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.

Agriculture is key to New Zealand�s economy with land-use conversions in response to market forces occurring regularly. Recently, high-intensity dairy farming has replaced low-density livestock farming, often degrading surrounding waterways. Of particular concern is that dairy cattle can be a source of the parasite Giardia, which in humans is a common cause of gastrointestinal infection. Thus, this thesis evaluated whether dairy farm conversions posed significant consequences for public health. First I examined the prevalence of Giardia in calves in a rapidly intensifying dairying region of New Zealand. A total of 1190 faecal samples were collected from calves one to seven weeks old during two spring calving seasons and screened by direct immunofluorescent microscopy. Giardia cysts were detected in 31% of samples. To evaluate the potential risk that this environmental source of Giardia posed to the human population, molecular genotyping was used to compare forty Giardia strains isolated from calves with thirty isolates from humans collected in the same region and period. Sequencing the β-giardin gene, Giardia duodenalis assemblages A and B were identified from both hosts, with genotype comparisons revealing substantial overlap of identical genotypes for both assemblages, implying zoonotic transmission. Environmental agencies routinely promote the planting of streamside edges to decrease nonpoint pollution from dairy farms entering waterways. However, current methods for tracking pathogens across farmland and into waterways via surface runoff are limited and typically have been developed using artificially created landscapes. Furthermore, no studies have investigated how Giardia moves across the landscape in farm surface runoff. I developed a field-based tracking method specific for Giardia and used this technique to compare the ability of recently planted vegetation strips with bare soil strips cleared of vegetation at decreasing pathogen concentrations; a typical scenario when planting barriers to reduce waterway contamination. A spike containing a bromide tracer and inactivated Giardia cysts was applied in drip-irrigated surface runoff, with one-minute samples collected from the bottom of the plot. A significant treatment effect was identified for Giardia, with 26% fewer detected in runoff from the planted strip, highlighting the immediate benefit of vegetation planting in removing pathogens. Next I evaluated the effects of four riparian treatments on Giardia runoff: exotic pasture grass and weeds growing in the absence of cattle grazing due to fencing, in comparison to monocultural plantings of three New Zealand native grassland species. Runoff experiments were performed after planting, both prior to and following the main summer growing season. Bromide recovery was high from all four treatments (54 - 99%), with no significant treatment effects. By comparison, Giardia recovery was low (1 - 13%). Prior to summer, two native species reduced Giardia in runoff more than the pasture grass/weed treatment which was almost vegetation-free at this time. After summer, Giardia recoveries were uniformly lower in all treatments. These results demonstrate that after one growing season, fencing waterways produces riparian buffers, via the growth of exotic pasture plants released from grazing, that decrease pathogen concentrations in surface runoff to concentrations indistinguishable from native plantings. Given infectious organisms are known to be in the environment, it is important to assess the risk these pose to human populations. Findings from this research can be used to improve currently available risk-assessment models for Giardia transmission from infected dairy animals via water to humans.

Thesis (MSc Food Sc)--Stellenbosch University, 2013. / ENGLISH ABSTRACT: Over the past two decades, there has been an increase in the use of water sources for irrigation, as well as an increase in Escherichia coli outbreaks linked to fresh produce. The full extent and type of E. coli contamination present in natural water sources is unknown and the contamination sources have also not been confirmed. The aim of this study was to enumerate and characterise E. coli from both irrigation water and potential contamination source sites. Total coliform and E. coli counts found in contamination source sites were as high as log 7.114 and log 6.912 MPN.100 mL-1, respectively. Total coliform and E. coli counts for irrigation sites were lower, with maximum counts of log 5.788 and log 5.768 MPN.100 mL-1, respectively. It was found that more than one third (5/14 = 35.71%) of the irrigation sites had E. coli counts exceeding the guidelines (<1 000 counts.100 mL-1) for ‘safe’ irrigation water for fresh produce (<1 000 counts.100 mL-1) as set by the Department of Water Affairs (DWA) and World Health Organisation (WHO), making the water unsuitable for the irrigation of fresh produce. Phylogenetic subgroups (A0, A1, B1, B22, B23, D1 and D2) and the MALDI Biotyper system (PCA dendrogram) were used to create a fingerprint of each E. coli isolated from the environment. These were then used to link E. coli strains from irrigation water to their most probable contamination origin. Escherichia coli population structure was found in this study, to be better suited for linking E. coli strains from irrigation water to their most likely source, than just applying the phylogenetic grouping. The MALDI Biotyper data in combination with the phylogenetic subgroup assignment was then used to group similar strains and link E. coli from irrigation water to their contamination sources by comparing population structures. Strains isolated from surface and groundwater showed similar distribution patterns, but groundwater strains showed a population structure more indicative of porcine and bovine origin, while surface water showed population characteristics which could not be used to make conclusive links between the irrigation water and suspected contamination sources. When investigating the population structures of individual sample sites, it was found that phylogenetic subgroups A0, A1 and B1 frequently made up the bulk of the E. coli population. It was also found that linking individual irrigation sites to contamination sources was successful, as irrigation site Berg-2 was found to have a similar population structure to contamination source site Plank-1 which represents human pollution from an informal settlement. This led to the conclusion that Berg-2 was being contaminated by human pollution, most probably from an informal settlement. Upon further investigation it was found that Berg-2 is downstream of an informal settlement, proving that E. coli population structure is a successful means of microbial source tracking (MST). Virulence factors of the 153 E. coli isolated during the study were identified and the potential risk associated with using the investigated irrigation water for irrigation of fresh produce, was determined. Two enteropathogenic E. coli (EPEC) strains were isolated from the irrigation water, one from the Plankenburg River water, and the other from a borehole in the Drakenstein area. The latter indicates that borehole water is not as safe as was once thought, and that there are bacterial contaminants finding their way into groundwater. The occurrence of an EPEC strain in river water shows that neither ground nor surface water is guaranteed to be safe, and that treatment of water being used for the irrigation of fresh produce should be implemented. / AFRIKAANSE OPSOMMING: Oor die afgelope twee dekades was daar nie net 'n toename in die gebruik van alternatiewe waterbronne vir besproeiing nie, maar ook 'n toename in uitbrake van Escherichia coli uitbrake wat aan vars produkte gekoppel kan word. Die tipe E. coli-besmetting wat in natuurlike waterbronne teenwoordig is, is onbekend en die besmettingsbron is ook nog nie bevestig nie. Daarom was die doel van hierdie studie om die voorkomssyfer van E. coli van beide besproeiingswater en potensiële kontaminasiebronne te bepaal, asook om die E. coli te karakteriseer. Totale kolivorme en E. coli-tellings wat in kontaminasiebronne gevind is, het ‘n maksimum van log 7,114 en log 6,912 MPN.100 mL-1 onderskeidelik bereik, terwyl die totale kolivorme en E. coli-tellings vir besproeiingswater laer was, met 'n maksimum van log 5,788 en 5,768 MPN.100 mL-1, onderskeidelik. Dit is bevind dat meer as 1/3 (5/14 = 35,71%) van die besproeiingswaterbronne meer E. coli bevat as wat toegelaat word in die riglyne vir "veilige" besproeiingswater vir vars produkte (<1 000 fekale koliforme.100 mL-1) wat deur die Departement Waterwese (DWA) en die Organisasie vir Wêreldgesondheid (WHO) aanbeveel word. Filogenetiese subgroepe (A0, A1, B1, B22, B23, D1 en D2) en die ‘MALDI Biotyper’-stelsel (PKA dendrogram) is gebruik om unieke profiele vir elke geïsoleerde E. coli te skep. Dié profiele is daarna gebruik om E. coli-stamme van besproeiingswater te koppel aan die mees waarskynlike oorsprong van kontaminasie. Daar is in hierdie studie bevind dat die E. coli-populasiestruktuur beter geskik was vir die koppeling van E. coli-stamme van besproeiingswater na hul mees waarskynlikste bron, as net die toepassing van die filogenetiese groepering. Dit was toe gevind dat E. coli wat uit oppervlak- en grondwater geïsoleer is, soortgelyke verspreidingspatrone het, maar grondwaterstamme se bevolkingstruktuur is meer aanduidend van fekale besmetting deur varke en beeste, terwyl oppervlakwater se bevolkingseienskappe nie duidelik genoeg was om ‘n gevolgtrekking oor moontlike bronne van besmetting te maak nie. Toe die populasiestruktuur van die individuele bemonsteringspunte ondersoek is, is daar bevind dat die filogenetiese subgroepe A0, A1 en B1 dikwels die meeste tot die E. coli bevolking bydra. Daar is ook bevind dat die koppeling van isolate in individuele besproeiingswaterbronne met hul mees waarskynlike bronne van kontaminasie suksesvol was. Besproeiingswater van Berg-2 het 'n soortgelyke populasiestruktuur as Plank-1 wat beskou is as ‘n kontaminasiebron. Dit het gelei tot die gevolgtrekking dat Berg-2 heel waarskynlik deur menslike besoedeling beïnvloed word, soos Plank-1, en dat daar moontlik ook ‘n informele nedersetting by Berg-2 betrokke is. Na verdere ondersoek is gevind dat Berg-2 inderdaad ook stroomaf van 'n ander informele nedersetting geleë is, wat bewys dat die E. coli-populasiestruktuur 'n suksesvolle manier is om E. coli kontaminasie te verbind met besproeiingswater. Patogeniese faktore, wat in E. coli voorkom en maagkieme veroorsaak, is vooraf getoets in elkeen van die 153 E. coli-isolate wat tydens die studie geïdentifiseer is. Twee ‘enteropathogenic’ E. coli (EPEC)-stamme is uit die besproeiingswater geïsoleer: een uit die Plankenburgrivier (Plank-3), en die ander uit 'n boorgat in die Drakenstein-gebied (Boorgat A1). Hierdie inligting dui aan dat boorgatwater nie so veilig is as wat voorheen vermoed is nie, en dat bakteriese kontaminasie wel vookom wat nie alleen die grondwater besmet nie, maar ook daarin oorleef. Die voorkoms van die EPEC-stamme in hierdie studie is ‘n aanduiding dat beide grond- en opppervlakwater ewe gevaarlik kan wees, en dat daar dus geen waarborg vir die veiligheid van die water is nie. Die behandeling van grond- en oppervlakwater, wat vir die besproeiing van vars produkte gebruik word, moet daarom ernstig oorweeg word om moontlike uitbrake van E. coli op vars produkte te verhoed.

Orientador: Bruno Coraucci Filho / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil, Arquitetura e Urbanismo / Made available in DSpace on 2018-08-17T23:41:07Z (GMT). No. of bitstreams: 1 Dominato_DanieleTonon_D.pdf: 5136145 bytes, checksum: bc4588de570931c9d0ab9bc99456069f (MD5) Previous issue date: 2011 / Resumo: A escassez cada vez maior de água doce devido ao crescimento demográfico, a urbanização e, provavelmente, as mudanças climáticas, tem dado lugar ao uso crescente de águas residuárias na agricultura. Atualmente, essa prática é uma realidade, principalmente na região sudeste de São Paulo, onde os conflitos pelos usos múltiplos da água são constantes. Frente a essa situação, o objetivo desse trabalho foi avaliar o condicionamento de efluentes sanitários, de um sistema composto por filtros anaeróbios e pós-tratamento por filtros de areia (com espessura de 0,75 m) com altas taxas de aplicação diárias que variaram de 300 a 800 Lm-2, visando reúso agrícola e/ou para lançamento em corpos hídricos. Verificou-se uma remoção na concentração de matéria orgânica em termos de DQO, DBO e COD acima de 90 % no efluente dos filtros de areia em todas as taxas de aplicação estudadas. Os resultados apontam que o parâmetro limitador para a utilização de taxas de aplicação diárias superiores a 700 L m-2 foi a concentração de nitrogênio amoniacal produzido nos filtros de areia, superiores a 20 mg L-1, obrigando a implantação de um sistema de aeração superior. A dosagem de hipoclorito de cálcio empregada para adequar o efluente a legislação foi de 3,25 mg L-1 com um tempo de contato de 45 minutos e a classificação do efluente final para a utilização deste na agricultura foi C3S1, estando apto a ser utilizado com um grau moderado de restrição. Como os resultados foram satisfatórios, comprova-se que é possível a aplicação de maiores taxas hidráulicas nos leitos de areia / Abstract: Increasing scarcity of freshwater due to demographic growing, urbanization and, climate changing are the reason of increasing use of the wastewater in agriculture. Nowadays, this practice is a reality, mainly in São Paulo in the southeast areas, where the conflicts caused by multiples use of water are constant. Based on this situation, the aiming of this investigation was to evaluate wastewater conditioning, from a system composed by anaerobic filters and post - treated by sand filters (0,75m height) with high daily application rates which varied from 300 to 800 L m-2, agriculture reuses and/or discharging into receiving waters. An organic matter removing of 90% in terms of COD, BOD and DOC was observed in sand filters effluent in all application rates which were studied. Results have shown that the limitation parameter to use application rates over 700 L m-2 was the ammonium nitrogen concentration which are produced by sand filters and were over 20 mg L-1, forcing to implant a superior aeration system. Calcium hypochlorite dose, used to make the effluent appropriate according to the law, was 3,25 mg L-1 with a contact time of 45 minutes and the final effluent classification to use it in agriculture was C3S1, which is suitable to be used with a moderate degree of restriction. As the results were satisfactory, higher application hydraulic rates in sand filters are proved to be possible / Doutorado / Saneamento e Ambiente / Doutor em Engenharia Civil

The aim of the work is a vision of changing the approach to the landscape and agriculture. Defining a new field structure and supporting the territorial system of ecological stability. Part of the smart landscape is a series of technological support for agriculture in the form of towers. Subsequently, two of these towers are developed to the scale of detail.

Historically, water, energy and agricultural resources have been naturally scarce in Jordan, but current economic, demographic, geopolitical and environmental conditions are aggravating the situation. The influxes of refugees are increasing the already high natural population growth; better economic conditions and living standards are changing consumption and production patterns; surrounding conflicts affect the supply of resources; and negative effects associated to climate change can be noticed already. Therefore, nexus thinking as a basis for integrated and cross-sectorial natural resources management is essential to achieve water, energy and food security, and eventually to move towards a sustainable development of the country. To that end, understanding the existing nexus interlinkages is crucial. This document constitutes a first nexus approach focused on water, energy and agriculture (WEA) sectors in Jordan. The research has adopted a case study method based on literature review to consider different contextual factors, and three levels of study were regarded: national level, Lower Jordan River Basin within Jordanian borders level, and As-Samra WWTP level, which has constituted the case study. Based on an extensive literature review that has resulted in an updated analysis of the current Jordanian context, the main WEA nexus interlinkages have been identified at every level of study. Thirteen future alternative pathways have been proposed, their potential impacts on WEA nexus sectors have been investigated, and related indicators to evaluate these impacts have been suggested. Additionally, three combined pathways have been analyzed in detail. In general, results show that interdependencies between WEA sectors at all levels are strong and projected to intensify in the future, and highlight the critical situation of Jordan in terms of resource management. Inefficiencies and unsustainable uses of natural resources stand out as decisive problems that urge to be solved, and future pathways appear to be potentially harmful for the Jordanian system unless they are included in an integrated nexus-based planning. / Historiskt sett har vatten-, energi- och jordbruksresurser varit naturligt begränsade i Jordanien, men de nuvarande ekonomiska, demografiska, geopolitiska och miljöbetingade förhållandena förvärrar situationen. Inkommande flyktningar ökar den redan höga populationsökningen; bättre ekonomiska förutsättningar och levnadsstandarder ändrar konsumtion- och produktionsmönster; kringliggande konflikter påverkar utbudet av resurser; och negativa effekter associerade med klimatförändringar är redan tydliga. På denna grund så är Nexus en god grund för integrerad och tvärsektoriell förvaltning av naturresurs och vital för att säkerställa resurser för vatten, energi och mat och eventuellt gå mot en hållbar utveckling inom landet. För att åstadkomma det ovannämnda så är förståelse för nuvarande nexus samband avgörande. Denna studie utgör ett tillvägagångssätt för en nexus studie med fokus på vatten, energi och jordbruk (WEA) sektorerna i Jordanien. Arbetet utgår från en fallstudie och baseras på en litteraturstudie som är gjord på tre olika nivåer: nationell, Lower Jordan River Basin inom gränserna av Jordanien och As-Samra vattenreningsverk, sistnämnda utgör fallstudien. Baserat på en omfattande litteraturstudie som resulterat i en uppdaterad analys av Jordaniens situation, så har de huvudsakliga WEA nexus sambanden identifierats för varje nivå. Tretton framtida alternativa utfall har föreslagits, deras potentiella påverkan på WEA sektorerna har undersökts och relaterade indikatorer har föreslagits för att utvärdera deras påverkan. Vidare, tre kombinerade utfall har utvärderats i detalj. Överlag så visar resultaten på starkt ömsesidigt beroende mellan WEA sektorerna på alla nivåer och är beräknad att intensifieras i framtiden, vilket betonar den kritiska situationen Jordanien befinner sig i med avseende på naturresurshantering. Ineffektivt och ohållbart utnyttjande av naturresurser står ut som ett stort problem som kräver en lösning, och framtida utfall tycks vara potentiellt skadliga för Jordanien om de inte inkluderas i en integrerad planering baserat på ett nexus tillvägagångssätt.

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

PhDRDV / Institute for Rural Development / Throughout the world, irrigation is appreciated because of its immense contribution to agricultural production, food and nutrition security, combating poverty and enhancing development, especially in rural areas. The worsening effects of climate change on rainfall patterns as well as food and nutrition insecurity in sub-Saharan Africa are elevating the importance of irrigation schemes in smallholder farming. However, studies conducted in sub-Saharan Africa indicate that the performance of irrigation schemes remains suboptimal. In addition, the studies are highly skewed towards technical and physical dimensions of the schemes and ignore social aspects such as gender. Consideration of gender imperatives would help define and structure who uses water, when and how. This situation necessitated carrying out the PhD thesis research, aiming to explore and explain inherent gender dynamics in water use and management. The ultimate aim was to propose intervention strategies anchored on differential gender power dynamics embedded in irrigation water use in smallholder irrigation schemes. Specific objectives adopted for the study of the Nyanyadzi irrigation scheme in Manicaland Province of Zimbabwe were to: 1) assess the gendered nature of irrigation water use; 2) determine the gendered nature and extent of participation of male and female members of the irrigation scheme in water management; 3) identify the gendered challenges and constraints to irrigation water use; and 4) propose strategies for improved access and management of water. An exploratory sequentially integrated mixed method research design was used in the two phased PhD studies. Seventy three farmers (26 men and 47 women) were the respondents in the first phase in which qualitative data were collected. The gender analysis matrix and activity profile were used to gather and document the perceptions of men and women farmers relating to use of irrigation water. One hundred and nine conveniently sampled respondents (47 men and 62 women) were the source of data in the second phase of the study, which was quantitative and confirmatory in nature. A questionnaire, requiring responses on a Likert-type scale ranging from 1 (strongly disagree) to 5 (strongly agree) was used to collect data. Qualitative data collected during the exploratory phase were analysed using the Cresswell (2013) Thematic Content Analysis technique. Pair-wise ranking was conducted to determine the major constraints to access, use and management of irrigation water. The Predictive Analytics Software Statistics 18 for Windows (PASW Inc: Chicago, IL, USA) was used to analyse quantitative data. Gender, age, marital status, location of irrigation plot, plot ownership and level of education were the independent variables used. Dependent variables included nature of water use, participation in water management and constraints to water use. Cross-tabulation was carried out and the iii Pearson’s Chi-square test for association used to establish if relationships existed between variables. Statistical significance was considered at P < 0.05. The Cramer’s V post-hoc test was performed to measure the strength of association of the perceptions which the Chi-square test had determined to be significantly different. The uses of canal water were found to be varied and gendered. More women than men used canal water for reproductive purposes such as laundry and bathing. Highly significant positive associations (P < 0.01) were observed among gender, age, marital status, ownership of irrigation plot and level of education with use of irrigation water for laundry, bathing, livestock watering and other communal uses. However, location of plot was not associated with different types of water uses (P > 0.05). With respect to farmers’ participation in meetings, contributing in meetings, repair of canals, provision of labour in canal maintenance, hiring labour for canal maintenance and contributing cash for canal repairs and maintenance, highly significant positive associations (P < 0.01) were observed with gender, age, marital status, level of education, and ownership and location of irrigation plot. Level of education of the farmer was observed to be not associated with his/her attendance of meetings (P > 0.05). Plot location was negatively associated with participation, provision of labour for maintenance, contribution of cash and hiring labour for canal repairs (P > 0.05). Exorbitant payments for using water were regarded as the major constraint to performance of the smallholder irrigation scheme. Highly significant positive associations (P < 0.01) were observed between gender and plot location, and all the constraints to water use that the farmers identified. The constraints ranged from unequal water distribution between and within men and women, and upstream and downstream farmers; unfriendly water delivery times; conflicts and corrupt practices in water distribution; and discrimination with respect to schedules of delivering water. Overall, gender imbalance in the use and management of irrigation water existed. This was evident in the disparities in uses and users of canal water that followed gender and social lines. Men dominated decision making in water management, especially in meetings. In contrast, women dominated in implementation stages mainly in relation to provision of labour for cleaning and maintaining water canals. Considering all the results obtained in the current study, it can be concluded that a combination of socio-economic and socio-cultural factors caused the water problems that the Nyanyadzi irrigation scheme experienced. The need for introducing gender-sensitive interventions in use and management of irrigation water was evident. Thus, gender needs, roles and responsibilities should be reconceptualised so as to align them with the socio-cultural context of the Nyanyadzi community. In addition to this, the fact that both men and women iv are not homogeneous interest groups should be factored into irrigation water management. Lastly, it is crucial to incorporate various social hierarchies that interact with gender to influence irrigation water use and management. How this can be done deserves further scientific investigation. / NRF

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.

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.