Egerton Journal of Science and Technology

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Longitudinal trends in macroinvertebrate functional feeding groups in a high-altitude tropical stream (A case study of Gura River)

(Egerton J. Sci. & Technology, 2021-08-31) Benjamin, J. M.; Abuya, D.K.; M’Erimba, C.M.

Functional feeding groups (FFGs) classification of aquatic macroinvertebrates is an important tool that enhance the knowledge of trophic dynamics in tropical streams by assigning the benthic community into trophic guilds. The current study aimed at determining the longitudinal trends in macroinvertebrate functional feeding groups in Gura River. Macroinvertebrates were collected between November and December 2018 in seven sites along the Gura River from an altitude of 2977 to 1547 m a.s.l. At the same time, selected physical chemical variable were measured in situ at every site. Dissolved oxygen concentration (mgL-1), water temperature (oC), electrical conductivity (µScm-1), pH and turbidity (NTU) had a significant difference among the sites (p <0.05). Most of the nitrates and phosphate nutrients had a significant difference among sampled sites (p <0.05) except NO2-N as demonstrated by analysis of variance (one-way ANOVA, F (6,14) = 2, p=0.085). A total of 4016 macroinvertebrates specimen were collected belonging to 9 orders and 28 families and assigned into 5 respective FFGs. Overall, Scrapers, dominated by Heptageniidae (Afronurus) had the high relative proportion of FFGs in all the sites with a proportion of 42%. Shredders and Predators were the least represented functional feeding groups with proportions of 6% and 3% respectively. This study is crucial in the Gura River because FFGs can be used as an indicator of aquatic ecosystems change in case there is alteration of ecosystem function due to environmental variables.

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Effects of Macrobends on the Attenuation of Optical Signals in Multi-Mode Graded Index 62.5/125 μm Cable at 850 nm Wavelength

(Egerton University, 2012-10) Chombah, . J.M.; Gwaro, J.O.; Nyaanga, .D.M; Kirui, M.S.K

In fibre optic transmissions, macrobend is a large visible bend in the optical fiber that can cause attenuation, a reduction of optical power in the glass. A relatively large- radius bend in an optical fibre may results to the degradation of the optical signal. In this paper, different magnitudes of circular macrobends in graded index 62.5/125 cable at 850 nm wavelength were used to determine the effect of macrobends on attenuation of signals. A special bending jig was used to produce circular bends ranging from 3mm to 200mm. The insertion method was used while attenuation (signal power loss) was measured in decibels (dB). Statistical analysis software (SAS) at a significant level of 5 per cent (and least significantdifference (LSD) ranking method were used for data analysis. The findings showed that large magnitude of macrobend radii (above 40.0mm) resulted in low attenuation (about 9.0 dB) of signals, while small size bend radii (about 3.0 mm) produced very high (about 40.0 dB ) ofsignal losses. The research findings indicate that macrobends have significant effects on the attenuation of optical signals.

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Epidemiological Factors Determining Clinical Malaria in the Highlands of Western Kenya: Case Study of Iguhu Location

(Egerton University, 2012-10) Essendi, M.W.; Shivairo, R.S.; Muleke, C.I.; Yaw, Afrane; Odhiambo, R.O.

This paper reports findings on the prevailing “epidemiological factors that determine occurrence of clinical malaria in the highlands of western Kenya, a case study of Iguhu location.In this study, the risk factors associated with clinical malaria in western Kenya highlands were evaluated. A simple household survey of existing clinical malaria cases and their age-matched cohorts was undertaken to collect information on the potential exposure factors and prevailing socio-economic status. Mosquito samples were harvested from participants’ houses for identification and cataloging. The differences in parasite and vector populations in clinical malaria cases and controls were determined using the “t-test”. The results showed that sex, age, household population, education level and occupation status of the household head were not significant determinants for clinical malaria in the area of study. These was in contrast, to families whose spouses were employed and educated to tertiary level that exhibited lower infections rates since they had used insecticide treated nets (ITNs) prophylaxis and mosquito prevention measures. These significantly reduced the disease incidence suggesting that socio economic factors played a role in the ailment control. These findings show that clinical malaria incidence in western Kenya highlands is likely to be influenced by both biotic and abiotic factors including parasite and vector densities suggesting that any successful eradication program should be directed towards prevailing local conditions in a given area.

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Effects of Surface Tension over a Flow Past a Flat Plate

(Egerton University, 2012-10) Gathia, P.W.; Lonyangapuo, . P.

We consider a free surface flow past a flat plate. We consider relations between the results of Anderson and Vanden-Broeck (1996) and those of Osborne and Stump (2000), and present new solutions. There is need to know the number of parameters needed to fix solutions uniquely. We show here that there is a three parameter family of solutions when the fluid is of finite depth. These solutions are characterised by a train of waves in the downstream region and by a discontinuity in slope at the separation point. The family includes a two parameter sub-family for which the free surface leaves the plate tangentially. It is shown that this sub-family reduces to the linear solutions of Osborne and Stump (2000) when the depth of submergence of the plate is small. Also, the three parameter family reduces to the one parameter family of Anderson and Vanden-Broeck (1996) as the depth of the water tends to infinity. Finally, fully nonlinear solutions with large capillary waves are presented.

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Determination of Triumfetta tomentosa B. Growth Parameters and Fibre Properties in Kenya

(Egerton University, 2012-10) Kinuthia, . N. L.; Mathooko, . M. J.; Kariuki, T. S.; Mucheke, W.

Triumfettatomentosa B. (Fam. Tiliaceae) is an indigenous perennial shrub growing naturally in moist habitats. It is a multipurpose plant traditionally used by many communities in Kenya as a source of fodder, fiber for baskets and ropes and wood for winnowing trays. However, as population increases, the suitable habitat for the shrub is being converted into agricultural and settlement sites making T. tomentosa an endangered species. Kenya needs a cheap source of vegetable fiber in order to revive its textile industries and make industrialization a reality by the year 2030. Currently Kenya spends about Ksh 20M in imported vegetable fibres. The aim of this study was to investigate methods of cultivating T. tomentosa and processing its fibres. Seeds and cuttings were collected from Mt. Kenya and Karura forests. These were raised in nurseries at Muguga (Kenya Forestry Research Institute - KEFRI). The seedlings were transplanted after attaining about 25-40 cm in height. Three experimental sites including Embu, Meru and Muguga were used for cultivation of T.tomentosa. Random Block Design method was used at spacing of 30 cm X 30 cm and 45 cm X 45 cm in 3 replicates for each plant material. Growth in height and diameter at breath (dbh) was measured after every month until about 50% of all the plants had formed flowers. Others were subjected to retting at Egerton University to release fibres. Fiber properties were tested at Kenya Bureau of Standards (KEBS) in Nairobi, Kenya. Descriptive statistics, Chi-square test of independence and Mann-Whitney U test of significance models were used. Cuttings from Karura had a higher shooting percentage (70%) than those from Mt. Kenya forest (40%). Plants from Embu plot gave the highest fiber yield among the three plots, while tenacity tests showed significant difference between fibres from cuttings and those from seeds. The results showed that it was easier to cultivate T. tomentosa from cuttings. Its fibres were close to those of Jute in tenacity and therefore good for making sacks, ropes and mats.

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Rescheduling Lengthy Downloads on Bottleneck Links

(Egerton University, 2012-10) Odongo, . Y. G.; Rai, . A. I.

TCP’s ability to share bottleneck bandwidth fairly and efficiently dwindles when faced with an increase in the number of competing flows. Indeed studies have shown that long TCP flows consume more than 90% of the available bandwidth, with short flows consuming a very small portion. It is also known that out of these, a very small percentage of the largest flows carry the majority of the bytes. The utilization pattern of bottleneck links exacerbates this situation. During the daytime (peak period), the network utilization is characteristically high whereas at night (off-peak period), the link is virtually idle. At peak periods, TCP’s congestion control mechanisms highly favour long-lived flows at the expense of their short-lived counterparts. We discuss the design and implementation of a flow rescheduling tool. The tool identifies, blocks and reschedules long flows to reconnect during the off-peak period. Network bottlenecks are a commonplace phenomenon in many IP networks just as much as they are unavoidable. TCP’s ability to share bottleneck bandwidth fairly and efficiently dwindles when faced with an increase in the number of competing flows. Indeed recent studies have shown that long TCP flows consume more than 90% of the available bandwidth, with short flows consuming a very small portion. It has also been realized that out of these, a very small percentage of the largest flows carry the majority of the bytes. The utilization pattern of bottleneck links does not make matters any better. During the day, the utilization pattern is characteristically high whereas at night, the link is virtually idle. We refer to these times as the peak and off-peak periods respectively. At peak time, TCP’s congestion control mechanisms highly favor long-lived flows at the expense of their short-lived counterparts. This work discusses the design and implementation of a flow rescheduling tool, specifically illustrating the techniques used to achieve accuracy and robustness. The tool works by identifying and rescheduling long flows to reconnect during the off-peak period, when link utilization is very low. We present validation results for the tool which demonstrate its reliability in the face of actual Internet conditions.

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Farmers Perception and Adoption of Drought Tolerant Wheat Varieties in the Arid and Semi-arid Lands of Kenya

(Egerton University, 2012-10) Ndiema, . A. C.; Aboud, . A. A.; Kinyua, .M.; Keya, N. C. O

Wheat is an important cereal crop in Kenya and ranks second after maize in its cereal crop priority grown mainly in highlands parts of the country. About 20% of the country is classified as medium to high potential land ideal for wheat production. The limited ideal land for crop production has forced farmers to extend production in to the arid to semi-arid areas. Drought tolerant wheat varieties (DTV) have been developed for the Arid and Semi Arid Lands (ASAL) but adoption is generally low. Production has therefore lagged behind in meeting national demand resulting in importation in order to bridge the gap. This study was therefore designed to describe and determine farmer perception and adoption of drought tolerant wheat varieties by assessing socio-economic factors influencing adoption of DTV in the (ASALs) areas of Kenya. A sample size of one hundred and eight (108) wheat farmers from Ololung’a division of Narok and Isinya division of Kajiado districts respectively were randomly selected. The collected data was analyzed using SPSS version 12 for windows. Descriptive statistics like frequency distribution and inferential statistics like Chi-square and T-test were used. Farmer perception on drought tolerant wheat varieties was very low (0.9%) with majority of the farmers (77.8%) being uncertain of the objective of drought tolerant wheat varieties as a technology and its benefits. Eighty seven point nine percent (87.9%) of the farmers identified input cost as a major constraint and 85.1% lacked the relevant information. Opportunities for adoption cited by 91.6% of the respondents included the availability of the appropriate technology. There was no significant difference in perception between the farmers of Narok and Kajiado districts. However, there were significant differences in adoption levels by farmers with the average percentage for Narok mean of 1.58 being higher than Kajiado mean of 1.33 with a t-test value of -2.497; (P<0.014; α=0.05. Age, gender, and education did not have any statistical significance relationship in the adoption of DTV but farm size, land tenure system and extension Farmers Perception and Adoption of Drought Tolerant Wheat91Egerton J. Sci. & Technol. Volume 12: 90-99ISSN No. 2073 - 8277 services were statistically significant. It is therefore recommended that extension services be given great emphasize in the ASAL of Kenya.

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Reproduction Inhibition Effects of Neem Products on the Larger Grain Borer (Prostephanus truncatus)(HORN) in Stored Maize Grains

(Egerton University, 2012-10) Ogemah, .V.; Reichmuth, .C.; Buttner, . C.; Ayiecho, .P.O; Keya, .N.C.O.

The larger grain borer (LGB), Prostephanus truncatus (HORN), has become one of the most important insect pest of stored maize in tropical Africa where it was introduced in the early 1980s. It has the major effect of seriously damaging dry stored maize grains and so increasing post-harvest losses and contributing towards food shortage in this region. Losses of up to 85% by weight and 100% by food value have been reported. A study was conducted to investigate the effects of two neem products, neem oil and NeemAzal® powder on egg laying, hatching, larval development and adult emergence of the pest on shelled maize. Treatment of the grains with sub-lethal dosages resulted in 76.3% and 0.6% reduction in egg laying by neem oil and NeemAzal®, respectively. No adults emerged from samples treated with 0.3 and 0.6% w/w NeemAzal® and ca 2% v/w of neem oil. Generally, neem oil reduced the progeny population more than the adult population, the contrast of which was true for NeemAzal®. When the grains were treated after oviposition, no progeny emerged in neem oil samples while 4.4 and 20 larvae, 3.4 and 27.8 live adults and 17.6 and 1.4 dead adults were observed in NeemAzal® and control samples, respectively. The grain weight loss recorded was significantly lower for neem oil than for NeemAzal®. The two products have different effects on LGB, neem oil being effective in controlling early stages while NeemAzal® is more effective in controlling the adults. It can therefore be concluded that the effect of the neem products used in this study on LGB depended more on the formulation than on the content or dosage of azadirachtin used. The results of this study will help refocus research on the control of LGB towards design of appropriate formulations of neem products, which will make them useful in the control of the management of LGB by small scale, resource poor farmers in Africa.

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Design and Application of Bio-economic Modelling in Livestock Genetic Improvement in Kenya: A Review

(Egerton University, 2012-10) Muhehe, D. J; Muia, M. L; Ogola, .W.

Bio-economic modelling in livestock production systems presents the opportunity for incorporating some elements of human decision making and simulates the impact of such decisions using mathematical relationships produced from biological and economic parameters. This paper has reviewed the processes of bio-economic modelling as applied to livestock genetic improvement especially in simulating profitability of alternative enterprises as well as estimation of biological and economic weights. A collection of country specific bio-economic models developed for different species of livestock have been critically analysed in describing their design and application. Participation of target group farmers in design and implementation of the models with respect to their reliability has been presented. It is found that most models were generated from animal life-cycle on farm while considering animal age groups, biological and economic parameters influencing revenues and costs. The differences in the level of participation closely related to the production system of target farmers. Bio-economic models have remained a tool for professional animal breeders with little extension of the technique to fit farmers’ preferences. In most cases, livestock farmers had very little control of the estimates of parameters generated from bio-economic modelling. Farmer-based option (accounting for risks) of bio-economic modelling could increase acceptability and utilisation of estimates derived from them. Therefore design and application of bio-economic models for livestock genetic improvement could greatly benefit from participation of target groups and incorporation of sensitive systemic variables to improve repackaging of information that enhance sustainable adoption by actors in the livestock industry.

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Line-of-Sight-Polarized Wide-Band Mimo Measurements at 2-5 GHz

(Egerton University, 2012-10) Muhehe, D. J.; Muia, M. L.; Ogola, .W.

A short- range line of sight (LOS) multiple-input multiple-output (MIMO) channel transfer function was measured for a 4x4 system between 2.0 and 5.0 GHz. Measurements were made for a fixed antenna spacing of 2λ for all the four antenna polarizations in an indoor environment. Capacity and spatial correlation were investigated and the maximum mean capacity loss of 7.18% was realized when the orientation of the receiving and the transmitting antenna arrays were transformed from co-polar to cross-polar configuration. Furthermore, a validity test was conducted and the empirical distribution was found to be the same and within the theoretical values.

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Post-treatment Prevalence of Schistosomiasis and Geohelminthic Infections in Children and Adults Living along Lake Victoria, Kenya

(Egerton University, 2012-10) Njiri, O. A.; Odhiambo, R. A. O; Shivairo, R. S.; Karanja, D. M. S

Schistosomiasis and geohelminthic infections are major public health problems in developing countries and exert a heavy burden on morbidity when they occur singly or concurrently. Chemotherapeutic approach has been adopted in many endemic areas, using praziquantel and albendazole, based on World Health Organization (WHO) recommendations for control. The need for cost-effectiveness considerations in control strategies requires that greater emphasis be placed on further research to understand the factors that determine their occurrence and response to chemotherapy when they occur singly or concurrently. Towards this, a longitudinal survey in Kisumu and Siaya counties, Kenya, was conducted to assess the post-treatment prevalence of Schistosoma mansoni, Trichuris trichiura, Ascaris lumbricoidesand hookworms in school children (9–12 years) and adults over a 9-month period (September 2008 – May 2009). Adults were followed up monthly, while children were followed up every two months. Baseline prevalence of schistosomiasis was 52.0% + 2.5% in adults, and 38.5% + 1.8% in children while that of geohelminthiasis was 22.5% + 3.9% and 55.6% + 4.1% in adults and school children respectively. The difference in prevalence between the adults and children for both schistosomiasis and geohelmithes was not significant (P=0.9302), After 9 and 5 treatments in adults and children respectively, there was reduction in prevalence of schistosomiasis to 28.9% +2.3% and 24.0% + 3.1% in adults and children respectively, while in geohelminthiasis prevalence reduced to 4.3% + 1.5% in adults and 27.0% +2.5% in school children. These difference in prevalence among adults and children was not significant (P=0.8717). This study shows the differential occurrence of schistosomiasis and geohelmiths in children and adults. It also shows that frequent and consistent treatment decreases the prevalence of Post-treatment Prevalence of Helminth Infections along Lake Victoria 133 Egerton J. Sci. & Technol. Volume 12: 132-145ISSN No. 2073 - 8277 helminths in endemic areas and is effective both in adults and children. There’s however need for further studies to determine the most cost-effective strategies for mass drug administration, that will impact morbidity caused by helminths to sustainable levels in vulnerable groups.

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Determination of the Bending Strength and Hardness Values of Sisal Fiber Reinforced Polyester Composites

(Egerton University, 2012-10) Mutai, A. J; Ogola, W. O; Ondieki, C. M. M

The growing environmental consciousness and understanding of the need for sustainable development has generated interest in the use of natural fibers as reinforcements in polymer composites to replace synthetic fibers such as glass. The aim of this study was to determine the bending strength and hardness values of composite samples from sisal fibers and unsaturated polyester resin as the matrix. Chopped random sisal fibers were mixed with resin at various fiber weight percentages from 5, 10, 15, 20 to 40% sisal fiber. Hand lay- up and cold compression processes were used to produce test samples which were left to cure at 250C. The test samples were supported on knife edges and a roller edge central load applied on them for the three-point bend test. The hardness of the samples was tested on a Vickers micro-hardness testing machine. Results show that the 30%wgt fiber content had the highest value of 51.062 MPa for bending strength properties and 16.1 for hardness value while the unmodified sisal fibers recorded a bending strength of 40.382 MPa and a hardness value of 15 at the same fiber content. The modified sisal fiber has a better bonding between the fibers and matrix compared to unmodified sisal fiber therefore the composite samples could bear more load. It was also observed that surface modification of plant fibers result in superior bonding of the fibers and matrix. Sisal leaves produces fibers that could be used in composite manufacturing for use in roofing, partitioning and furniture applications.

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Influence of Maternal High Protein Intake on Daily Energy Expenditure and Lactation Performance in the Laboratory Mouse

(Egerton University, 2012-10) Kagya-Agyemang, J. K; Król, E.; Speakman, J. R.

Laboratory mouse (strain MF1) was used as a model to investigate the effects of high protein intake on daily energy expenditure and lactation performance. The specific dynamic action (SDA) for high protein (HP: 60% energy as protein) and high carbohydrate (HC: 70% energy as carbohydrate) diets was measured using open-flow respirometry at 9.4% and 6.1%, respectively. The same two diets were fed ad libitum to mice during lactation. Mice fed on HP and HC diets at 21 ºC reached an asymptote in their daily food intake at 12.29±0.2 g day-1 and 16.57±0.2 g day-1, respectively between days 12-17 of lactation. HP-fed mice had a significantly higher daily energy expenditure (DEE) measured by doubly labelled water (133.4±4.8 kJ day-1) and higher water turnover (41.1±6.2 g day-1) than HC-fed mice (DEE: 102.1 ±14.2 kJ day-1 and water turnover: 26.7±6.5 g day-1) but the energy they exported as milk was significantly lower (84.2±31.4 kJ day-1) than that of HC-fed mice (164.6±30.5 kJ day-1) and therefore resulted in poor growth rate of theiroffspring.The urea production of HP-fed mice from their daily protein intake of 7.1 g was estimated at 1994 mg which required 10.2 ml of water per day to be cleared. The mice increased their urine production by 14.4 ml probably to eliminate this urea.In conclusion, the MF1 mice fed HP diet at 21 ºC and the HC-fed mice reached an asymptote in their daily food intake at 12.29 g day-1 and 16.57 g day-1 respectively, between days 12-17 of lactation. HP diet had negative effects on lactation performance at 21 ºC when compared with the HC diet. The negative effects of the HP diet were due to the higher DEE which resulted from the heat production consequent of digestion and milk production by the HP-fed mice. Therefore, the higher DEE greatly reduced the energy available for milk production.This probably explains the reduction in growth of the pups/offspring from the HP-fed mothers because they did not get sufficient energy for growth.

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Determinants of Technical Efficiency in Rice Production in Gihanga (Burundi) Irrigation Scheme: A Stochastic Production Frontier Approach

(Egerton University, 2012-10) Ndayitwayeko, W-M.; Korir, M.

This paper estimated the technical efficiency of rice production under irrigation system in Gihanga, Burundi and attempted to unravel the determinants of technical inefficiency. A Cobb-Douglas stochastic frontier production function was used. The study showed that the average of technical efficiency was 73%. This meant that technical inefficiency of 27% constituted a challenge to overcome by the rice producers in Gihanga. According to Cobb-Douglas model, inorganic fertilizer and pesticide applications showed significant positive and negative effects on production function respectively. The inefficiency model revealed that technical efficiency increased significantly as result of experience but decreased with age of rice producers. There was room to expand rice production through appropriate farmers’ training and timely pesticide delivery. Besides, the extension service should be aware of the experienced farmers as a resource with potentials to train the less experienced ones and focus their attentions on the aged farmers.

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Transmission of a New Cowpea Aphid Borne Mosaic Virus Isolatein Passion Fruits

(Egerton University, 2020-01) Kiptui, Lucy; Kilalo, Dora; Toroitich, Faith

Passion fruitwoodiness is an important potyviral disease affecting passionfruits in the world. The causative agent for this disease in Kenya isCowpeaaphid borne mosaic virus. However, this disease manifestation in some fieldsat the present is different in regards to disease severity and symptomatologyfrom the commonly known variant.Thenewly identified isolate was namedCABMVvirus isolate1, while thecommonlyknownonewas named virusisolate 2.Currently, information onCABMVisolate 1 is scarce relative tothat ofCABMVisolate 2,which has been studied widely. This study wascarried out to determine whether virus isolate 1 is transmitted by seed andselect aphid species.The select aphid species are pest of crops grown near oralongside passion fruits in mostKenyan farms.For seed transmission test,mature seeds were isolated from fruits harvested from infected passion fruitsplants maintained in a greenhouse. Thereafter, the seeds were planted in anursery bed which was screened against aphids. The resultantseedlings hadno symptoms associated with virus isolate 1. Furthermore, using reversetranscription–polymerase chain reaction, seed transmission rate of 0% wasobserved, showing that this isolate 1 is not transmitted by seed.Aphidtransmission test was carried out in passion fruit plants using aphids fromfarmers’ fields in Njoro. Four aphid species which areAcyrthosiphon pisum,Aphis fabae, Schizaphis graminumandMyzus persicaewere selected for thestudy.The aphids were allowed30 minutes virus acquisition period on virusisolate 1 infected passion fruits plants. Thereafter, the aphids were left tofeed on healthy test plant for inoculation to take place. Symptomsdevelopment on healthy plants signified successful transmission by theaphids. Aphid transmission test results indicated thatMyzus persicae,Acyrthosiphon pisum,andAphis fabaesuccessfully transmitted the virus.

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Litter Processing of Exotic and Indigenous Leaves in Njoro River, Kenya

(Egerton University, 2021-02) Amuok, O.E; M’Merimba, .C.

The decomposition rate of riparian leaves can measure the potential of litter qualityas a food resource for aquatic organisms. This is valuable given the changing composition of riparian trees where exotic species are becoming more dominant. The core objective of this study was to estimate breakdown rates of riparian leaves and macroinvertebrates participation by examining four tree species common along the riparian areas of River Njoro, Kenya at Egerton University.The study assessed decay rates of the leaves of Grevillea robusta,Eucalyptus saligna, PittosporumviridiflorumandSyzygium cordatum in water. The classical decay coefficienct method was used after the leaves were immersed in water for 46 days. Syzygium cordatumand Eucalyptus salignarecorded the lowest decay rates (0.03). Decay rates for P. viridiflorumand G. robustawere 0.19 and 0.05 respectively. There was a statistically significant difference in the decay rates for each sampling day (p>0.05) for all tree species except S. cordatum. There was also a positive relationship between decay rate and macroinvertebrates for P. viridiflorum.Macroinvertebrate taxa favoredleaves of P. viridiflorumand G. robusta. Leaves of P. viridiflorum decayed faster, were softer and favoredby aquatic macroinvertebrates. ThusPittosporum viridiflorumleaves are of good quality and should notbe replaced by exotic species such as E. salignaand G. robustain riparian areas of streams. For aquatic and riparian management, planting of P. viridiflorum along river banks is encouraged to improve the qualityof food sources available for aquatic insects and the subsequent aquatic food web.

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Synthesis, Characterisation and Application of Capped Chromic Oxide Nanoparticle(CCONP) forthe Removalof Cd2+and Pb2+ion from Aqueous Solution

(Egerton University, 2019-10) Okuo, J. M; .O., Moses

This research was designed to ascertain the removal efficiency ofCd2+andPb2+ion from aqueous solution using capped chromic oxide nanoparticle(CCONP) synthesized by method of co-precipitation and thermaldegradation of chromic hydroxide (Cr(OH)3),stabilized and capped usingpolyvinyl alcohol (PVA).The physicochemical characterization of thesynthesizedCCONPwas evaluated usingx-ray diffractograms (XRD),scanning electron microscope (SEM)andFourier Transform infraredspectrophotometer (FTIR). The CCONPobtained was more ofcrystallinethanamorphouswithvery small particlesinapparently soft agglomerateswith asize of 7.7 nm. The amountofCd2+and Pb2+ions before and aftertreatment of the aqueous solution was evaluated usingatomic absorptionspectrometer (AAS).Adsorption experiments were conducted in batches andthe adsorption property of CCONP was studied using adsorption isothermmodels and optimized using response surface methodology (RSM) Analysis.The adsorption isotherm models revealed thattheadsorption process of Cd2+and Pb2+ions onto CCONP was a physical process, favorable andexothermic. The energy of affinity for Pb2+ions on CCONP was higher. Theadsorption process for Cd2+ions on CCONP was spontaneous and theadsorption capacity of CCONP for Pb2+ions was higher. However,optimisation analysis revealed that the cadmium ions were slightly moreadsorbed on CCONP and removed from the aqueous solution compared tolead ions. This observation was in agreement with the kFvalues obtainedfrom Freundlich isotherm in which the kFvalue for cadmium ions (59.52)was higher than that of lead (51.99).

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Clay-Rice Husk Ash based Geopolymers for Remediationof Pb (II) and Cd (II) from Wastewater

(Egerton University, 2019-10) Maingi, F. M.; Mbuvi, H. M.; Mwangi, H.; Ng’ang’a, M. M.

Industrialization and technological advancements have led tothegeneration ofnumerouspollutantssuch asheavy metals into the aquatic ecosystem. These toxiccompounds are extremely dangerous to humanhealthand the environment due totheir non-biodegradability, severe toxicity, ability toaccumulateand contaminateground and surface waters. Subsequently, pursuance of sustainable materials andtechnologies for better attainment of environmental sustainability is critical. Thisstudy reportsthesynthesis of geopolymers GP-1, GP-2 and GP-3fromdifferentclays. Geopolymers were hydrothermally synthesized using clay and rice huskswaste as an alumina and silica source respectively. The geopolymers werecharacterized using Fourier transform-infra red, energy dispersive spectrometry,X-ray diffraction and scanning electron microscope. Batch and gravitationalcolumn experiments using Pb (II) and Cd (II) ions were carried out. Increasedmetal ion uptake was recorded with raised Si/Al ratio of the adsorbents. The meanpercentage uptake of 90.23 ± 0.4 and 89.63 ± 0.18 of Pb (II) and Cd (II) wereachieved at pH of 4.0 and 5.0 respectively using GP-3.Langmuir, Freundlich andmodified Langmuir Freundlich isotherms were used in equilibrium studies.Datafor adsorption of Pb (II) and Cd (II) fitted best inthemodified LangmuirFreundlich model.The highest adsorption capacities of Pb (II) and Cd (II) were209.9 and 136.2 mg/g respectively, attained using GP-3.Based on the resultsobtained, geopolymers produced from common clay and rice husk wastedisplayed promising potentialsin theremoval of heavy metal ions from theaqueous phase. Considering the availability of raw materials forgeopolymerization and the high metal ions uptake capacities of geopolymers,they can also be used as adsorbents for removal of heavy metals in industrialwastewater.Keywords:Adsorption;Characterized;Geopolymers;Isotherm; Wastewater.

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Factors influencing Capacity of Beach Management Units in Implementing Fisheries Co-Management in Lake Turkana, Kenya

(Egerton University, 2019-08) Ogoma, M.O.; Kirui, B.K.; Obwoyere1, G.O.; Obura, E.O.; Otachi, E.O.

Lake Turkanafishery consists of 12 commerciallyexploited species andisthe second largest producer of freshwater fish in Kenya.Itsupportslivelihoods of approx.300,000 people locally.The lake is managed by beachmanagement units (BMU) through a co-management arrangementbetweenthegovernment and stakeholders.Despite this, itfacesmanagement relatedchallengesthathaveresultedinplummeting fish production due touncontrolled fishing effort,increased competition among fishermenanddeficientstatisticsto supportmanagement objectives.This studyassessed thecapacity of BMUs in implementing fisheries co-managementpolicybydescribingfunding sourcesand usage,trainingand skills development,equipmentownershipandlevelof understanding of BMU laws andregulations.A cross-sectionalstudy wasadoptedand purposive samplingused to collect datafrom 693 respondentsusing questionnaires.Chi squarewasused to test forsignificanceofassociationsbetween variablesat95%significant levelusingMINITAB statisticalsoftware.Results showed thatresource mobilization was statistically significant (x2=154.098, df=21,p<0.001)withdonors(45%) contributingmostfundscompared to nationalgovernment (21%), county government (19%) and well wishers (15%).Mainrevenue sources were membership registration (41%)and daily landing fees(25%).Revenue was used to purchase fishing gears (47%), supported welfareactivities(18%)whilesignificant portion (35%) was sharedbymembers.Members’ training was statistically significant (x2=79.510, df=14,p<0.001)but only 35%wereeffectively trained while 65%hadcontrary opinion.Memberswere trainedon fish handling (49%), BMU laws (28%)and micro-credit (23%) but keytraining gapsincludeddata collection, conflicts 30Ogoma et al., (2019)Egerton J. Sci. & Technol. Volume 17:29-49ISSN No. 2073-8277resolution and sea surveillance/patrols.BMUs ownedequipment;however,87%werepoorly servicedwhileotherswerenotavailable.BMUperformance could be improved mainly by providing financial support(27%), capacity building (19%) and securityto fishermen (17%).This studyidentifiedcritical capacityfactors influencingBMUoperations.Thefactorsshould be enhancedbyvarious stakeholders tosupportBMU performanceandpromotecollaborative management of fisheries resources in LakeTurkana.

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Variation of Human and Domestic Animal’s Activities with Discharge in a High Altitude Tropical Stream, the Njoro River, Kenya

(Egerton University, 2019-12) C. M. ,M’Erimba; Chepkorir,J. K.

From ancient times human settlements and cultures thrived along rivervalleys which provided water for domestic use as well as agriculture.aspopulation grew, human activities impacted river valleys as well as affectedwater quality. An investigation was carried out during low (January to March2012) and high (August to October 2012) discharge regimes in the NjoroRiver to establish whether the river’s discharge dictated the visit rate andactivities by people and animals at three sites. The study involved countingof people and animals during the day between 1000–1300hrs that visited theriver, and recording down the activities. The visit rate by people wasstatistically insignificant between low (30.75 ± 5.64 ind. hr-1) and high(20.58 ± 3.41 ind. hr-1) discharges respectively, (t =1.544, d.f = 70, p >0.05). A similar observation was made in mean visit rates by animals(t-value = 0.725, p > 0.05). However, significant differences in the rate ofpeople and animals (pooled data) were evident among the sites during lowand high discharge periods (one-way ANOVA, P < 0.001). More menfetched water at the most downstream site than women during both dischargeregimes, and the opposite was evident at the first site. It is concluded thatdischarge did not influence significantly the visit rates and other factors thatare site specific should be explored.Disturbances in the Njoro River are ofpress type and requires interventionfor themanagementof this river.

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