interactions of physical and biological parameters at species and/or community levels. From these perturbations, the effects of biotic homogenization on ecosystem functioning and resilience can also be realised. Herein, I discuss the effects of temperature, nutrients, biotic interactions and habitat characteristics on community dynamics within intertidal rock pool systems on the south coast of South Africa using complementary qualitative and quantitative analytical methods. Seasonality had a significant impact on rock pool species with changes in composition and higher richness in winter than summer. The first two axes of the Canonical Correspondence Analysis (CCA) of the plant and animal communities each explained ~20% of the relationship between physico-chemical parameters and biological variables. The CCA highlighted that seasonal shifts in chlorophyll-a, conductivity, salinity, water depth, surface area and substratum type indirectly influenced species composition. For example, pools with heterogenous substratum comprising a mixture of sand and rock exhibited higher species diversity than homogenously bedded pools. Furthermore, a Bayesian analysis of community structure based on stable isotope ratios was used to assess how trophic pathways of carbon and nitrogen elements reflected community composition and richness. Isotopic biplots showed an increase in food web size, food chain length and the trophic positions of fish and some gastropods in winter compared to summer. There was greater dietary overlap among species in larger pools. In addition, while isotopic nearest neighbour distance and species evenness also showed a positive increase with pool size in summer, the same metrics were almost constant across all pool sizes in winter. These changes in food web packing and species evenness suggest seasonal preferences or migration of species in summer from small pools to larger pools with stable physico-chemical parameters. Furthermore, the presence of fish was seen to promote trophic diversity within some pools. The results from laboratory microcosm grazing experiments demonstrated significant direct and indirect effects of temperature and nutrients within plankton communities. Copepod grazing had an indirect positive influence on phytoplankton biomass and size structure while the interactive effects of temperature and nutrients had contrasting effects on both phytoplankton communities and copepod biomass. Shifts in water chemistry and nutrient treatments were also observed in the presence of copepods. Phosphate addition had a recognisable impact on plankton communities. The presented synthesis of the literature mainly highlighted that positive effects at one trophic level do not always positively cascade into the next trophic level which is evidence of complex interactive biotic, habitat and water chemistry effects within these intertidal ecosystems. Thus, to further understand cascading effects or community structure functioning in general, there may be a need to incorporate and understand species functional traits and how they contribute to trophic diversity, community restructuring and functioning in coastal habitats.

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15

Shah, Aliya. "Distribution of epifauna in offshore benthic environments along the west and south coast of South Africa." Master's thesis, University of Cape Town, 2018. http://hdl.handle.net/11427/29715.

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Marine unconsolidated sediments, such as sand, gravel and muds, constitute the most extensive benthic ecosystems globally. Biological data for these ecosystems are frequently sparse which can hinder the success and implementation of marine management strategies for benthic ecosystems. There are limited studies in South Africa on benthic epifauna. This study investigates the composition and distribution of epibenthic invertebrate assemblages along the west and south coast of South Africa (sampled using depth-stratified demersal trawls) to inform marine environmental management. Sample depth varied from 36m to 899m. Multivariate tools (PRIMER and PERMANOVA+) were used to analyse spatial (west vs south coast) and temporal (2011 vs 2017) patterns in epifauna. This study also investigated an overlap region between the west and south coast. A group average linkage cluster analysis defined biotopes using significant branching (p< 0.05). Biotopes were compared against the 2012 National Biodiversity Assessment (NBA) benthic habitat map to investigate whether epifaunal biotopes identified, align with the existing classification. A significant difference among epifauna between region and depth was found, where the west coast had a higher average number of individuals and species per station. Sympagarus dimorphus and Pelagia noctiluca were characteristic species for west and south coast respectively. Epifauna was found to be significantly different between 2011 and 2017, with a notable increase in the abundance of Crossaster penicillatus in 2017. The majority of the biotopes aligned with the current NBA classification, in particular the Agulhas Sandy Shelf Edge ecosystem type on the south coast and South Atlantic Upper Bathyal and Namaqua Muddy Inner Shelf ecosystem types on the west coast. This thesis contributes to the mapping and description of offshore ecosystem types to inform marine environmental impact assessments, marine spatial planning and marine protected area expansion.

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Norman, Stewart James. "Biology of Albacore tuna (Thunnus alalunga, Bonnaterre 1788) off the South West Coast of South Africa." Master's thesis, University of Cape Town, 2013. http://hdl.handle.net/11427/6632.

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Albacore tuna (Thunnus alalunga) is a highly migratory species found in all of the worlds oceans. The origin of albacore south of Africa is in question. This species constituted 85% of catches of the South African commercial tuna fishing fleet from 2000-2009 and is an important species in supporting a large boat-based recreational fishery. Albacore were sampled at angling competitions, which offer a repeatable and cheap source of tuna, in the Western Cape of South Africa during 2012 and 2013. 119 Samples were used to determine a length-weight relationship and to provide conversion ratios of various body measurements to fork length when total length was not available. Visual examination of testes and ovaries indicated that albacore are not spawning off the coast of South Africa.A comparison between the ease of using sectioned sagittal otoliths and first dorsal spines indicated that otoliths were more precise for estimating the age of albacore. Von Bertalanffy growth parameters were estimated from 51 fish, ranging from 2-9 years old (L∞=1100.07 mm; K=0.238 y-1; t₀=-2.14). Stomach content analysis indicated that the mesopelagic squid Lycoteuthis lorigera is the most important prey item for South African albacore. δ13C and δ15N stable isotope analysis of albacore and yellowfin tuna (T. albacares) muscle tissue showed that they feed on prey that may depend on different primary producers but that the two species of tuna share the same niche in the southern Benguela food web. Trophic levels of 3.8 and 3.76 were assigned to albacore and yellowfin tuna respectively.

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Frick, Jonathan. "Implementation plan for the Stellenbosch Wave Energy Converter on the South-West Coast of South Africa." Master's thesis, University of Cape Town, 2014. http://hdl.handle.net/11427/13172.

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Includes bibliographical references.
Lack of experience in wave energy conversion locally leads to uncertainty in the implementation process for the Stellenbosch Wave Energy Converter (SWEC), which is the cause of many developmental hindrances in terms of determining cost estimates, the potential site specific environmental impacts and the required permits. Cost estimates based on assumptions of capacity factor, inflation extrapolated component costs, show that with significant learning rates and reduced risk the SWEC may become cost competitive with current prices of wind and solar energy. The establishment of a full array of SWEC devices carries significant threat to coastal process, marine flora and fauna, ecosystem dynamics and functioning. Mitigation is required to be incorporated into the design and layout of the plant particularly to conserve wave energy to drive coastal processes. A considerable number of permits and permissions are required for the Development of the SWEC, with the National Environmental Management Act forming the base for the majority of permitting procedures. Complexity is added through the coastal leasing policy relying on two different Acts, and policy reform is required to encourage the uptake of wave energy conversion technologies in South Africa as current energy policy acts as a barrier to adoption. Expected environmental impacts are ranked, required permits are listed resulting in the formulation of a simple implementation plan.

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18

Sciscio, Lara. "Neogene fluvial deposits along the south-west coast of South Africa understanding the palaeoclimate through proxies." Thesis, Rhodes University, 2011. http://hdl.handle.net/10962/d1005593.

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Branched glycerol dialkyl glycerol tetraether (GDGTs) membrane lipids have been used as a new proxy for the reconstruction of terrestrial palaeoclimates. These biomarkers (or molecular ‗fossils‘) in conjunction with palynology, have been effective in the novel analysis of Miocene organic-rich sediments from three South African west coast sites at Rondeberg, Noordhoek and Langebaanweg. Lastly, a Quaternary south coast site at Rietvlei, South Africa, was also studied to further elucidate the extent of use of this new proxy. The fluvial peat and organic-rich deposits of the Elandsfontyn Formation (Sandveld Group) were investigated at Noordhoek, Langebaanweg and Rondeberg to provide new evidence for the climate and vegetation patterns during Miocene in this region. Drill-core and quarry samples from all four sites were freeze-dried, powered, and prepared for biogeochemical and palynological analyses. The methylation index of branched tetraethers (MBT) and cyclisation ratio of branched tetraethers (CBT) proxies were used to calculate the mean annual air temperature (MAAT) and pH values of the organic-rich horizons at time of deposition. The Branched versus isoprenoid index of tetraethers (BIT) was used to assess the relative contributions of marine archaeal and terrestrial bacterial tetraethers, and thereby assess the validity of the MBT, CBT and calculated palaeoenvironmental factors. The results presented in this thesis suggest that the use of the MBT/CBT proxy has significant potential in southern Africa, and may complement previously attempted palaeoclimatic and palaeoecological studies of Neogene-aged South African sediments. This type of research has the capacity to provide palaeoenvironmental information where other proxies may be absent. Results indicate that all sites yielded branched tetraether membrane lipids with the exception of Rondeberg, where GDGTs were below detection as a result of poor preservation conditions. Palynological investigation confirmed proxy derived temperatures. Furthermore palynomorph analyses supplemented earlier studies of the Noordhoek site and were piloted for the Rondeberg site, reaffirming alternating sequences of tropical and subtropical palynofloras. The MAATs, likewise, show variability and pronounced trends through time at the Langebaanweg and Noordhoek sites, generally corresponding with the variation and diversity of the pollen population. The terrestrial MAAT results appear to compliment Southern Hemisphere sea level changes associated with Antarctic glaciations. Additionally, this data shows a pattern similar to the Southern and Northern Hemisphere marine isotope records of relative fluctuations in the global climate and sea level change from the early to middle Miocene. The application of these past climate change indicators have been proved to be useful in the reconstruction of South Africa Miocene palaeoclimates, and may aid in understanding the consequences of climate change in the Cape region.

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19

Montoya-Maya, Phanor Hernando. "Dynamics of larval fish and zooplankton in selected south and west coast estuaries of South Africa." Thesis, Rhodes University, 2009. http://eprints.ru.ac.za/1641/.

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20

Ndzeng, Nyangone Emmanuel. "South Africa’s relations with Gabon and the Ivory Coast: 1969-1994." Thesis, Stellenbosch : Stellenbosch University, 2008. http://hdl.handle.net/10019.1/1138.

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Thesis (DPhil)--Stellenbosch University, 2008.
Security (war or peace), economy, technological progress, cultural development and issues of identity are some of the aspects that characterise the nature of relations between countries. Traditionally, the objectives of a country’s foreign policy concern security and welfare. But, the search for national prestige, for autonomy or for a change in the world’s power relationships or ideological re-orientation can all inform the foreign policies of many states.1 South Africa is no exception; during the stewardship of Prime Minister BJ Vorster, his objective was the launching of a policy of détente. As a consequence, South Africa was subjected to continuous external criticism. At the insistence of the discrimination apartheid policy, South Africa was excluded from a wide range of intergovernmental agencies and conferences, was isolated by the international community and became the object of an economic boycott by the vast majority of African states. It therefore was clear that the increasing hostility towards South Africa’s domestic policy would isolate the country further. The world’s reaction to South African’s domestic policy demonstrated that foreign opinion had an influence on domestic policy, and that it imposed constraints on the conduct of foreign policy. To extricate itself from this situation, South Africa initiated the policy of rapprochement called détente policy during Vorster’s time in office. Vorster had no illusions about the need for safety in South Africa, thus his main ideal as Prime Minister was to establish normal and friendly relations with African states. Vorster hoped to improve South African’s international position by improving relations with Black Africa through the policy of détente. It is with regard to this policy, undertaken during the period of the African continent’s rejection of South Africa’s race discrimination policies and this country’s exclusion from the community of African states, that the present study investigates and analyses South Africa’s relations with the Ivory Coast and Gabon from 1969 to 1994, viewed from South African and French source material. In other words, this study analyses the interaction that took place in the past with regard to the South African government’s relations with the governments of Gabon and the Ivory Coast, which directed human activities in the political, economic, military and cultural fields. This investigation and analysis were undertaken in order to understand why the Ivory Coast and Gabon became involved with South Africa when the African community and even the international community had called for the isolation of this country due to its apartheid policy, and how these relations would improve and be strengthened in the future.

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21

Burvingt, Olivier Jean-Patrick. "Storm impact and recovery along the south west coast of England." Thesis, University of Plymouth, 2018. http://hdl.handle.net/10026.1/12830.

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Extreme storms are responsible for rapid changes to coastlines worldwide. During the 2013/14 winter, the west coast of Europe experienced a sequence of large, storm-induced wave events, representing the most energetic period of waves in the last 60 years. The southwest coast of England underwent significant geomorphological change during that period, but exhibited a range of spatially variable and complex morphological responses, despite being subjected to the same storm sequence. The 2013/14 storm response along the southwest coast of England was first used as a natural field laboratory to explain the variability in storm response through the introduction and evaluation of a new classification of how sandy and gravel beaches respond to extreme storms. Cluster analysis was conducted using an unique data set of pre- and post-storm airborne Light Detection and Ranging (LiDAR) data from 157 beach sites and the calculation of volumetric beach changes and a novel parameter, the longshore variation index which quantifies the alongshore morphological variability in beach response. The method used can be applied to any sandy and gravel beaches where topographic data with sufficient spatial resolution is available. Four main beach response types were identified that ranged from large and alongshore uniform offshore sediment losses up to 170 m3 m-1 (at exposed, cross-shore dominated sites) to considerable alongshore sediment redistribution but limited net sediment change (at more sheltered sites with oblique waves). The key factors in determining the type of beach response are: exposure to the storm waves, angle of storm wave approach and the degree to which the beach is embayed. These findings provide crucial information for the development of coastal studies at regional scale, especially along coastal areas where abrupt changes in coastline orientation can be observed. A 10-year time series (2007-2017) of supra- and intertidal beach volume from exposed and cross-shore transport-dominated sites was used to examine the extent to which beach behaviour is coherent over a relatively large region (100-km stretch of coast) and predictably coupled to incident wave forcing. Over the study period, 10 beaches, exposed to similar wave/tide conditions, but having different sediment characteristics, beach lengths and degrees of embaymentisation, showed coherent and synchronous variations in sediment volumes, albeit at different magnitudes. This result is crucial for studying coastal changes in remote coastal areas or in areas where only few topographic data are available. The sequence of extreme storms of the 2013/14 winter, which represents the most erosive event over at least a decade along most of the Atlantic coast of Europe, is included in the data set, and three years after this winter, beach recovery is still on-going for some of the 10 beaches. Post-storm beach recovery was shown to be mainly controlled by post-storm winter wave conditions, while summer conditions consistently contributed to modest beach recovery. Skilful hindcasts of regional changes in beach volume were obtained using an equilibrium-type shoreline model, demonstrating that beach changes are coherently linked to changes in the offshore wave climate and are sensitive to the antecedent conditions. Furthermore, a good correlation was found between the beach volume changes and the new climate index WEPA (West Europe Pressure Anomaly), which offers new perspectives for the role and the use of climatic variations proxies to forecast coastline evolution. A process based model, XBeach, was used to model storm response at one macrotidal beach characterized by the largest sediment losses during the 2013/14 sequence of extreme storms. Beach volume changes were modelled over hypothetical scenarios with varying hydrodynamics conditions and beach states to investigate the relative roles of hydrodynamic forcing (i.e., waves and tides), beach antecedent state and beach-dune morphology in beach response to extreme storms. This modelling approach is applicable to any beach system where process based models have been implemented. Beside significant wave height and peak wave period, the beach antecedent state was shown to be the dominant factor in controlling the volumes of sediment erosion and accretion along this cross-shore dominated beach. Modelled volumes of erosion were, on average, up to three times higher along an accreted beach compared to an eroded beach for the same wave conditions. The presence of a dune, being only significantly active during spring tides and storm conditions along this macrotidal beach, was shown to reduce erosion or even cause accretion along the intertidal beach. This work provides a detailed, quantitative insight of the hydrodynamic and morphological processes involved in storm response and beach recovery on a number of spatial and temporal scales. This improved understanding of the potential impact of extreme events will hopefully aid future research efforts and ensure effective management of sedimentary coastlines.

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Reindel, Markus, and Johny A. Isla. "The Initial Period in Pernil Alto, Palpa, South Coast of Perú." Pontificia Universidad Católica del Perú, 2012. http://repositorio.pucp.edu.pe/index/handle/123456789/113332.

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Apart from the materials and archaeological contexts excavated at Hacha in the Acarí Valley, until now evidence for the Initial Period along the southern coast of Perú were limited to some isolated findings that lacked well-defined contexts, e.g. from sites like Erizo in the Ica Valley, Mastodonte in the pampa of Villacurí (Ica) and Disco Verde on the Paracas Peninsula. There were no reported findings from the Río Grande of Nasca region. Only very recently, with the development of the Nasca-Palpa Archaeological Project, were sites and evidence for the Initial Period in the Palpa Valleys encountered. These provide new insights into and new perspectives on the process of cultural development for this part of the south coast. In this paper we present and discuss the numerous finds and findings of the Initial Period that have been recovered in the excavations at Pernil Alto, which include architectural structures, ceramics and other associated materials. The analysis of these findings indicates that already in this moment in time the conditions for the stable and permanent development of the populations settling in the Río Grande drainage were given. Twenty radiocarbon dates confirm the chronological position of the contexts excavated in Pernil Alto.
Con excepción de los materiales y contextos arqueológicos excavados en el sitio de Hacha, en el valle de Acarí, las evidencias disponibles sobre el Periodo Inicial en toda la costa sur del Perú se limitan a algunos hallazgos aislados y sin contextos definidos procedentes de yacimientos como Erizo, en el valle de Ica, Mastodonte, en la pampa de Villacurí (Ica), y Disco Verde, en la península de Paracas. Los datos y materiales de la cuenca de Río Grande están ausentes hasta el momento. Solo de manera reciente, con el desarrollo del Proyecto Arqueológico Nasca-Palpa, se han registrado nuevos sitios y evidencias sobre el Periodo Inicial en los valles de Palpa, los que proporcionan una nueva perspectiva sobre el proceso de desarrollo cultural que tuvo esta parte de la costa sur. De este modo, en el presente artículo se exponen y discuten los numerosos vestigios del Periodo Inicial recuperados en las excavaciones en el sitio de Pernil Alto, los que comprenden estructuras arquitectónicas, cerámica y otros materiales asociados. El análisis de estos elementos señala que, ya en ese tiempo, se habían dado las condiciones para el desarrollo estable y permanente de las poblaciones asentadas en la cuenca de Río Grande. Veinte fechados radiocarbónicos confirman, ampliamente, la posición cronológica de los contextos excavados en este complejo.

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23

Hunter, I. T. "The Weather of the Agulhas bank and the Cape South Coast." Master's thesis, University of Cape Town, 1987. http://hdl.handle.net/11427/21858.

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Until 1982, when the National Research Institute for Oceanology (NRIO) erected self-contained, automatic weather stations (AWS) on the Cape South Coast, no continuous coastal measurements were available. This Institute had erected an AWS on the drilling rig Sedco K in 1978, so that over 3 years of very valuable off- shore data was already available on the adjacent Agulhas Bank. Al though the weather offices at George and Port Elizabeth have made accurate meteorological observations for over 30 years, this data is shown here to differ significantly from actual coastal measurements. Thus the NRIO AWS network, which operated for just over a year, provided a detailed, short-term data set for the study of coastal weather processes. In order to acquire longer term data from coastal observations, five years of hourly wind observations from lighthouse keepers along the Cape South Coast were also utilised. Although these are estimates, it is shown that a coastal estimate may be more representative of marine conditions than an anemometer reading some distance inland. Voluntary Observing Ship's data (VOS) extracted from SADCO's Marine Climatology database, provided the long-term offshore information, whilst also supplying very useful 'present weather' (synoptic code ww) observations for case studies. Observations from synoptic stations for the period that the coastal AWS were deployed (February 1982 - March 1983), were provided by the South African Weather Bureau. With this unique and comprehensive data set, the various weather systems affecting the region are discussed. Twelve case studies form the main reference for this discussion, which includes relevant oceanographic parameters. The weather systems are considered firstly as individually propagating circulations with the AWS network providing details of propagation speeds and coastwise development. Secondly the combined 'weather producing' effects of these systems are discussed, with a strong emphasis being placed on man/weather interactions. It is shown that certain operations along the Cape South Coast and over the Agulhas Bank, are extremely weather sensitive, and would benefit considerably from an increased knowledge of weather processes. Recommendations aimed not only at those managing weather sensitive operations, but also at those involved in coastal meteorological measurement and research, complete the thesis.

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Coutts-Smith, Aaron J. "The significance of mega-rips along an embayed coast." Phd thesis, School of Geosciences, 2004. http://hdl.handle.net/2123/6082.

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25

Mmonwa, Lucas Kolobe. "Phylogeography and epifauna of two intertidal seaweeds on the coast of South Africa." Thesis, Rhodes University, 2009. http://eprints.ru.ac.za/1583/.

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26

Baily, Brian. "Analysis of beach mapping techniques and their application to the investigation of the spatial and temporal variations in the morphological behaviour of the shingle beaches of southern Central England." Thesis, University of Portsmouth, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.343332.

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27

Ngejane, Zamazulu. "Seismic interpretation and 2D restoration of F-A gas field, Bredasdorp Basin south coast of South Africa." Thesis, University of the Western Cape, 2014. http://hdl.handle.net/11394/4656.

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>Magister Scientiae - MSc
Seismic interpretation is always somewhat an uncertainty and questions on whether the horizons picked are properly correlated across faults and or the structures mapped are geologically or geometrically sensible always raise a concern as it provides the principal source of subsurface information used commonly in exploration by the oil and gas industry. In this study an attempt of delineating what are or not geological features has been done by validating the seismic structural interpretation using the restoration technique which also provided information about the extensional history of the study area. The seismic data, horizon and fault interpretation have been depth converted in 2DMove software followed by a sequential restoration and decompacting workflow. Simple shear was used as the restoration algorithm based on the deformation style of the basin (extensional basin). The seismic interpretation is valid and studies on tectonics interplay in basin development (gas field scale) during the Late-Jurassic- Early Cretaceous are based on the results of the four balanced cross-sections. They indicate that the Basin is not a simple extensional rift Basin but was rather formed through an alternation of extensional and compressional phases. The area understudy has undergone extension since rifting onset (break-up of Gondwana) with two intervening minor inversion episodes further NW and SE showing no significant shortening on the central part. A maximum extension is noted within the central part of the study area along the XL_1248 thus more accommodation space and subsequently thicker sediment accumulations are encountered in this region.

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Morris, Kathryn. "Kelp forests in False Bay: urchins vs. macroalgae in South Africa's south-west coast biogeographical transition zone." Master's thesis, University of Cape Town, 2017. http://hdl.handle.net/11427/25072.

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There is ongoing global concern over unwanted regime shifts in marine systems. Shifts from diverse and productive algal-dominated ecosystems to less productive urchin and coralline-dominated temperate reefs are becoming increasingly common. Kelp forests found along South Africa's south-west coast between Cape Point and Cape Agulhas occur in a region of biogeographical overlap. They are commonly referred to as transition zone kelp forests and are dynamic ecosystems that are particularly susceptible to grazing influence from species such as sea urchins. This study (1) explores the uniformity of these transition zone kelp forests along the western side of False Bay, with a focus on macroalgae and urchins, (2) identifies a threshold in urchin density above which algal abundance declines and (3) seeks to identify relationships between attached and drift algal abundance. Twenty replicate quadrats were sampled in six kelp forests along the western side of False Bay. Within each quadrat, urchins (Parechinus angulosus) and kelps (Ecklonia maxima) were counted, percentage covers of various understorey algal species were recorded and drift algae were collected. Although there was significant variability in algal and urchin cover across the six sites, kelps generally increased from north to south, while urchins did the opposite. Urchins were negatively correlated with algal communities, and a localised threshold of 1.43kg/m² (50 urchins/m²) was identified, above which attached kelp density failed to increase above 10/m² and percentage cover of understorey algae usually remained below 20%. Surprisingly, no relationship was discovered between abundance of drift kelp and attached kelp, understorey algae or urchin density. This result was likely distorted by the naturally turbulent conditions of South African waters. Results highlight the complexity of these cool-water environments. To better understand the role of urchins in this system, experimental research into the feeding behaviour and effect of P. angulosus on kelps and understorey seaweeds in the presence/absence of drift algae is advised.

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Vat, Laura Suzanne. "The growth and reproduction of Patella granularis (Mollusca : patellogastropoda) on the south-east coast of South Africa." Thesis, Rhodes University, 2000. http://hdl.handle.net/10962/d1005388.

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Aspects of the biology and ecology of Patella granularis were investigated along a 130km stretch of the south-east coast of South Africa. Distribution, biomass, density and population structure were investigated at seven localities. In addition, a more detailed study of the growth rate and reproductive biology of populations inhabiting three different substrata (aeolianite, quartzitic sandstone and mussel shells) was conducted. The genetic relationships between these three populations was also examined, as was the foraging behaviour of the limpets inhabiting an aeolianite and a quartzitic sandstone shore. Finally, differences in food availability on the different substrata were studied. On the south-east coast, P. granularis has a wide intertidal distribution, occurring from the upper Balanoid zone through to the Cochlear zone, where it is a common inhabitant of mussel shells. The mean shell length of P. granularis was found to decrease down the shore. The largest limpets (46.6 mm shell length) were found on an offshore island in Algoa Bay. At most localities investigated, the sex ratio deviated from a 1:1 ratio with more males than females being recorded on five shores. Both limpet density and biomass were lower on the south-east coast when compared to data published for west coast populations. On the south-east coast, both density and dry biomass were highest in the lower Balanoid zone. Allozyme electrophoresis indicated that P. granularis inhabiting aeolianite, quartzitic sandstone and mussel shells are all part of a single population. Extremely high genetic identity values (0.998), low levels of heterozygosities (0.035 - 0.061), low levels of polymorphisms (25% - 31%) and low FST values (0.021) all suggest that the three populations of P. granularis form a common breeding group, despite the high levels of phenotypic plasticity observed. On all shores, P. granularis was found to grow allometrically, increasing in shell height more rapidly than shell length. Estimation of the growth rate (determined by the Von Bertalanffy growth model) of P. granularis suggested that limpets inhabiting the mussel shells grew more slowly, and attained a smaller maximum size, than those inhabiting both the aeolianite and the quartzite (K = 0.25, 0.32 and 0.33 respectively; 27.12 mm, 31.89 mm and 32.96 mm respectively). Previous work has shown that west coast P. granularis grow more quickly (K = 0.7) and reach a greater size (. 40 mm). Translocation of limpets among sites suggested that limpet size in the mussel beds was spatially constrained. Shell microgrowth bands were deposited tidally, but could not be used for aging limpets due to shell erosion. Limpets from the aeolianite had the greatest reproductive fitness, producing more eggs (.366 000/limpet) than those inhabiting quartzite (.119 500/limpet) or mussel shell limpets (.85 800/limpet). Aeolianite limpets also spawned throughout the year, whereas those from the quartzite and mussel shells spawned twice a year (once in winter and once in summer) although a great deal of interannual variability was observed. The onset of sexual maturity occurred at a similar age in all limpets (1 - 2 years) and is probably genetically entrenched. P. granularis inhabiting both an aeolianite and a quartzitic shore were active during nocturnal low tides. All limpets returned to a home scar after foraging. Whilst foraging, limpets inhabiting the aeolianite shore moved shorter distances (.17 cm) at a slower rate than those from quartzite (.30 cm). Limpets that were translocated from one substratum to the other initially moved similar distances to the source group, but after a maximum period of one week, moved distances that mirrored those moved by the resident limpets. Neither season nor tidal phase influenced the distances foraged. No directionality in foraging was found. Wear of radula teeth, particularly the pluricuspid tooth, was greater in limpets from the quartzite. It is hypothesised that the observed differences in life-history parameters and foraging behaviour of limpets both within the south-east coast and between the west and south-east coasts are related to food abundance. Chlorophyll-a, and hence microalgal biomass, was consistently higher on aeolianite (.2.5 times) than on both quartzite and mussel shells. Estimates of chlorophyll-a were higher (although not significantly) in winter. Previous studies determined that primary productivity is also higher along the west coast. Finally, the lack of evidence for migration of limpets from the low-shore to high-shore in south-east coast P. granularis is discussed. It is suggested that this species settles opportunistically within its physiological tolerances and responds morphologically to localised environmental conditions.

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Massey, Anthony Carl. "Holocene sea-level changes along the Channel coast of south-west England." Thesis, University of Plymouth, 2004. http://hdl.handle.net/10026.1/476.

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A Holocene relative sea-level (RSL) history for the south Devon coast is reconstructed through an analysis of twelve cores extracted from the coastal back-barrier environments of Bantham Sands, North Sands, Slapton Sands and Blackpool Sands. Foraminifera preserved in the sediments are assigned an indicative meaning based on the vertical distribution of their modem counterparts from contemporary salt marsh and mudflat environments in the Erme and Salcombe-Kingsbridge estuaries. The contemporary data provide the first inter-tidal (-2.6 to +2.6 m MTL) foraminifera-based transfer function for south-west England from which sea-level changes can be predicted with good precision (RMSEP = ±0.29 m). Sea-level index points (SLIPs) from basal facies provide the longterm (103 yr) RSL history. SLIPs derived from non-basal minerogenic and peat sequences are subject to post-depositional consolidation and a vertical correction, using the Paul and Baffas (1998) method, was therefore applied to these index points. The vertical displacement of fine minerogenic sediments ranges from <0.1 m above basal facies to >1 m at minerogenic-peat contacts, increasing to >2 m in organic peat facies. The age of each SLIP is obtained by AMS 14C dating of bulk sediment or plant material. The electrical resistivity method of geophysical survey provides additional subsurface mapping information of the back-barrier sediments, and the lithostratigraphic results support the view that a complex barrier-lagoon system existed along the south Devon coastline during the early Holocene. Almost 13 m of RSL rise occurred along the south Devon coastline ca. 9000 to 4400 cal years BP. The rate of early Holocene RSL rise is -5.4 ± 2.1 m/ka and -1.1 ± 0.2 m/ka during the mid- to late Holocene. The pattern and rate of RSL rise is similar to other sea-level curves produced for the region. Lambeck's (1993a, b, 1995) geophysical model predictions fit the data well during the early Holocene but Peltier's (1998) model is the best overall fit of the robust data used to reconstruct the early to mid- Holocene RSL history. Rates of middle to late Holocene sea-level rise are generally faster than the models predict. The area is still undergoing glacio-isostatic adjustment (GIA) equating to a coastal land subsidence of -1.16 m/ka since ca. 4400 cal years BP. The dataset increases the current Holocene SLIP database for the south-west peninsula and southern Britain by 23% and for south Devon by almost fivefold.

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García, Soto Rubén. "Paracas geoglyphs of the peruvian south coast: Cerro Lechuza and Cerro Pico." Pontificia Universidad Católica del Perú, 2015. http://repositorio.pucp.edu.pe/index/handle/123456789/113596.

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Traditionally, the manufacture of large found drawings on desert plains and hill slopes of the Peruvian south coast was at-tributed to the Nasca society. However, since the 1980s, it is known that this cultural manifestation is a tradition that wouldhave begun towards the 750 BC during the early part of the development of the Paracas culture. Paracas geoglyphs have beenreported from Pisco to the Rio Grande Basin of Nasca, particularly in the area of Palpa where the where they have identifiedmany of these geoglyphs. In this paper, we present groups of figures at Cerro Lechuza, Paracas, and Cerro Pico, Ica Valley, whichs how stylistic features of several phases of Paracas.
Tradicionalmente, la manufactura de figuras de grandes dimensiones en llanuras y laderas desérticas de la costa sur era atribuidaa la sociedad nazca (200 a.C. – 750 d.C.). Sin embargo, a partir de la década de los años 1980, se sabe que esta manifestacióncultural es una tradición que se habría iniciado hacia los 750 a.C. durante la parte temprana del desarrollo de la denominadacultura Paracas. Geoglifos paracas han sido registrados desde Pisco hasta la cuenca del Río Grande de Nasca, particularmente, enla zona de Palpa, en la que se han identificado numerosos. Aquí, presentamos grupos de figuras paracas de Cerro Lechuza, Pisco,y de Cerro Pico en el valle del río Ica, los cuales muestran rasgos estilísticos de varias fases de Paracas.

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Campher, Curnell. "Geological modeling of the offshore Orange Basin, west coast of South Africa." UWC, 2009. http://hdl.handle.net/11394/2852.

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>Magister Scientiae - MSc
Separation between the South American and African plate’s occurred along the present day Atlantic margin during the Middle to Late Jurassic leading to the formation of a passive margin along the west coast of Southern Africa. The margin then later developed into the large Orange Basin flanking the west coasts of South Africa and Namibia. The Orange Basin on the west coast of South Africa covers an area of roughly 130 000 square kilometers relevant to the 200 m isobath and has roughly one well drilled for every 4000 square kilometers. The basin has proven hydrocarbon reserves and potential for further discoveries. The study area is located within South African exploration licencing blocks 3A/4A and 3B/4B and covers a region of roughly 97 km by 150 km. The study aims at understanding the geological processes responsible for the formation of the Orange Basin with a focus on the evolution of source rock maturity. The methodology involved utilizing the Petrel software for seismic interpretation and well correlation utilising twodimensional seismic data and all the relevant well data including geological well logs, petrophysical well logs, well top data, check-shot data, borehole temperature data and geochemical well data such as Rock Eval and vitrinite reflectance data. PetroMod (IES, Version 10) was utilized to simulate the Orange Basin evolution and the affect on source rock maturity. Seismic interpretation of the Post-Hauterivian succession shows a relative thickening of the sedimentary sequence westward as the basin evolves from the early drift to complete drift phase. Results from the petroleum system modeling indicate that the Barremian - Early Aptian source rock is at present overmature and producing mostly gas in the shelf areas whereas the potential for oil are most likely present in the deep water area of the basin where Tertiary progradation has resulted in renewed petroleum generation. Petroleum system modeling results indicate that the younger Cenomanian - Turonian source rock is less mature than the older Barremian - Early Aptian source rock as indicated by a lower transformation ratio and is mainly producing oil.

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Gordon, Nuette. "The past and present limnology of the Soetendalsvlei wetlands, Agulhas coast, South Africa." Thesis, Nelson Mandela Metropolitan University, 2012. http://hdl.handle.net/10948/d1009430.

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As climatic conditions continue to change globally, there is a need to assess past environmental change in relation to changing water balance, temperature and sea-level. By understanding the extent of past environmental change, and how anthropogenic impacts have affected ecosystems, better and more accurate future predictions of change can be made. Through the use of the sedimentary record within coastal wetlands, geochemical, (organic content and stable isotopes) and biological (diatoms) proxies were utilised to determine; (i) the baseline water quality record for Soetendalsvlei, one of only a few coastal lakes in South Africa, (ii) the effect of agriculture and mouth manipulation of the Heuningnes Estuary on the microalgae ecology and (iii) the link between palaeo-salinity and trophic status on a regional basis between Soetendalsvlei and Groenvlei, situated 320 km apart. Present water quality and phytoplankton biomass and community structure were assessed for Soetendalsvlei and its associated wetlands, Voëlvlei and Waskraalsvlei to determine the current health of these systems and to obtain modern diatom analogues to be used in the palaeolimnological reconstruction of the coastal lake. Diatoms were not dominant during this study period. Chlorophytes and flagellates were the dominant phytoplankton groups throughout the different wetlands. With the exception of Voëlvlei, the wetlands were all in good health, although SRP concentrations were within the eutrophic to hypertrophic range and are cause for concern. In Voëlvlei, phytoplankton biomass was within the eutrophic range with chlorophyll a concentrations ranging between 20 – 400 ug.l-1 Cyanobacteria, a further indicator of eutrophic conditions, were dominant during the warmer summer periods. Rainfall and freshwater inflow had a significant effect on the biomass and composition of the phytoplankton and acted as a resetting mechanism for all the wetlands as water quality conditions improved thereafter. Comparisons of the water quality and phytoplankton community between the upper reaches of the Heuningnes Estuary and Soetendalsvlei, indicated that artificial breaching of the estuary mouth significantly impacted the connectivity between these two systems, with marine intrusion extending into the upper reaches, while freshwater conditions dominate in the coastal lake. Unfortunately for the palaeolimnological study diatom preservation was poor, however, geochemistry and stable isotope analyses did provide adequate evidence of marine transgression (~8000 yr BP and 4000-2000 yr BP) and regression events comparable to other South African sea-level models developed for the east and west coast. High organic matter content (i.e. higher trophic state) and estuarine POC (C4 vegetation) were associated with periods of marine regression, i.e. increased freshwater, whereas marine transgression events were associated with low organic content and marine POC and DOC. This is comparable to studies conducted in Uruguay (South America) where palaeo-salinity was related to trophic status, i.e. increased freshwater input was associated with high nutrients. Comparisons of the palaeo-record with recorded historical occurrences of droughts and floods, also provided a means of assessing the sedimentary record and to infer anthropogenic impacts after 1850 AD. Overall it can be concluded that coastal lakes of both continents in the Southern Hemisphere displayed similar trophic responses to sea-level fluctuations during the Holocene. This adds valuable information to global sea-level change models.

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Vosloo, Mathys Christiaan. "Network analysis of trophic linkages in two sub-tropical estuaries along the South-East coast of South Africa." Thesis, Nelson Mandela Metropolitan University, 2012. http://hdl.handle.net/10948/d1010966.

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Estuaries are some of the most productive yet threatened ecosystems in the world. Despite their importance they face significant threats through changes to river flow, eutrophication, rapid population growth long the caost and harvesting of natural resources. A number of international studies have been conducted investigating the structure and functioning of an array of ecosystems using ecological network analysis. Energy flow networks have been contsructed for coastal, lagoonal, intertidial and, most notably, permantently open estuaries. Despite the valualble insights contributed by these and other studies, a lack of information on the majority of estuarine ecosystems exists.

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Trassierra, Jaqueline Anne. "Environmental drivers of the composition and distribution of larval fish assemblages off the south coast of South Africa." Thesis, Rhodes University, 2019. http://hdl.handle.net/10962/68154.

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The species composition, distribution and patterns of vertical migration of larval fish assemblages were investigated in March and in September 2013 within two adjacent log spiral bays, Algoa Bay and St Francis Bay, on the south coast of South Africa. Fish larvae were collected by means of a boat towed bongo net (57 cm diameter; mesh aperture 500 μm). An onshore (2 km) and an offshore (3 km) station were each sampled twice during the daytime (06:00 – 18:00) with two horizontal tows: near the surface (0.5 m) and close to the bottom (12 m). Tows were repeated at night (18:00 – 23:00) for onshore sites. Larval catches included 16 fish families and 40 species. A multivariate analysis indicated that the species composition was significantly different between Algoa Bay and St Francis Bay, with Engraulidae, Blenniidae, Sparidae, Soleidae and Cynoglossidae making important contributions to the larval fish catch in Algoa Bay, while Blenniidae, Engraulidae, Tripterygiidae, Sparidae and Gobiesocidae contributed significantly in St Francis Bay. Differences in assemblage composition were noted between the Spring (September–October) and Autumn (March-April) months. The species composition of larval fish assemblages was related to wind speed, wave height, cloud cover, sea water temperature, depth, average current speed and direction. Wind speed, wave height, temperature and depth significantly contributed to the variation in larval fish densities. Abundances of larval fishes were greater offshore than onshore, larvae from pelagic eggs dominated catches offshore, while larvae from demersal eggs dominated onshore catches. Habitat structure strongly influenced the composition of larval fishes between the bays and abundances were significantly greater at night than during the day. Most larval fishes displayed a reverse diel vertical migration pattern and were most influenced by predators, wind speed and cloud cover. This study shows that larval fish assemblages are highly complex and patchy. Spawning mode, individual species behaviour, diel vertical migration, current structure, depth, temperature, wind speed, cloud cover and type of habitat substratum all influence larval fish composition and distribution in the nearshore waters of South Africa.

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Ndzipa, Victoria. "Synchronisation of breeding in populations of the brown mussel Perna perna on the South Coast of South Africa." Thesis, Rhodes University, 2013. http://hdl.handle.net/10962/d1007857.

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The general biology and seasonality of breeding of intertidal populations of the brown mussel Perna perna in South Africa are reasonably well known, but we have little information on variability either within or among populations. Synchronous spawning offers adaptive advantages to externally breeding animals. Firstly, it enhances fertilization rates and therefore the species' reproductive fitness. Secondly, spawning can also be timed to coincide with environmental conditions conducive to larval settlement and development. In addition, synchronisation of spawning will influence the synchrony of settlement. Synchronisation of larval settlement, in turn, has implications for popUlation biology, as highly pulsed settlement is likely to lead to density-dependant mortality of recruits and uncoupling of adult/recruit densities, while poorly synchronised settlement will not. Generally, sea temperature and food availability are considered the key factors underlying the initiation and the duration of the breeding cycle of mussels. However, there are proximate local cues that trigger the proliferation, maturation and release of gametes. In this study, the hypothesis tested is that factors that control food availability affect gonad development and so influence synchrony among populations. Much of the published work on spawning is based on observations of the presence of larvae in the plankton, or on settlement. A more reliable method correlates the sequence of gonad development throughout the year with changes in length-weight relationships, using histology. This study is also designed to investigate temporal differences in the timing of the breeding cycle between sheltered and exposed sites along the south coast of South Africa by histological analysis of the reproductive tissue (the gonad) and by dry weight/shell length regreSSIOns. To do this, these two techniques were applied to six mussel populations at three III ocalities that were separated on scales of about 10-20km. Within each locality, two study sites were .dentified. One was exposed to strong wave action and one was sheltered. A few hundred meters ;eparated these sites. The first technique used length-weight regressions as an indication of mussel ~ondition. Abrupt decreases in the dry body weight of a hypothetical standard animal were taken to indicate periods of spawning. Regressions were assessed for samples of 40 mussels taken from each site at intervals of 4 weeks over 13 months. The results were analysed using a 3-way ANCOV A, with dry weight as the dependent variable, shell length as a covariate, and site, exposure and month, as independent variables. The second approach used the more reliable and detailed method of assessing the annual reproductive cycle using histological sections of the gonad. Histological sections of gonads from thirty female mussels, sampled monthly from each site, were examined in the laboratory. Each gonad was categorized into one of six arbitrary developmental stages based on ovary morphology. Synchrony in spawning was examined by comparison of gonad developmental stages of individuals within and among populations. The data were analysed by 3-way nested ANOV A with mean gonad index for each population as the dependent variable, month as an independent variable and exposure nested in site. The results obtained from both techniques showed strong synchronisation among different popUlations, regardless of the scales at which they were separated. The data also indicated good synchrony within populations and, again among populations, regardless of the degree of exposure. The results also indicated that the gonad condition varied significantly at each site, exposure level and month. However, there were significant interactions among these three factors. This means that on a broader seasonal scale the six mussel populations were reasonably synchronised, but on finer monthly scales, there were temporal differences in duration of gametogenic events. The implication is that ovary development is cued by environmental factor(s) that operate on scales of at least 7-20 km rather than more localised events that may affect food availablity either through aggregation of food (local hydrography at different localities) or food delivery to the shore (degree of wave action at different sites.)
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Sutton, Glen Robert. "Exploitation patterns of the multi species/gear hake (Merluccius capensis and paradoxus) fishery on South Africa's southeast coast." Thesis, Rhodes University, 2000. http://hdl.handle.net/10962/d1005124.

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The motivation for this study was to examine the exploitation patterns of the M. capensis and M. paradoxus hake fisheries on the Southeast Coast, and determine the size and species of hake caught in each of the hand-line, long-line, and trawl methods. The handline hake fishery has increased substantially over the last several years and concerns are beginning to emerge about the impact this will have on the inshore resource collected on the South Coast between August 1998 and July 1999 was used to describe the hand-line method and estimate annual landings. Data on the size and species in longline catches of hake caught during 1997 were already available for this study. Size distributions in trawl catches were determined from commercial category landing data reported by catch weight and depth. The species composition in these catches determined by comparison using RV Afrikana survey data collected in the same depth regions. Location plays a significant role in determining the sizes and species of hake caught by each gear. Hand-lines catch smaller sizes on average than do long-lines, inshore trawls target mainly M. capensis while offshore trawls catch both hake species. A substantial amount of the hand-line hake caught on the South Coast is not reported. Examination of the exploitation patterns reveal that intense trawling pressure is directed at the smaller sized M. paradoxus inhabiting the depth region between 160-400-meters. Inshore trawls discard a large amount of small sized M. capensis within the 100-meter isobath. A preliminary stock assessment on the status of each hake species found that M. paradoxus appears to be over-exploited while M. capensis was in better shape. However, length-based pseudo-cohort analysis, used in this assessment, is critically reliant on having length frequency data from a steady state population in equilibrium. This limits the application of this model for management purposes and this finding is purely theoretical at this stage. Results suggest that each hake species is under a different pattern and level of exploitation and the multi-species nature of hake stocks on the South Coast should be considered in developing optimum management policies. Future work should focus on developing appropriate age/length keys so that an age-based VPA, which is more powerful than the length-based approach, can be applied towards stock assessments on the South Coast. Alternatively, length-data covering a longer period should be compiled and the equilibrium assumption further investigated so that the results from length-based models can be used with more confidence.

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Heydenrych, Aneria Janine. "'n Evaluering van sommige plantkundige faktore wat kleinwild-digthede in die Weskus Nasionale Park beinvloed." Thesis, Stellenbosch : Stellenbosch University, 1995. http://hdl.handle.net/10019.1/58692.

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Tesis (MSc) -- Stellenbosch University, 1995.
ENGLISH ABSTRACT: A map of the different plant communities in a part of the West Coast National Park (WCNP) is presented. The approach of the Zurich-Montpellier school is used for the phytosociological studies. Thirty plant communities are described and related to environmental factors. One new alliance, two sub-alliances, seventeen associations, seven sub-associations and three variations are described. It is suggested that the Willdenowio -- Diospyretum austro-africanae is raised to alliance level and the Eucleo -- lschyrolepion eleocharidis lowered to sub-alliance level. The different floristic groups in which the plant communities fell were Strandveld, Proto-fynbos, marsh, strand and ecotones between Strandveld and Fynbos. A further extensive survey was conducted in the Postberg Nature Reserve (PNR), which forms part of the West Coast National Park, to determine the possible cause of decline in small antelope numbers (duiker, grysbok and steenbok). The potential production of the vegetation of the Postberg Nature Reserve is about 561.64 kg DM/ha/yr. Rumen analyses of the small antelopes were performed in an attempt to assess the possible relationship between plants and animals. It is found that the small antelope utilizes a big spectrum of plants. Different plant communities were structurally examined and it is proved that the steenbok are bolder than the other two small antelope and are prepared to feed in areas having a lower plant density. Duiker and grysbok preferentially prefer plant communities taller than 60 cm. KEYWORDS Braun-Blanquet, community structure, distribution, Fynbos Biome, habitat, plant communities, Raphicerus campestris, Raphicerus melanotis, Strandveld, Sylvicapra grimmia.
AFRIKAANSE OPSOMMING: 'n Plantgemeenskapskaart is vir 'n deel van die Weskus Nasionale Park (WNP) opgetrek. Die Zurich-Montpellier fitososiologiese benadering is gebruik om die plantegroei te analiseer en te beskrywe. Dertig plantgemeenskappe is geklassifiseer, beskryf, gekarakteriseer en ekologies geinterpreteer. Ben nu we alliansie, twee sub-alliansies, sewentien assosiasies, sewe subassosiasies en drie variasies is beskryf. Daar is voorgestel dat die Willdenowio -- Diospyretum austro-africanae tot alliansievlak verhoog en die Eucleo -- Ischyrolepion eleocharidis na suballiansievlak verlaag word. Die verskillende floristiese groepe waarin hierdie plantgemeenskappe geval het bestaan uit Strandveld, Protofynbos, strand-, vleiland-, en ekotone tussen Strandveld en Fynbos. 'n Verdere intensiewe studie is in die Postberg Natuurreservaat (PNR), wat deel uitmaak van die Weskus Nasionale Park, ondemeem om 'n moontlike verklaring te vind vir die afname van kleinwildsoorte (duiker, grysbok en steenbok). Die produksiepotensiaal van die Postberg Natuurreservaat (PNR) is bepaal op ongeveer 561.64 kg DM/ha/jaar. Maaginhoud ontledings van die kleinwildsoorte is gebruik om 'n moontlike verhouding tussen plant en dier te bepaal. Daar is bevind dat die kleinwildsoorte 'n groot spektrum van plante kan benut. Verskillende plantgemeenskappe is t.o.v. plantegroeistruktuur ondersoek en daar is bewys dat die steenbok minder skugter as die grysbok en duiker is en in oop areas, met 'n laer plantdigtheid, sal beweeg. Die duiker en grysbok verkies plantgemeenskappe wat meer as 60 cm hoog is. TREFWOORDE Braun-Blanquet, Fynbosbioom, gemeenskapstruktuur, habitat, plantgemeenskappe, Raphicerus campestris, Raphicerus melanotis, Strandveld, Sylvicapra grimmia, verspreiding.

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Secomb, Dorothy Margaret School of Social Science &amp Policy UNSW. "Retirement in Mobile and Manufactured Housing on the North Coast of New South Wales, Australia." Awarded by:University of New South Wales. School of Social Science and Policy, 2000. http://handle.unsw.edu.au/1959.4/17488.

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This study considers relocatable homes as an alternative housing choice for male and female retirees fifty years of age and over. Homogeneous parks and estates planned for a specific type of relocatable home are compared with those which evolved from tourist parks and retain sites for both permanent and short-term occupancy. Four relocatable home environments are considered: caravan parks, mobile homes in mixed parks, manufactured homes in mixed parks and manufactured housing estates. The differential effects of 'age', 'house type' and 'housing environment' upon 'residential satisfaction', 'sense of community within the neighbourhood', 'social integration in the community' and 'psychological adjustment' form the analytical framework of the study. Residents of 34 parks/ estates on the North Coast of New South Wales completed 778 questionnaires. Case studies, interviews, letters and written comments provided data for qualitative analysis. Approximately 94% of respondents are satisfied with their homes and housing environments. Residential satisfaction is most influenced by the interactions and perceptions of residents; psychological adjustment is influenced by a positive attitudes towards self and one's neighbours; integration in the community is affected by levels of network. Each of these relate strongly with having a sense of community in the neighbourhood. Space internal to the dwelling relates to satisfaction, adjustment and community integration. External space relates to the need for a well planned neighbourhood which affords privacy, safety and amenities. The need for meeting places for small and large groups was recurrent. The results suggest that residents of relocatable homes tend to retain affiliation with organisations joined prior to relocation. They are not reliant on their new neighbours to integrate in their community. This result is contrary to prior research which studied site built homes and traditional neighbourhoods. The present high levels of residential satisfaction would rise if it were not for the overwhelming uncertainty of tenure and unjustifiable rises in site rent. The study reviews government policy especially in relation to tenure. A relocatable home offers no more affordability than a site-built home in the same area in the long-term but it does offer a preferred retirement lifestyle.

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Jerardino, Antonieta Mafalda Susana. "Changing social landscapes of the Western Cape coast of southern Africa over the last 4500 years." Doctoral thesis, University of Cape Town, 1996. http://hdl.handle.net/11427/21821.

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Bibliography: pages 177-205.
This thesis presents a reinterpretation of the late-Holocene hunter-gatherer archaeology of the Eland's Bay and Lambert's Bay areas of the western Cape. Marked changes in settlement, and subsistence over the last 4500 years had been previously suggested as having resulted from external factors, such as the environment and contact with incoming pastoralist groups. In contrast, this thesis presents hunter-gatherers as active role players in the transformation of their society and history. This was proposed as a result of an excavation and dating programme, palaeoenvironmental reconstructions with better resolved time sequences, and the use of an interpretative framework that emphasises possible changes in population numbers and in modes of production, as well as the consequences of these processes. Between 3500 and 2000 BP, population densities increased and residence permanence became more sedentary, both of which were easily accommodated by a productive environment. Solutions to social stress, resulting from landscape infilling, were not sought through migration, but through the formalization of ritual gatherings at Steenbokfontein Cave. During these gregarious occasions, proper codes of conducts were reinforced, inter- and intra-group conflict was mediated and peoples' identity with the local landscape was also asserted. Coinciding with the increase in population numbers after 3500 BP, subsistence was reorganized around the intensive collection of highly predictable and productive species, such as shellfish, tortoises and plants. Frequent snaring of small and territorial bovids almost completely replaced the hunting of large mobile game. A system of delayed returns was also central to coastal hunter-gatherer economy between 3000 and 2000 BP, whereby the collection, processing and storage of large quantities of shellfish meat was undertaken. The large-scale effort of this activity is attested by the massive build up of large shell middens termed "megamiddens". It seems likely that hunter- gatherers at this time obtained most of the necessary protein from marine resources. In addition to the pervasive and high levels of social stress, ecological stress became palpable as environmental conditions began to deteriorate after 2400 BP. Ritual intensification no longer provided a solution, and aggregation phases at Steenbokfontein Cave came to an end. Social networks amongst hunter-gatherer groups broke down as a consequence of their fission into smaller social units and withdrawal of some of them to the periphery of the study area. The arrival of stock-owning groups around 2000 BP triggered a series of different responses by hunter-gatherers. These varied from cooperative behaviour, assimilation, avoidance and/or conflict. It is argued that these differences were shaped to a large extent by variable socio- economic configurations amongst pre-contact hunter-gatherer groups. The diet of the newly reconfigured and diverse hunter-gatherer society became overall more mixed after 2000 BP. Shellfish gathering became less important, some hunting of large game was practiced, with most of the diet provided by plant collection, snaring of small antelopes and the capture of tortoises.

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Harrison, Trevor D. "Ecology of the ichthyofauna in three temporarily open/closed estuaries on the Natal coast." Thesis, Rhodes University, 1994. http://hdl.handle.net/10962/d1005113.

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The ichthyofauna of three small Natal estuaries, the Mhlanga, Damba and Zotsha was sampled over a period of two years. A total of 68 kinds of fishes representing 24 families, 39 genera and 56 species were captured during this study. Forty seven kinds of fishes were recorded in the Mhlanga of which Gilchristella aestuaria,Oreochromis mossambicus, Valamugil cunnesius, Valamugil sp. and juvenile mugilids numerically dominated. In terms of biomass, O. mossambicus, V. cunnesius, Liza alata, Myxus capensis and Mugil cephalus dominated the ichthyofauna of the Mhlanga. In the Damba, 24 kinds of fishes were recorded. The most abundant fishes captured were Glossogobius callidus, M. capensis and O. mossambicus. M. capensis, M. cephalus, O. mossambicus and G. callidus dominated the fish biomass captured in the Damba. A total of 56 kinds of fishes were recorded in the Zotsha during this study. The ichthyofauna of the Zotsha was numerically dominated by juvenile mugilids, G. aestuaria, O. mossambicus, Rhabdosargus holubi, Terapon jarbua, Ambassis productus and G. callidus. The species which dominated the fish biomass in the Zotsha were O. mossambicus, L. alata, Valamugil robustus, Valamugil buchanani, M. capensis, M. cephalus and V. cunnesius. Classifying the species captured according to whether they were resident estuarine species, freshwater species, estuarine-dependent marine species and marine species revealed that the first three groups were all well represented in the systems. The only system in which marine species made any significant contribution to the ichthyofauna was the Zotsha. Oreochromis mossambicus was the dominant freshwater species in all three estuaries during this study. Gilchristella aestuaria and Glossogobius callidus were the principal estuarine species in the Mhlanga and the Damba respectively. Both G. aestuaria and G. callidus were the dominant estuarine species captured in the Zotsha. The principal estuarine-dependent marine fishes captured in the Mhlanga were V. cunnesius, Valamugil sp., juvenile mugilids, M. capensis, M. cephalus and L. alata. In the Damba, M. capensis and M. cephalus were the dominant estuarine-dependent marine species and in the Zotsha juvenile mugilids, R. holubi, T. jarbua, A . productus, M. capensis, V. cunnesius, V. robustus, M. cephalus and L. alata predominated. The results of this study indicate that the estuaries are dominated at different periods by different assemblages of fishes. This is linked to the spawning and migration patterns of the various species as well as the hydrological regime of each estuary. During the winter these systems are normally closed with relatively deep waters and high food resource and habitat availability. Freshwater and estuarine species mainly inhabit the upper reaches of the systems while estuarine-dependent marine species mainly occupy the middle and lower reaches and dominate the fish community. When these systems open with the onset of the spring/summer rains, adult and sub-adult estuarine-dependent marine species emigrate to the marine environment and juveniles begin recruiting into the systems. Spring is also the peak breeding period of resident estuarine and freshwater species, resulting in an increase in the contribution of these fishes to the overall population during this period. When closed estuaries open many of them drain and this results in the fishes concentrating in the lower reaches of the system where moderate water depths are present, thus further contributing to an increase in the proportion of freshwater and estuarine species in this region. The breaching of closed estuaries also results in a slump in food resources and habitat availability. Competition and possible increased vulnerability to avian predation (due to the shallow nature of the systems), may contribute to a decrease in the proportion of estuarine and freshwater species in summer. The prolonged spawning and recruitment of 0+ juveniles of estuarine-dependent marine species results in an increase in the proportion of these fishes present in the estuaries during summer. In autumn, these systems normally close, water levels rise and available food resources and habitat increase. This allows the redistribution of freshwater and estuarine species upstream, leaving estuarine-dependent marine species to dominate the middle and lower reaches. Although temporarily open/closed estuaries along the Natal coast may not be as diverse as permanently open estuaries in terms of their ichthyofauna, their importance must not be underestimated since by providing a continuous sequence of sheltered habitats along the coast they may contribute significantly to the viability of estuarine-dependent marine fish stocks.

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Conry, Danielle Shanè. "Population status and habitat use of Indian Ocean humpback dolphins (sousa plumbea) along the south coast of South Africa." Thesis, Nelson Mandela Metropolitan University, 2017. http://hdl.handle.net/10948/15556.

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Long-lived, top-level predators, such as some marine mammals, serve as important indicators of ecosystem health. Assessing the abundance and habitat use of such marine top predators is essential for the formulation of effective conservation and management actions. There is considerable concern over the viability of small humpback dolphin opulations across a global scale and a number of studies have raised concerns over their vulnerability to extinction. In light of the recent uplisting of Indian Ocean humpback dolphins (Sousa plumbea) to ‘Endangered’ on the South African Red Data list, there is an urgent need for a greater understanding of the abundance and spatial distribution of this species along the South African coastline. Using small vessels as survey platforms between March 2014 and June 2015, this study attempted to determine the abundance, spatial distribution and habitat preferences of Indian Ocean humpback dolphins along 150 km of South Africa’s south coast. A further aim was to assess the utilisation of the current Marine Protected Area network by humpback dolphins along this coastline relative to areas outside of formal protection. Mark-recapture methods applied to photo-identification data produced abundance estimates of 84 individuals (95% CI: 72-115) within the study area for both open and closed models. An average group size of 3.94 individuals (range 1-12; SD = ± 2.82) was observed during the study, indicating a decrease in average group size of ~45 % from a previous assessment in 2002/03. Such a decline in group size could potentially be a result of a change in social structure in response to reduced prey availability. Spatial analyses of humpback dolphin geographic positions, using a kernel density estimator (KDE) and effort-weighted density grid analyses, indicate that the species is unevenly distributed over the coastal zone within the area. Sightings occurred at the highest densities within Buffels Bay and along Goukamma MPA, followed by Plettenberg Bay, Nature’s Valley, and around the Bloukrans, Elandsbos and Groot River East mouths. Habitat preference was assessed using a standard classification-based method and the results indicate a strong preference, in particular, for Dissipative Intermediate Sandy Coast habitat, followed by Very Exposed Rocky Coast, Intermediate Sandy Coast, Estuarine Shore, Mixed Shore and Inshore Reef habitats. Areas of high humpback dolphin densities appear to be associated with these habitat types, especially with Dissipative-Intermediate Sandy Coast habitat. Humpback dolphins were sighted at relatively low densities along stretches of coastline consisting predominately of Exposed Rocky Shore habitat. Long expanses of this habitat type may limit humpback dolphin movements along the coast. The observed patterns in distribution and habitat preferences may be linked to the availability of prey and/or the avoidance of predators. Average sightings per kilometer travelled (SPUE) indicate that the utilisation of the Robberg and Tsitsikamma MPAs by humpback dolphins was low, most likely due to the low availability of sandy coastline in these areas. In contrast, the utilisation of the Goukamma MPA, which is characterised by a high availability of Dissipative-Intermediate Sandy Coast, was very high. The low population numbers and declines in average group size of Indian Ocean humpback dolphins within the study area warrant concern and call for effective conservation and management measures. In light of ever-increasing levels of anthropogenic threats to coastal areas, future research and long-term monitoring of the population is essential to broaden our knowledge of the species and to detect population trends.

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43

Kemp, Lucy Valeska. "Ancient stonewall fish traps on the south coast of South Africa : documentation, current use, ecological effects and management implications." Master's thesis, University of Cape Town, 2006. http://hdl.handle.net/11427/6485.

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Includes bibliographical references (leaves 48-54).
Ancient intertidal stonewall fish traps are found world-wide and those along the SouthAfrican south coast are the focus of my thesis. These fish traps, known locally as 'vywers', have recently enjoyed much media attention as interest increases in both South Africa's cultural heritage and its diminishing fish stocks. Two pioneering studies, by Goodwin (1946) and Avery (1975), provided the only documented knowledge of these vywers. My study aimed to locate, survey and document the main concentrations of vywers within a 300-km stretch along the south coast. A total of 43 sets of vywers was located by aerial surveys, 30 of which are only accessible through private land. This affords them some measure of protection, together with five located off reserves, but diminishes their educational and tourism value. Four sets of vywers were mapped in detail using aerial photogrammetry, a method that provided a rapid, extensive, accurate survey record in the form of geo-rectified ortho-images of these sites. The vywers are built in both exposed and sheltered environments, constructed from in situ rock material built into walls with either angular or curved shapes. These walls may occur singularly or in complexes of up to 25 traps. Vywers are prone to decimation by wave action and storm damage and so require maintenance to retain their characteristic form and associated cultural information. Tensions have, however, arisen between those who maintain and fish the vywers, and fisheries managers. Data from a questionnaire survey compared with records from the literature showed that species composition has not changed significantly in the last five decades. The fish are caught most frequently during new-moon spring-tides, especially in the winter months. The vywer fishery, currently active at only two sets of vywers, targets primarily mullet species (mostly Liza richardsonii) but infrequently enjoys 'bonanza' catches of over-exploited linefish stocks such as galjoen Dichistius capensis. It is these latter catches that concern managers, in addition to the noncompliance of fishers in terms of catch composition and size, permits and gear.

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44

Oosthuizen, Ané, Meesbah Jiwaji, and Paul Shaw. "Genetic analysis of the Octopus vulgaris population on the coast of South Africa." South African Journal of Science, 2004. http://eprints.ru.ac.za/118/1/sajsci_v100_n11_a20%5B1%5D.pdf.

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This study on Octopus vulgaris focused on the COIII gene region of mitochondrial DNA. Sequences from 21 samples from the Eastern Cape, and 14 samples from the Western Cape, were compared to determine whether different populations exist along the South African coast. A 380-bp segment of the COIII region of mtDNA was amplified using the polymerase chain reaction with specific designed primers. Phylogenetic inference was made using maximum parsimony (MP), maximum likelihood (ML), and distancebased methods. All sequences conformed to a single haplotype. Lack of variation within and between east and west coast samples precluded further population genetic analysis. The sequence obtained in this study was also compared with other sequences lodged in the Genbank database. Phylogenetically, the South African O. vulgaris is closely related to O. vulgaris from Senegal (0.67% divergence) and the Mediterranean (1.51% divergence). Within the Mediterranean group, O. vulgaris from South Africa displayed less sequence divergence from Senegalese and Mediterranean individuals than O. vulgaris from Venezuela (3.85%) and Taiwan (3.87%). These data do not, therefore, refute the hypothesis of a single O. vulgaris genetic population around the coast.

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45

Thomson, Danielle, and n/a. "Arsenic and Selected Elements in Marine Photosynthetic Organisms,South-East Coast, NSW, Australia." University of Canberra. Resource, Environmental and Heritage Sciences, 2006. http://erl.canberra.edu.au./public/adt-AUC20070521.120826.

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The cycling of arsenic in the marine photosynthetic plants and algae was examined by analysing total arsenic concentrations and arsenic species in selected marine photosynthetic organisms from the south-east coast, NSW, Australia. A range of elements required for metabolism in photosynthetic organisms were also analysed to determine if any relationship between these elements and arsenic concentrations occurred. Organisms were selected from salt marsh and mangrove ecosystems, marine inter-tidal and estuarine environments, and two species of marine phytoplankton cultured, to represent the different marine environments that primary producers inhabit. Organisms selected were compared to species within their own environment and then a comparison made between the varying ecosystems. In the salt marsh and mangrove ecosystems, the leaves of four species, the mangrove Avicennia marina, the samphire Sarcocornia quinqueflora, the seablight Suaeda australis, and the seagrass Posidonia australis were sampled from three locations from the south-east coast of NSW using nested sampling. Mean total arsenic concentrations (mean � sd) dry mass for all locations were A. marina (0.38 � 0.18 �g g-1 to 1.2 � 0.7 �g g-1), S. quinqueflora (0.13 � 0.06 �g g-1 to 0.46 � 0.22 �g g-1), S. australis (0.03 � 0.06 �g g-1 to 0.05 � 0.03 �g g-1)and P. australis (0.34 � 0.10 �g g-1 to 0.65 � 0.26 �g g-1). Arsenic concentrations were significantly different between species and locations but were consistently low compared to marine macroalgae species. Significant relationships between As and Fe concentrations for A. marina, S. quinqueflora and P. australis and negative relationship between As and Zn concentrations for S. quinqueflora could partially explain arsenic concentrations in these species. No relationship between As and P concentrations were found in this study. All terrestrial species contained predominantly inorganic arsenic in the water extractable and residue fractions with minor concentrations of DMA in the water-soluble fraction. P. australis also contained dimethylated glycerol and phosphate arsenoriboses. The presence of arsenobetaine, arsenocholine and trimethylated glycerol arsonioribose is most likely due to the presence of epiphytes on fronds on P. australis. In contrast, macroalgae contained higher total arsenic concentrations compared to marine terrestrial angiosperms. Total arsenic concentrations also varied between classes of algae: red macroalgae 4.3 �g g-1 to 24.7 �g g-1, green macroalgae 8.0 �g g-1 to 11.0 �g g-1 and blue green algae 10.4 �g g-1 and 18.4 �g g-1. No significant relations were found between As concentrations and concentrations of Fe, Co, Cu, Mn, Mo, Mg, P and Zn concentrations, elements that are required by macroalgae for photosynthesis and growth. Distinct differences between algal classes were found for the proportion of arsenic species present in the lipid and water-soluble fractions, with green algae having a higher proportion of As in lipids than red or estuarine algae. Acid hydrolysis of the lipid extract revealed DMA, glycerol arsenoribose and TMA based arsenolipids. Within water-soluble extracts, red and blue-green algae contained a greater proportion of arsenic as inorganic and simple methylated arsenic species compared to green algae, which contained predominantly glycerol arsenoribose. Arsenobetaine, arsenocholine and tetramethylarsonium was also present in water-soluble extracts but is not normally identified with macroalgae and is again likely due to the presence of attached epiphytes. Residue extracts contained predominantly inorganic arsenic, most likely associated with insoluble constituents of the cell. Mean arsenic concentrations in the green microalgae Dunaliella tertiolecta were 13.3 �g g-1 to 14.5 �g g-1, which is similar to arsenic concentrations found in green macroalgae in this study. Diatom Phaeodactylum tricornutum arsenic concentrations were 1.62 �g g-1 to 2.08 �g g-1. Varying the orthophosphate concentrations had little effect on arsenic uptake of microalgae. D. tertiolecta and P. tricornutum metabolised arsenic, forming simple methylated arsenic species and arsenic riboses. The ratio of phosphate to glycerol arsenoriboses was higher than that normally found in green macroalgae. The hydrolysed lipid fraction contained DMA arsenolipid (16-96%) with minor proportions of phosphate arsenoribose (4-23%). D. tertiolecta at f/10 phosphate concentration, however, contained glycerol arsenoribose and another arsenic lipid with similar retention as TMAO as well as DMA. The similarities between arsenic species in the water-soluble hydrolysed lipids and water-soluble extracts, especially for P. tricornutum, suggests that cells readily bind arsenic within lipids, either for membrane structure or storage, releasing arsenic species into the cytosol as degradation of lipids occurs. Inorganic arsenic was sequestered into insoluble components of the cell. Arsenic species present in D. tertiolecta at lower phosphate concentrations (f/10) were different to other phosphate concentrations (f/2, f/5), and require further investigation to determine whether this is a species-specific response as a result of phosphate deficiency. Although there are similarities in arsenic concentrations and arsenic species in marine photosynthetic organisms, it is evident that response to environmental concentrations of arsenic in uncontaminated environments is dependent on the mode of transfer from the environment, the influence of other elements in arsenic uptake and the ability of the organism to metabolise and sequester inorganic arsenic within the cell. It is not scientifically sound to generalise on arsenic metabolism in �marine plants� when species and the ecosystem in which they exist may influence the transformation of arsenic in higher marine organisms. There is no evidence to suggest that angiosperms produce AB as arsenic is mostly present as inorganic As, with little or no arsenic present in the lipids. However, marine macro- and microalgae both contain lipids with arsenic moieties that may be precursors for AB transformation. Specifically, the presence of TMA and dimethylated arsenoribose based arsenolipids both can transform to AB via intermediates previously identified in marine organisms. Further identification and characterization of As containing lipids is required.

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46

Chase, Brian. "Late Quaternary palaeoenvironments of the west coast of South Africa : the aeolian record." Thesis, University of Oxford, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.423345.

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47

Hemmingsen, Maree A. "Reduction of greywacke sediments on the Canterbury Bight Coast, South Island, New Zealand." Thesis, University of Canterbury. Geography, 2004. http://hdl.handle.net/10092/4377.

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The coastline of the Canterbury Bight between Timaru and the southern end of Kaitorete Barrier is in long term erosion. Paradoxically, alluvial cliffs and several large, braided rivers drain from the rapidly eroding Southern Alps into the Canterbury Bight, transporting indurated sandstone of the Torlesse Supergroup, or greywacke, to the coast. Catchment specific sediment yields average 1856 ± 261 t km-2yr-1 compared with the world average of 182 t km-2yr-1 and are among the highest known specific sediment yields in the world. The large sediment loads from these Canterbury rivers are comprised predominantly of fine sediments as suspended load (more than 90%), with only a small proportion of coarse bedload (less than 10%), which is reflected in the nature of the mixed sand and gravel beaches. The Canterbury coastline is apparently abundantly supplied with sediment, which is transported northward forming Kaitorete Barrier. However, since the 1950's there has been very little accumulation of sediment against Banks Peninsula at the downdrift end. Previous research suggested that sediment is lost from the beaches due to abrasion. Abrasion has been used as both a generic term and to describe a specific process of mechanical reduction. However, it is not the only process that causes sediment particle change. For this reason, the term reduction is preferred to describe the overall change to sediment particles, and abrasion is simply one process of reduction. Reduction includes both physical and chemical processes operating concurrently. This thesis examines reduction and its impact on the mixed sand and gravel beaches of the Canterbury Bight. To do this, sediments were collected from 55 field sites along the Canterbury Bight and three series of tumbler experiments were carried out in the laboratory using a concrete mixer. Series One, identified the significant variables for the study of reduction. Other studies have considered sediment particle size a significant indicator of the rate of reduction, however, results showed that larger sizes did not always have the higher reduction rates. These experiments identified other areas that required further investigation, including sediment lithology due to the variations in reduction rates between sites, shape and variations in the quality of sediment at the coast and also suggested chemical weathering was important. Series Two investigated the significance of textural mix to reduction, and results showed that textural mix was a more important indicator of loss than sediment size alone. Other influences identified as significant to the reduction of sediments included lithology, where variations of sediment particles provided some explanation for variations in reduction rates between sites. Shape was investigated, but results were inconclusive as to the significance of this variable to reduction. The dominance of shapes on Canterbury Bight beaches also showed that, unlike other mixed sediment beaches, there was no zonation across the beach profile. Series Three investigated the significance of chemical weathering. Weathered and unweathered material was compared to establish the significance of the quality of sediments to reduction. The depth of weathering rinds was found to be a significant indicator of the quality of sediments, where weathered material showed greater losses than unweathered material when tumbled. Having identified the significant variables for reduction, it was possible to develop numerical models that allowed for the application of the laboratory results in the field. A textural mix model was developed based on the textural mix of sediments. Results confirmed a high variability in reduction rates along the Canterbury Bight. A sediment transport model, calibrated to 20 years of hindcast data, was developed to establish the distance travelled by sediment within the swash zone of these mixed sand and gravel beaches. A tracer experiment made it possible to establish the actual rate of sediment transport based on the movement of the faster pebbles in a sample. By combining both the textural mix model and the sediment transport model it was possible to develop a sediment displacement model. This is a predictive model and provides an estimate of the amount of time it would take for the displacement of sediment from one section of beach to another. It works on the premise that what is not lost to reduction is moved by longshore sediment transport. Finally, the thesis suggested that there was a paradox, with large braided rivers and sediments from the alluvial cliffs providing sufficient sediment to renourish the coast, yet there is very little accumulation of sediment against Banks Peninsula. So why is the coast from Timaru to Taumutu eroding? The answer is sediment displacement, where both the processes of reduction and longshore sediment transport are moving and removing the sediments from the coastal system.

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48

Schulte, Daniel. "Kinematics of the Paparoa Metamorphic Core Complex, West Coast, South Island, New Zealand." Thesis, University of Canterbury. Geological Sciences, 2011. http://hdl.handle.net/10092/5459.

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The Paparoa Metamorphic Core Complex developed in the Mid-Cretaceous due to continental extension conditioning the crust for the eventual breakup of the Gondwana Pacific Margin, which separated Australia and New Zealand. It has two detachment systems: the top-NE-displacing Ohika Detachment at the northern end of the complex and the top-SW-displacing Pike Detachment at the southern end of the complex. The structure is rather unusual for core complexes worldwide, which are commonly characterised by a single detachment system. Few suggestions for the kinematics of the core complex development have been made so far. In this study structural-, micrographic- and fission track analyses were applied to investigate the bivergent character and to constrain the kinematics of the core complex. The new results combined with reinterpretations of previous workers’ observations reveal a detailed sequence of the core complex exhumation and the subsequent development. Knowledge about the influence and the timing of the two respective detachments is critical for understanding the structural evolution of the core complex. The syntectonic Buckland Granite plays a key role in the determination of the importance of the two detachment systems. Structural evidence shows that the Pike Detachment is responsible for most of the exhumation, while the Ohika Detachment is a mere complexity. In contrast to earlier opinions the southwestern normal fault system predates the northeastern one. The Buckland Pluton records the ceasing pervasive influence of the Pike Detachment, while activity on the Ohika Detachment had effect on the surface about ~8 Ma later. Most fission track ages are not related to the core complex stage, but reflect the younger late Cretaceous history. They show post core complex burial and renewed exhumation in two phases, which are regionally linked to the development of the adjacent Paparoa Basin and the Paparoa Coal Measures to the southwest and to the inception of seafloor spreading in the Tasman Sea in a larger context.

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Mills, Simon Richard Stead. "The ritual music of South Korea's east coast shamans : inheritance, training and performance." Thesis, SOAS, University of London, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.406536.

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50

Kemper, Jessica. "The effects of fragmentation of South Coast Renosterveld on vegetation patterns and processe." Master's thesis, University of Cape Town, 1997. http://hdl.handle.net/11427/21713.

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This thesis investigates the effects of fragmentation on vegetation patterns and processes of South Coast Renosterveld at three hierarchical levels. South Coast Renosterveld is a grassy shrubland derived from shales on the coastal forelands of the Western Cape Province, South Africa. The area forms part of the Cape Floristic Region. It occurs on fine-grained, moderately fertile soils. Thus, most South Coast Renosterveld has been replaced by agriculture. This vegetation type is particularly rich in geophytes, many of which have highly localised distributions. Almost no research has been carried out on the composition and structure of South Coast Renosterveld. However, fragmentation theory suggests that the fragmentation process iof South Coast Renosterveld would cause a loss of biodiversity. Although South Coast Renosterveld is one of the most threatened vegetation types in South Africa, only 0.8% of its area is formally conserved.

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