Includes abstract. / Includes bibliographical references. / The advent of terrestrial laser-scanners made the digital preservation of cultural heritage sites an affordable technique to produce accurate and detailed 3D-computermodel representations for any kind of 3D-objects, such as buildings, infrastructure, and even entire landscapes. However, one of the key issues with this technique is the large amount of recorded points; a problem which was even more intensified by the recent advances in laser-scanning technology, which increased the data acquisition rate from 25 thousand to 1 million points per second. The following research presents a workflow for the processing of large-volume laser-scanning data, with a special focus on the needs of the Zamani initiative. The research project, based at the University of Cape Town, spatially documents African Cultural Heritage sites and Landscapes and produces meshed 3D models, of various, historically important objects, such as fortresses, mosques, churches, castles, palaces, rock art shelters, statues, stelae and even landscapes.

This thesis provides an analysis of the discourses of nature conservation in South Africa and Driftsands provincial nature reserve from constructionist and environmental justice perspectives. At the outset I examine the theoretical framework on the social construction of nature and that of environmental justice. I then discuss the history of nature conservation in South Africa. Finally I analyse the discourse (nature conservation and local communities) surrounding the Driftsands Provincial Nature Reserve (DNR). This nature reserve is located one kilometre east of Cape Town International Airport, in the Western Cape, South Africa. My analysis of the first theoretical framework (the social construction of nature) confirms that a) the idea of nature is constructed over time; b) nature, as a concept and a phenomenon, is complex; c) nature discourses reveal, hide, and create 'truths' about nature which are accepted as being truthful yet are a question of social struggle and power politics; d) humans have amassed countless definitions of the word 'nature'. Those definitions are categorised by Castree and Braun (2001) into three groups: external, intrinsic, and universal. My analysis of the second theoretical framework (environmental justice) suggests that the idea of nature can be used constructively or negatively depending on who uses it and why. The link between both theoretical frameworks suggests that nature is bound up with agendas. Humans construct natures to pursue individual, social or political agendas. From this standpoint the focus of the thesis shifts from debating whether or not nature is socially constructed to examining what type of agendas were pursued to achieve those 'natural' constructions, and what their consequences were for local communities living in and around protected areas. In order to achieve this, I employed four interlinked analytical methods (stakeholder, discourse, critical and ideological analysis). My analysis of the case study of DNR and that of the history of nature conservation in South Africa suggests ideological similarities. First, in both cases nature conservation is inspired by external environmental views. In the colonial period of South Africa, nature conservation policies and practices were shaped by English and Afrikaner protectionist ideas and aimed also to address the demand of their naturalists, sportsmen, and explorers for hunting and exploiting wild animals. In post-apartheid South Africa, nature has been 12 constructed in protected areas according to universalised environmental views and to some extent has been proactive, meaning that it aimed to address some of the social challenges. Likewise, at DNR, nature conservation was adopted in the early 1980s by the white government to pursue political agendas. In the late 1980s nature conservation began to be influenced by universalised environmental views. Second, the ideological nexus of both discourses regarding nature and local communities suggests conformity with global environmental models. Under these models the normal course is: a) to fence local communities from protected areas or to fence protected areas from local communities, b) to maximise the boundaries of protected areas, or to minimise the settlements of local communities in protected areas, c) to regulate local communities' access to protected areas and natural resources, d) to promote persuasive concepts of ecotourism to achieve nature conservation goals through community participation, co-benefiting local communities from protected areas, co-managing protected areas with local communities, and local socio-economic development, e) to aim for the removal of the on-site communities from protected areas. The impoverishment of the DNR on-site communities has been effected by means of three ideological principles. Since 1990, DNR's on-site communities have been labouring under a state of emergency - the state of living below the flood line; the state of high level of house robbery and a worrying level of rape and child abuse. Their dispossession has led to the spaces of temporality - a state of informality and limited public services and hopelessness (there is no hope of sustaining settlements on the site). Currently, these communities are cornered between two choices. Either they voluntarily relocate their shacks into the surrounding townships or they live with the state of emergency, hopelessness and temporality. Local communities of other protected areas in South Africa have been similarly impoverished by these states of emergency, temporality and hopelessness. During the colonial period, South Africa's conservation discourses were predominantly white-based. Whites constructed the common sense among themselves that they own the land and wildlife. Constructing the idea that they are the people of the land meant also suppressing the non-white sovereignty over land and natural resources. For example, Until late in the twentieth century [South African children's literature in English] 13 usually endorsed the assumption held by whites that they had exclusive ownership of the land and wildlife' (Jenkins, 2004: 107). While whites were protecting South Africa's wildlife, they also alienated blacks from nature. It is just recently, after 1994 that, 'English-Language children's writers and translators of indigenous folktales for children have begun to explore traditional beliefs about and practices in conservation (Jenkins, 2004: 107). These statements do not state or imply that English literature on humannature discourse begun to explore the idea of harmony where indigenous people live and depend on wildlife. In South Africa, it is typical for non-white communities living in or around protected areas to be relocated voluntarily or by force from their land or their settlements, and to be denied resources they had traditionally used within protected areas. Finally, both contemporary discourses continue to be in line with various universalised conservation models. Although both discourses have evolved over time, the status quo of local communities has remained the same: impoverished by exclusion from protected areas, permitted participation in only insignificant co-management models and recipients of intangible benefits. Although the contemporary discourse on nature conservation appears to be more considerate of local communities, I suggest that it is early days for this young discourse to achieve harmony between people and nature. It is up to local and national governmental and non-governmental agencies to modify global environmental views rather than fully adopting them, in order to be more respectful and accommodating of local communities.

This multiproxy study explores the palaeoenvironmental record of two cores, H2 and H7, from the Namaqualand Mudbelt representing an arid and highly variable landscape. As bulk organic radiocarbon ages previously proved problematic, with anomalous reversals, the primary objective was to improve chronology and palaeoenvironmental reconstructions through high resolution 813C, 81SN and pollen analysis, with the aid of principal component analysis. Bulk organic radiocarbon dating of the surface sediment had previously yielded older than expected ages. New 210Pb analysis has established that these surface sediments are modem and radiocarbon ages are now recalibrated to yield an adjusted age of ±3 470 cal yr BP at the base of the more distal core, H7. Pollen spectra correlate well with stable isotopes and include recent disturbance indicators in the Succulent Karoo, Grassland, Karoo expansion, stock farming, impoundment, saltmarsh degradation and increase in domestic cereal cultivation. The proximal and distal mudbelt sites are, however, isotopically distinct, with 813C, inverse nitrogen and C/N ratios characterising H2 as more terrestrial. The excursion towards C3-rich values at around 6m depth in the proximal mudbelt suggests an increase in marine sources and C3 vegetation, while associated pollen aridity indicators implicate reduced inland flooding. This is contrasted against more humid conditions at 420 cm. Stronger upwelling occurred in near-surface distal mudbelt sediment and an influx of the Buffels River sediment flooded the region at ±3470 yr BP, indicating cooler, less arid conditions. 813C studies reveal the Lower Xobies palaeoflood deposit to be less C4-rich than expected, possibly due to sediment source, and is strikingly isotopically similar to the distal mudbelt. The palaeoenvironmental interpretation of the pollen assemblage, isotopes and chronology presents an improved understanding of the region represented in the mudbelt sediments. This corresponds well with established records of the last ±3 500 years and human induced land use change within the Orange River Catchment. Results also highlight the dynamics of the Orange River, which, combined with a highly variable climate, suggest that caution should be exercised to avoid over-interpreting the level at which environmental changes can meaningfully be reconstructed in arid landscapes, particularly those which are subject to sporadic and catastrophic flooding events.

This thesis explores the utility of the MM5 regional climate model iii product big a detailed wind climatology for South Africa in the context of wind power applications. Given the background of limited available computational resources a sophisticated temporal subsetting algorithm is developed and applied. The goal here is to allow a high resolution 18 by 18km simulation to be carried out over only 365 days of historical records (20 March 1996 until 19 March 1997), yet ensure that it is possible to construct a reasonably accurate climatology from such a short time period because it represents the most typical year available. Throughout the research the model's sensitivity towards different boundary layer and cwnulus parametrisations as well as observational and grid nudging is investigated in depth. New error metrics are specifically designed and applied based on 17 reliable lOni weather stations around the country with the specific purpose of evaluating model skill with respect to the wind patterns that are important for wind turbines. An optimal model configuration is established by using the Pleim Xiu land surface scheme coupled with the Atmospheric Convective Model for the planetary boundary layer, in addition to the Kain Fiitsch II cumulus parametrisation and observational wind nudging. The model is then integrated at 18km for the entire country and the results validated in detail. It is found that average wind speeds are within 0.2 + 0.7ms (68% confidence interval) and that the daily cycle, which constitutes the largest part of the observed variance, is predicted to within 18% + 20% of amplitude and lii of timing at coastal sites.

In arid southern Africa, many rivers are ephemeral, and surface flow occurs for less than 10% of the year. Floods, which occur erratically, recharge groundwater resources on which riverine vegetation depends. Trees and shrubs are the most common life forms along these river systems, because surface flows are too erratic for aquatic organisms to flourish. There is concern that alterations to the current water regime of ephemeral rivers will affect the distribution of riparian vegetation as trees provide valuable fodder, shade, firewood and construction material in otherwise inhospitable surroundings. Climate change, population growth and development needs all place growing pressure on these water-limited ecosystems. Careful catchment management is essential to meet human water needs without jeopardising the ecosystems. This is easier said than done however, as ephemeral river ecology and functioning are hardly understood. Their unpredictable hydrology, strong groundwater association, often remote location and the presence of large terrestrial life forms make ephemeral rivers difficult to understand and current âEnvironmental water allocationâ methods for wetter systems are unsuitable. Alternative methods are being developed, but to date they still have a strong emphasis on aquatic life forms and riparian vegetation is still insufficiently addressed. This study provides an ecophysiological perspective on the water sources and drought tolerance levels of four key riparian tree species in Southern Africa. The aim is to contribute to an improved understanding of the interrelationships between river flow, groundwater and use of water by trees. Stable Hydrogen and Oxygen isotope results show that the three key species along the Kuiseb River (Acacia erioloba, Faidherbia albida and Tamarix usneoides) do not take up any water from the regularly occurring fog events. Instead, they depend on a seasonally fluctuating mix of shallow and deep soil moisture as well as groundwater. All these water sources rely on regular recharge from floods. It suggests that reductions in flood frequency and especially in magnitude and duration will reduce groundwater recharge and affect species productivity and survival. It was investigated why A. erioloba, growing in the presence of the alien Prosopis glandulosa, show high mortality rates. The study used stable 2H, 18O and 13C isotopes, xylem pressure potentials and percentage canopy dieback to conclude that within the riparian zone, the two species depend on the same water sources and that indigenous A. erioloba are 2 significantly more water stressed when growing alongside P. glandulosa. Further inland A. erioloba is entirely groundwater dependent while P. glandulosa seasonally switches between water sources. This resource partitioning is advantageous for A. erioloba, which does not display the same levels of water stress as in the riparian zone. An investigation into the physiological structure, including wood density, xylem vessel diameters and xylem vulnerability to cavitation for all four species showed that A. erioloba was structurally the most drought tolerant. This finding corresponded well with its high survival rate in the 1980s Namib drought. In the Kalahari, however, it is still outcompeted by P. glandulosa, suggesting that the invasive species has a competitive edge over A. erioloba that goes beyond xylem structure. P. glandulosa and T. usneoides are similar in structure. F. albida is structurally the most vulnerable of the species, supporting the high mortality rates observed in the 1980âs. Water sourcing using stable Hydrogen and Oxygen isotopes, xylem structure and phenology were compared for three A. erioloba stands with access to different groundwater depths (4 m, 21 m and 56 m). The aim was to determine whether A. erioloba physiology changed proportionally to groundwater depth. Results show that A. erioloba structure and phenology do respond proportionally to groundwater depth, suggesting that A. erioloba can reach deep groundwater, but that this comes at a cost of increased water stress and reduced vitality. Ttrees depending on deep groundwater may thus be closer to a water-induced survival threshold than those growing with access to shallower groundwater. Catchment managers should carefully weigh up the benefits of new water developments relative to potential losses of this ecologically and economically important species. As the final objective and synthesis this study aimed to evaluate if any of the studied species could be used as a bioindicator for tree health in relation to water availability. T. usneoides was previously observed to be less tolerant to drought conditions than F. albida and A. erioloba, while this study has shown F. albida to be structurally the most vulnerable. Hence no bioindicator could be indentified and it is concluded that the determination of drought tolerance and the identification of one or more bioindicator species for future monitoring is a complex matter that needs to include more structural studies and field documentation during drought. 3 Ultimately the use of indicator species and investigations into water sourcing as well as drought tolerance studies should inform catchment management and be included in future assessments of environmental water requirements (EWR) methods and river health. This study concludes that several of the methods applied in this study (shoot growth measurements, percentage canopy dieback, wood density, δ2H, δ18O and δ13C stable isotopes, xylem pressure potentials and xylem vessel diameters) are worth applying in in a EWR in conjunction with groundwater and flood (volume, duration and height) measurements. This will require a shift from a traditionally aquatic outlook to one that is more inclusive of terrestrial ecology. More interdisciplinary cooperation and lateral thinking between aquatic and terrestrial ecologists is crucial, so that the frequency, magnitude, predictability and duration of floods and associated groundwater recharge are assessed in terms of water needs of woody riparian species as well as the associated terrestrial fauna.

Includes bibliographical references (leaves 130-139). / This research project attempts to determine the relative influences of climate, sea level changes and human activities during the period of sediment accumulation in the Noordhoek basin in the southwestern Cape. South Africa. The research relies on lacustrine sedimentary deposits and their compositional changes as evidence of the dynamic depositional environments from which environmental conditions are inferred. Data on spatial changes on land surfaces have also been employed to complement the sedimentary chronology from catchments beyond historic records. Assessment of the extent of human influence on the Noordhoek basin has been achieved through comparison with the pristine conditions found on the Cape Nature Reserve. Analysis of dated sediment cores from the Noordhoek valley and the Cape Peninsula Nature reserve has facilitated the reconstruction of major environmental changes for the late Pleistocene and Holocene periods. An extended record of environmental change from the longest core (LM-Core) has enabled environmental reconstruction and the determination of the relative influences of climate, sea level change and human activities on the local! environment of the basin during the late Quaternary. Sedimentological evidence from the cores reveals the long-term evolution of the wetlands as being influenced by fluctuating sea levels and climate change until the mid-Holocene. Short-term environmental processes during the late Holocene. resulting from direct anthropogenic activities such as irrational uses of the wetlands for agriculture and urbanisation are responsible for polluting and transforming the status of the wetlands. Heavy metal concentrations in sediment cores from the two Noordhoek wetlands have allowed the elucidation of recent human impacts. The vertical distribution of these metals correlates with and complements the evidence of spatial changes in land use and land cover. Metal enrichment in the modern Noordhoek wetland sediments and increased organic matter content indicates increasing anthropogenic impacts on the valley as agriculture and urbanisation increased. In comparison. there is a much lower concentration of heavy metals at Groot Rondevlei, as its catchment has been less prone to severe local disturbance such as urban development and recent agricultural activities. The absence of a tightly resolved chronology for these cores restricts the understanding of the commencement and duration of major environmental changes, which have been accounted for elsewhere in the region. This limits the opportunity for direct comparison between this and other known sites. However, the Noordhoek valley is a potential resource for longer-term Quaternary environmental study. The application of a multi-disciplinary approach and high-resolution dating are highly recommended for future research in this area.

Includes bibliographical references (leaves 106-111). / The Breede River catchment in the South Western Cape is already under pressure for its water resources due to its supporting a variety of different land uses. The predominant land use in this catchment is agriculture, which demands the majority of river water for irrigation. The Department of Water Affairs and Forestry are currently investigating the future demand for water from the river, in this respect it is important to know what effect climate change will have on the change in river flow. Self Organising Maps (SOMs) are used to identify changes in the circulation systems contributing to the rainfall of the region and from this the potential change is assessed for the Breede River flow under future climate change. It is assessed that the runoff in the Breede River is expected to change under all the models of ECHAM4, CSIRO and HadAM. The magnitude of this alteration is calculated by using the change in the SOM node frequencies between the present and the future data. This is then subtracted from the present runoff data supplied by DWAF. A source of runoff decrease in the future is agricultural irrigation. The increase in irrigation under climate change is determined by inserting future climate data into an agricultural model. Once the increased amount of water used in irrigation is determined, it is subtracted from the projected future runoff. From this it is determined whether the river will be ecologically sustainable under climate change.

No description available.

Includes abstract. / Includes bibliographical references (p. 119-144). / In the continuing quest to improve climate model predictions to meet the increasing demand for knowledge on the regional effects of global climate change, it is pertinent to increase our understanding of how the underlying processes of climate are represented in the models we use to make these predictions. Concerted efforts in model evaluations and intercomparison have provided numerous insights into various model biases which plague current state-of-the-art regional climate models (RCMs). Model evaluation and assessment is crucial to model development and understanding how physical processes are represented in models is necessary for improving model parameterizations. This thesis explored model transferability as a new approach for systematic process-based intercomparison of RCMs. It investigated an untested transferability hypothesis which states that “for non-monsoon regions experiencing weak synoptic scale forcing, the height of the cloud base is correlated with the daytime surface fluxes”. An initial transferability experiment was conducted over Cabauw, the Netherlands (51.97°N, 4.93°E) to assess the models’ skill in resolving the diurnal and seasonal cycles and to investigate the simulated connections between surface and hydrometeorological variables over a non-monsoon station. The ability of models to resolve these cycles correctly is a good metric of their predictive capabilities. The data used for the study comprises three-hourly surface observations for the period October 2002 – December 2004 from the Coordinated Enhanced Observing Period (CEOP) measuring campaigns of the Global Energy and Water Cycle Experiment (GEWEX) and three-year simulations (2002 -2004) from five RCMs (CLM, GEMLAM, MRCC, RCA3 and RSM). In simulating seasonal and diurnal cycles of CBH and surface variables, the European models (CLM and RCA3) demonstrate a clear home advantage over the North American models (GEMLAM, MRCC and RSM). Principal component analysis revealed that the models couple the cloud base height with surface fluxes as in observations and that this coupling is not sensitive to changes in wind speed. This study found that summer daytime loadings gave the strongest couplings of variables. Three major processes were identified over Cabauw. First and most dominant is the surface energy process which couples sensible and latent heat with net radiation. The second process is thermodynamic, coupling temperature and surface moisture (specific humidity), and the third is a dynamic process which couples pressure and wind speed. A model intercomparison was then carried out across the six midlatitude domains to test the validity of the Cabauw findings. In observations, CBH is well coupled with the surface fluxes over Cabauw, Bondville, Lamont and BERMS, but coupled only with temperature over Lindenberg and Tongyu. All the models (except GEMLAM) simulated a good coupling with surface fluxes at all stations. In GEMLAM, there is no coupling between CBH and surface fluxes at any station. In less homogenous domains of the study, a very slight decrease in the strength of coupling is seen in most of the models, under strong large scale forcing. This would suggest that the coupling between cloud base height and surface fluxes in the models is possibly more influenced by radiative forcing than by synoptic controls. This second study confirmed the findings at Cabauw that the simulated cloud base is correlated with surface energy fluxes and the sign of the correlations in the models is as in observations. This finding is important for the modeling community as it establishes the fact that the models are actually simulating the direction of influence of surface fluxes and possibly, soil water variability, on cloud processes.

Includes abstract. / Includes bibliographical references (p. 226-252). / Fisheries compliance theory has evolved over the past two decades in an attempt to understand the factors that influence fishers’ behaviour and to develop appropriate strategies to enhance compliance. However, much of this research, which draws on both rationalist and normative perspectives, has largely focussed on the industrial fisheries. Empirical research on the small-scale fisheries sector, therefore, has been lacking. The overall aim of this thesis has been to develop a conceptual framework for understanding and addressing small-scale fisheries compliance by drawing on experiences in South Africa. This has been achieved through a detailed investigation of two small-scale fisheries case studies, as well as a review of the small-scale fisheries sector generally. The findings from this research have emphasised the need to rethink ourunderstanding of fisheries compliance in the small-scale sector. By drawing onempirical evidence, as well as the literature review, a conceptual framework has beendeveloped that enhances existing compliance theory. This study highlights that anunderstanding of compliance behaviour first requires a critical analysis of how lawhas evolved, its history and the power dynamics that have shaped it. The conceptualframework further emphasises the need to understand compliance within a fisherysystem, acknowledging that social, economic, institutional and biophysical factors allimpact on whether or not fishers’ comply with rules and laws. By applying theconceptual framework to two case studies in South Africa, key drivers that influencefisher behaviour over time are identified and changes within the fishery system areanalysed and documented. This thesis has also contributed to fisheries compliancetheory by identifying the underlying principles that are seen as necessary to guide an alternative and more integrated approach to small-scale fisheries compliance. In addition to the principles of legitimacy and deterrence, which are incorporated into existing theories of compliance, this study emphasises that the principle of social justice is required to develop a more holistic approach to understanding and addressing small-scale fisheries compliance. By embracing these principles, it is argued that fisheries policies will shift away from a sole reliance on criminal justice to achieve compliance, to a more integrated approach that aims to sustain the fishery system as a whole.