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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.
111

The role of irrigation policies in expanding irrigated food production in Mozambique.

Gêmo, Hélder R. January 2012 (has links)
In recognition of the crucial role irrigation plays in stabilizing agriculture production in the face of erratic rainfall that often affects Mozambique, the Government has, since national independence in 1975, implemented several policies regarding irrigation development. Yet, the country is still struggling to expand the area equipped for food crop irrigation. In particular, the formulation and implementation of irrigation policies has faced constraints in the expansion and effective use of irrigated land to ensure increased food production. Despite this, there has not been a systematic effort to consistently document and identify constraints and enablers of irrigation policies and development in to support evidence-based policy dialogue and interventions. This study intends to fill this gap. It does this through an analytical historical trajectory of the irrigation subsector, paying particular attention to critical factors affecting the effectiveness of irrigation policies in contributing to the expansion and effective use of irrigated land to enhance agriculture’s contribution to food production and food security in Mozambique. A qualitative approach is employed in which a review of the existing literature and official documents, along with secondary data collection, is augmented with interviews of key informants and expert opinions. The analysis posits that the ability of irrigation policies to effectively contribute to an expansion and improvement of irrigated production can be enhanced through addressing issues of policy weaknesses, limited investment resources to expand irrigated land, inadequate public institutional support to the irrigation subsector, especially at field level, limited involvement of the private sector in irrigation, weak farmers’ organizations (FOs) and water users associations (WUAs) on irrigated land as well as weak information and knowledge generation and sharing among relevant stakeholders. These issues are particularly pertinent in light of the anticipated implementation of the 2010 Irrigation Strategy. The role, cooperation and partnerships among Government, private sector, FOs/WUAs and development partners need to be taken into account in the formulation and implementation of public irrigation policies. Overall, it is important to note that the success of irrigation depends critically on other agriculture sector-wide policies, suggesting that it is important to have a comprehensive agricultural development policy in place. / Thesis (M.Sc.Agric.)-University of KwaZulu-Natal, Pietermaritzburg, 2012.
112

Impact of smallholder irrigation schemes on rural livelihoods of farmers in the Eastern Cape Province of South Africa: the case of Melani Irrigation Scheme

Magqibelo, Sinovuyo January 2016 (has links)
Irrigation farming is one of the most important rural development investments that can have both direct and indirect impacts on poverty and food security. The irregular and unreliable rainfall in the Eastern Cape Province has caused the smallholder farmers to deepen the irrigation farming systems as a strategy to cope with food shortage, income and poverty. South Africa has invested substantially in smallholder irrigation to benefit smallholder farmers in the less developed areas. Although the investment on small scale irrigation was to improve the welfare of the people, the performance and welfare impact of smallholder irrigation schemes has been poor and fall far short of the expectations of many stakeholders. The broad objective of the study was to examine the contribution of smallholder irrigation scheme on rural livelihoods of smallholder farmers at the project area. The null hypothesis was that smallholder irrigation schemes have no impact on farmer’s livelihoods. The alternative hypothesis for this study was that Melani irrigation scheme is contributing in improving rural livelihoods of smallholder farmers in the area. Cross study research design was used in the methodology. The purposive sampling was applied in order to choose a sample of 107 respondents that were interviewed using questionnaires, including both irrigating and non-irrigating farmers. A multiple linear regression analysis was used to find out whether the performance of the two groups of farmers is different and to what extent. To determine the specific role of irrigation an Independent T-Test was ran. Out of the selected sample 68 percent of households were farmers, 7.5 percent informal employed and 27 percent unemployed. It was found that the majority of participants were males and were uneducated. They depended on social grants for a living. The findings from the study showed that 84 percent of the respondents agreed that there is no market available in the village and farmers had limited access to credits. The crop income was the most contributing factor to household income. The results showed that whether the farmer is a non-irrigator or an irrigator the performance is not significant. Irrigation scheme improvement attained by smallholder farmers need to be maintained.
113

Projeto de uma mesa de subirrigação para ambientes protegidos / Design of greenhouse subirrigation bench

Ribeiro, Maycon Diego, 1988- 22 August 2018 (has links)
Orientador: Roberto Testezlaf / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Agrícola / Made available in DSpace on 2018-08-22T21:34:01Z (GMT). No. of bitstreams: 1 Ribeiro_MayconDiego_M.pdf: 3280137 bytes, checksum: 9c253671fd642a329f3232738ee0af37 (MD5) Previous issue date: 2013 / Resumo: No cultivo em ambientes protegidos, o uso da irrigação é necessário, requerendo alta frequência e gerando dependência tecnológica do produtor na aplicação de água e fertilizantes. Irrigações inadequadas potencializam problemas, trazendo prejuízos financeiros pela baixa produtividade e desperdício de solução nutritiva (SN) e energia. Adicionalmente, o descarte inadequado desses insumos pode contaminar o solo e, consequentemente, o lençol freático. Estudos mostram que os sistemas de subirrigação têm potencial para obter altas eficiências na irrigação nesses ambientes, principalmente, quando há a recirculação da solução nutritiva. Porém, os equipamentos existentes atualmente no mercado foram desenvolvidos sem critérios de engenharia e produzidos em pequena escala para atender condições específicas de produção resultando em elevado custo inicial. Adicionalmente, a falta de conhecimentos sobre a sua aplicabilidade para diferentes sistemas de produção e sobre recomendações do manejo hídrico e nutricional para culturas distintas, proporciona outra limitação na sua aplicação, desencoraja sua adoção pelos produtores. O projeto e construção de uma mesa de subirrigação utilizando critérios de engenharia, que permitam o reuso da SN e o controle automático do manejo hídrico nutricional para diferentes culturas, disponibilizará um equipamento com potencial para ser inserido no mercado nacional de produção em ambientes protegidos. O objetivo desse trabalho foi projetar uma mesa de subirrigação automatizada com reuso da SN, a partir da aplicação de critérios de projeto de engenharia. Essa pesquisa foi dividida nas seguintes etapas: levantamento de informações sobre sistemas de subirrigação existentes no mercado, avaliação de campo de um sistema em operação, estabelecimento de parâmetros de dimensionamento por simulação, e a construção e avaliação de protótipo de equipamento. Os levantamentos realizados não localizaram fabricantes nacionais de equipamentos de subirrigação, e mostraram que os equipamentos em operação apresentavam projetos desenvolvidos empiricamente e construídos a partir de demanda específica do produtor. O sistema de subirrigação em operação avaliado apresentou baixa eficiência de irrigação e aplicação de água devido a perdas e ao descarte de SN. Os critérios adotados para o projeto da mesa de subirrigação foram ergonômicos e de segurança, funcionalidade e aplicabilidade, a escolha do material construtivo. A aplicação dos critérios adotados possibilitou o estabelecimento das seguintes características da mesa de subirrigação: largura de 1,58 m, comprimento variável, altura da borda de 0,06 m, chapa de poliestireno de alto impacto para a mesa e perfis de alumínio para a estrutura. A variação da combinação da vazão e do diâmetro do orifício de dreno associado ao controle automático do nível da lâmina na mesa de subirrigação atendem as exigências de manejo hídrico de diferentes culturas possibilitam a redução do uso de mão de obra e evita descartes com a recirculação da SN. Os resultados de avaliação da mesa de subirrigação construída permitiram identificar diferentes combinações de manejo associada à variação da altura e tempo de permanência da SN no interior da mesa. Concluiu-se que a mesa de subirrigação construída a partir de critérios de projeto de engenharia, com controle automático da reutilização da SN, tem potencial para ser inserido no mercado de ambiente protegido, tendo a opção de ser empregada em diferentes recipientes de produção, cultura e manejo / Abstract: Irrigation is a mandatory practice in greenhouse production, requiring high frequency and generating farmer technological dependency in water and fertilizers application. Low irrigation efficiencies increase production problems, bringing financial losses due to low yield and nutrient solution (NS) waste and energy cost. Additionally, the unsuitable disposal of these inputs can contaminate the soil and hence, the water resources. Studies showed that subirrigation systems have the potential for high efficiencies in greenhouse irrigation, especially when the recirculation of the nutrient solution is employed. However, subirrigation equipments currently available on the Brazilian market were designed without engineering criteria and produced on a small scale to meet specific production conditions, determining high initial investment cost. Furthermore, the lack of knowledge about its applicability to different production systems and water and nutritional management for distinct crops, provides another restriction in its application, and discourages producers in adopting this system. The design and construction of a subirrigation bench based on engineering criteria, enabling the NS reuse and the automatic control of water and nutrient management for different crops will provide a device with the potential to be introduced in the domestic market of greenhouse production. The objective of this work was to design an automated subirrigation bench with NS reuse, applying the fundamentals of engineering design criteria. This research was divided into the following steps: an information survey on commercial subirrigation systems, a subirrigation system field evaluation, and establishment of parameters for sizing simulation and the construction and evaluation of prototype equipment. The survey results do not tracked national companies that manufacture detailed subirrigation equipment, and shown that equipment found in farm operations was designed and developed empirically and constructed from specific producer demands. The evaluated subirrigation system revealed low values of irrigation and water application efficiencies due to NS losses and frequent disposal. The criteria adopted for the subirrigation bench design were based on ergonomic and safety, functionality and applicability issues, and the manufacture material selection. The implemented design criteria enabled the establishment of the following subirrigation bench features: width 1.58 m, length adjustable, edge height of 0.06 m, high impact polystyrene sheets for the bench frame and aluminum sheets for the supporting structure. The combinations of operation flow rate and drain orifice diameters, associated to the automated level control, allowed to establish water and nutrient management for different crops, reducing manpower needs and avoiding NS disposal due to the recirculated practice. The evaluation results of the assembled subirrigation bench showed that different management combinations can be performed by varying the NS depth and its residence time inside the equipment. It was concluded that the subirrigation bench constructed based on engineering design criteria, with automated management system and NS reuse, has the potential to be introduced in the greenhouse production market, with the option to be implemented to various crops and containers / Mestrado / Agua e Solo / Mestre em Engenharia Agrícola
114

Evaluation and mapping of the spatial variability of soil fertility at Zanyokwe Irrigation Scheme in the Eastern Cape, South Africa

Manyevere, Alen January 2010 (has links)
No description available.
115

Analysis of decision making in smallholder irrigation practice: a case study of Shiloh and Zanyokwe irrigation schemes in Central Eastern Cape, South Africa

Isaac, Agholor Azikiwe Unknown Date (has links)
The study was conducted in Zanyokwe and Shiloh smallholder irrigation schemes located in Eastern Cape Province at Amathole and Chris Hani districts respectively. The choice of Zanyokwe and Shiloh smallholder irrigation scheme for this study is mainly supported by the fact that it had a substantial level of crop farming activity taking place especially at Zanyokwe while the Shiloh smallholder irrigation specialises dairy farming. The study examined decision making in smallholder irrigation practice with particular reference to Shiloh and Zanyokwe irrigation schemes. The general objective of the thesis was to analyse and model the determinants of SIS farmer‟s decision making. The specific objectives of the study are as follows: to investigate the determinants of decision making among smallholder irrigation farmers; to examine the relationship between household and farm characteristics and institutional factors that explain decision making in smallholder irrigation scheme; assess the contribution of smallholder irrigation farming to household food security; and determine the production and marketing constraints of smallholder farmers‟ in both schemes. The theoretical and conceptual framework of the study gave a detailed discussion on the determinants of decision making of households. The theories used to understand household behaviour under different assumptions were variously discussed. Comprehensive illustrations of analytical framework of the study were also conceptualised. This study used a survey design, quantitative and qualitative research methodologies involving the use of questionnaires and focus group discussions. The data was coded and analysed using the Statistical Package for Social Science (SPSS). However, frequencies, percentages, bar and pie chart was also computed to describe the data. In consideration of the conceptual framework of the study, the agricultural household model was adopted to analyse smallholder farmer‟s household decision making. Twenty one explanatory variables identified in the conceptual framework of the study were discussed and some of these identified variables were incorporated into the model. The logistic regression model was used as a method of analysis because it can estimate the probability of a certain event occurring and it accommodates a lot of variables which can be ranked in order to illustrate which variables are significant. In the binary logistic model used, seven variables (farm experience, size of farmland, land rights/PTO, water sufficiency, farm asset, market information and production variation) out of the twelve predictor variables were found to have significant effect on influencing household decision making in Shiloh smallholder irrigation scheme, while five variables (gender, age, education, road distance and extension access) were not significant. Of the seven significant variables, four had positive signs (land rights/PTO, water sufficiency and market information); which means that an increase in either of these variables may be associated with an increase in household decision making in Shiloh. The other three predictor variables (farm experience, farm asset and product variation) had negative signs; this means an increase in either of these variables may be associated with a decrease in decision making. In Zanyokwe, six variables (farm experience, land rights/PTO, water sufficiency, farm asset, market information and production variation) out of the twelve predictor variables were found to have significant impact on influencing household decision making, while six variables (gender, age, education, size of farm land, road distance and extension access) were not significant. Of the six significant variables, two had positive signs (water sufficiency and farm asset); which means that an increase in either of these variables may be associated with an increase in household decision making in Zanyokwe. The other four predictor variables (farm experience, land rights/PTO, market information and product variation) had negative signs; this means an increase in either of these variables may be associated with a decrease in decision making. The study concludes that smallholder agriculture is essential for employment generation and food security of households. It is apparent that household food security will not be achieved without giving attention to the role played by smallholders‟ farmers in South Africa. It is pertinent to promulgate an efficient policy programme to address the diversity of smallholders‟ situations and identify the main constraints on investment. Therefore, all spheres of government, the private sector and NGOs should consider investment in smallholder agriculture through coordinated strategies and political support. This study also recommends that government should develop a strategic Smallholder Investment Plan which would improve investments in smallholder agriculture.
116

Analysis of entrepreneurial behaviour of smallholder irrigation farmers: empirical evidence from Qamata Irrigation scheme

Chitsa, Gilbert January 2014 (has links)
Albeit much effort having been put to review the performance trend of smallholder irrigation farmers in South Africa. However, there seems to be a paucity of information regarding the level of entrepreneurship on these farmers. Most research works on smallholder irrigation farmers have mainly focused on livelihoods trajectory providing a review on how the welfare of the rural poor has been transformed after the introduction of irrigation schemes. With most research evidence indicating a high degree of underperformance on most smallholder irrigation schemes, this research attempted to investigate the level of entrepreneurship among the small holder irrigation farmers. In order to achieve the main research objective, a sample of 110 farmers drawn from Qamata irrigation scheme was interviewed and each farmer’s performance on the nine components of entrepreneurship was assessed. The aspects assessed to determine the farmer’s entrepreneurial behaviour were: planning ability, risk taking, achievement motivation, leadership ability, Cosmo politeness, decision making, and innovativeness and farming knowledge. Basing on previous studies which indicated entrepreneurial behaviour to be influenced by several factors the study also analysed the determinants of entrepreneurship among the irrigation farmers and a binary logistic regression model was used to establish the connection between various independent variables and the farmers’ entrepreneurial performance given as a total score of the nine components. Though the findings of the study revealed a prevalently low level of entrepreneurship among the smallholder irrigation farmers on Qamata irrigation scheme, a high proportion of the respondent farmers (65.5% and 60.5%) showed to have a high degree of achievement motivation and decision making ability, respectively. The observed trend thus reflected that smallholder farmers have a potential to become entrepreneurs and are willing to succeed. The binary model results revealed that the prevailing land tenure system will be a strong determinant of the farmer’s level of entrepreneurship. Equally, levels of training in farming, motive for farming and information seeking tendency also proved to have a significant influence on the degree of farmer entrepreneurship. Based on the results of this study recommendations have thus been drawn on the need for policies and practices aimed at promoting entrepreneurship and not dependency among farmers. Key focus areas identified include: the need to revise the current land ii tenure system on irrigation schemes, intensify on entrepreneurship training for both farmers and extension officers and regular on-farm training on new technologies.
117

A systems approach to marketing in less developed agriculture with reference to Bululwane Irrigation Scheme

Zenda, Sipho Macriba January 2002 (has links)
No description available.
118

Interactive effects of Bacillus subtilis and elevated temperature on germination, growth and grain quality of cowpea irrigated with acid mine drainage

Nevhulaudzi, Thalukanyo 02 1900 (has links)
This study’s main goal was to evaluate Bacillus subtilis inoculation and mine water irrigation effect on germination, growth, nodulation, physiology and shoot/grain quality of cowpea genotypes exposed to extreme climatic conditions (elevated temperatures). The first experiment evaluated the interactive effect of Bacillus subtilis (BD233) inoculation and elevated temperature on germination indices and plumule lengths of three genotypes (Asetanapa, Soronko and Nyira) of cowpea. The results showed that interaction between B. subtilis (BD233) and temperature significantly (p<0.05) influenced the germination indices (germination percentage (G%), germination index (GI) and germination rate index (GRI)) and plumule length of cowpea seedlings and genotype responses were significantly different. At elevated temperature (35oC), inoculation with B. subtilis (BD233) enhanced seed germination and growth of cowpea. The second experiment evaluated the effect of temperature on growth and nutritional content of cowpea incubated for seven days in a growth chamber. The results showed that when cowpea genotype, Soronko, was incubated at different temperature regimes, the whole plant biomass, shoot carbon and crude protein contents were significantly affected with temperature increases at all three stages of the plants’ life cycle. The results suggest that the pre-flowering (40 DAP) and flowering (90 DAP) stages of cowpea compared to post-flowering (123 DAP) are more susceptible to elevated temperatures (30-35oC). The third experiment evaluated Bacillus subtilis inoculation and mine water irrigation effect on growth, nodulation, physiology and nutritional content of cowpea under glasshouse conditions. The results revealed that the interaction of B. subtilis (BD233) inoculation and mine water (75% AMD) irrigation was significant for the growth, nodulation, stomatal conductance, chlorophyll contents and shoot/grain nutritional quality of cowpea genotypes. In comparison with control, generally, B. subtilis inoculation enhanced the growth, nodulation and yield of all tested cowpea genotypes and irrigation with mine water significantly influenced the mineral contents in both shoot and grain of cowpea. Taken together, findings in this study have implications for cultivation of cowpea, an important candidate for food/nutrition security in Africa, under future climate change scenarios. / Environmental Sciences / M. Sc. (Environmental Sciences)
119

The socio-economic impact assessment of Lower Gweru Irrigation Scheme in Gweru Zimbabwe

Dube, Kaitano 11 1900 (has links)
M.Sc.(Geography) / This study aimed at examining the social and economic impact of rural irrigation schemes with a particular focus on the Lower Gweru Irrigation scheme. The general objective of this study was to assess if rural irrigation schemes can act as livelihood security assets in transforming rural livelihoods, reduce poverty and attain food security in light of climate change. Results are based on findings from self-administered questionnaires directed at farmers and irrigation stakeholders, and face to face interviews involving farmers and stakeholders. Using Statistical Package for the Social Sciences, Microsoft excel and Health 24 web BMI calculator it was concluded that; Lower Gweru schemes, is a source of livelihood security securing food security, reduce poverty and creates rural employment. Regardless of various challenges faced by rural irrigation farmers, irrigations act as poverty and climate change buffers, providing an opportunity for communities to raise their Human Development Index and attain sustainable development. / Department of Geography
120

Efficiency implications of water markets in the lower Orange and Crocodile rivers, South Africa.

Gillitt, Christopher Glen. January 2004 (has links)
Irrigation farmers in the Lower Orange (Kakamas and Boegoeberg) and Lower Crocodile rivers (between Nelspruit and Komatipoort) areas in South Africa were surveyed during October 2003 in order to study whether water marketing has promoted efficiency in water use. This study is a follow-up on research undertaken by Armitage (1999) in the Lower Orange River area and Bate et al. (1999) in the Lower Crocodile River area. Factors associated with future investment in irrigation farming were also studied in the Lower Orange River Irrigation Scheme. Econometric procedures used included principal component analysis, and logit and ridge regression. Results from the two areas will be discussed separately. Econometric results for the Lower Orange River farmers indicate that purchasers of water rights produce lucrative export grapes and horticultural crops with relatively less raisin, wine or juice grapes and less field crops; are more specialised in production (table grapes); have more livestock (probably liquidity factor) and have a less negative view of the five-year water license review period. The water market has facilitated a transfer of water use from relatively lower value crops to relatively higher value crops, and also promoted the use of more advanced irrigation technology. An investment model using Ridge Regression indicates that the following variables are associated with increased future investment in irrigation farming; higher expected profitability and lower levels of risk perception and risk aversion (Arrow/Pratt). Results confirm that farmers who are more risk averse are likely to invest less in the future as can be expected from theory. Policies that increase risk in agriculture will have a significant negative effect on future investment in irrigation. What is significant from the results is that irrigation farmers in the Lower Orange River area are highly risk averse (down-side). Results also show that farmers who feel that water licenses are not secure expect to invest less in the future. The latter effect is thus amplified, as farmers appear to be highly risk averse. This has important policy implications, and measures should be taken to improve the perceived security of water licenses. This could be achieved by keeping farmers more informed about the practical implications of the New Water Act (NWA) (Act 36 of1998) and, specifically, water licenses. In the Lower Crocodile River area, almost all the water trades (permanent and rentals) observed in this study were from farmers above the gorge to farmers below the gorge. It is concluded that in the transfer of water some attributes in the purchasing area such as lower production risk (sugar cane) and lower financial risk and better cash flow (bananas and sugar cane) were more important than the expected income per cubic meter of water. Water supply in this area is highly irregular, while sampled farmers were again found to be extremely risk averse especially as far as down-side risk is concerned. The average water price in this area in recent years (2002 to 2003) was between R2000 and R3000 per ha (l ha = 8000 cubic meters). Buyers have large farms and are progressive farmers that purchase (and rent) from many sellers (or lessors). It is concluded that information on water transfers (sale prices and rents) is asymmetrical. Few permanent transfers have taken place in the Crocodile River in recent years. It is concluded that there are reasons why transfers at present are not processed, such as excess demand for water (due to the irregular flow of the Crocodile River, and role players should discuss these reasons and possible solutions before further action is taken. / Thesis (M.Sc.Agric.)- University of KwaZulu-Natal, Pietermaritzburg, 2004.

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