PhD. Theses and Dissertations

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Determination of Factors Influencing the Efficiency of Legume Green Manures for Maize Production in Embu, Kenya
(Kenyatta University, 2008-05) Gitari, Josiah N.
Land productivity in the central highlands of Kenya is mainly constrained by low and declining soil fertility. In the maize-based farming systems, continuous cultivation without adequate soil fertility enhancement measures has led to a deterioration of land quality resulting in low agricultural yields and degraded soils. Herbaceous legumes can provide an alternative to commercial fertilizers and animal manures. This study explored the use of these legumes in Embu District - situated within the central highlands of Kenya. In order to achieve this objective a survey and four field experiments were conducted to: (1) Validate farmers’ knowledge and practices in soil fertility and use of plant residues; (2) Determine the performance of maize and green manure herbaceous legumes under different intercropping densities and relay-cropping regimes; (3) Investigate the relative efficiency of different legume residue management techniques and determine the need for mineral nitrogen (N) supplementation and (4) Determine the role of low quality plant residues as agents for slowing down the fast-decomposing legume residues to improve N synchrony for maize growth. The study consisted of one survey and four on-station field experiments. The survey involved a total of 134 small-scale farmers cutting across 5 major agro-ecological zones of the 30 km transect of the district. About 87 per cent of all the farmers in the district were affected by the problems of low soil fertility in their farms. Farmers gave soil colour and structure as some of the visual soil fertility assessment indicators used to determine soil fertility status in their farms but the most pronounced and elaborate local indicators seemed to be the dominance of certain weed flora. Soil pH and exchangeable bases (Ca++ and Mg++) were the most sensitive laboratory soil parameters that corroborated farmers’ perceptions and knowledge of soil fertility. Results of the field experiments showed that it is feasible to intercrop maize with any of the three green manure legume species, namely, mucuna [Mucuna pruriens (L.) DC. Var. utilis (Wright) Bruck], crotalaria [Crotalaria ochroleuca G. Don] and lablab [Lablab purpureus (L) Sweet cv. Rongai]. Relay-cropping these green manure legumes (GML) beyond the second week after maize emergence had a significant reduction on legume biomass production possibly due to reduced photosynthetically active radiation (PAR) under the maize canopy. Intercropped GML intercepted less than 30 per cent of the total incident radiation. Nonetheless, intercropping of maize and GML greatly improved land productivity giving relative yield total (RYT) values of between 1.0 and 1.5. Incorporation or surface mulching of the GML residues gave similar maize yield responses that was about double that of the control (no residues). Supplementation of the GML residues (raised in situ) with mineral N was only beneficial if the quantities incorporated were below 2.0 Mg ha-1 . Maize grain yield after mucuna, crotalaria and lablab residues alone (no mineral N supplemented) was 2.5, 2.3 and 1.6 times higher, respectively, than those of the control. Soil N mineralization reached a peak 4 weeks after planting (WAP) and declined thereafter until 8 WAP before picking up again for the remainder of the season. Seasonal mineral N levels ranged between 40 to 128 kg N ha-1 . Plots treated with GML residues gave significantly higher total N uptake than the untreated plots. Over the 3 year period, legume residue incorporation resulted in a slight reduction (0.9-1.8%) in soil bulk density, a small increase in the soil total N but no change in the soil pH. Addition of low quality residues (maize stover) to any of the three GML residues did not affect N release but appeared to enhance their performance. Soil mineralization and maize N uptake was not affected by the addition of low quality residues to the GML residues but resulted in a small increase in the total soil N and pH. However, addition of large quantities of these low quality residues (6.0 Mg ha-1 ) significantly increased the soil organic carbon by 13 per cent and also decreased the soil bulk density by 8.3 per cent when compared to the absolute control with no residues added.
Microbial Diversity of Lake Elmenteita, Kenya
(Jomo Kenyatta University of Agriculture and Technology, 2009) Mwirichia, Romano K.
The major goal of microbial ecology is to understand microbial diversity in natural habitats their interaction with one another and with their habitat. The soda lakes are highly productive environments and the soda lakes of the East African Rift valley have been shown to support a dense and diverse population of aerobic, organotrophic, halophilic, alkaliphilic and alkalitolerant representatives of major bacterial and archaeal phyla. The isolation and characterization of organisms belonging to widespread but previously uncultivated groups of organisms can provide insights into the roles and functions of these organisms in their natural settings and assist in the formulation of hypotheses about metabolic interactions between microorganisms and their natural environment. Several studies have been carried out to document the microbial diversity of the Kenyan soda lakes by other researchers. However no comprehensive study has been done in Lake Elmenteita. The aim of this study was to assess the microbial diversity of Lake Elmenteita using both culture independent and culture dependent techniques. The application of both techniques was expected to provide new insights into the microbial diversity of the Lake as well as possible roles played by each group within the soda lake environment. Application of molecular tools to study microbial ecology has widened our approximation of diversity in the environments. Clone Libraries were constructed from PCR amplicons from total environmental DNA. Primers specific for Bacteria and Archaea respectively were used. Partial sequences were generated for both the clones and the isolates. The relatedness of the Lake Elmenteita bacterial rRNA sequences to known rRNA gene sequences was determined by BLAST analysis and by alignment to the sequences on the ARB database (Release, 1994). Clones possessed a higher similarity to other environmental clones than to cultured microorganisms. A total of 655 clone sequences were sequenced. Of these 525 (80.15%) sequences were related to uncultured members of the Domain Bacteria. This indicates that a large proportion of deep phylogenetic groups are represented in the clone libraries. Sixteen percent of the clones had similarity values below 90% to both cultured and uncultured microorganisms. Forty three percent of the clones had similarity values between 90-95% as compared to 34.35% that had values between 96-98%. Only a mere 6.87% had values between 99-100%. However a number of factors including relatively low cell numbers of large organisms and a variable number of rRNA operons among organisms, as well as extraction and PCR bias, may lead to under-representation of phylotypes relative to their in situ abundance. Cultured isolates are still very important in developing our understanding of bacterial physiology, genetics, and ecology. Isolation was done using both nutrient rich and nutrient poor media. A polyphasic approach was employed in the identification of the various strains. The majority of the isolates (36.75%) belonged to the genus Halomonas while 31.35% belonged to the Genus Bacillus. More than half of the isolates (59.45%) belonged to the Gammaproteobacteria. An overlap between the clone library and the isolates was observed in the Order Bacillales and the Actinobacteria only. In this study novel isolates related to Marinospirillum, Idiomarina, Streptomyces, _ocardia, Marinilactibacillus, Amphibacillus and Vibrio were recovered. A polyphasic approach to characterization showed they represented novel taxa. The study showed that the application of both culture dependent and culture independent methods gives a better picture of diversity in the environment. It can be concluded the soda lakes harbour novel uncultured groups of microorganisms and most of them are of biotechnological potential. Future work should focus on Archaeal diversity as well as the uncultured groups of bacteria.
Empirical and model derived respiration responses to climate in different soils of an arid South African ecosystem
(The University of the Western Cape, 2009) Nyaga, Justine M.
This study examined the magnitude of soil CO2 efflux in an arid South African ecosystem, the flux responses as well as those of key limiting nutrients to soil temperature increases and moisture reductions consistent with a future climate change scenario, and compared measured soil respiration rates with those predicted with empirically and theoretically-based soil respiration models. Measurements of soil respiration rate, temperature, moisture, N and P contents were conducted monthly over a 12-month period in natural environments and those artificially manipulated with replicated open-top warming chambers (average 4.1oC increase) and precipitation exclusion chambers (average 30.1% decrease in rainfall, 26.2% decrease in fog and dewfall) distributed in five different soil-vegetation units.Measured soil respiration rates were over 3-fold less than those reported for temperate and tropical forest ecosystems with 61.5% of the total soil CO2 efflux contributed by root respiration (derived from the differences between moderately vegetated and sparsely vegetated areas) in moderately vegetated soils. Massive increases (up to 15 times) in soil CO2 efflux occurred during wet phases, but even these large CO2 pulses were only comparable in magnitude with soil CO2 effluxes reported for temperate semi-arid grasslands. There was considerable intra-annual and inter-site variability in the magnitude and direction of soil respiration and N and P responses to elevated temperatures and reduced precipitation levels with poor correspondence evident between soil CO2 efflux and soil organic matter content. Soil CO2 effluxes declined in response to precipitation exclusion by 7.1% over all sites and increased in response to warming by 42.1% over all sites. The large increase in response to warming was assisted by a 7.5% enhancement in soil moisture content due to precipitation interception by the chamber walls and its channelling to the soil surface.Relatively smaller respiration increases in response to warming occurred in moderately vegetated soils, these attributed to soil thermal insulation by the plant canopy cover. Soil P and N contents increased in response to warming by 11.3% and 13.3% respectively over all sites, with soil P declining in response to precipitation exclusion by 5.8% over all sites and soil N increasing in response to precipitation exclusion over all sites by 5.8%. Standard least squares regressions quantified the relationships between soil respiration rate and measured soil physical and chemical properties, and their interactions for each of the 5 soil-vegetation units. These relationships were incorporated in an empiricallybased soil respiration (EMR) model which was compared with a theoretically based generalized soil respiration model (GRESP). GRESP model functions included measured Q10 coefficients at soil moisture contents above field capacity, these assumed reduced by half for dry conditions, and maximum retentive and field capacities of soils. EMR modelled soil respiration rates displayed slightly better correspondence with measured soil respiration rates than GRESP modelled soil respiration rates. This apparent from the higher regression coefficients and lower sums of squared residuals, with EMR model residuals also more closely approximating normal distributions. However, despite the EMR model’s slight superiority, it was concluded that more precise laboratory-based measurements of soil retentive and field capacities and their Q10 coefficients at different soil moisture contents could improve the GRESP model’s accuracy thereby providing a more convenient and uncomplicated means of predicting respiration responses to current and future climates over a wide range of arid soil types
Effects of Selected Media on Novel Portland Pozzolana Cement
(Kenyatta University, 2009-02) Wachira, Jackson M.
Cement is subject to degradation by aggressive media found in the environment. Durability tests are therefore necessary for any cementitious material in a given environment. The work reported in this thesis involved the study of the effects of selected aggressive media on a cement, made from inter-mixing Ordinary Portland Cement (OPC), dried acetylene lime sludge (DALS) and an incinerated mix of reject bricks (BB), spent bleaching earth (SBE) and rice husks. The cement was labelled Portland Combined DALS Cement (PCDC). Initial tests showed that PCDC met the Kenya Standard requirements for Portland Pozzolana cement (PPC). PCDC was subjected to various media which included sea water, distilled water, chloride and sulphate solutions in a laboratory set-up. The experiments were carried alongside OPC, 25 % Pulverised Fuel Ash substituted OPC (OPC + PF A) and commercial Pl'C. The study was carried out in two phases; cement mortar moulded into 100 mm cubes subjected to the media and reinforced mortar cubes subjected to a wet and dry alternate environment of 3.5 % sodium chloride solution. PCDC exhibited continued compressive strength gain in all media except in chloride solutions. PCDC exhibited comparable gain in compressive strength and selected ions intake/leach to PPC in sulphate solutions and distilled water. PCDC exhibited higher strength gain than OPC in distilled water. Except in chloride solutions, PPC exhibited higher strength gain than OPC. In Corrosion tests, the PCDC mortar rebars showed early attainment of active corrosion coupled with higher corrosion rates over a short period of time than OPC as w/c ratio was increased. The PCDC showed a decreased chloride penetration than OPC as w/c and depth of cover increased. PCDC showed the lowest apparent chloride diffusion coefficients. The resistivity of PCDC in the aggressive media suggested that it required greater depths of cover, where reinforcement was to be used, and long term curing to improve on its resistivity. The tests showed that PCDC can be used for general construction work in the tested media in a similar manner to Pl'C,
Bantu and Nilotic Children’s Singing Games: A Comparative Study of their Value Communication
(University of Cape Town South Africa, 2009-07) Weche, Michael O.
This study is based on the premise that Luo and Luhya children’s singing games are creative works that subtly reflect the aesthetics of the two communities. The aim is to critically examine how the performance of the singing games and their texts reflect the aspirations, norms and values of the macro cultures of the two Nilotic and Bantu communities respectively. The sampled singing games include those done in the traditional setting, sung in vernacular and those that are taken from the urban or cosmopolitan settings. Our findings reveal that Luo and Luhya children’s singing games are a significant resource in communicating the values of the two communities. Luo and Luhya children imitate their physical and social environments and dramatize about the aesthetics of the communities. This dramatization reflects both traditional values and the new emerging values that have been necessitated by the introduction of western values, formal education, Christianity and others. In these singing games Luo and Luhya children are able to socialize, learn and also uphold the values of unity and respect for one another. The singing games are significant in the learning process and character development of the children involved in the performance. Luo and Luhya children’s singing games play a significant role in socializing the children in their different societies. The socialization makes the child to be rooted in the aesthetics and aspirations of his/her society. Urban children’s singing games that are sung by Luhya and Luo children reflect the child’s creativity, improvisation and the ability to borrow from various sources. The singing games utilize various sources, including the electronic media, print media and also rhymes from other cultures. Children’s singing games are repertoires of a people’s aesthetics. Apart from directly teaching the participants cultural issues and requirements, the singing games are crucial to the participants’ social and moral development. Luo and Luhya children’s singing games reflect the macro culture of the Luo and Luhya communities respectively and to a great extent the changing values in the Kenyan society. The study also gives some insights arising from the findings that can be of benefit to future researchers. There is need for researchers to focus on children’s singing games as creative works and discover their role in the social and moral development of the child and also find out how these creative works can be used in an educational set up.
Assesing the Drivers of Pollinator and Natural Enemy Community in Pigeonpea and Field Bean Crops
(The University of Reading, 2010-09) Otieno, Mark
1. Arthropods are key components in agro-ecosystems providing critical ecosystem services to crops, such as pollination and natural pest control. The structure and functioning of these arthropod communities can be influenced by farm management practices and the context of the farm within the wider landscape, yet this is poorly understood....
Incidence and Extent of Substance Abuse among Secondary School Students in Nairobi Province, Kenya: Implications for Specialized Intervention
(Kenyatta University, 2010-10) King’endo, Madrine
Substance abuse has become a major challenge in secondary schools in Kenya. A study carried out in Kenya observed that 20% of adolescents aged between 12 and 22 years smoke cigarettes, 9% smoke bhang while 23% drink commercial beer and spirits. This is the age in which most youths are in schools and colleges. The aim of this study was to find out the incidence and extent of drug abuse among secondary school students in Nairobi Province, Kenya. This information is useful in developing specialized educational programs for drug abuse in Kenya. The objectives of this study were: to determine various substances commonly abused by students, assess the prevalence of substance abuse in secondary schools, determine the factors that contribute to substance abuse, students‘ behaviour related to substance abuse and identify the factors that influence students to abuse drugs. An expost-facto research design was employed. The study population comprised of all public secondary schools in Nairobi Province. The sampling was done using stratified sampling to obtain different categories of schools, and the status of each school. The schools were chosen from the strata using purposive and simple random sampling methods. Systematic sampling was then applied to obtain the required number of students, where every tenth student from the admission register was selected. One counselling teacher from each sampled school was selected to participate in the study. The total number of respondents was 525 students and 14 counselling teachers. A separate questionnaire for students and another one for counselling teachers were used to collect data. The instrument‘s validity and reliability was enhanced through a pilot study in two schools within the province and were not included in the main study. Face validity and content validity was used by the researcher engaging colleagues and experts in the school of education. The questionnaires were administered to the respondents by the researcher assisted by four research assistants. The research began after obtaining a research permit from the Ministry of Education. The data obtained was coded and analysed using the SPSS programme for windows. The statistics used for this exercise were mainly percentages, pie charts and bar graphs. However, the stated hypotheses were tested by the use of the chi square. The key findings showed that peer pressure, school and family stress, and drug availability contributed to students‘ drug abuse. It was also found that alcohol was the most abused drug, that boys abused drugs more than girls and that drug abuse was more prevalent in mixed schools than the other categories of schools. The study also found that most students, 81%, who abused drugs did this often. The study concludes that stringent measures should be put in place urgently so as to address the problem of drug abuse. The study recommends a multifaceted approach as a strategy for minimizing the vice in the Kenya secondary schools.
Mapping and managing the spread of Prosopis Juliflora in Garissa County, Kenya
(Kenyatta University, 2011-06) Zeila, Abdi
More than three decades after the introduction of prosopis species in the drylands of Kenya there is now increasing concern about the negative impacts of the plant on the livelihoods of dryland communities and on the ecological integrity of the fragile arid and semiarid lands. The extent of the species coverage in the arid and semiarid lands has, however, not been fully mapped owing in part to the recent nature of the problem. As such the aim of this study was to map out the extent of the spread of the species and propose community-friendly management options for this invasive plant. Geographic information system methodology and satellite imageries (Landsat images from 2000 and 2006), maps and GPS points were the main tools used for this work. Standard spatial statistical analysis procedures were employed using the software Erdas Imagine 8.4 and ESRI ArcView to generate land cover changes associated with prosopis species. The study found that a total of 440 square kilometres were newly colonised between the years 2000 and 2006, with Bura division having the highest area of land colonised at 143km² (33% of total land area). The study also noted that the riverine land use/land cover system was the most infested, with 631km2 colonised. This automatically puts the livelihoods of thousands of pastoralists who depend on the River Tana ecosystem at risk. The study also employed a socio-economic survey that involved the use questionnaires and interviews to ascertain the perceptions of the local community regarding origin, impact and uses of the species. Eighty four per cent of the respondents indicated that prosopis’ presence has had negative effect on the indigenous biodiversity of Garissa through loss of native vegetation. The three major local uses of prosopis were charcoal, fuelwood and animal fodder. The study shows that prosopis is a major environmental problem in the study area through its swift colonisation of strategic grazing reserves and is rapidly colonising new lands. The findings of this study call for commercialising production of prosopis for charcoal burning as a strategic management strategy for the plant. This should be accompanied with the use of efficient kilning technologies. In addition deliberate and pro-active policy changes should be put in place to delineate land specifically for this environmental business. Spread of the plant outside designated areas should be controlled by use of environment-friendly mechanical approaches. This further calls for community capacity building in partnership with key stakeholders like Kenya Forest Service. In this way, prosopis will cease to be a liability and instead contribute to community development through wealth creation.
Being There for the Other: Towards a Phenomenology of Help in Mathematics
(University of Alberta, 2013) Karuku, Simon
A qualitative study, framed within a hermeneutic phenomenological stance, was undertaken to explore and describe the essence of the meaning of help in mathematics from the perspective of high school students. Participants were drawn from seven high schools located in the eastern and mid-eastern regions of Tanzania Mainland. The participants were asked to recall and describe a moment when they either sought or gave help in mathematics. Data were gathered through in-depth interviews and participants’ own written experiential accounts. According to the participants, seeking help in mathematics means seeking change in one’s mode of being in the mathematics life-world, and exhibiting responsive openness to the target of the seeking intention. This means that when students are seeking help, they are looking for someone who would help them experience conceptual change. Giving help, on the other hand, is more a way of being there for the recipient than a kind of doing. Most of the participants recalled and described a moment of seeking or giving the type of help that was ultimately aimed at improving the recipient’s performance in examinations. Accordingly, this thesis underscores the need for the seeking that has epistemological significance; namely, the seeking that is aimed at achieving conceptual understanding. In their lived-experience descriptions, many participants also shared feelings of being neglected and disobliged by their teachers. Although the participants longed for the teacher’s time, presence, attention, concern and care, these longings were not satisfied. This led to feelings of aloneness among the participants, which appear to have acted as an impulse for the participants to seek help in the sphere of peergroup relationships. However, due to the peers’ limitations in their ability to help each other, they felt the need to consult private tutors. As professional helpers, teachers play a critical role in transforming help-seeking moments into pedagogical moments. In this regard, one of the challenges raised in this thesis is the need to recover the notion of teaching as a vocation since in essence, it is those teachers who have been called to teaching that will express their being in and through the act of teaching.
Nutritional contribution of atmospheric deposition to the Strandveld vegetation of West Coast South Africa
(University of Cape Town, 2013-07) Nyaga, Justine M.
Ecosystem nutrient availability depends on the balance between rates of nutrient inputs and losses. Nutrients may be lost through fire and displacement of ash, herbivory, leaching and volatilization. The main pathways through which nutrients may be acquired are weathering of rock and atmospheric deposition. Symbiotic and free-living diazotrophic bacteria and blue green algae also contribute N. In ecosystems with limited occurrence of N2-fixation and occurring on low-nutrient bedrock, atmospheric deposition is the most significant source of nutrients. Nutrients from atmospheric deposition may be of natural or anthropogenic origin, and can be “wet-deposited” dissolved in precipitation and “dry-deposited” when aerosols settle out of the atmosphere onto plant and soil surfaces. Studies on nutrient cycling around the world suggest that nutrient deposition can provide substantial amounts of nutrients to coastal ecosystems, although mineral weathering of rocks can also a significant source. Limited prior work on deposition in coastal areas of South Africa suggests that nutrient deposition could be an important component of nutrient budgets in the Cape Floristic Region. The west coast of South Africa borders a section of the Atlantic Ocean that is highly productive and characterized by strong seasonal winds, rough waters and strong wave action. This area is home to the Strandveld vegetation, which grows on marine-derived soils. Based on this, I hypothesized that marine aerosol deposition is a significant source of nutrients for the vegetation in west coast South Africa. To test this hypothesis, I examined the spatial and temporal characteristics of atmospheric deposition as well as the climatic and ecological characteristics of the area. I measured deposition rates and concentrations of essential plant nutrients (N, P, Na, Ca, Mg, and K) delivered in rain University of Cape Town v and horizontal precipitation. Horizontal precipitation was used to refer to all forms of precipitation deposited horizontally and included fog, windblown aerosols, and horizontal rainfall. I then estimated annual demand for these nutrients in 8 plant species growing in the area and compared them to the deposition rates measured in rain. I also compared nutrients deposited in rain water with those deposited in horizontal precipitation, measured the amounts of NO3 -, NH4 + and PO4 3- held in canopies of the 8 plant species during summer, and estimated the species’ capacity for foliar nutrient uptake. The Strandveld vegetation was found to have relatively high soil and plant nutrient concentrations compared to the rest of the CFR, despite its soils originating as nutrient-poor marine derived aeolian sands. Although N and P fluxes deposited in rain were lower than those measured in other pristine sites around the world, a large proportion of TN (84%) and TP (51%) was organic, pointing to a strong marine influence. The marine origin of N and P is supported by the high base cation fluxes compared to those reported globally. The high proportion of organic N and P, and the high base cation contents was also observed in horizontal precipitation. In this form of deposition, base cation concentrations were highest at the coast and contents declined with distance from the ocean, further supporting a possible marine source. This study also suggests that dust may be an important contributor to the deposition of some nutrients during the winter months, and both marine and terrestrial areas could therefore be important sources of nutrient deposition to this area. Based on leaf litter nutrient losses it was estimated that atmospheric deposition through rain alone could potentially supply 36% and 64% of N and P annual demand, respectively, and over 100% of the annual demand for K and Ca. This University of Cape Town vi suggests a strong marine influence in the supply of these nutrients to the Strandveld soils and vegetation. In addition, plants within the Strandveld vegetation intercepted substantial amounts of moisture and nutrients in their canopies. Species with small leaves intercepted significantly greater quantities of water and nutrients than those with larger leaves. It was also established that all the studied Strandveld plants could take up NO3 –, NH4 +, glycine (as a form of organic N) and Li (a proxy for K) through their leaves. Taken together, these results show that the Strandveld ecosystem of West Coast National Park receives substantial inputs of nutrients from marine aerosols, both in rain and horizontal precipitation. This deposition appears to be a critical source of nutrients in an ecosystem with limited bedrock nutrient supplies. Over the time scale of ecosystem development, atmospheric nutrient deposition combined with other ecological characteristics, such as strong moisture-laden winds, may help explain the unique biogeochemical and biogeographical characteristics of the Strandveld.
Discursive Construction of Masculine Identities in Newspapers Pullout Magazines in Kenya
(Laikipia University., 2014-10) Ngumo, Mugambi Cyrus
The study analyzed the discursive constructions of masculine identities in newspapers’ pullout magazines in Kenya. It examined if there was a disconnect between the way Kenya’s mainstream newspapers’ pullout magazines constructed masculinity and the way the readers of these magazines constructed it. The objectives of the study were: to identify and describe the types of masculine identities that are constructed by lifestyle magazines and determine how these magazines justify or legitimize their construction of these identities; to identify and describe the types of masculine identities constructed by readers of pullout magazines and the language they use to construct these identities; to investigate how readers conform to, negotiate or resist the masculine identities constructed by these magazines, and to find out why readers conform to, negotiate or resist these masculine identities as constructed by pullout magazines. The study adopted a Critical Discourse Analysis (CDA), the social constructionist view of gender and the encoding decoding model as its theoretical framework. Purposive sampling was used since only information rich magazines were relevant. Data was collected from The Nation and The Standard newspapers’ pullout magazines published between February, 2012 and January, 2013. Two weekly pullout magazines were selected from each paper. The Saturday Magazine and Lifestyle were selected from The Nation while Woman Instinct and The Dude were selected from The Standard. Data was also collected from readers. Respondents read the magazines individually, and then held a discussion which was tape recorded in focus group discussions. These readers were drawn from male and female students at Kimathi University College and Kagumo Teachers’ College in Nyeri. The CDA method of analysis was used. To begin with, the analysis of the construction of masculine identities by the magazines not only revealed multiple identities but also contradictory ones at times. The same tendency was manifested by the readers’ construction of male identities. Significantly, the study found out that readers conform, negotiate or oppose pullout magazines’ construction of masculine identities. Additionally, both magazines and readers used different linguistic forms to justify their constructions of masculine identities. The analysis also found out that adopting any of the three positions was informed by different ideologies. The finding that masculine identities are multiple reinforces the argument that there is no normal or abnormal masculinity. Thus, Kenyan institutions such as the family, the school, legal departments, and civil society may need to come up with policies that cater and protect men who manifest identities that do not resonate with hegemonic masculinity.
Organisational Internal Context, Information Communication Technology Infrastructure, Staff Attitude and Implementation of Electronic Project Monitoring Information System in Public Tertiary Institutions in Kenya
(University of Nairobi, 2015) Mburugu, Kirema N.
The study sought to establish the influence of organizational internal context on the implementation of Electronic Project Monitoring Information System (e-ProMIS) in Public Tertiary Institutions in Kenya. The study was guided by eight objectives which sought to establish the extent to which each of the independent variables namely; organisational strategy, organisational structure, organisational leadership, organisational culture and staff capacity influence the implementation of e-ProMIS. The study also sought to determine the joint influence of organisational internal context on implementation of e-ProMIS. The moderating influence of availability of ICT infrastructure and mediating influence of staff attitude between the organisational internal context and implementation of e-ProMIS were also examined. Eight research hypotheses related to the objectives were tested. Pragmatic paradigm to support mixed mode approach was adopted. Cross sectional descriptive survey and correlational research design were used. The population comprised members of staff from public tertiary institutions in Kenya. A sample of 210 members of staff was selected using stratified and simple random sampling techniques. Questionnaire with both open and closed-ended items with Likert-type interval scale anchored on a five point scale was used to collect data. Descriptive statistics were computed for all variables using frequencies, percentages, arithmetic mean and standard deviation. Statistical tools used for inferential statistic were Pearson‘s Product Moment Correlation (r), simple regression, multiple regression and stepwise regression ( ). F-tests were used to test hypotheses in the study. The results revealed that r=0.513 f (3,158) =18.840 at p=0.000<0.05, 1. was confirmed and concluded that organisational strategy had a statistically significant influence on implementation of e-ProMIS. With r=0.558 f (3,158) =23.760 at p=0.000<0.05, 2. was confirmed and concluded that organisational structure had a statistically significant influence on implementation of e-ProMIS. With r=0.544 f (2,159) =33.410 at p=0.000<0.05, 3. was confirmed and concluded that organisational leadership had a statistically significant influence on implementation of e-ProMIS. With r=0.504 f (3,158) =17.892 at p=0.000<0.05, 4. was confirmed and concluded that organisational culture had a statistically significant influence on implementation of eProMIS. With r=0.655 f (1,160) =120.161 at p=0.000<0.05, 5. was confirmed and concluded that staff capacity had a statistically significant influence on implementation of e-ProMIS. With =0.557 f (6,155) =39.272, 6. was confirmed and concluded that organisational internal context has a significant influence on the implementation of Electronic Project Monitoring Information System in Public Tertiary Institutions in Kenya. With =0.557 R2Δ=0.597 f (6,155) =39.272 at p=0.000<0.05, 7. was confirmed and concluded that the strength of the relationship between organisational internal context and implementation of e-ProMIS depends on availability of ICT infrastructure. With =0.546, R2Δ=0.559, f (6,155) = 54.42, β=0.706, p=0.341>0.05, 8. was confirmed and concluded that the strength of the relationship between organisational internal context and implementation of e-ProMIS depends on staff attitude. The study further revealed the relevance of Diffusion of Innovation Theory and Theory of Reasoned Action in studying implementation of electronic based systems. The study highlights the need for staff training on new technologies, provision of adequate ICT infrastructure and staff attitudinal change trainings for effective implementation of new electronic based systems. The study deviated from other studies by empirically showing how organisational internal context influence the implementation of ICT based technologies. The study recommends further research to be conducted to establish the influence of monitoring and evaluation on implementation of e-government systems. Other e-government systems like e-procurement and itax also need to be studied.
Effect of Government Regulations on Factors Hindering Financing of Small Scale Water Investments in Kenya
(Jomo Kenyatta University of Agriculture and Technology, 2015) Kimani, Maina E.
In Kenya, most water utilities have been publicly owned and managed. These utility firms have thus been getting financial support from the government in form of subsidies in addition to the revenue they generate internally. However there has been low level of investment in peri-urban areas by both public and private players creating an investment opportunity. Nevertheless this opportunity is not taken up by small scale water investors hence water scarcity. Many people in these areas do not have access to basic water. The general objective of the study was to determine the effect of government regulations on factors hindering financing of small scale water investments in Kenya. Specific objective of the study was to determine whether cost recovery, investor‘s perceived risk, access to capital and return on investments affect financing of small scale water investments in peri-urban areas in Nairobi Kenya. The study adopted cross-sectional survey research design. A two stage sampling technique was used to obtain a sample population of 150 Small Scale Water Service Providers (SSWPs). The study utilized self-administered semi-structured questionnaire and content analysis for collecting data. Structural Equation Modelling (SEM) and Moderated Multiple Regression (MMR) analysis was used to analyse the relationship between predictor variables and financing of small scale water investments. The findings of the study indicated that government regulation moderates the relationship between predictor variables and financing of small scale water investments. It was recommended that cost recovery should be improved, investor‘s risks should be mitigated and capital should be made available. In order to improve return on investments of small scale water investments, the government should enhance tariff reviews. The results of the study will contribute to greater understanding of various financial constraints that small scale water investors go through in trying to make water accessible to peri-urban population.
Design, fabrication and characterization of an appropriate solar thermal electricity generating system
(2015) Millien Kawira, Erastus
The sun provides an abundant and clean source of energy. However the supply of this energy is periodic following yearly and diurnal cycles, intermittent, unpredictable and it is diffused. Its density is low compared to the energy flux densities found in convectional fossil energy sources like coal or oil. There have been attempts to produce solar thermal power using parabolic trough technology as was demonstrated by Luz Company which built a solar electricity generating station with a power output of 354 MW in USA. Also the largest solar power plants in the world using parabolic trough technology are the Andasol 1 to 3 which are established in Spain. Therefore it was necessary to undertake design and fabrication of a solar thermal electricity generating system consisting of a collector, steam storage system, heat exchanger, turbine and generator as a local solution for power production. The design layouts were done using auto cad. The testing of the steam storage system and the heat exchanger were done using TEMA (Tubular Exchangers Manufacturers Association Standard and ASME (American Society of Mechanical Engineers). Locally produced heat transfer fluids (water, saline solutions, vegetable oils and engine oils) were tested for their suitability in solar power production using guidelines obtained from National Renewable Energy Laboratories. Some of the parameters investigated included mass flow rates, power output, efficiency, steam flow rate, heat absorbed, heat emitted, evaporation ratio, proportion of flash steam, number of heat transfer units among others. The efficiencies of the concentrator when using the heat transfer fluids were in the range of 48.8% to 60.1% for closed collector and in the range of 46.7% to 56.6% for the open collector. The length of complete discharge for the steam storage system ranged from 4.4 hrs to 6.9 hrs. The power output for the heat transfer fluids were in the range of 287.9 W to 467 W. The steam storage was found to have an efficiency of 93.5 % and a thermal capacity of 4.54 kJ. The rate of heat transfer was an average of 68.4 Js-1kg-1 to 46.3 Js-1kg-1. The thermal efficiency for the heat transfer fluids was in the range of 0.85 to 0.66. Available power from the impulse type turbine was 478.4 Watts, isentropic efficiency was 83.5 %, cycle power output was 497.8 W, turbine output was 468.2 Wand gear efficiency was 87.9 % and generator efficiency of 86.9 %. The overall efficiency of the system was 34.97%. Coupling of the steam storage system and the heat exchanger increased the capacity of steam storage to 4.15 KJ, at a maximum temperature of 249.5 °C and at a pressure of 7.2 Nm-2. Coupling of the steam storage system and the heat exchanger increased the capacity of steam storage to 4.15 kJ, at maximum temperatures of 249.5 °C and at a pressure of 7.2 Nm-2. A single stage impulse turbine was fabricated which had an average efficiency of 61.6% and a maximum power output of 498 W. The solar thermal characterization and collection was done in solar intensities of the average range 700 Wm-2 to 1100 Wm-2. In Coolidge irrigation facility, a thermocline storage tank has a capacity of 19.8 GJ and operates at a temperature of 288 °C. The thermal capacity of the storage system used in this study was 4.15 kJ and was operating at a temperature of 249.9 °C.
Studies on Potassium requirements for maize in Nyamira County, Kenya
(2015-03) Muthengia, Jackson M.; Kenyanya, Omanga
In Kenya, Maize is a key cereal crop and a major staple food in most Kenyan families. Most maize farmers mainly apply nitrogenious and phosphorous fertilizers to improve on maize yields in the country and Nyamira county in particular. However, acreage yields have been declining yearly despite their use. Application of potassium (K) fertilizers in the regionis limited yet it is the third major nutrient required by maize crop in large quantities for optimum growth and yields. Consequently, it is no longer wise to assume that the soils in the region have enough K levels for good growth and yields. The present study was planned to determine the soils nutrient status and evaluate whether K fertilizers use can play a role to improve maize yield in the region. The field experiments were set and conducted in Gachuba location in Nyamira county. Equilibria K concentrations were determined by flame photometry from filtrate of 2.5g soil in 25ml solutions of various potassium concentrations (0, 25, 50, 75, 100, 125, 150, 175, 200, 225 and 250 mgL-1) after string the mixtures for 24 hours to achieve steady state condition. Adsorption data obtained from the various soil solutions of K were fitted into Langmuir, Freundlich, Temkin and Van Hauy equations. The data fitted Best in Freundlich isotherm model and were farther used to calculate acreage doses. Maize was grown under same doses of nitrogenous and phosphorus fertilizer and ten different doses of potassium in plots of 6m by 5m at two farm sites , that is Gachuba (farm site 1) and Kiang’ede (farm site 2). Maize performance with site and dosage aaplication were determined and growth parameters as well as yield parameters recorded. The study found that maize growth parameters of plant height and stem girth and its yield parameters of ear weight, ear length and grain yields increased steadily as potassium doses were increased and reached their optimum values at potassium doses of 155.84 and 144.76 kg ha-1 giving yields of 3315.27kg ha-1 and 3340.50 kg ha-1 for farm sites 1 and 2 respectively. The concentration levels of available potassium in the soils ranged from 57 to 70 mg kg-1 and with a mean value of 60+- 5.542 mg kg-1. The water soluble potassium ranged from 1.8 to 2.2 mg kg-1 and gave mean of 2.02+-0.16 mg kg-1. Nitric acid extracted potassium had a mean of 149+-2.306 mg kg-1. The mean value energy of replacement, was found as -3572+- 44.98 cal mol-1. The study indicated insufficiency of potassium in the soil for optimum maize production in the region. Also, it established that potassium doses significantly affected concentrations of Phosphorus and nitrogen in the tissues. The findings of this research will create awareness the extent to which potassium has been depleted in soils in the region to both farmers and policy makers and hence appropriate action taken. Also, the information is expected to help extension officers and Farmers to use correct K doses for optimum yields.
Contributions of Selected Microsystems to antisocial behaviours among Adolescents in Secondary Schools in Manyatta Sub- County, Embu County, Kenya
(Kenyatta University, 2015-04) Nyaga, Milcah Njoki
Antisocial behaviour is a major challenge in secondary schools in Kenya. It is linked with delinquent behaviour such as truancy, drug abuse and bullying. These behaviours are related to negative interactions with parents, teachers and peers. The individual lives in constant conflict which results in ultimate long time consequences like failing examinations, frustrations and failure in life. The aim of this study was to investigate the contributions of microsystems to antisocial behaviours among adolescents in secondary schools in Manyatta, Embu County, Kenya. The objectives of the study were to establish the extent of truancy, bullying and drug abuse among adolescents in secondary schools and to investigate the contributions of family, class room and peer group factors on antisocial behaviours. The study was grounded on Erikson‟s Psychosocial theory and Bronfenbrenner‟s Ecological theory. The study adopted descriptive survey research design. The target population was 11,329 students from 46 public schools which are either county boarding schools or coeducation day schools in Manyatta, Embu County. Stratified sampling was used to obtain two girls boarding schools, two boys boarding schools and four co-education day schools. The 2,834 Form Two students were purposively sampled because this group was rated the ring leader in Eastern region. The sample of 320 students was obtained through random sampling while eight deputy principals were selected from sampled schools. A pilot study was conducted on 30 form two students selected from the two categories of secondary schools in Embu County.This was to improve the instruments‟ reliability and validity. The data was collected using student‟s questionnaire, deputy principals‟ questionnare, records analysis and an observation schedule in all the sampled schools. Both descriptive and inferential statistical procedures were used to analyse the data. Chi-square tests were used to determine the significance of association between the independent and dependent variables. The findings revealed that all the classroom factors: academic performance, individuals responsible for discipline, common disciplinary measures, rating of disciplinary measures and counselling services, were significantly associated with antisocial behaviours.The findings showed that among the family factors; parents‟ supervision, students‟opinion on parenting style, parents‟ employment and sharing with parents were significantly associated with antisocial behaviours, while not living with biological parents was not significantly associated with antisocial behaviours. The study further found out that among the peer group factors; students‟ opinion on an individual student and identification based on informal group were significantly associated with antisocial behaviours, while participation in informal group, sharing problems with peers and characteristic of friends‟ behaviour were not significantly associated with antisocial behaviours. The study found out that truancy was the most common, followed by bullying and drug abuse respectively. The study recommended that all children be given equal supervision as that given to the first born children. The study also recommended peer counselling training to be offered to all students.The counselling services need to be activitated and managed by trained teacher counsellors. The disciplinary measures should be modified in consultation with the students and teachers. Parents and teachers should aim at developing a holistic individual who is socially, intellectually and psychologically fit in the society. The concerted effort of the individual and the stakeholders are important for successful adolescents‟ transition.
Usawiri wa Mwanasiasa wa Afrika Katika Ushairi wa Kiswahili
(Chuka University, 2015-04) Kinoti, Timothy M.
Utafiti huu ulishughulikia usawiri wa mwanasiasa wa Afrika katika ushairi wa Kiswahili. Kimsingi, mtafiti alichunguza jinsi washairi mbalimbali walivyowasawiri wanasiasa wa Afrika kiubunifu kwa lengo la kudhihirisha walivyobadilika kisiasa na kimaadili kutoka enzi za ukoloni hadi kipindi cha siasa za vyama vingi. Utafiti huu ulichukulia kuwa wanasiasa hawa hutekeleza wajibu mkubwa katika maendeleo ya mataifa yao na bara la Afrika kwa jumla. Uafikiaji wa malengo mbalimbali ya maendeleo kama vile Ruwaza ya 2030 nchini Kenya na uimarishaji wa Jumuiya ya Afrika Mashariki kwa kiasi kikubwa utategemea maamuzi ya kisiasa. Madhumuni ya utafiti huu yalikuwa kuchunguza nafasi ya ushairi wa Kiswahili katika uhifadhi wa historia ya mwanasiasa wa Afrika; kubainisha sifa za mwanasiasa wa Afrika kabla ya uhuru na kutathmini mabadiliko ya mwanasiasa wa Afrika baada ya uhuru kwa mujibu wa washairi wa Kiswahili. Mtafiti aliichukulia sauti ya mshairi kuwa sauti ya mwananchi ambaye ndiye huathiriwa na maamuzi na vitendo vya wanasiasa. Utafiti huu uliongozwa na Nadharia ya Ulimbwende iliyoasisiwa na William Wordsworth na Samuel Taylor Coleridge na Nadharia ya Baada-Ukoloni ambayo inahusishwa na kazi za Edward W. Said, Gayatri Chakravorty Spivak na Homi K. Bhabha. Utafiti huu ulifanyiwa maktabani ambapo mbinu ya sampuli ya kudhamiria ilitumiwa kuteua data kutoka kwa diwani teule. Uchanganuzi wa kimaelezo ulizingatiwa ambapo mashairi yaliyoteuliwa yalihakikiwa kwa mujibu wa madhumuni ya utafiti. Tasnifu hii imegawanywa katika sura sita. Sura ya kwanza imejumuisha utangulizi. Katika sura ya pili pana mwauo wa maandishi yanayohusiana na utafiti huu pamoja na misingi ya kinadharia. Sura ya tatu imeshughulikia mbinu za utafiti zilizotumiwa katika utafiti huu. Katika sura ya nne na tano, data imechanganuliwa, kuwasilishwa na matokeo kujadiliwa. Hatimaye, sura ya sita inatoa mahitimisho na mapendekezo kutokana na utafiti huu. Matokeo ya utafiti huu yamebainisha kuwa ushairi wa Kiswahili ni utanzu wa fasihi ulio na umuhimu mkubwa katika kuhifadhi matukio mbalimbali ya kihistoria. Kupitia uhifadhi huu, sifa na vitendo vya mwanasiasa wa Afrika vimebainika katika vipindi mbalimbali vya kisiasa. Imebainika kuwa mwanasiasa wa Afrika aliyeonekana kuwa mzalendo kabla ya uhuru alibadilika ghafla uhuru ulipopatikana na kuwa mkandamizaji wa umma alioapa kulinda. Aidha, wanasiasa walioonekana kutetea upatikanaji wa demokrasia ya vyama vingi hawajatekeleza demokrasia hiyo. Licha ya dosari zilizobainishwa na utafiti huu, ni dhahiri kuwa bara la Afrika bado lina wanasiasa wachache vielelezo ambao wanaweza kuigwa na wanasiasa wa wakati huu na wale wa baadaye. Matokeo ya utafiti huu yatawanufaisha wasomi wa Kiswahili, waandishi na washikadau wote wa masuala ya kisiasa barani Afrika na kwingineko ulimwenguni.
Statistical Distributions and Modelling of GPS-Telemetry Elephant Movement Data including the Effect of Covariates
(University of KwaZulu Natal, South Africa, 2015-04) Mutwiri, Robert M.
In this thesis, I investigate the application of various statistical methods towards analysing GPS tracking data collected using GPS collars placed on large mammals in Kruger National Park, South Africa. Animal movement tracking is a rapidly advancing area of ecological research and large amount of data is being collected, with short sampling intervals between successive locations. A statistical challenge is to determine appropriate methods that capture most properties of the data is lacking despite the obvious importance of such information to understanding animal movement. The aim of this study was to investigate appropriate alter- native models and compare them with the existing approaches in the literature for analysing GPS tracking data and establish appropriate statistical approaches for interpreting large scale mega-herbivore movements patterns. The focus was on which methods are the most appropriate for the linear metrics (step length and movement speed) and circular metrics (turn angles) for these animals and the comparison of the movement patterns across herds with covariate. A four parameter family of stable distributions was found to better describe the animal movement linear metrics as it captured both skewness and heavy tail properties of the data. The stable model performed favourably better than normal, Student's t and skewed Student's t models in an ARMA-GARCH modelling set-up. The ex- ibility of the stable distribution was further demonstrated in a regression model and compared with the heavy tailed t regression model. We also explore the ap- plication circular linear regression model in analysing animal turn angle data with covariate. A regression model assuming Von Mises distributed turn angles was shown to t the data well and further areas of model development highlighted. A couple of methods for testing the uniformity hypothesis of turn angles are pre- sented. Finally, we model the linear metrics assuming the error terms are stable distributed and the turn angles assuming the error terms are von Mises distributed are recommended for analysing animal movement data with covariate.
An Evaluation of Effects of Exchange Rate Volatility on Kenya’s French Bean Exports
(University of Nairobi, 2015-04) Mwangi, Samuel C.
During the period after the adoption of a floating exchange rate regime in Kenya, there has been substantial volatility produced by the regime. In spite of the considerable foreign exchange contribution of Kenya’s French beans subsector to the economy, the effects of exchange rate volatility on it remains unclear. This study evaluated the effects of exchange rate volatility on Kenya’s French bean exports to major markets in the European Union. Monthly secondary data for the period January 1990 to December 2011 were used in the estimation of an export demand model. In measuring exchange rate volatility, this study employed the generalized autoregressive conditional heteroscedasticity (GARCH) model. The empirical results show a negative effect of exchange rate volatility on French bean exports and a stimulation of the exports by a shift in the exchange rate regime from fixed to floating. An increase in the level of income in the importing countries led to a rise in the volume of Kenya’s French bean exports while an increase in the relative price led to a decrease in demand in the European Union. From these results, this study recommended that policy makers need to maintain a robust exchange rate regime that will ensure a non-volatile behaviour. Policy measures should be instituted aimed at mitigating the high exchange rate volatility to promote French bean exports from Kenya. In order to cushion exporters from high exchange rate volatility, the government could set up a export stabilization facility and develop forward market for French bean exports. There is need for policy makers to work towards increasing the volume of exports through diversification of market destinations by targeting local, regional and export markets as opposed to the current practice. This can be realized through regional and export market promotion initiatives as well as consistent compliance with quality standards. Innovative ways of meeting the standards and facilitation of smallholder farmers to meet these standards is required. In addition, French bean export promotion incentives such as input subsidies and tax concessions need to be considered. To limit over-reliance on exporting as a major channel for French beans produce in Kenya, the government and key stakeholders in the industry need to be proactive in promoting utilization of French beans locally through value addition and creating awareness to the local consumers on the nutritive value of the vegetable coupled with research and extension initiatives. To reduce the relative price of French bean exports from Kenya, there is need for structural reforms that contribute to increased productivity and the enhancement of international competitiveness.
Design, Fabrication and Characterization of an appropriate Solar Thermal Electricity Generating System
(Jomo Kenyatta University of Agriculture and Technology, 2015-07) Kawira, M.
The sun provides an abundant and clean source of energy. However the supply of this energy is periodic following yearly and diurnal cycles, intermittent, unpredictable and it is diffused. Its density is low compared to the energy flux densities found in convectional fossil energy sources like coal or oil. There have been attempts to produce solar thermal power using parabolic trough technology as was demonstrated by Luz Company which built a solar electricity generating station with a power output of 354 MW in USA. Also the largest solar power plants in the world using parabolic trough technology are the Andasol 1 to 3 which are established in Spain. Therefore it was necessary to undertake design and fabrication of a solar thermal electricity generating system consisting of a collector, steam storage system, heat exchanger, turbine and generator as a local solution for power production. The design layouts were done using auto cad. The testing of the steam storage system and the heat exchanger were done using TEMA (Tubular Exchangers Manufacturers Association Standard and ASME (American Society of Mechanical Engineers). Locally produced heat transfer fluids (water, saline solutions, vegetable oils and engine oils) were tested for their suitability in solar power production using guidelines obtained from National Renewable Energy Laboratories. Some of the parameters investigated included mass flow rates, power output, efficiency, steam flow rate, heat absorbed, heat emitted, evaporation ratio, proportion of flash steam, number of heat transfer units among others. The efficiencies of the concentrator when using the heat transfer fluids were in the range of 48.8% to 60.1% for closed collector and in the range of 46.7% to 56.6% for the open collector. The length of complete discharge for the steam storage system ranged from 4.4 hrs to 6.9 hrs. The power output for the heat transfer fluids were in the range of 287.9 W to 467 W. The steam storage was found to have an efficiency of 93.5 % and a thermal capacity of 4.54 kJ. The rate of heat transfer was an average of 68.4 Js-1kg-1 to 46.3 Js-1kg-1. The thermal efficiency for the heat transfer fluids was in the range of 0.85 to 0.66. Available power from the impulse type turbine was 478.4 Watts, isentropic efficiency was 83.5 %, cycle power output was 497.8 W, turbine output was 468.2 W xxii and gear efficiency was 87.9 % and generator efficiency of 86.9 %. The overall efficiency of the system was 34.97%. Coupling of the steam storage system and the heat exchanger increased the capacity of steam storage to 4.15 KJ, at a maximum temperature of 249.5 °C and at a pressure of 7.2 Nm-2. Coupling of the steam storage system and the heat exchanger increased the capacity of steam storage to 4.15 kJ, at maximum temperatures of 249.5 °C and at a pressure of 7.2 Nm-2. A single stage impulse turbine was fabricated which had an average efficiency of 61.6% and a maximum power output of 498 W. The solar thermal characterization and collection was done in solar intensities of the average range 700 Wm-2 to 1100 Wm-2. In Coolidge irrigation facility, a thermocline storage tank has a capacity of 19.8 GJ and operates at a temperature of 288 °C. The thermal capacity of the storage system used in this study was 4.15 kJ and was operating at a temperature of 249.9 °C.

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