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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Modelling the impacts of increased air temperature on maize yields in selected areas of the South African highveld using the cropsyst model.

Pasi, Jonathan M. 21 July 2014 (has links)
Abstract available in PDF file. / Thesis (M.Sc.Agric.)-University of KwaZulu-Natal, Pietermaritzburg, 2014.
2

Modelling the financial vulnerability of farming systems to climate change in selected case study areas in South Africa

Oosthuizen, Hamman Jacobus 12 1900 (has links)
Thesis (PhD)--Stellenbosch University, 2014. / ENGLISH ABSTRACT: Numerous studies indicate that the agricultural sector is physically and economically vulnerable to climate change. In order to determine possible impacts of projected future climates on the financial vulnerability of selective farming systems in South Africa, a case study methodology was applied. The integrated modelling framework consists of four modules, viz.: climate change impact modelling, dynamic linear programming (DLP) modelling, modelling interphases and financial vulnerability assessment modelling. Empirically downscaled climate data from five global climate models (GCMs) served as base for the integrated modelling. The APSIM crop model was applied to determine the impact of projected climates on crop yield for certain crops in the study. In order to determine the impact of projected climates on crops for which there are no crop models available, a unique modelling technique, Critical Crop Climate Threshold (CCCT) modelling, was developed and applied to model the impact of projected climate change on yield and quality of agricultural produce. Climate change impact modelling also takes into account the projected changes in irrigation water availability (ACRU hydrological model) and crop irrigation requirements (SAPWAT3 model) as a result of projected climate change. The model produces a set of valuable results, viz. projected changes in crop yield and quality, projected changes in availability of irrigation water, projected changes in crop irrigation needs, optimal combination of farming activities to maximize net cash flow, and a set of financial criteria to determine economic viability and financial feasibility of the farming system. A set of financial criteria; i.e. internal rate of return (IRR), net present value (NPV), cash flow ratio, highest debt ratio, and highest debt have been employed to measure the impact of climate change on the financial vulnerability of farming systems. Adaptation strategies to lessen the impact of climate change were identified for each case study through expert group discussions, and included in the integrated modelling as alternative options in the DLP model. This aims at addressing the gap in climate change research, i.e. integrated economic modelling at farm level; thereby making a contribution to integrated climate change modelling. / AFRIKAANSE OPSOMMING: Die fisiese sowel as ekonomiese kwesbaarheid van die landbousektor as gevolg van klimaatverandering word deur verskeie studies beklemtoon. ‘n Gevallestudie-benadering is gebruik ten einde die potensiële impak van klimaatsverandering op die finansiële kwesbaarheid van verskillende boerderystelsels te bepaal. Die geïntegreerde klimaatsveranderingmodel bestaan uit vier modelleringsmodules, naamlik: klimaatsverandering, dinamiese liniêre programmering (DLP), interfases en finansiële-kwesbaarheidsontleding. Empiries afgeskaalde klimatologiese data van vyf verskillende klimaatmodelle dien as basis vir die geïntegreerde klimaatsveranderingmodel. Die APSIM gewas-model word aangewend om die impak van klimaatsverandering op gewasse-opbrengs te bepaal. Vir sekere gewasse is daar egter nie modelle beskikbaaar nie en het gevolglik die ontwikkeling van ‘n nuwe model genoodsaak. Die Kritiese Gewasse Klimaatsdrempelwaarde (KGKD) modelleringstegniek is ontwikkel ten einde die impak van klimaatsverandering op die opbrengs en kwaliteit van gewasse te kwantifiseer. Die geïntegreerde klimaatsveranderingmodel neem ook die verwagte verandering in besproeiingswaterbeskikbaarheid (ACRU-hidrologiemodel) en gewas-besproeiingsbehoeftes (SAPWAT3-model) as gevolg van klimaatsverandering in ag. Die model lewer waardevolle resultate op, naamlik: geprojekteerde veranderinge in gewasse-opbrengs en -kwaliteit, geprojekteerde verandering in beskikbaarheid van besproeiingswater en gewasse-besproeiingsbehoeftes, die optimale kombinering van boerdery-aktiwiteite om netto kontantvloei te maksimeer, asook ‘n stel finansiële resultate wat die impak van klimaatsverandering kwantifiseer. Die finansiële kriteria sluit in: interne opbrengskoers, netto huidige waarde, kontanvloeiverhouding, hoogste skuldverhouding en hoogste skuldvlak. Deur middel van deskundige-groepbesprekings is aanpassingstrategieë vir elk van die gevallestudies geïdentifiseer en by die geïntegreerde model ingesluit as alternatiewe opsies in die DLP-model. Die studie poog om die gaping in die huidige klimaatsveranderingnavorsing met betekking tot ‘n geïntegreerde ekonomiese model op plaasvlak aan te spreek en sodoende ‘n bydrae tot geïntegreerde klimaatveranderingmodellering te maak.
3

The impact climate change on rural households in Binfield village

Tabalaza, Nomthetho January 2017 (has links)
Climate change poses a major environmental challenge, due to its adverse effects on human settlement patterns and food security. The global phenomenon upsets seasonal shifts, leading to changes in planting dates and weather patterns. This unpredictability has severe and adverse effects on farmers and rural communities, as variable environmental factors govern activities related to daily sustenance and food availability. The kind of rapid and intense climate change that South African rural spaces are experiencing now, increase the likelihood of extreme weather events such as droughts, heat waves and floods. There are growing concerns that the rural poor will be unable to adapt. Rural livelihoods are therefore facing overwhelming and extensive environmental threats, while rural dwellers are finding it difficult to adapt and cope. As a result, climate change can thus be described as one of the most complex and dangerous environmental problems challenging rural livelihoods today. The aim of this study was to explore the impact of climate change on rural poverty at Binfield village in the Eastern Cape and to identify the livelihood activities practiced. Furthermore, the research was conducted to ascertain how rural livelihood activities are affected by climate change and identify and assess the effectiveness of adaption strategies employed by the households. The research also aimed to explore and establish further adaptation strategies. This study made use of a qualitative research method. Babooa (2008) argues that qualitative research is concerned with stories and accounts including subjective understandings, feelings, opinions and beliefs. The study used both primary and secondary data for data. The researcher adopted interviews and field observation for primary data whilst secondary data was sourced from journals, articles and internet sources. O‘ Leary (2004) describes the interview as a method of collecting data where the interviewer asks the Interviewee open-ended questions. The questions were based on the key areas of interest. Qualitative research methods are aimed at understanding the rich, complex characteristic nature of human phenomena. Qualitative methods are concerned with understanding human behaviour from the participant‘s own frame of reference.
4

Evaluating summer cover crop species and management strategies for rainfed maize based cropping systems in the central region of the Eastern Cape Province of South Africa

Ganyani, Lloyd Munashe January 2011 (has links)
The overall objective of the whole study was to assess whether conservation agriculture (CA) systems can work in the Eastern Cape Province (EC). The CA systems were engaged through cover cropping to address land degradation problems by emphasizing high biomass production in order to realize short term benefits such as moisture conservation, weed suppression and soil fertility benefits under rainfed conditions in the central region of the Eastern Cape province. Since rainfall is the most limiting factor to crop production in the EC, a within season rainfall distribution analysis was conducted to expose the quality of the season (onset, end and duration) and hence the feasibility of CA systems to guide agronomic decisions by farmers in EC. To assess season parameters, thirty four years of daily rainfall was collected from the University of Fort Hare Research station and used to conduct the rainy pentad (5 day rainfall totals) analysis and the daily rainfall analysis using INSTAT software programme. Based on the pentad analysis, results showed that Alice does not have a rainy season in 1 out of 2 years (50% probability) but has one in 1 out of 4 years (25% probability level). This criterion proved to be harsher and conservative when compared to the daily rainfall approach which is more precise in measuring trends on season parameters. The daily rainfall analysis indicated a 65% feasibility for the dry land cropping systems in the EC. The pentad analysis however was effective in illustrating seasonality and it showed that the wet season begins on the 1st of November, ending on the 22nd of March lasting for 140 days. Though the season duration appeared too long, the existence of dry spells during critical growth stages adversely affects the quality of the season. The daily rainfall analysis also managed to derive a signal which can guide planting decisions. For planting to be successful, this analysis determined that 20 mm of rain should be received in two consecutive days after the 1st of November. A screening trial for cover crop biomass production and weed suppression was conducted on-station Fort Hare Research Farm (32°46' S and 26° 50' E), and Msobombvu village (MSBV) (32°44' S, and 26° 55' E) over two seasons (2007/08 and 2008/09). Six summer cover crops i.e. cowpea (Vigna unguiculata), dolichos lablab (Dolichos argenteus), sunnhemp (Crotalaria juncea), buckwheat (Fagopyrum sagittatum), forage sorghum (Sorghum bicolor) and sunflower (Helianthus annus) were evaluated for biomass yield, and weed suppression. Decomposition rates, moisture conservation and residual effects of these cover crops on the succeeding main crop were also evaluated under dryland conditions. The screening trial was laid in randomized complete block design replicated three times. Forage sorghum (Sorghum bicolor) and sunflower (Helianthus annus) were identified as high biomass producers and their dry matter yields ranged from 8 -12 t ha-1. These cover crops can be useful in generating high biomass in rainfed cropping systems in the EC. Other cover crops produced 3 - 4 t ha-1 of biomass which fell short of the 6 t ha-1 expected benchmark. However, these biomass yields were important in weed management since all cover crop species showed a similar degree of weed suppression which surpassed the weed fallow treatment. As dead mulches, the cover crops failed to show residual moisture conservation and weed control benefits for the succeeding maize crop mainly because of poor residue persistence, and low harvestable fallow rainfall. Buckwheat (Fagopyrum esculentum), was selected for further investigations in a follow up trial on station in 2008/09 season because of its weed smothering qualities, suitability to short cycle rotations, and possible allelopathic properties. The trial aimed at finding weed and cost effective management options of buckwheat that are none detrimental to the succeeding maize crop. Results showed that cropping systems where buckwheat is followed by a main crop may not work as they are unprofitable with respect to R100 rand invested. Though perceived to have allelopathic properties, buckwheat failed to demonstrate the possibilities of allelopathic action against weeds. Intercropping trial was conducted on-station in 2007/8-2008/09 seasons to try and find better ways of fitting legume cover crops into maize based cropping systems without compromising production of staple cereals on limited landholdings. The trials evaluated three factors in factorial combination, cover crop planting date, intercropping strategy, and cover crop species. The trial was laid as 2 x 2 x 3 factorial arranged in a split-split plot design. The main plot factor was cover crop planting date, cover crops simultaneously planted with maize and cover crop planted two weeks after planting maize (DKC 61-25). The sub-plot factor was intercropping strategy, strip intercropping and betweenrow intercropping. The sub-sub-plot factor was cover crop species, Dolichos lablab (Dolichos argenteus (Highworth), and Cowpea Vigna ungiculata (Agrinawa) plus control plots of sole maize. Results showed that same time planting of leguminous cover crops with maize using the in-between row intercropping patterns can derive appreciable system biomass (maize/cover crop) yields, utilize land efficiently whilst getting favourable maize grain yield. Based on the rainfall analysis, results showed that the probability of success when relay seeding cover crops after two weeks into standing maize is low (15% chances of success). This suggests that relay intercropping strategies would not work due to the unavailability of a good quality season.
5

Farmers’ awareness of climate change and variability and it’s effects on agricultural productivity: (the case of King Sabata Dalindyebo Municipalty in Eastern Cape)

Mdoda, Lelethu January 2014 (has links)
Climate is an important factor of agricultural productivity and many rural dwellers in developing countries depend on agriculture and are highly affected by climate change and variability. The world is currently experiencing climatic changes and variability conditions which results in high temperatures, low rainfall patterns, shortage of water and drought persistence. Climate change and variability is affecting weather patterns and shifting seasons which results in serious repercussions on smallholder farmers. Smallholder farmers are extremely vulnerable to climate change and variability because their farming and production systems are climate sensitive and are not rebound to climate stresses. These adverse effects in developing countries arise from different climate change and variability-related causes, notable extreme weather events, food security, increased health risks in agriculture from vector home diseases, and temperature-related morbidity in environments. The study was carried in King Sabata Dalindyebo Municipality in the Eastern Cape Province in South Africa. This study examines farmers’ awareness of climate change and variability and its effects on agricultural productivity in King Sabata Dalindyebo municipality using a Descriptive Statistics, Binary and Ricardian Model fitted to data from a cross-sectional survey of 200 farmers in King Sabata Dalindyebo Municipality. Both primary and secondary data was used. This research study estimates the effects of climate change and variability on King Sabata Dalindyebo agricultural productivity using a continental dimension of Ricardian analysis. Results revealed that local farmers were aware of climate change and variability and perceived changes in average temperatures and rainfall. The changes in average temperatures and rainfall had adverse effects on crop and livestock production. However, farmers’ awareness of climate change is not to an extent that they presume adaptation to climate change as a necessity and crucial. The results show that climate change and variability affects farm income and there is a non-linear relationship existing between climatic variables (temperature and precipitation) and farm income which depicts U-shaped. The study results indicated that climate change and variability affect agricultural productivity and have an effect on agricultural productivity in King Sabata Dalindyebo Municipality. In view of the research findings, several policy proposals are suggested. The study findings suggest that climate change and variability must be taken seriously and monitored. Policy makers and government officials must support farmers with information distribution,education, market access, well trained extension agents, credit and information about mitigation strategies to climate change and variability which includes institutional and technological methods, particularly smallholder farmers.
6

Climate change and agricultural production in Limpopo Province : impacts and adaptation options

Maponya, Phokele Isaac 12 1900 (has links)
The primary aim of my research was to identify the impacts and adaptation options of climate variability and change on agricultural production in Limpopo province. The following objectives were identified: To understand the impacts of climate variability and change on agricultural production in Limpopo province , To assess the impacts of climate variability and change on agricultural production in Limpopo province and To identify adaptation measures that reduces the impacts of climate variability and change on agricultural production in Limpopo province. A representative sample of 300 farmers aged 16- 65+ years (46 percent males and 54 percent females) participated in the study. The study involved Sekhukhune and Capricorn districts, with 56 percent farmers in Capricorn and 44 percent in Sekhukhune district. The following 11 local municipalities were visited: Elias Motsoaledi, Makhuduthamaga, Fetakgomo, Ephraim Mogale, Tubatse, Lepelle Nkumpi, Blouberg, Aganang, Polokwane, and Molemole. The Limpopo province is one of the poorest provinces in the country, characterized by high unemployment rate, poverty and lack of access to a range of resources that frustrate majority of people ability to secure their livelihoods. In this study the province's economic, biological and physical environment were highlighted. The study further covers the province, s farming enterprises, systems, categories, infrastructure as well as other constraints that maybe facing the emerging farmer in the province. It is assumed that the majority of farmers in both the Capricorn and Sekhukhune districts are using different coping and adaptation strategies in order to increase their crop yields. Literature studies show that climate variability and change adaptation strategies vary from area to area due to agro ecological zones and the harshness of the effects of climate variability and change. It has also been noted that climate change is fast pushing the poorest and most marginalized communities beyond their capacity to respond. This study draws on lessons learned, experiences, and other existing research on climate change impacts and adaptation across the globe. It sets out what is needed to enable people living in poverty to adapt to climate change, and a range of interventions that are available across climate - sensitive sectors. The study has provided a literature review of the impact of climate change on the agricultural sector. In fact, it has documented some of the likely impacts of climate change based on International, continental, regional, national and provincial agricultural sector. The study highlighted the impact of climate change also on various climate - sensitive sectors including understanding water resources, forestry, natural ecosystem human health, infrastructure and coastal zones. This research also confirmed that being a full time farmer, gender, information on climate change, information received through extension services and adaptation to climate change are some of the important determinants of agricultural production, food scarcity and unemployment. A worrying situation is reviewed globally in this study and it can be concluded that climate variability and change is affecting every sector in society and it needs urgent attention. Statistics was used to determine climate variability and change impact on agricultural production. Results indicate that farmers are aware that Limpopo province is getting warmer and drier with increased frequency of droughts, changes in the timing of rains, observed trends oftemperature and precipitation. The study also presented perceived adaptation strategies used by farmers in Limpopo province. Some of their perceived adaptation strategies included: (a) Soil management strategies, (b) Water management strategies and (c) Others like use of subsidies and use of insurance. Other important adaptation options being used by farmers were also discussed in this study including different adaptation measures against colds, heat, frost, abnormal wind, hail, lack of extension support, nematodes, insecticides, worms, temperature and rainfall. The results of this study are potentially valuable to the agricultural sector considering the threats that climate change poses across climate sensitive sectors. / Environmental Sciences / D. Phil. (Environmental Management)
7

The impact of climate change on agricultural crop production in the Vhembe District Municipality, Limpopo Province South Africa

Musetha, Mboniseni Aubrey 09 1900 (has links)
The aim of this research was to identify the impacts and adaptation options of climate variability and change on agricultural crop production in Vhembe District Municipality. The study will contribute to the expansion of existing literature on climate change impacts on agricultural sector. The following two main objectives were formulated for the purpose of this study:  To determine the level of awareness of small-scale maize farmers about climate change impacts and threats in Vhembe District Municipality (VDM),  To compare the level of production scales between the farmers who are aware and the farmers who are not aware of climate change impacts and its threats. The study area was the Vhembe District Municipality; a representative sample of 150 farmers (aged 18 – 65+ years, 46 percent males and 54 percent females) participated in the study. Vhembe District Municipality is one of poorest municipalities in Limpopo due to lack of infrastructure development, and as a result of that, there is an increase of socio-economic problems such as food prices increase, unemployment, scarcity of food, and lack of local markets. The study further covers the municipality’s farming enterprises, systems, categories, infrastructure as well as other constraints that may be facing the emerging farmer in the District. The study highlighted the lack of climate change information, reduction of livestock production and crop yields of the farmers in the Vhembe District. The literature studies show climate variability and change adaptation strategies such as planting different varieties, crop diversification, different planting dates and shortening of growing periods. This study draws on lessons learned, experiences, and other existing research on climate change impact and adaptation across the globe. It was concluded during the research that change in climate was already perceived by farmers in the Vhembe District and the study also presented perceived adaptation strategies used by farmers in the Vhembe District. The study concludes that there is lack of local market, and low level of farmers’ awareness about the impact of climate change on the crop production in the Vhembe district. This low level of awareness translates into a low level of crop production which results in increased socio-economic problems, low income, increased unemployment, increased crops diseases and reduced crop yields. / Environmental Sciences / M. Sc. (Environmental Management)
8

Climate change and agricultural production in Limpopo Province : impacts and adaptation options

Maponya, Phokele Isaac 12 1900 (has links)
The primary aim of my research was to identify the impacts and adaptation options of climate variability and change on agricultural production in Limpopo province. The following objectives were identified: To understand the impacts of climate variability and change on agricultural production in Limpopo province , To assess the impacts of climate variability and change on agricultural production in Limpopo province and To identify adaptation measures that reduces the impacts of climate variability and change on agricultural production in Limpopo province. A representative sample of 300 farmers aged 16- 65+ years (46 percent males and 54 percent females) participated in the study. The study involved Sekhukhune and Capricorn districts, with 56 percent farmers in Capricorn and 44 percent in Sekhukhune district. The following 11 local municipalities were visited: Elias Motsoaledi, Makhuduthamaga, Fetakgomo, Ephraim Mogale, Tubatse, Lepelle Nkumpi, Blouberg, Aganang, Polokwane, and Molemole. The Limpopo province is one of the poorest provinces in the country, characterized by high unemployment rate, poverty and lack of access to a range of resources that frustrate majority of people ability to secure their livelihoods. In this study the province's economic, biological and physical environment were highlighted. The study further covers the province, s farming enterprises, systems, categories, infrastructure as well as other constraints that maybe facing the emerging farmer in the province. It is assumed that the majority of farmers in both the Capricorn and Sekhukhune districts are using different coping and adaptation strategies in order to increase their crop yields. Literature studies show that climate variability and change adaptation strategies vary from area to area due to agro ecological zones and the harshness of the effects of climate variability and change. It has also been noted that climate change is fast pushing the poorest and most marginalized communities beyond their capacity to respond. This study draws on lessons learned, experiences, and other existing research on climate change impacts and adaptation across the globe. It sets out what is needed to enable people living in poverty to adapt to climate change, and a range of interventions that are available across climate - sensitive sectors. The study has provided a literature review of the impact of climate change on the agricultural sector. In fact, it has documented some of the likely impacts of climate change based on International, continental, regional, national and provincial agricultural sector. The study highlighted the impact of climate change also on various climate - sensitive sectors including understanding water resources, forestry, natural ecosystem human health, infrastructure and coastal zones. This research also confirmed that being a full time farmer, gender, information on climate change, information received through extension services and adaptation to climate change are some of the important determinants of agricultural production, food scarcity and unemployment. A worrying situation is reviewed globally in this study and it can be concluded that climate variability and change is affecting every sector in society and it needs urgent attention. Statistics was used to determine climate variability and change impact on agricultural production. Results indicate that farmers are aware that Limpopo province is getting warmer and drier with increased frequency of droughts, changes in the timing of rains, observed trends oftemperature and precipitation. The study also presented perceived adaptation strategies used by farmers in Limpopo province. Some of their perceived adaptation strategies included: (a) Soil management strategies, (b) Water management strategies and (c) Others like use of subsidies and use of insurance. Other important adaptation options being used by farmers were also discussed in this study including different adaptation measures against colds, heat, frost, abnormal wind, hail, lack of extension support, nematodes, insecticides, worms, temperature and rainfall. The results of this study are potentially valuable to the agricultural sector considering the threats that climate change poses across climate sensitive sectors. / Environmental Sciences / D. Phil. (Environmental Management)
9

Adaptation strategies for climate change-induced household food and nutrition insecurity in smallholder maize farming within Thulamela Local Municipality, South Africa

Mahlawule, Khanyisa Dorris 18 September 2017 (has links)
MRDV / Institute for Rural Development / See the attached abstract below
10

An analysis of perceptions amongst farmers on the adoption of GM technology in Paarl, Western Cape - South Africa

Owusu, Festus 08 1900 (has links)
In early 2003, a persistent drought threatened about 15 million people in the Southern African region (SADC) with starvation as farmers in this region were not able to produce enough food. A similar threat was experienced in the United States of America (USA). The Americans responded by introducing GM technology, which thankfully stabilised corn production and food security. It was against this backdrop that the South African government legalised and supported GM technology in the farming industry. However, the technology became a contentious issue amongst scholars, politicians and policy makers as well as farmers. Therefore, this study analysed the perceptions of small-scale and large-scale farmers, located in Paarl, Western Cape, South Africa, on the adoption of GM technology. This qualitative study, using a case study design, collected primary data from thirty (30) farmers: fifteen (15) small-scale and fifteen (15) large-scale farmers. The findings revealed complex factors influencing farmers’ adoption decisions and that Adopter perception (AP) and Consumer perception (CP) play a key role in their adoption of GM technology. These commercially and profit-driven farmers avoid using GM technology because public opinion and the markets weigh heavily against it. It was concluded that the farmers regarded GM technology as just one of many agricultural technologies and not as an exception. It was also considered unaffordable and detrimental to the environment, the economy and their livelihoods.The study recommends that the government should fully investigate public perceptions with regard to the adoption of any new agricultural innovation prior to making policy decisions. / Development Studies / M.A. (Development Studies)

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