Includes abstract. / Includes bibliographical references. / This study provides insight into the barriers of adapting to urban flooding as well as how flooding is responded to in informal settlements in order to increase adaptive capacity to future climate change. There is a growing concern over the increase in extreme events expected as part of climate change.

Includes bibliographical references. / Wheat producers in the South Western Cape (SWC) of South Africa need to cope with biophysical and socio-economic systems exposing farmers to a multidimensional decision- making environment. The rain fed wheat production in the Swartland region is highly susceptible to the interannual variability of winter rainfall. Producers, therefore, need relevant climatic information to identify ways to improve profitability and to make sound economic decisions. Seasonal forecasting has the potential to provide wheat producers with invaluable information regarding the climatic conditions. However, due to the complex nature of the atmospheric dynamics associated with winter rainfall in South Africa, seasonal forecasting models have been found to have very little skill in predicting the variability of winter rainfall. Such a shortfall has created a gap for which this study has attempted to bridge. This study aimed to investigate the relationship between wheat-specific rainfall characteristics, large-scale modes of climate variability and wheat yields in the Swartland region to assess whether these relationships could provide useful climatic information to the wheat farmers. Six wheat-specific rainfall characteristics (total rainfall ; number of wet days ; number of ‘good’ rainfall events; number of heavy rainfall events; percentage ‘good’ rainfall ; and the number of dry dekads ) on various time scales (winter; seasonal; monthly and dekadal) were correlated against wheat yield records over a 17 year period from 1994 to 2010. From this analysis, the distribution and timing of the rainfall throughout the wheat growing season (April to September) emerged as an important determinant of wheat yield. An accurate statistical wheat prediction model was created using farmer stipulated rainfall- wheat yield thresholds. Three teleconnections (El Niño-Southern Oscillation [ENSO], Antarctic Oscillation [AAO] and South Atlantic sea surface temperatures [SSTs]) represented by eight climate indices (Nino 3.4 Index, Ocean Nino Index [ONI], Southern Oscillation Index [SOI], AAO index, Southern Annular Mode Index [SAM], South Atlantic Dipole Index [SADI], South Western Atlantic SST Index [SWAI] and South Central Atlantic SST Index [SCAI]), were correlated against wheat yield data over a 17 year period from 1994 to 2010. The relationships between the three teleconnections and wheat yield in the Swartland were established. Teleconnection-wheat yield correlations were found to be limited, with regards to the application of this information to farmers, due to the lack of a comprehensive understanding of the dynamics of how the three teleconnections influence the local climate and, therefore, the wheat yield in the Swartland. The eight climate indices, representing the three teleconnections, were correlated against the six wheat-specific rainfall characteristic indices from each of the three study areas over the period from 1980 to 2012. The state of ENSO during the first half of the year was shown to be correlated with rainfall characteristics during both the first (April to July) and second (July to September) halves of the wheat growing season; however, these correlations differ ed in their sign. Correlations suggested a negative phase of AAO was associated with above normal rainfall throughout the year across the Swartland region. Sea surface temperatures in the central South Atlantic during March to October showed significant negative correlations with rainfall during the latter half of the wheat growing season (July to October) across the Swartland region. This study presented evidence supporting the plausibility and validity for the use of the state of large-scale modes of variability in the prediction of wheat-specific rainfall characteristics and aggregated yields in the Swartland region. This has the potential to provide useful information to wheat farmers in the Swartland to aid in their decision making process

Future climate is projected to deviate from present-day by unprecedented measure, hereafter climate departure, with direct consequences on food security. West Africa, one of the hotspots for climate departure globally, has suffered significantly from climate change impacts via extreme events with large impacts on food production. A better understanding of the impact of climate departure on crop growth suitability and planting season is still unknown and is highly needed in West Africa, owing to its high vulnerability and low adaptive capacity. This thesis developed a methodology aimed at defining the cropping system to investigate the projected timing of climate departures from historical variability and their impact on crop growth suitability over West Africa. For the study we used 4 statistically downscaled Global Climate Models, GCMs at station level for the period 1951- 2100 under RCP8.5 across the three AgroEcological Zones (AEZs) of West Africa for eight crops, cassava, maize, mango, orange, pearl millet, plantain, pineapple and tomato. Climate variables minimum mean monthly temperature and total monthly precipitation were used as input crop suitability model, Ecocrop to develop a new approach to define and characterise cropping systems departure from their normal regime, called crop-climate departure (CCD), to better understand the timing of future changes in crop suitability. Also, the concept of CCD was defined, tested and applied in West Africa for five different crops types, using 10 GCMs downscaled by regional climate model, RCA4 as input into crop suitability model Ecocrop. The downscaled GCMs were also employed to examine the impact at the different global warming levels, 1.5, 2.0 and 3.0oC on crop suitability over West Africa. Using the GCMs at station level, we develop the concept of crop-climate used in characterizing the suitability of different crop across the three AEZs of West Africa. The result highlights the constraint, a reduction in suitable area, of growing cassava and pineapple only in the Guinea zone by mid and end of century. In contrast, there is an observed and projected opportunity, increase in suitable areas, of growing maize in southern Sahel by the end of the century while mango remains suitable across the three West African AEZs. The application applying the concept crop-climate departure on different crop types showed in decrease suitable areas for most crops by the end of century with horticultural, cassava and cereals respectively are the crops mostly affected. The changes in crop-climate relationship suggests a future constraint in crop suitability could be detrimental to future food security over West Africa. Finally, our findings from the impact of different global warming levels, 1.5. 2.0 and 3.0oC highlights the potential of sustained suitability for all the crops and improved food security under 1.5oC global warming for all the six crops but a contrast under 3oC over West Africa except for cowpea and groundnut. Our findings for cowpea and groundnut showed an increase suitable area into the southern Sahel with increasing global warming level. The study holds great value at regional scale where improved preparedness and regional cohesion could make the difference in making decision for a food secure Africa. Further studies to explore associated short and long-term adaptation options to changes in crop-climate relationship are recommended.

Bibliography: leaves 37-41

The total urban area of each study site was calculated for each time slice and the results were represented as maps depicting urban expansion. Graphs were also created depicting the total urban area vs. total population for each time slice (1970s, 1990s and 2000s).

Bibliography: pages 97-102. / The assessment conducted in this dissertation was shaped by the intended formulation of an Integrated Coastal Zone Management Plan (ICZMP), as proposed by the Danish Co-operation for Environment and Development. An ICZMP provides an integrated and holistic approach to planning, in which the various activities and resource demands that occur within the coastal belt and neighbouring regions are appropriately coordinated. The first phase of the formulation of this management plan entailed the compilation of a baseline report summarising the present state of the environment in the study area, with particular emphasis on the major issues which will require attention in an ICZMP. This study was undertaken by Masters students from the Department of Environmental and Geographical Science at the University of Cape Town. The study area is located within the coastal belt of Namibia's Erongo Region, and more specifically within the magisterial districts of Swakopmund and Walvis Bay (Map 3). This includes the National West Coast Tourist Recreation Area and a portion of the Namib Naukluft Park. The southern boundary extends to the Sandwich Harbour, while the northern boundary extends to the southern bank of the Ugab River. The eastern perimeter is that of the Swakopmund magisterial district, and includes the municipal areas of Walvis Bay, Henties Bay and Arandis, together with Rossing Mine and its immediate environment. The seaward boundary is defined by the three nautical mile limit from shore. The Baseline Report: Coastal Zone Management Plan for the Erongo Region, Namibia was submitted to DANCED in March 1996. The findings of the investigation, as recorded in the report, highlight a number of issues which require urgent attention in the ICZMP. One such issue concerns the rapid influx of migrants to the urban centres in the study area. Population is a determining factor which significantly influences the functioning of other key sectors within a given location. As such, an understanding of the ramifications of increased population numbers is imperative to the formulation of an ICZMP. The objective of this dissertation was, therefore, to identify the factors generating rapid migration to the study area, and to facilitate an assessment of the impacts of this phenomenon. Once identified and assessed, these impacts can be better managed within a holistic, integrated framework.

Includes bibliographies. / Urban development and engineering works have resulted in the majority of rivers that drain urban areas being severely degraded, both ecologically and in terms of their potential amenity value. This dissertation explores the reasons for this "spiral of degradation" and it describes the ecological and social impacts on rivers caused by urban development, channelisation and canalisation. It then suggests possible measures to mitigate the impacts at the levels of the catchment, floodplain and river channel. The present cycle of degradation of urban rivers in the Cape Metropolitan Area (and elsewhere) can be halted. In addition, where degradation has already occurred, mitigation and rehabilitation are possible and could restore some of the lost conservation and ecological values, as well as the potential amenity, recreation and education functions. Early colonisation of Cape Town by Europeans inflicted severe impacts on the rivers surrounding and passing through the city. These included: catchment degradation, water abstraction, the disposal of unpurified sewage and industrial effluents, removal of riparian forests, clearing of instream vegetation and the draining of wetlands. During the 20111 century, many urban rivers have been "improved" by straightening or confining within rectangular concrete-lined canals in order to protect urban development in flood-prone areas. The unquestioning faith in technology during this period and the attitude that human ingenuity could "improve nature" are now regarded by the scientific community, together with some local and regional authorities and informed members of the public, as mistakes that resulted in ecological and environmental degradation. These technical solutions merely treated the symptoms of the problem without recognising, let alone attempting to treat, the causes, that is poor catchment and floodplain management. However, there is still a public demand for canalisation of the remaining "natural" rivers in the greater Cape Town area and beyond. At the same time, there has been an increase in environmental awareness, as well as a growing appreciation of the value of holistic and multi-objective planning in the engineering and planning professions. This dissertation aims to assess the impacts of urbanisation, channelisation and canalisation on the aquatic ecosystem and socio-economic environment of urban rivers, and to develop possible measures to mitigate these impacts.

Bibliography: leaves 86-92. / Quarry operations are only a temporary use of the land, while the environmental impacts associated with them are more long term. For this reason, it is unacceptable to merely abandon a quarry once operations have ceased. This study considers the role of rehabilitation in providing solutions for the disturbances caused by quarrying. The value of adopting a pre-planning approach towards rehabilitation is considered, and the components of a rehabilitation programme are identified. Using this information a rehabilitation checklist is drawn up. A survey of thirty rehabilitation reports, submitted to the Cape Town regional offices of the Department of Mineral and Energy Affairs, was undertaken using the checklist. Results of this survey indicate that rehabilitation reports are submitted merely to meet the minimum legal requirements contained in the Minerals Act of 1991 (Act No 50 of 1991). This study recommends that successful rehabilitation will only be achieved when rehabilitation reports function as effective working documents.

The use of genetically modified (GM) crops to resolve food security and poverty issues has been met with controversy and scepticism. The rationale for this research was to highlight the nuanced reasons as to why smallholder farmers are motivated to use agricultural biotechnology. The aim of this study was to explore the uptake of GM maize by South African smallholder farmers in order to contribute towards understanding the implications of agricultural biotechnology in smallholder agriculture. Using the case studies of Hlabisa in KwaZulu-Natal, the objectives were; (i) to investigate the perceived benefits and problems associated with the uptake of GM maize. (ii) to identify which institutional, political, social, and environmental factors influence the choices and decisions made by smallholder farmers to grow GM maize and (iii) to assess how GM maize has affected the well-being of farmers, including social cohesion in the farming communities. The reason Hlabisa was selected for the case study is that it represents one of the few areas in South Africa where GM crops (white GM maize in particular) has been cultivated on a long term basis by smallholder farmers. The necessary information was obtained through the means of a survey in which a number of farmers in the Hlabisa area participated in this regard the participants were; 40 farmers who used white GM maize that possessed the herbicide tolerant and insect resistant traits; seven farmers who used white insect resistant maize and 11 non-GM maize farmers. In addition, five key informant interviews and three focus group discussions were used to collect data. The history of agriculture in the area reveals that modern maize varieties were introduced when agricultural extension officers started operating in the area, beginning with maize seed hybrids in the 1970s. Maize hybrids were framed as better varieties compared to traditional maize in terms of performance. Later, in the 2000s, the seed company Monsanto, and the local department of agriculture introduced various GM maize varieties through farmers' days. This marked the addition of another institution providing so-called expert knowledge about maize farming in Hlabisa. It was argued that relationships between the local department of agriculture, farmers' associations and seed companies were instrumental in encouraging the uptake of GM maize seeds. It is also posited that the GM maize farmers in this study received pseudo-extension and advisory services. These had the agenda of promoting GM maize varieties over traditional varieties, relaying inappropriate agricultural knowledge in the process. There was also a lack of transparency in communicating the potential health and environmental risks associated with GM maize farming. Farmers were unaware that they were legally not allowed to save and exchange the patented GM maize seeds and had to plant refugia to prevent insect resistance. The uptake of GM maize has not significantly affected the seed saving and exchange practices of farmers. Fifty-two percent (24) of the 47 respondents no longer exchanged or saved any of their maize seeds in the study. A chi-squared test for independence indicated that the GM maize farmers were less likely to save and exchange seeds. The non-GM maize farmers were deterred from planting GM crops by the expensive input costs. The issue of affordability of the GM technology also extended to GM farmers, most of whom used social grants to purchase their GM maize seeds. Forty-nine percent of these farmers were in debt due to their uptake of the GM maize. Despite this debt, 74% of respondents claimed that they had perceived an improvement in their quality of life after using white GM maize, as they harvested enough maize to last them to the next planting season and were able to sell surplus maize. However, they only made marginal profits to cover household expenses. There are several conclusions that can be drawn from this study. First, there is a noticeable shift from farmers relying on their own knowledge and experience to using that of seed companies and agricultural extension officers. Second, Seed companies are beginning to fill the gaps left by public extension and advisory institutions and farmers are vulnerable to making uninformed decisions as they are not given relevant information. It is recommended that farmers are given agency through the provision of transparent information. This should be the responsibility of the government and not seed companies with vested interests. The government should try to move away from the idea that farmers need to scale up production through using modern varieties. A better approach would be the strengthening of appropriate support and extension services for South African smallholder farmers who use various maize systems. Lastly there is a need to raise awareness about the social, economic and environmental implications to farmers who elect to use GM seeds.

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