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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

Voorsiening en benutting van landbouwater in die Ohrigstad-vallei

January 1999 (has links)
M.Sc. / Because of South Africa's high rate of population growth, it becomes more difficult to supply in the basic needs of people, of which water for personal use and food may be the most important. South Africa is a dry country with weak and marginal soils in most parts. This necessitates the effective use of these important natural resources. Recent legislation forces commercial agriculture to use care and sustainable methods in their resource use. Justification must also be made for ratio of resources used compared to the product delivered from that use. Therefore it is necessary to examine this use and the role it plays in the supply of basic human needs as well as economic growth. A study of these agricultural resources cannot be undertaken on a large scale, because every agricultural is unique. The purpose of this study is to generate an idea of the physical and agricultural environment of the Ohrigstad valley. This research is mostly based on the assimilation of previous studies and the comparing of results over time. This information is used to compare results from previous studies and to determine possible trends in factors_such as rainfall. A further study of the natural resources that attribute to effective commercial agriculture are made. From here the emphasis falls on the use and distribution of irrigation water to these activities in the valley. These natural sources of water and their means of distribution are studied and described. Rainfall as a direct source of water is determined by information regarding rainfall and microclimatic circumstances. Surface and subterraneous sources are described by information on the general hydrology and geohydrology of the study area. In such an environment there are many factors affecting the supply of water to agriculture such as: forestry, afforestation of riparian zones, as well as geological occurrences in the streambeds. Possible solutions for problems posed by these factors are discussed in relation to previous studies in similar areas, as well as the economic benefits that may be reaped because of such change. Finally the role that legislation (Water Act 36 of 1998) plays in the use of water by agriculture is discussed in terms of possible impacts that it may have on commercial agriculture in the area. In this study it has become clear that a lot more research must be done in such a project before any trends can be related and proved.
2

The use of treated effluent for agricultural irrigation in the Bottelary River area: Effluent quality, farmers perception and potential extent.

Rui, Li January 2005 (has links)
The Bottelary River area is located in a Mediterranean climate region, where the agricultural sector plays an important role. During the dry summer season, there is not enough precipitation to meet the agricultural irrigation requirements. Some farmers extract river water which is practically the final treated effluent from the Scottsdene Wastewater Treatment Works to irrigate crops. This research investigated the use of treated effluent for agricultural irrigation in this area, particularly focused on the effluent quality, farmers perception, and the potential extent.
3

The use of treated effluent for agricultural irrigation in the Bottelary River area: Effluent quality, farmers perception and potential extent.

Rui, Li January 2005 (has links)
The Bottelary River area is located in a Mediterranean climate region, where the agricultural sector plays an important role. During the dry summer season, there is not enough precipitation to meet the agricultural irrigation requirements. Some farmers extract river water which is practically the final treated effluent from the Scottsdene Wastewater Treatment Works to irrigate crops. This research investigated the use of treated effluent for agricultural irrigation in this area, particularly focused on the effluent quality, farmers perception, and the potential extent.
4

Assessment of microbial levels in the Plankenburg and Eerste Rivers and subsequent carry-over to fresh produce using source tracking as indicator

Huisamen, Nicola 03 1900 (has links)
Thesis (MSc Food Sc)--Stellenbosch University, 2012. / ENGLISH ABSTRACT: The agricultural sector of South Africa is currently facing a serious water crisis. The decreased availability of water as a result of climate change and the constantly growing population has left many farmers increasingly dependant on surface water as primary source of irrigation. Urbanisation along with out-dated and insufficient wastewater treatment works have all contributed to polluting large volumes of these resources. Consequently, many farmers have been forced to use irrigation water, not only of poor quality, but often water which has been polluted with untreated sewage. As a result, this project aimed at investigating the link between the quality of irrigation water and the impact on the safety of fresh produce. A base-line of the microbial load at three sites along the Plankenburg and Eerste Rivers was established using standard microbial methods for the detection of indicator organisms such as total and faecal coliforms, Escherichia coli and Enterococci as well as potential pathogens that included Salmonella, Listeria, Staphylococcus, endosporeformers and aerobic colony counts. Chemical parameters such as pH, alkalinity, conductivity and chemical oxygen demand (COD) were also monitored, but were not correlated to microbial pollution levels in the rivers. High faecal coliform and E. coli concentrations, ranging from 310 to 7 x 106 cfu.100 mL-1 and 230 to 7 x 106 cfu.100 mL-1, respectively, were detected. The recommended irrigation water guidelines of ≤1 000 (WHO, 1989) and ≤4 000 cfu.100 mL-1 (DWAF, 2008) for faecal coliforms and E. coli were exceeded, indicating faecal pollution and thus a high health risk. This health risk was confirmed when potential pathogens such as Aerococcus viridans, Klebsiella, Listeria monocytogenes and Salmonella typhimurium were detected at all three sites. The carryover of organisms from rivers to produce (green beans and grapes) was investigated by comparing the microbial population of the Plankenburg and Eerste Rivers to the population recovered from irrigation water and the surface of fresh produce. Faecal coliforms, E. coli, Aerococcus viridans, Enterobacter aerogenes, Klebsiella, L. innocua, L. grayi, L. monocytogenes and Staphylococcus aureus were detected in all three sample types, indicating a similarity between the microbial populations found in the river, the irrigation water and produce. Thus, the transfer of potential pathogens from the rivers to produce is a strong possibility. The build-up of organisms on the surface of green beans as a result of multiple irrigations was also confirmed by an increase in faecal coliform concentrations from initial concentrations of none detected to 44 000 cfu.100 mL-1 over a 10 day irrigation period. Finally, microbial source-tracking techniques including multi-antibiotic resistance (MAR) profiling, and the API 20E classification system were used to determine genotypic and phenotypic characteristics of 92 faecal isolates (from irrigation water and produce) and 13 reference strains. Numerical classification systems was used to classify the 105 faecal isolates according to the degree of similarity between the genotypic and phenotypic characteristics of the 105 isolates. A high degree of similarity indicates a high probability that isolates originate from the same strain and therefore from the same source, thereby confirming the transfer of organisms Faecal isolates (93 and 98%, respectively) were found to be resistant to Vancomycin at both the 5 and 30 μg concentrations. The majority of isolates presented some resistance to Erythromycin (15 μg) and Ampicillin (25 μg), with 82% of isolates presenting an inhibition zone ≤4 mm. Isolates were sensitive towards Ciprofloxacin (1 and 5 μg), Ofloxacin (15 μg), Ceftriaxone (30 μg) and Cefotaxime (5 μg), which were able to inhibit the growth of 79.8, 93.3, 79.8, 88.5 and 71.2% of the isolates, respectively. The 13 medical reference strains all presented different genotypic and phenotypic characteristics and thereby indicated a high degree of variability between isolates from the same species. Finally, 35% of the isolates could be grouped together based on similar genotypic and phenotypic characteristics, therefore, more than a third of the faecal isolates obtained from the surface of the fresh produce was as a result of faecal contaminants in the irrigation water. It could therefore be concluded that a health risk is associated with the water from the Plankenburg and to a lesser extent, Eerste River when used as source of irrigation, thereby risking the transfer of potentially harmful organisms, present in the rivers as result of faecal pollution, to the surface of fresh produce. / AFRIKAANSE OPSOMMING: Suid-Afrika stuur tans af op 'n dreigende water krisis. Klimaatsverandering tesame met 'n spoedig groeiende bevolking het gelei tot 'n aansienlike vermindering in die land se varswaterbronne terwyl veranderende reënvalpatrone daartoe bygedra het dat talle boere al hoe meer afhanklik geword het van oppervlakvarswaterbronne as hul hoof-besproeïngsbron. Verstedeliking, armoede asook verouderde en onvoldoende infrastrukture het egter bygedra tot die besoedeling van baie van hierdie oppervlakvarswaterbronne. Gevolglik is meeste boere genoodsaak om klaar te kom met besproeïngswater van, nie net onaanvaarbare mikrobiese kwaliteit nie, maar dikwels water wat gekontamineer is met onbehandelde riool. Hierdie studie was gevolglik daarop gemik om die impak van die mikrobiologiese kwaliteit van besproeïngswater op die veiligheid van vars groente en vrugte te bepaal. Standaard mikrobiologiese metodes vir die bepaling van indikator organismes soos totale en fekale kolivorms, E. coli en enterococci asook potensiële patogene wat Salmonella, Listeria en Staphylococcus insluit, was gebruik om die mikrobiese lading by drie verskillende punte (P1, P2 en P3) in die Plankenburg en Eerste Rivier te bepaal. Chemiese parameters soos pH, alkaliniteit, konduktiwiteit en Chemiese Suurstof Behoefte was ook bepaal maar geen korrelasie kon tussen hierdie eienskappe en die mikrobiese besoedelingsvlakke getref word nie. Hoë konsentrasies fekale kolivorms en E. coli wat onderskeidelik vanaf 3.1 x 102 tot 7 x 106 kve.100 mL-1 en 2.3 x 102 tot 7 x 106 kve.100 mL-1 gestrek het en gereeld die voorgeskrewe riglyne van onderskeidelik ≤1 000 (WHO, 1989) en ≤4 000 kve.100 mL-1 (DWAF, 2008) oorskry het, was by al drie punte gevind. Hierdie resultate het gedui op fekale besoedeling wat gevolglik met 'n hoë gesondheidsrisiko geassosieer kon word. Hierdie risiko was bevestig deur die teenwoordigheid van talle potensiële patogene, soos Aerococcus viridans, Klebsiella, Listeria monocytogenes en Salmonella typhimurium, wat vanaf al drie punte geïsoleer was. Die oordrag van organismes vanaf die besoedelde riviere na vars vrugte en groente (groen bone en druiwe) was bepaal deur die mikrobiese lading in die Plankenburg en Eerste Rivier te vergelyk met dié verkry vanuit die besproeïngswater en vanaf groen bone wat besproei was met hierdie water. Fekale kolivorms, E. coli, Aerococcus viridans, Enterobacter aerogenes, Klebsiella, L. innocua, L. grayi, L. monocytogenes en Staphylococcus aureus was vanaf al drie die monster tipes geïsoleer. Hierdie resultate het gedui op eenderse mikrobiese populasies in al drie bronne en het daarom die moontlike oordrag van patogene bevestig. Die opbou van organismes as gevolg van veelvuldige besproeïngsessies aan die oppervlak van groen bone was bevestig deur die toename in fekale kolivorm konsentrasie vanaf 'n begin telling van nul tot 'n maksimum konsentrasie van 44 000 kve.100 mL-1. Laastens was mikrobiologiese bron naspeurbaarheidstegnieke soos multi-antibiotika weerstandbiedende profiele en die API 20E klassifikasie sisteem gebruik om individuele genotipe en fenotipe profiele van die 105 fekale isolate saam te stel. Numeriese klassifikasie sisteme was gebruik om die isolate op grond van ooreenkomste tussen hul individuele fenotipiese en genotipiese karaktereienskappe te groeppeer. 'n Hoë mate van ooreenkomstigheid sal dan daarop dui dat isolate van dieselfde besoedlingsbron afkomstig is en gevolglik die oordrag van organismes vanaf besproeïngswater na vrugte en groente bevestig. Onderskeidelik 93 en 98% van die fekale isolate het daarop gedui om weerstandbiedend te wees teen beide 5 en 30 μg Vancomycin. Die meerderheid isolate (82%) het ook 'n mate van weerstand teenoor Erythromycin (15 μg) en Ampicillin (25 μg) getoon met inhibisie sones ≤4 mm. Isolate was ook sensitief teenoor Ciprofloxacin (1 en 5 μg), Ofloxacin (15 μg), Ceftriaxone (30 μg) en Cefotaxime (5 μg). Hierdie antibiotikums was in staat om die groei van onderskeidelik 79.8, 93.3, 79.8, 88.5 en 71.2 % van die isolate te inhibeer. Alhoewel resultate 'n hoë mate van variasie tussen isolate van dieselfde spesie getoon het was dit nogtans moontlik om 35% van die isolate saam te groeppeer op grond van ooreenstemmende genotipe en fenotipe profiele. Meer as 'n derde van die fekale isolate wat vanaf die oppervlakte van die groente en vrugte geïsoleer was, was afkomstig vanaf fekale besmetting in die besproeïngswater. Die oordrag van potensieël patogene organismes vanaf besoedelde riviere na vars vrugte en groente tydens besproeïng was sodoende bevestig. 'n Hoë gesondheidsrisiko was gevolglik gekoppel aan die gebruik van water vanaf die Plankenburg Rivier, en in 'n minder mate die Eerste Rivier, as bron van besproeïngswater. / Water Research Commission / National Research Foundation
5

Water resource management for subsistence farming in Ward 19 of KwaZulu-Natal

Bakre, Olayemi Rahman January 2015 (has links)
Submitted in fulfilment of the requirements of the degree of Master of Technology: Governance and Economic Development, Durban University of Technology, Durban, South Africa. 2015. / South African rural areas are amongst the poorest in the world, as there is still a wide gap in terms of development with their urban neighbours. With an estimated 6.4 million South Africans falling below the national poverty line in 2010, KwaZulu-Natal (KZN) remains the province with the highest number of poor people. The majority of rural dwellers in South Africa and KZN rely on subsistence farming, while others depend on government grants or family members living and working in urban areas to sustain a living. However, the income received is often insufficient to cater for their daily needs. In consonance with the high prevalence of poverty and the stagnation of subsistence farming, this study aims to examine the role of water supply in rural agricultural development in the Ward 19 area of Mtubatuba Municipality, which is situated along the north eastern region of KZN. To accomplish this aim, a mixed research approach with elements of qualitative (interviews) and quantitative (questionnaire) research techniques was used to obtain relevant information. A total of 50 participants took part in this study, all of whom were subsistence farmers in Ward 19 of Mtubatuba Municipality in KwaZulu-Natal. Furthermore, interviews were conducted with three senior officials from the regional office of the Department of Water Affairs in Durban; three staff members from the Mtubatuba Municipality; two individuals from Ward 19; two senior staff members from the Department of Agriculture, Environmental Affairs and Rural Development in Mtubatuba; as well as two senior staff members from Umkanyakude water services provider in Mtubatuba. The study revealed that water shortages have adversely undermined the development and growth of subsistence farming in this poor community. Furthermore, the difficulties experienced by the marginalised people of Ward 19 are typical of many rural areas which have not fully benefitted from transformation in a post-apartheid South Africa. In order to address the defunct subsistence iii farming in this community, the study proposed a well-tailored and effective water resource management approach with the intention of transforming subsistence farming into commercial farming, thus improving the standard of living and reducing poverty to a reasonable level. Furthermore, in recognition that the area under study is dominated by women, the study emphasised the imperativeness of empowering the women of the community as a strategy underpinning rural development.
6

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.
7

Assessing the use of wetting front detectors in water management at Dzindi Small Small Scale Irrigation Scheme in Limpopo Province

Maduwa, Khathutshelo 18 April 2017 (has links)
MESHWR / Department of Hydrology and Water Resources / Irrigation uses the largest amount of water, estimating to 60 % of the total consumption in South Africa. For this reason, the efficient and reasonable use of water by irrigators is of paramount importance. Thus, this study was carried out to assess the suitability of Wetting Front Detectors (WFDs) in improving water management. The study involved an on-farm survey; field installations; testing of WFD technology on selected plots within the scheme; identification of the crops grown; documentation of the current water supply and documentation of the challenges faced by farmers in relation to irrigation. These were carried out to identify the ideal situations in the scheme. Irrigation scheduling helps farmers to know when to irrigate and amount of water required supplying for crop need. The study presented WFD, as a means of improving irrigation efficiency. The WFD is a simple tool that helps farmers to identify what is occurring around the root zone. Four plots with a representative farmer in each of the plot were identified in four Blocks (Block 1 farmer 1, Block 1 farmer 2; Block 2 farmer 1; Block 3 farmer 1 and Block 4 farmer 1). On-farm experiment of the WFD was carried out. However, with Block 4 farmer 1, insufficient data was collected due to absence of LongStop equipment. This also involved field installation, observation and measurements of the LongStops (LSs) and FullStops (FSs) WFDs at placement depth of 30 cm, 45 cm and 60 cm. The efficiency of an irrigation system depends on different performance indicators including Irrigation Efficiency (IE), Conveyance Efficiency (CE), Application Efficiency (AE), Storage Efficiency (SE), Distribution Uniformity (DU) and Coefficient uniformity (CU). In this study, attention was focused only on DU; CU and SE, as represented by water moisture availability. All the DU for all plots in blocks were below the standard DU of furrow, which is 65%. Farmer 2, in Block 1, had a higher DU and CU, which were 60% and 68%, respectively- considered closer to the standard DU value. For the other farmers, their DU and CU prior to irrigation were very low, which indicated that there was uneven distribution of water in these plots. The poor DU in Block 1 farmer 1, indicated by the uneven infiltrated water, resulted in excessive watering. Analysing the WFD showed that farmers were performed well in all the Blocks, except for farmer 1 in Block 1. Average soil moisture content result indicated high water loss through deep percolation. The highest volumes of water recorded before and after irrigation were 131 ml and 159 ml, respectively, for LS90 placed at a depth of 90 cm in Block 2 farmer 1. High volumes of water were collected in Block 1 farmer 2, Block 2 farmer 1 and Block 3 farmer 1 before and after irrigation. The result showed that, the more placement depth down the soil profile, the more accumulation of water in the LSs. Therefore, it was recommended that farmers continue to use the WFD as a tool for irrigation efficiency. However, there is need for improvement and capacity building in using the tool.

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