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.
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.
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.
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.
Application of differential person and household growth in the Gauteng city-region, 2001-2011
(Stellenbosch : Stellenbosch University, 2018-03) Iturralde, Diego; Du Plessis, Danie; Stellenbosch University. Faculty of Arts and Social Sciences. Dept. of Geography & Environmental Studies.
ENGLISH ABSTRACT: This study deals with differential person and household growth at electoral ward level for the period 2001 – 2011 for the Gauteng City-Region. From a theoretical perspective such growth at such small area level is very valuable when dealing with issues around urban growth and urbanisation and the characteristics that this brings. At a spatial level, the manifestation of growth is critical in terms of picking up changes in its structure and distribution. Differential urbanisation has been seen to take place in other parts of the world whereby growth shifts from places in the urban core to intermediate cities and even onto smaller places before the cycle repeats itself. These urban development cycles are important to take note of and to track over time in order to be able to react to changing patterns of urban growth. In this regard it is important to appreciate what drives growth and how this plays into the realm of how a region moves a process of decentralisation to one of reurbanization and the impact this has for spatial and urban planning. This study made use of the 2001 and 2011 Census harmonised to the 2011 boundaries and using the standard deviation measure within a Gaussian distribution to create six categories of growth, three either side of the mean that are divided by one and two standard deviations. The study then showed characteristics for various characteristics for different levels of person and household growth before establishing spatial trends and patterns that identified hotspots in the city-region and in the metros of Gauteng on their own as well as identifying clustering and outliers of growth for the city-region and metros alone as well. The study identified some key findings in the shape of there being a strong urban core that drives most growth in the city-region; the mining industry along the mining belt stretching from the West Rand in Westonaria all the way north up to Rustenburg in the North West province showed its own unique trends and characteristics; and finally there is a definite trend across the city-region to move away from areas with poor service delivery towards areas that provide good quality of living with quality and reliable delivery of services.
Application of machine learning in the classification of area potential for transaction forecasting using regression analysis in two regions of the Johannesburg conurbation
(Stellenbosch : Stellenbosch University, 2024-03 ) Masola, Kabelo Charles; Munch, Zahn; Stellenbosch University. Faculty of Arts and Social Sciences. Dept. of Geography and Environmental Studies.
ENGLISH ABSTRACT: The optimal placement of a retail site is the most important decision a retailer can make. The “right” location should not only meet current business needs but also have long-term growth potential. Site selection can be done through consideration of the development and economic trajectory of the surrounding area. Studies on retail site selection are limited and current techniques that exist are either biased, lack quantitative measuring capability or fail to capture local or spatial variations. This study introduces a retail site selection spatial decision support system framework that coalesces the use of Earth Observation (EO) technologies, machine learning algorithms and spatial regression for the optimal placement of a retail site. The analysis was conducted in two regions of the Johannesburg conurbation. EO and machine learning algorithms were used in the classification of an economic area index that accurately depicted regions of spatial socio-economic variability. Random forest (RF) produced a marginally more accurate classification than Support Vector Machine (SVM), which was subsequently used as one of several input variables in a regression model. Spatial regression was used to forecast bank branch transactional volumes for the evaluation of optimal retail site placement. The findings revealed that study area-specific significant factors impacted the prediction of retail bank branch transactional volumes. The spatial regression detected localised spatial variations and patterns allowing for sound statistical inferences in the site selection process. The framework introduced in this study can be used to guide informed decisionmaking for the optimal placement of retail sites.
The application of synthetic aperture radar for the detection and mapping of small-scale mining in Ghana
(Stellenbosch : Stellenbosch University, 2020-12) Denner, Maria Gabrielle; Kemp, Jaco; Stellenbosch University. Faculty of Arts and Social Sciences. Dept. of Geography and Environmental Studies.
ENGLISH ABSTRACT: Artisanal and small-scale mining (SSM) is a cause of major environmental concern in developing countries. In Ghana, SSM is a mixture of legal and illegal operations where illegal mining is referred to as “galamsey”. Earth observation techniques can assist local governments in regulating SSM activities by providing specific spatial information on the whereabouts of SSM mines. The tropical climate in Ghana, however, hinders the regular flow of useful optical imagery due to a high percentage of cloud cover for most parts of the year. Synthetic aperture radar (SAR) can overcome this limitation. The study area includes a portion of the Ofin River near the mining town of Obuasi, Ghana. The area is tropical in climate, rural and dominated by forests. This study aims to assess the accuracy and reliability of applying SAR for the detection and mapping of small-scale mining in Ghana with classification and change detection analysis. A literature review on remote sensing and image processing literature was conducted. The satellite imagery collected for the study included single-date C-band Sentinel-1, a time series of Sentinel-1 and a single-date X-band KompSAT-5 image for the SAR analysis with Sentinel-2 and Landsat-8 imagery as ground truth datasets. Classification analysis was conducted in two experiments which included the analysis of two classification schemes, i.e. multi-class-and a binary-water classification scheme. The first experiment assessed the accuracy of random forest classification applied to single-date Sentinel-1, KompSAT-5 and multi-temporally filtered Sentinel-1 databases. The second experiment was a comparison of five machine learning supervised classification methods applied to the multi-temporally filtered Sentinel-1 database. The potential of change detection on Sentinel-1 time series data was analysed in the third experiment for the detection of SSM. Image differencing was applied and two threshold methods were tested for producing the most accurate change maps.The classification with the object-based image analysis approach was successful in classifying water bodies associated with SSM. The multi-temporally filtered Sentinel-1 dataset was the most reliable with kappa coefficients at 0.65 and 0.82 for the multi-class classification scheme and binary-water classification scheme respectively. The single-date Sentinel-1 dataset has the highest overall accuracy at 90.93% for the binary water classification scheme. The KompSAT-5 dataset only achieved the lowest accuracy at an overall accuracy of 80.61% and a kappa coefficient of 0.61 for the binary-water classification scheme. The results of the change detection analysis indicated that the Sentinel-1 imagery was able to detect and map SSM. The change detection analysis also showed the potential of discerning active from abandoned mines, but this has to be further investigated.
The application of the Planning Indicators Model as a tool for measuring the success of the Metropolitan Spatial Development Framework in the Cape Metropolitan Area
(Stellenbosch : University of Stellenbosch, 2004-12) Letsie, Moipone (Moipone Amelia Mantsebo); Zietsman, H. L.; University of Stellenbosch. Faculty of Arts and Social Sciences. Dept. of Geography and Environmental Studies.
ENGLISH ABSTRACT: Recently there has been growing interest in evaluating the performance and outcomes of spatial planning policies worldwide. In response to this a research was carried out to evaluate and monitor the effectiveness of spatial planning policies in the Cape Metropolitan Area (CMA). The Planning Indicators Model (PIM), which consists of a set of twenty-six indicators, was applied to monitor and measure the extent to which the Metropolitan Spatial Development Framework (MSDF) has affected land use and physical development in the CMA. To achieve the aim of the study, the research was divided into three phases. The first phase involved a literature review, the second phase involved interviews with planning officials and lastly, the collection of different thematic datasets required to run the Planning Indicators Model. The data sets were used to monitor and display spatiotemporal variations in conformance and performance indices in the form of maps. These maps were used to identify areas where strengths can be protected and where weaknesses need to be corrected. From a set of 26 indicators used for this study only two indicators monitored conformances (Growth of informal housing townships) over the period 1993 – 1998; the others simply indicated the present conditions. This means that the rest of the indicators did not show trends. However, the data are presented in this report as a useful baseline for future conformance and performance monitoring exercises. The study also revealed that for the past twelve years the MSDF has been the subject of extensive debate within the local authorities. Also several indicators seem to overlap and need to be clearly defined, thus it is recommended that some of these indicators should be combined to avoid duplication and confusion. Generally, the PIM can assist in making the impact of spatial planning greater in the CMA.
Applications of dairy wastewater as a fertilizer to agricultural land : an environmental management perspective
(Stellenbosch : University of Stellenbosch, 2009-03) Torr, Leigh Christine; Schloms, B. H. A.; University of Stellenbosch. Faculty of Arts and Social Sciences. Dept. of Geography and Environmental Studies.
As with any form of intensive agriculture, there are potential environmental impacts associated with the management and housing of livestock on dairy farms. Within the field of dairy farming, particular focus falls to the issue of environmental degradation of water resources, as this form of pollution is currently a major environmental issue around the world. Conventional agricultural practices involving the application of chemical fertilizers to land and crops are causing environmental problems as a result of poor management practices. Dairy wastewater and manures could however be a valuable resource for agricultural producers in the form of an alternate fertilizer for their crops. Waste application as a fertilizer is more environmentally friendly than chemical fertilizers, and could drastically reduce costs for farmers, whilst alleviating storage and management problems often associated with farmyard manures (FYM). The application of organic wastes, notably livestock manures, to land has historically been important for maintaining soil fertility on farms in terms of nutrient status and organic matter levels, as well as helping to reduce soil erosion and improve waterholding capacity. The research sought to investigate the environmental and economical feasibility of using dairy wastewater and manures as an alternative form of fertilizer within agriculture in South Africa.
Applying GIS in the evaluation of landscape aesthetics
(Stellenbosch : University of Stellenbosch, 2005-04) Fourie, Rene; Van der Merwe, J. H.; University of Stellenbosch. Faculty of Arts and Social Sciences. Dept. of Geography and Environmental Studies.
Scenic beauty, or landscape aesthetics, should be regarded as a valuable resource, to be protected and enhanced in order to generate income. Current environmental impact assessment (EIA) studies do not include the evaluation of scenic beauty as a resource properly, due to the lack of effective evaluation methods. A general dilemma lies in objectively evaluating beauty. If scenic preferences can be associated consistently with the physical landscape features, the latter can be used as predictors of the former. Analysis of aesthetics can therefore be done with a degree of objectivity, based on these general preferences. A large number of these preferences are morphologically measurable. In other words, these preferences can be mapped in a Geographical Information System (GIS), rated, and evaluated quantitatively. The first step in objectively evaluating landscape aesthetics entailed identification and compilation from the literature of conceptual components in a landscape, i.e. the units defining a landscape. Four components were identified: landform, vegetation, water features and man-made features. Each of the four components can be subdivided into several elements. Secondly, scenic preferences that can be consistently associated with landscape features were identified. It was found that any subjective experience of landscape aesthetics would be either one of calmness or one of excitement. The presence or absence of the landscape elements, and specific combinations of elements and element variables within the context of an individual landscape, will determine the type and extent of the aesthetic experience of the viewer. Finally, this theory was put into practice. Coverages were created of a test region, with landscape elements as the features of the coverages, and element variables or characteristics as feature attributes. These landscape elements, as they enhance either calmness or excitement, were quantified by assigning value ratings to the elements according to the extent of the influence of the elements on the aesthetic value of the landscape. ArcInfo GRID functionality was used to convert the coverages to raster (or grid) overlays, using the element variables enhancing both calmness and excitement. A simple cumulative summing function was used to derive an aggregate Calm Aesthetic Experience map by adding grids enhancing calmness. An aggregate Exciting Aesthetic Experience map was constructed by adding grids enhancing excitement. Finally, these two grids were summed in order to construct a Total Aesthetic Experience map, which is an indication of the total aesthetic value of the test region. The outcome of this research was a method for analysis and objective evaluation of a landscape, using a GIS for data creation, analysis and map construction. The resultant map is an indication of aesthetic value, showing the test region graded according to intrinsic aesthetic value.

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