Department of Geography and Environmental Studies

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2-D and 3-D proximal remote sensing for yield estimation in a Shiraz vineyard
(Stellenbosch : Stellenbosch University, 2020-03) Hacking, Christopher James; Poblete-Echeverria, Carlos; Poona, Nitesh; Stellenbosch University. Faculty of Arts and Social Sciences. Dept. of Geography and Environmental Studies.
ENGLISH ABSTRACT: Precision viticulture aims to minimise production input expenses through the efficient management of vineyards, yielding the desired quantity and quality, while reducing the environmental footprint associated with modern farming. Precision viticulture practices aim to manage the inherent spatial variability in vineyards. Estimating vineyard yield provides insight into this process, enabling informed managerial decisions regarding production inputs. At the same time, yield information is important to the winery, as it facilitates logistical planning for harvest. Traditional yield estimation methods are destructive by nature and require in-situ sampling, which is labour-intensive and time-consuming. Proximal remote sensing (PRS) presents a suitable alternative for estimating yielding a non-destructive manner. PRS employs terrestrial proximal sensors for data acquisition that can be combined with computer vision (CV) techniques to process and analyse the data, generating the estimated yield for the vineyard. This research intends to investigate 2-dimensional (2-D) and 3-dimensional (3-D) PRS and related CV techniques for estimating yield in a vertically shoot position (VSP) trellised Shiraz vineyard. This research is presented as two components. The first component evaluates 2-D and 3-D methodologies for estimating yielding a vineyard. Three experiments are presented at bunch-and plant-level, incorporating both laboratory and in-situ experimental conditions. Under laboratory conditions (bunch-level only), the 2-D methodology achieved an r2 of 0.889, while the 3-D methodology achieved a higher r2 of 0.950. Both methodologies demonstrate the potential of PRS and associated CV techniques for estimating yield. The in-situ plant-level results favoured the 2-D methodology (fullcanopy (FC): r2= 0.779; leaf removal (LR): r2= 0.877) over the 3-D methodology (FC: r2= 0.487; LR: r2= 0.623). The general performance of the 2-D methodology was superior, and thus implemented in the subsequent component. The two set out to determine the ideal phenological stage for estimating yield. The 2-D methodology was employed with slight improvements and multitemporal digital imagery were acquired on a weekly basis for 12 weeks; culminating in a final acquisition two days prior to harvest. This component also successfully implemented image segmentation using an unsupervised k-means clustering (KMC) technique, an improvement to the colour thresholding (CT) technique implemented in component one. The ideal phenological stage was approximately two weeks prior to harvest (final stages of berry ripening), which achieved a global (bunch-level: 50 bunches) r2of 0.790 for estimating yield. This research successfully implements 2-D and 3-D PRS and CV techniques for estimating yield in a Shiraz vineyard, and thereby accomplishes the aim of this research. The research demonstrates the suitability of the methodologies–specifically the 2-D methodology, which demonstrated superior performance (simple data acquisition and analysis with competitive results). Future research could refine the presented methodologies for operational use.
Addressing the need for improved land cover map products for policy support
(Elsevier, 2020-10) Szantoi, Zoltan; Geller, Gary N.; Tsendbazar, Nandin-Erdene; See, Linda; Griffiths, Patrick; Fritz, Steffen; Gong, Peng; Herold, Martin; Morah, Brice; Obregon, Andre
The continued increase of anthropogenic pressure on the Earth’s ecosystems is degrading the natural environment and then decreasing the services it provides to humans. The type, quantity, and quality of many of those services are directly connected to land cover, yet competing demands for land continue to drive rapid land cover change, affecting ecosystem services. Accurate and updated land cover information is thus more important than ever, however, despite its importance, the needs of many users remain only partially attended. A key underlying reason for this is that user needs vary widely, since most current products – and there are many available – are produced for a specific type of end user, for example the climate modelling community. With this in mind we focus on the need for flexible, automated processing approaches that support on-demand, customized land cover products at various scales. Although land cover processing systems are gradually evolving in this direction there is much more to do and several important challenges must be addressed, including high quality reference data for training and validation and even better access to satellite data. Here, we 1) present a generic system architecture that we suggest land cover production systems evolve towards, 2) discuss the challenges involved, and 3) propose a step forward. Flexible systems that can generate on-demand products that match users’ specific needs would fundamentally change the relationship between users and land cover products – requiring more government support to make these systems a reality.
Advances in optical earth observation for geological mapping : a Review
(CONSAS Conference, 2016) Ngcofe, Luncedo Dalithemba; Van Niekerk, Adriaan
Recent increases in the availability of earth observation (EO) data and the advances made in its processing have opened up new opportunities for earth monitoring studies. This article reviews recent advances in EO, specifically in the optical domain, and comments on their potential for geological investigations. A review of the literature revealed that much work has been done on the use of multispectral to hyperspectral EO data for geological investigations, but that relatively little emphasis has been placed on the value of high spatial resolution in geological studies. From the literature it was found that geographic object based image analysis (GEOBIA) is a relatively new paradigm in remote sensing that has been shown to reduce the intra-class spectral variability in high spatial resolution imagery, thereby increasing image classification accuracies. It has been used for many applications, but relatively little research has been done on the application of GEOBIA for geological investigations. Another finding of this review is that the power of EO data increases substantially when different types of data are used (fused) together. Data fusion seizes the advantages of the capabilities of each sensor while reducing its limitations. By its nature, GEOBIA offers the ability to fuse disparate data sources and the review concludes that more research is required on the use of GEOBIA and data fusion of high resolution EO data for geological mapping.
Advancing disaster risk management in an ecological context: the case of veldfire management in South Africa
(Stellenbosch : Stellenbosch University, 2023-03) Forsyth, Gregory Graham; De Klerk, Helen; Stellenbosch University. Faculty of Arts and Social Sciences. Dept. of Geography and Environmental Studies.
ENGLISH ABSTRACT: Worldwide vegetation fires in peri-urban and rural settings pose a major hazard to social, economic and environmental assets. In South Africa, such fires are known as veldfires and they are necessary for maintaining natural processes in the fynbos, savanna and grassland biomes. Paradoxically, despite veldfires being ecologically beneficial, they often pose a risk to people and their property. This is especially so in the wildland–urban interface where buildings are found in the proximity of flammable vegetation. South Africa’s National Veld and Forest Fire Act, No. 101 of 1998 (South Africa 1998) provides a framework for setting priorities for veldfire management including the establishment of Fire Protection Associations (FPA). It seeks to find a balance between reducing risks to human lives and livelihoods while maintaining fire regimes which look after the functioning of fire-adapted ecosystems. Risk management offers a way for implementing this legislation and the National Veldfire Risk Assessment, completed in 2010, used risk management principles to establish the relative levels of veldfire risk in each of the country’s district and local municipalities. No detailed examination has been carried out of the applicability of the National Veldfire Risk Assessment framework and accuracy of nationally-generated veldfire risk information at local scales. This research addresses the gap between the National Veldfire Risk Assessment and how implementable this is to Fire Protection Associations and, at a finer scale, the wildland-urban interface. It examined three study areas typifying different spatial scales, climates, land-use practices, fuel types and assets at risk. It provides a systematic, stepwise, replicable, scalable assessment framework for determining veldfire risk that is in line with national policy (legislation). Importantly, it involves local stakeholders, and uses sound scientific ecological knowledge and established risk management principles to develop an accessible and practical methodological “tool” to identify different categories of risks at a range of spatial scales. In determining the risk, the likelihood of veldfire occurring was established, using combinations of the vegetation type and age, with the premise that the more flammable the vegetation the more likely a veldfire will occur. Consequences were decided on by identifying the types of buildings present and categorising the social and economic impacts should veldfire damage or destroy these buildings. The results were then mapped to show where vulnerable assets in the landscape are exposed to veldfires and in so doing enabling veldfire authorities to allocate resources according to the levels of risk present. This research has developed an accessible and practical “tool” to identify different categories of risks at a range of spatial scales and confirmed the relevance, applicability and scalability of the National Veldfire Risk Assessment framework. Adopting this approach will assist fire authorities to spend available budgets more effectively with more emphasis being placed on preventing rather than merely responding to veldfires. It will also assist in prioritising risk mitigation measures to prevent the inevitable future veldfires becoming disasters.
Adverse impacts of agricultural expansion on hydrological and nutrient dynamics in a Renosterveld landscape – can natural vegetation offer solutions
(Stellenbosch : Stellenbosch University, 2023-03) De Waal, Jan; Van Niekerk, Adriaan, 1970-; Miller, J; Stellenbosch University. Faculty of Arts and Social Sciences. Dept. of Geography and Environmental Studies.
ENGLISH ABSTRACT: Agricultural systems deliver a range of products to human society including, food, fuel, textiles and pharmaceuticals. However, the global expansion of agricultural activities has resulted in several negative outcomes such as biodiversity loss, increased carbon emissions, topsoil erosion and water pollution. Thus, the degradation of natural landscapes due to agricultural transformation has resulted in a loss of ecosystem services over time by increasing habitat loss, nutrient movement, sedimentation of rivers and pesticide poisoning in non-target species. One of the most impacted landscapes in terms of agricultural transformation in South Africa is renosterveld vegetation. Lowland renosterveld is a small-leaved, evergreen shrubland found on the shale-rich, fertile soils of the south-western Cape of South Africa where it forms part of the Fynbos biome, a species-rich floral kingdom. Renosterveld typically occurs on fine-grained, clay-rich soils as opposed to the sandy, nutrient-poor soils on which fynbos is located. Agricultural expansion has resulted in the destruction of the indigenous renosterveld vegetation which now exhibits a great degree of fragmentation. This dissertation documents an investigation of the impact of agricultural expansion on the hydrological, sediment and water quality dynamics in the Overberg renosterveld landscape in theWestern Cape. An evaluation is reported of whether conservation of this threatened vegetation can allow for the delivery of ecosystem services in vegetation buffers in terms of phytoremediation of nutrient inputs from agricultural slopes. The impact of changing landuse on hydrological characteristics of the area at a landscape level is examined first, followed by a case study of the Bot River by implementing a fully differentiated hydrological model with a sediment delivery component. Results confirm that hydrology on a landscape level has been greatly impacted by changes in landuse, while modelled soil erosion from the Bot River catchment depicts an increase in soil erosion from 22 t/km2/year under natural conditions to 490 t/km2/year under 2018 landuse. A one-year monitoring programme of the river was undertaken to evaluate changing dissolved nutrient dynamics down the river’s long profile through the use of ion-chromatography and stable isotope analysis. The results of this analysis indicate that nutrient loading in the river is linked to agricultural landuses and that NO[x]-N levels in the river vary seasonally and periodically exceed water quality guidelines for aquatic ecosystems. Finally, an assessment was made of the potential for natural vegetation buffer strips to mitigate nutrient inputs from agricultural hillslopes. This was performed by an analysis of soil samples via inductively coupled plasma atomic emission spectroscopy (ICP-AES), laboratory-based testing for bio-available phosphorus, nitrate and ammonium as well as isotope ratio mass spectrometer (IRMS) testing of N and C isotopic composition in soils. Results show that N concentrations in cultivated field and renosterveld soils are impacted by fertilisation of agricultural lands. There is significantly (p <0.05) more P in cultivated fields than in renosteveld soils, while renosterveld soils have a significantly (p <0.05) higher C content than cultivated fields, thus acting as a valuable carbon sink. Renosterveld fragments are shown to remediate polluted agricultural runoff, and so provide a valuable ecosystem service in the landscape.
An ‘age-regation’ process as theoretical understanding of the gated retirement village
(SUN MeDIA Bloemfontein, 2012-04) Goldhaber, Ravit; Donaldson, Ronnie
Gating the elderly appears to be a common and inevitable part of international urban life. In our study we have used the structure-agency relationship to identify and analyse the salient elements of the process of gating. In order to emphasise the dichotomy of the process in which aging people congregate together and, simultaneously, segregate themselves from urban life, we coined the term “age-regation”. We provide a comprehensive and logically structured theoretical framework, in which the theoretical bases of the gated retirement village are discussed within two overarching constructs, namely age (identity, lifestyle) and the congregation/segregation enclave (physical, social, psychological, political, economic, mobility, racial).
Agricultural field boundary delineation using earth observation methods and multi-temporal Sentinel-2 imagery
(Stellenbosch : Stellenbosch University, 2019-12) Watkins, Barry; Van Niekerk, Adriaan; Stellenbosch University. Faculty of Arts and Social Sciences. Dept. of Geography and Environmental Studies.
ENGLISH ABSTRACT: Accurate and up-to-date agricultural monitoring systems are critical for forecasting crop yield, planning resources and assessing the impact of threats to production (such as droughts or floods). The spatial extent and location of agricultural fields greatly influence these systems. Conventional methods of delineating agricultural fields, such as in situ field surveys and manual interpretation of imagery, are costly and time-consuming and are thus not suitable in an operational context. Automated earth observation techniques offer a cost-effective alternative as they can be used to execute frequent and highly detailed investigations of large areas. However, there are currently no well-established and transferable techniques to automatically delineate agricultural field boundaries. The most promising techniques found in literature include object-based image analysis (OBIA) and edge detection algorithms. This study consequently compared and evaluated multiple OBIA approaches for delineating agricultural field boundaries with multi-temporal Sentinel-2 imagery. Two sets of experiments were carried out. The first set of experiments compared and evaluated six multi-temporal OBIA approaches with which active agricultural fields in a large irrigation scheme were delineated and identified. These approaches combined two edge enhancement algorithms (Canny and Scharr) and three image segmentation techniques (watershed, multi-threshold and multi-resolution) to create six scenarios. Results showed that the watershed segmentation scenarios outperformed the multi-threshold and multi-resolution segmentation algorithms. In addition, the Canny edge detection algorithm, in conjunction with a segmentation technique, was found to produce higher boundary accuracies than its counterpart, Scharr. In the second set of experiments the best performing scenario from the first set of experiments, namely Canny edge detection in conjunction with watershed segmentation (CEWS), was modified slightly and applied to five regions in South Africa. The purpose of this investigation was to assess the robustness (transferability) of the methodology. A standard per-pixel supervised classification was performed to serve as a benchmark against which the CEWS approach was compared. Results showed that CEWS outperformed the supervised per-pixel classification in all experiments. CEWS’ robustness in different agricultural landscapes was furthermore highlighted by its creation of closed field boundaries, independence from training data and transferability. The quantitative experiments carried out in this study lay the foundation for the implementation of an operational workflow for delineating agricultural fields with the use of multi-temporal Sentinel-2 imagery. The extracted field boundaries will likely aid agricultural monitoring systems in estimating crop yield and improve resource planning and food security assessments.
Agritourism : market segmentation profile of potential and practising agritourists
(Stellenbosch : Stellenbosch University, 2003-04) Speirs, Lindsay Justine; Van der Merwe, J. H.; Stellenbosch University. Faculty of Arts and Social Sciences. Dept. of Geography and Environmental Studies.
ENGLISH ABSTRACT: Rural tourism and agritourism are in their infant stages in South Africa. It benefits the farmer, the local community, the rural area, the tourist and the country. It is therefore a viable option but requires more research, management, planning and control for it to be successful. Many agritourism ventures are not as successful as they should be. The problem is that farmers/landowners do not research the demand for tourist products before they deliver them and do not know whom they are catering for. To stay competitive, the tourists' characteristics ought to be understood. This would provide insight into what facilities and services to supply, what resources to utilise and how to promote the agritourism destination. The aim of this study was to segment the potential and practising agritourists into different clusters, according to their preferences, and to investigate the clusters' characteristics and behaviours. The objectives were to: 1. Investigate the potential and practising agritourists' socio-economic, demographic and travel characteristics. 2. Rate all the attractions, activities and services according to their popularity. 3. Clarify the preferences of these tourists, concerning attractions and activities, by combining similar ones. 4. Divide the tourists into clusters of similar preferences. 5. Compare the socio-economic, demographic and travel characteristics of the different clusters of tourists. 6. Produce a set of guidelines for entrepreneurs/farmers/landowners, as to what tourist products they should supply or develop, and for whom, and how they should market them. This study entailed distributing questionnaires to potential and practising agritourists at shopping centres and farms involved in agritouri'swimming', 'picnicking', 'scenic drives', 'dams/lakes/pans' and 'small game' were the most popular agritourism attractions and activities. Factor analysis was used to reduce the number of variables by combining like variables (attractions) and cluster analysis was utilised to segment the respondents into five clusters of tourists with similar preferences for agritourism attractions and activities. Cross tabulation, frequencies and descriptive statistics were used to describe these different clusters. These groups of tourists were described according to their demographic, socio-economic and travel characteristics. Segmenting tourism markets and compiling profiles of the tourists within each sub-market has proved to be advantageous. Once the demands of the tourists are known, the appropriate facilities and number of facilities can be developed. Knowing who the tourists are and where to target them, will lead to better marketing, planning and promotion of the destination. Customer satisfaction will be increased, as it is known exactly who must be catered for, thereby resulting in repeat visits. The five clusters of tourists were: 'general nature tourists'; 'urban tourists'; 'hard outdoor adventure tourists'; 'visual or soft outdoor adventure tourists'; and 'agritourists'. All these tourists, except 'urban tourists', are excellent potential agritourists. The results of this study were used to compile guidelines for entrepreneurs. These guidelines could help them in deciding who to target (which clusters), what agritourism products to develop (attractions, activities and services) and how to market them (means of advertising). Appropriate accommodation types and the availability of equipment and facilities for activities also act as attractions. This study demonstrates an inexpensive method of gathering information about tourists, thereby improving marketing and planning approaches. It illustrates how the potential and practising agritourists can be divided into sub-markets. The agritourism market is a heterogeneous market and must therefore be segmented. Any entrepreneur can use the results of this market segmentation. Any future studies, similar to this one, could consist of a sample much larger. As this study was primarily based in the Western Cape, similar research should be executed in other distinct regions. It would be illuminating to see how the groups of agritourists vary according to geographical areas.
Aircraft noise management through controlled-area demarcation in South Africa : its application at Cape Town International airport
(Academy of Science for South Africa, 2005) Van der Merwe, J. H.; Von Holdt, D. S.
Aircraft noise is a growing social, technical, economic and environmental problem, especially in developing countries like South Africa. It arises from the growth in air traffic, urbanization, uncoordinated planning around airports, and open-window living that makes physical insulation an ineffective mitigating solution. Cape Town International airport is a typical South African example of the phenomenon. Air traffic volume is steadily increasing and an additional runway has been proposed for the airport's efficient operation. The changing noise pattern requires the demarcation of a 'noise-controlled area' around the airport as the planning framework that is legally prescribed to manage this type of environmental nuisance. This paper reports the application of geographic Information system (GIS) technology to define a control zone using various spatial demarcation techniques. Each alternative zone has different spatial characteristics that define and incorporate the adjacent residential communities affected as well as vulnerable land in the vicinity. An aircraft noise generation model was used to map noise intensity contours. Different spatial noise footprints for six optional demarcation criteria were used to identify affected areas around the airport. The GIS methods were then compared and evaluated to select the optimum planning approach under South African conditions.
Airport noise in South Africa – Prediction models and their effect on land-use planning
(Stellenbosch : University of Stellenbosch, 2007-12) Goldschagg, Paul; Zietsman, H. L.; University of Stellenbosch. Faculty of Arts and Social Sciences. Dept. of Geography and Environmental Studies.
The use of average energy aircraft noise contours as the sole means for guiding aircraft noise-based planning around airports is being questioned increasingly. A growing proportion of residents who live in neighbourhoods adjacent to airports are dissatisfied with the averaging procedure that is employed. In their experience of exposure to aircraft noise, particularly in the evening and at night when they are at home, the average energy aircraft noise descriptors are misleading. In order to effectively analyse the socio-spatial interaction of annoyance at and interference by aircraft noise, an alternative approach has been suggested – a supplemental noise perspective. Conventional approaches to aircraft noise land use planning based on average energy noise descriptors run the risk of being ineffectual, or even counterproductive, because they do not consider the central aspects of disturbance, namely the loudness of an event and the number of times events are heard. Consequently, an alternative measure to ameliorate the limitations of average energy noise contours is needed by which airport neighbours, the aviation industry and town planners can better understand the nature of the problem. Although supplemental noise analysis is not new, this study applies it to a South African international airport (OR Tambo) for the first time. The airport’s operations are typical of many busy airports close to large urban areas, serving domestic, regional and international routes. Reportedly, there have been few complaints about noise emanating from the airport, but when they are made they are usually about evening and night-time aircraft noise events. In the context of South Africa as a developing society in transition, where growth of urban settlements continues apace, average energy aircraft noise information must be enhanced by providing supplemental noise information. This study investigated the broad issue of land use planning around airports by employing two aircraft noise prediction models, namely the Integrated Noise Model and the Transparent Noise Information Package, to establish the various potential effects and consequences of night-time aircraft noise in noise zones demarcated according to supplemental aircraft noise information. The effects and consequences examined include annoyance, disturbance of sleep, telephone conversations, watching television and work or study, and the likelihood that people will move away to escape night-time aircraft noise. The perceptions of residents living in neighbourhoods around the airport were surveyed and the responses analysed according to noise zones classified as supplemental noise information. The results show that the airport’s neighbours are annoyed by aircraft noise and that aircraft noise interferes with normal household activities. This annoyance and interference decreases with increasing distance from the airport. Furthermore, reported annoyance and interference is greater in those areas where higher numbers of noise events are encountered, even at relatively low noise levels of 60 LAmax – something not evident from average energy noise contours. This finding strengthens the argument that it is insufficient to provide only average energy aircraft noise information when studying the impact of aircraft noise. To understand the situation more fully, supplemental noise information is essential. The study concludes with a framework constructed to apply supplemental aircraft noise information to the abatement and mitigation measures normally used to deal with aircraft noise.
'n Alternatief tot die voorsiening van plaaswerker behuising
(Stellenbosch : Stellenbosch University, 1999-12) Stoumann, Deone; Pienaar, W. P.; Stellenbosch University. Faculty of Arts and Social Sciences. Dept. of Geography & Environmental Studies.
ENGLISH SUMMARY: South Africa is undergoing a process of rapid change focusing on the improvement of the living standards of previous disadvantage communities. In this context farmworkers are identified as an important part of such previous disadvantaged groups. Farmworkers in South Africa were traditionally housed through a system of tied-housing, which has resulted in their dependency on the farmer. This system is deeply rooted in the Western Cape and has a strong paternalistic base. For the first time in South African's history there is an opportunity for farmworkers to change or reduce their dependency. The new governmental subsidy scheme as well as the Draft policy for the implementation of long term security of tenure, present farmworkers 'with the opportunity to improve their living conditions, without the traditional ties to the farmer. Against this background agri-villages are considered as an alternative to traditional farmworker housing. An agri-village is a private settlement established and managed by a legal institution that is situated within an agricultural area and where residence is restricted to bona fide farm workers and their dependants. Security of tenure can be achieved according to a lease contract or usufract because the land and home stays the property of the legal institution. The theoretical and case studies that were undertaken indicated that the concept of agri-villages is in theory a viable strategy for farmworkers to reduce dependency. However agri-villages cannot merely be developed in every region in South Africa without taking cognisance of the specific needs and characteristics of each community.
Alternative land uses to forestry in the Western Cape : a case study of La Motte plantation
(Stellenbosch : Stellenbosch University, 2003-12) Fernandes Ruiz, Ricardo; Zietsman, H. L.; Rozanov, Andrei Borisovich; Stellenbosch University. Faculty of Arts and Social Sciences. Dept. of Geography and Environmental Studies.
ENGLISH ABSTRACT: The South African government started the restructuring process of the state’s forest assets in 1998. The privatisation process includes all the assets of the South African Forestry Company (SAFCOL) and half of the former homelands’ 150 000 hectares of forest. In August 2000 SAFCOL released their “Operational Plan for Implementing Exit from Forestry in the Southem-Cape Portion of the Western Cape Region”. This plan identified only major land uses (agriculture, forestry, and conservation). A more detailed and intensive land evaluation study was required to specify land utilisation types that are tailor-made to each land unit of the study area. The main intention of this research study is to develop a more detailed evaluation process that elaborates on the land uses proposed by SAFCOL, which is site-specific in terms of the type of agricultural system to be used on specific areas, or the type of indigenous vegetation to be restored in conservation areas. La Motte plantation was taken as the case study and the SAFCOL digital database for the study area was used as the input data. The Automated Land Evaluation System (ALES) was the computer software package used to build the expert system to evaluate land according to the method presented in the FAO 1976 report. The ALES model built in this research study had 15 decision trees (one per land utilisation type) resulting in a total of 1678 branches, which relate land characteristics to severity levels of land qualities. During the computation of an evaluation ALES attempts to place each map unit into one of the four severity levels of land qualities within each landutilisation type. Physical suitability of each land unit for each land utilisation type was determined by the maximum limitation method. ALES is not a GIS and does not by itself display maps. The evaluation result matrix was exported into ArcMap for further optimisation and geographical analysis to enable the spatial representation of the results. After completion, taking into account the theoretical background, optimal terrain units were identified for the different land uses considered and the results are presented as tables and maps. Fynbos is the most suitable alternative land use for the study area followed by Pears, Sauvignon Blanc and Chardonnay vines. Pinotage, Shiraz, Cabernet Sauvignon and Cabernet Franc vines were least suitable as alternatives. The study found that the SAFCOL’s database is not sufficient to meet the requirements of a detailed site-specific land evaluation process. The polygon attribute table of the soil coverage only provided a subset of the land characteristics necessary to build and run the model. Data fields like soil form, depth, drainage, wetness, terrain type, aspect and climatic information had to be created because most of the data provided were in a non-digital form. The database was not complete and more precise data are needed to improve the system.
Analysing determinants of housing tenure A cross sectional analysis in the City of Tshwane Metropolitan
(2019-04) Maringa, Tirhani Lucky; Geyer, Herman; Stellenbosch University. Faculty of Arts and Social Sciences. Dept. of Geography and Environmental Studies
ENGLISH ABSTRACT: According to the census 2011 tenure is, divided into five categories: “Owned but not yet paid off”, “Owned and fully paid off”, “rented”,“occupied and rent free” and “tenure other”. The integral focus of the study is on owned tenure sourced with other related variables from the 2011 census data. Thus the purpose of the study was to explore spatially the critical factors that influence the distribution of owned tenure in the Tshwane Metropolitan Municipality, in order to model households’ housing career and locational mobility by household head (HH) age and population group in different income areas. The study applied a bivariate correlation, geographic weighted regression analysis in order to ascertain stages in which households attained owned tenure in relation to socio-demographic and economic variables. Ordinary Least Square (OLS) modelled spatially the varying relationships and determined homogenous groupings in terms of their randomness, the results of the study revealed that the hypothesis was true with the findings that “Owned, but not fully paid off” tenure was in large proportion at “HH age group 35 –49”. However, such tenure was also larger for the white population group at “HH age group 20 –34” compared to other groups. Unfortunately, “Owned and fully paid off” tenure contradicted the hypothesis on the basis that it was dominant and larger at HH age groups above 50. Moreover, both types of ownership were highly clustered in specific areas within the study area.
An analysis of an urban edge as urban growth management instrument : Cape Town, South Africa
(Stellenbosch : Stellenbosch University, 2019-04) Horn, Anele; Donaldson, S. E.; Stellenbosch University. Faculty of Arts and Social Sciences. Dept. of Geography & Environmental Studies.
ENGLISH ABSTRACT: The City of Cape Town (CoCT) has since the 1990s employed an urban edge line and development edges policy as growth management instruments in its spatial development framework (SDF) (CoCT 2011). However, in the most recent Cape Town Spatial Development Framework (CTSDF) of 2017 they no longer make use of an urban edge line or policy as an instrument to contain horizontal urban spatial growth. Instead, the latest CTSDF champions development that will support transit‐oriented development in the urban core and notes the city’s intention not to extend services towards the urban periphery in the short‐term (CoCT 2017). This sees a considerable turn‐around from the stated historic apprehension to persistent growth pressure to the northern and eastern urban extremities of the metropolitan area by using an urban edge, and seems to suggest that the former urban edge policy was considered inappropriate or problematic to the CoCTs objectives for spatial development in the latest SDF. Reasons for the termination of this policy‐approach formed the basis of this research in which, firstly, the spatial outcomes of the urban edge line and policy in Cape Town since 2001 was evaluated by using an urban sprawl index (USI); and secondly, the decision‐making processes associated with urban development proposals contravening the urban edge line and leading to the ultimate termination of the urban edge policy instrument were analysed by applying a five‐stream confluence model. The research results revealed disproportionate population growth compared to urban expansion over a comparable time period, suggesting that the urban edge line and policy, during its time of acting as an urban growth management instrument was successful. Evaluation of decision‐making processes revealed consistent poorly motivated political decisions contravening the urban edge line and development edges policy, in favour of a neoliberal growth agenda, thereby strongly suggesting a neoliberal capture of the decision‐making authority.
An analysis of eco-labelled honey practices employed in the South African beekeeping industry : implications for agricultural sustainability
(Stellenbosch : Stellenbosch University, 2021-12) Hendricks, Lindi Leela; Williams, Samantha; Stellenbosch University. Faculty of Arts and Social Sciences. Dept. of Geography and Environmental Studies.
ENGLISH SUMMARY : This thesis presents a novel area of research for agricultural sustainability in South Africa, within the field of Geography and Environmental Studies. Previous studies on eco-labels in South Africa focussed on the commercial aspects such as the consumer understanding and perceptions (Stausebach, 2016; Struwig and Adendorff, 2018) and its application in ecotourism (Pieterse, 2004), rather than the primary sector activities associated with it such as beekeeping. The application of eco-labels in viticulture for biodiversity (Bridgman, 2009) was among the only other sampled literature in the agricultural sector of South Africa, highlighting a gap for further research. Eco-labels serve as a marketing tool to consumers, based on the environmental considerations and performance of a product. For this study they were employed as a measure to determine its efficacy for agricultural sustainability in the beekeeping industry (apiculture) in South Africa. Beekeepers across the country participated in this study to share insight on their harvesting techniques. Their responses provided in the interviews and survey conducted, assisted with understanding how eco-labelled honey is implemented in the beekeeping industry in South Africa. These eco-labels included “Badger- Friendly”, “Fairtrade”, “Pure”, “Organic”, “Raw”, “Monofloral”, “Wild Honey” as well as the “Mobius Loop”. Based on a comparative analysis of the eco-label requirements as per the literature review in contrast to the results of the study, it indicated that there are some misconceptions and subsequent misuse of the eco-labels by industry role-players. The ecolabels were either not fully understood or adhered to accordingly. This highlights that further studies are warranted to raise the level of awareness for agricultural sustainability, in the hope of instituting environmental policy changes and reform to this sector.
An analysis of the continued resurfacing of illegal backyard dwellings settlements : a case study of Mbare Residential Suburb in Harare
(Stellenbosch : Stellenbosch University, 2018-03) Chirowodza, Primrose; Geyer, Herman; Stellenbosch University. Faculty of Arts and Social Sciences. Dept. of Geography & Environmental Studies.
ENGLISH ABSTRACT: The spatial growth of irregular settlements in cities of less developed countries reflects increasing disparities in the distribution of wealth and resources. 25-70% of the urban population in African countries is living in irregular settlements, squatter settlements, unauthorised land development, rooms and flats of dilapidated buildings in city centre (Lasserve & Royston 2002). Even though massive destruction operations like Murambatsvina are being carried out in these African countries to mention just a few Zimbabwe, Tanzania and Malawi. These illegal structures are still mushrooming in African countries. This study seeks to find the underlying factors behind the continued resurfacing of these illegal dwellings in Mbare Harare. The study also looked at how migration and urbanisation determine the processes and affects informality in Zimbabwean.
Analysis of the fire hazard posed by petrol stations in Stellenbosch and the extent to which planning acknowledges risk
(Stellenbosch : Stellenbosch University, 2019-04) Qonono, Kwanele; Pharoah, Robyn; Stellenbosch University. Faculty of Arts and Social Sciences. Dept. of Geography & Environmental Studies.
ENGLISH ABSTRACT: The study aimed to investigate the extent to which land-use planning in Stellenbosch, South Africa, considers the fire-risk posed by petrol stations, and the implications for public safety, as well as preparedness for large fires or explosions. In order to achieve this, the study first identified the land-use types around petrol stations in Stellenbosch, and determined the extent to which their locations comply with the international and national planning regulations. Petrol stations within a six-kilometre radius from Stellenbosch’s centre were used as study sites. Second, the study examined the risk of fires/explosions at petrol stations. Third, the study investigated Stellenbosch Municipality’s institutional preparedness to respond in an event of a fire/explosion at a petrol station. These results suggest that the siting of petrol stations does not comply with the international and national good practices, thus exposing the surrounding developments to fires and explosions. The results also suggests that land-use planning does not consider hazards created by petrol stations. In addition, while observation at petrol stations suggest the potential for major fires, Stellenbosch Municipality’s preparedness to respond to petrol station fires appears low, due to the prioritisation of more frequent events.
Analysis of traffic accidents in Gaborone, Botswana
(Stellenbosch : University of Stellenbosch, 2009-03) Pego, Maeletso; Ferreira, S. L. A.; University of Stellenbosch. Faculty of Arts and Social Sciences. Dept. of Geography and Environmental Studies.
Botswana, a developing country in southern Africa, has not been spared the proliferating scourge of traffic accidents that is sweeping across the world. After HIV/AIDS, traffic accidents are the second largest cause of unnatural deaths in Botswana. The country is losing two per cent of its GDP every year to traffic accident costs. Furthermore, road safety is one of the major challenges the country will have to overcome in order to achieve its Vision 2016. This study investigates traffic accidents in Gaborone, the capital city of Botswana, for the years 2000 and 2005. The study analyses the characteristics of traffic accidents, examines their causes, maps the spatial distribution of traffic accidents for 2000 and 2005, and outlines the countermeasures government is instituting to curb accidents. The main data on traffic accidents used was extracted from the microcomputer accidents analysis package V5.0 (MAAP 5) obtained from the Traffic Police Division. Semi-structured interviews with transport and safety officers, traffic police and other stakeholders were conducted. The interviews were mainly about what government is doing to reduce the carnage caused by traffic accidents. Existing reports were also used as data sources. Microsoft Excel and ArcGIS 9.1 packages were used to do the analyses. The road casualties of drivers/riders are concentrated in the economically active age category of 15-64 years (95% for all casualties). In particular, the casualties are very high in the 20-39 age cohort with one third and three quarters of all casualties for 2000 and 2005 respectively. In addition, driver casualties by gender for the 20-39 age cohort show a high representation of males, namely 57% and 64% for 2000 and 2005 respectively.
Ants, altitude and change in the northern Cape Floristic Region
(Blackwell publishing Ltd, 2006) Botes, A.; McGeoch, M. A.; Robertson, H. G.; Van Niekerk, Adriaan; Davids, H. P.; Chown, S. L.; 0000-0002-5631-0206
Aim: Climate-modelling exercises have demonstrated that the Cape Floristic Region is highly sensitive to climate change and will apparently lose much of its northern limits over the next few decades. Because there is little monitoring of diversity in this area, ant assemblage structure was investigated within the main vegetation types in the Greater Cederberg Biodiversity Corridor. In particular, we sought to determine how ant assemblage structure differs between the main vegetation types, how restricted ants – and in particular the major myrmecochores – are to the major vegetation types, and which environmental variables might underlie differences in the ant assemblages and in the specificity of species to particular areas. Location: Northern Cape Floristic Region, Western Cape, South Africa. Methods: Sampling was undertaken during October 2002 and March 2003 across an altitudinal gradient ranging from sea level (Lambert’s Bay) to c. 2000 m a.s.l. (Sneeukop, Cederberg) and down again to 500 m a.s.l. (Wupperthal) in the Western Cape, South Africa. Pitfall traps were used to sample ants at 17 altitudinal bands, stretching over three vegetation types (Strandveld, Mountain Fynbos and Succulent Karoo). Biotic and abiotic environmental variables were collected at each sampling site. Generalized linear models were used to determine the relationships between species richness, density, abundance and the abundance of the major myrmecochores, and the environmental variables. Redundancy analysis was used to determine the relationship between ant assemblage structure and the environmental variables. The Indicator Value Method was used to identify characteristic ant species for each vegetation type and altitudinal site. Results: Temperature explained significant proportions of the variation in species density and abundance, and, together with area and several vegetation variables, contributed significantly to the separation of the assemblages in the major vegetation types and biomes. Four major myrmecochores were identified [Anoplolepis sp. (cf. custodiens), Anoplolepis sp. (cf. steinergroeveri), Camponotus niveosetosus, Tetramorium quadrispinosum]. The abundances of the two Anoplolepis species were related to vegetation variables, while the abundance of the other two species showed opposite relationships with temperature variables. Fourteen ant species were characteristic of certain vegetation types and altitudes. Several of these species contributed to the differences between the assemblages. Main conclusions: There are likely to be substantial and complex changes to ant assemblages as climates change in the northern Cape Floristic Region. Moreover, the importance of ants for ecosystem functioning suggests that these responses are not only likely to be a response solely to vegetation changes, but might also precipitate vegetation changes. The changes that are predicted to take place in the next 50 years in the Cape Floristic Region could be substantially exacerbated by such synergistic effects, which have major implications for long-term conservation plans. Ongoing monitoring of this transect will reveal the nature and pace of the change as it unfolds.
The application of an Urban Sprawl Index : comparing towns and cities in the Western Cape Province, South Africa
(CONSAS, 2018) Horn, Anele; Van Eeden, Amanda
The incidence and effects of urban sprawl have been the subject of a great many academic research mainly as a result of the challenges posed by continued urbanisation, especially in developing countries (see inter alia Jenks, Kozak and Takkanon 2008; Mander, Brebbia and Tiezzi 2006; Jenks and Burgess 2000; and Soja 2000). South Africa witnessed a proliferation of legislation and spatial policies to limit urban sprawl and contain the physical expansion and development of urban areas during the last two decades in response to exponential post-apartheid urbanization. In 2005, the Provincial Spatial Development Framework of the Western Cape Province, South Africa stated that “an Urban Edge shall be drawn around all villages, towns and cities in the province with the primary function to contain outward growth of urban settlements” (City of Cape Town, 2009) and in parallel the Provincial Department of Environmental Affairs and Development Planning published the Western Cape Urban Edge Guideline document assisting all municipalities in the province to delineate urban edges to be included in municipal Spatial Development Frameworks (SDF) thereby illustrating intent on maintaining urban footprints that are compact and limit developments that could be considered urban sprawl. Subsequently municipal urban edges have been delineated and are presently reflected in most municipal Spatial Development Frameworks in the province. This paper presents an Urban Sprawl Index as a tool to comparatively analyse the extent of urban sprawl between cities and towns of different sizes, making use of cadastre, land use and population data over time. The Urban Sprawl Index (USI) for the Western Cape put forward by this research will enable the comparative measurement of the extent of urban sprawl proportionately between the Metropolitan and local municipalities in the province and thereby aid in understanding the impact of planning instruments such as urban edges in the context of development dynamics and pressures experienced by individual cities.

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