Theses & Desertations

EFFECTIVENESS OF SMALLHOLDER INDIGENOUS CHICKEN HATCHING SYSTEMS IN SIAYA COUNTY, KENYA

Mon, 01 Jan 2024 00:00:00 GMT

EFFECTIVENESS OF SMALLHOLDER INDIGENOUS CHICKEN HATCHING SYSTEMS IN SIAYA COUNTY, KENYA NAKHULO, EVANS NADECHO Poultry farming in Kenya plays a major role in complementing rural and peri-urban households’ food security and income. Farmers are increasingly shifting to rearing improved indigenous chickens (IC) because of their rapid growth rates and higher egg production. One of the strategies used by development agents in Kenya to enhance growth and meet market demand of IC is to supply day old chicks to producers. However, the demand for day old chicks outstrips supply because of low hatchability experienced in small holder hatcheries. Current study characterized the hatching systems of IC in Siaya County, evaluated and modified the performance of existing hatching systems and evaluated the performance of the adjusted schemes. Baseline survey was conducted on small holder farms and hatcheries to establish the characteristics of hatching systems in Siaya County. The study showed that breeding stocks were reared in enclosed and free-range systems, 55% of the farms attained the standard cock to hen ratio of 1:7 and eggs were stored using both conventional and non-conventional methods. The results further showed that the critical parameters of hatchability were outside the array with a mean hatchability percentage of 56%, Relative humidity (RH) and incubation temperature ranged from 54 to 64%, and from 37.2 to 39.5oC respectively. This study modified incubating system to; temperature range of 37.1 to 38.5oC, RH ranged from 56.5 to 62% and evaporative rate of 8.415*10-5m3/hr. The modified hatching environment yielded mean hatching of 95.3%. A model relating the amount of water to be added in the evaporative pan on a daily basis was developed and evaluated. The results showed that improvement of moisture management in incubators coupled with the physical and physiological management of hatching systems enhanced hatchability to 95.3%. This study provides specific technical modifications that can improve the design and operation of incubation systems, which can then be applied to the development of better hatcheries.

EVALUATION OF WATER QUALITY AND MODELLING POLLUTANTS DISPERSION USING QUAL2K MODEL: CASE STUDY OF RIVER SOSIANI IN WESTERN KENYA

Mon, 01 Jan 2024 00:00:00 GMT

EVALUATION OF WATER QUALITY AND MODELLING POLLUTANTS DISPERSION USING QUAL2K MODEL: CASE STUDY OF RIVER SOSIANI IN WESTERN KENYA OKORI, MAEMBA River Sosiani catchment area and River Sosiani provide drinking water for the city of Eldoret. During its course, River Sosiani receives untreated point-source pollutants as it winds through different agricultural, industrial and urban zone. Additionally, in wet season, the river receives non-point (diffuse) pollutants from the catchment containing soil, fertilizer and pesticide residues. The study assessed River Sosiani water quality and modelled pollutant dispersion using Qual2K model. Water samples were collected from six (6) sampling along River Sosiani for six months. American Public Health Association guidelines for water sampling and processing procedure were applied in sample analysis. In situ water quality parameters measured were Temperature, TDS, pH and DO while NO3-N, TP and BOD5, NO3-N were determined in the laboratory. The resultant data was analysed using both the descriptive and inferential statistics. The results showed statistically significant spatial variation of all water quality parameters between the means for DO (P=1.20E-19), BOD (P=8.32E-83), Temperature (P=6.00E-13), EC (P=5.32E14), TDS (P=3.18E-13), pH (P=1.15E-28), Nitrate-N (P=1.49E-33) and TP (P=1.06E-30). Seasonally, all parameters indicated significant temporal variation between the means for DO (P=5.66E-18), BOD (P=2.38E-03), Temperature (P=3.92E-11), EC (P=3.81E-10), TDS (P=1.31E-09), pH (P=1.35E-02), NO3-N (P=1.38E-13) and TP (P=6.72E-08). The Qual2K model was calibrated using dry season data and validated using wet season data. The model performance was evaluated using R2 , RSR and NSE. The Qual2K model performance values for R 2 , RSR and NSE ranged 0.82-0.95, 0.20-0.45, and 0.75-0.95 respectively. Conclusively, the study showed that River Sosiani water quality deterioration was caused by point and non-point pollutant sources.

CHARACTERIZATION OF WATER HYACINTH (EICHHORNIA CRASSIPES) COMPOSITE BRIQUETTE AS AN ALTERNATIVE DOMESTIC ENERGY SOURCE

Fri, 01 Jan 2016 00:00:00 GMT

CHARACTERIZATION OF WATER HYACINTH (EICHHORNIA CRASSIPES) COMPOSITE BRIQUETTE AS AN ALTERNATIVE DOMESTIC ENERGY SOURCE OKIA, DANIEL OTIENO Biomass is one of the most promising energy sources to mitigate greenhouse gas emission during production and utilization. However, majority of biomass are not suitable to be utilized as fuel without an appropriate process since they are bulky, uneven and have low energy density. These characteristics make them difficult in handling, storage, transport and utilization. One of the promising solutions to overcome these problems is the briquetting technology. The study was conducted to characterize water hyacinth composite briquette as an alternative domestic energy source. Water hyacinth was chopped using a shredder and left for two weeks in a heap to partially decompose. The material was thoroughly mixed manually with dried and crushed charcoal dust and cow dung in the ratios of water hyacinth: charcoal dust: cow dung of 100:0:0 (control), 80:10:10, 70:20:10, 70:10:20, 60:30:10, 60:20:20 and 60:10:30 (by weight). The resulting material was then mixed into soupy slurry in water. Simple prototype briquetting mold was fabricated to facilitate densification of these residues into hollow cylindrical briquette at a pressure of 1MPa. The experimental results revealed that the mixture that gave optimal combustion characteristics was 60:30:10 and the calorific values ranged from 16.215 to 21.585 MJ/kg. Water hyacinth alone (100:0:0) gave the best emission characteristics having 28.51 ppm carbon monoxide and 452.80 ppm carbon dioxide though ranking third with 13,623 μg/m3 in particulate matter. For quality control, water hyacinth composite briquette gave good indications on physical parameters that were measured. The results showed that resistance to water penetration range from 79.5% to 88%, durability index range from 57.9% to 99.6% with 60:30:10 and 60:20:20 ratios exhibiting poor index of 57.88% and 59.23 respectively probably due to high charcoal dust content which is known to have low bonding. The rest of mixtures gave 80% and above, with water hyacinth (100:0:0 ratio) showing the highest durability index of 99.63% probably because of partial decomposition which increases the binding effect of biomass. Equilibrium moisture content range from 8.5% to 15.2% at 29 oC and 58% relative humidity; water hyacinth alone was having the highest. This study therefore demonstrates that water hyacinth composite briquette have good physical and combustion characteristics and can therefore be utilized as alternative domestic energy source.

ASSESSMENT OF SOIL COMPACTION LEVELS BY FARM MACHINERY IN CULTIVATED SANDY LOAM SOILS

Thu, 01 Jan 2015 00:00:00 GMT

ASSESSMENT OF SOIL COMPACTION LEVELS BY FARM MACHINERY IN CULTIVATED SANDY LOAM SOILS TONUI, WESLEY KIPRONO The increasing soil degradation due to soil compaction may be linked to the increase in weight of agricultural machinery, in the more use of machinery even under unfavorable soil conditions and to poor crop rotation. The objective of the research was to assess the levels of soil compaction in cultivated fields. The research experiment was done in Elfam farm in Moiben Sub County, Uasin Gishu County, Kenya. The soils type was classified as Ferralsols with sandy loam texture. A four wheeled 70 kN tractor was used in the experiments. A multiple linear regression was used to describe the relationships of load, depth and number of passes for both bulk density and penetration resistance. The experiment was conducted at three levels of normal loads of 26 kN, 30 kN and 34 kN at four levels of number of passes 1,5,10 and 15 all with three replications. The field bulk density and penetration resistance were determined at varying levels of loading and number of passes using sand replacement method and Dynamic cone penetrometer respectively. The data was analyzed using statistical software for analysis of variance (ANOVA) at 95% confidence level and p < 0.05. From the results the highest bulk density at 34 kN and 15 passes was 1513 kg/m3 on the top soil. The lowest bulk density was 1116 kg/m3 on the subsoil layer below 45cm at 26 kN and one pass. The highest penetration resistance was found to be 52.50 J/cm at 30 kN and a depth below 45cm. The lowest penetration resistance obtained was 9.52 J/cm at 26 kN on the top soil layer. During the test period the moisture content average was 25%. The findings indicated that there was an increase in bulk density with the increase of loading and number of passes. The penetration resistance increased with loading, number of passes and depth. The iv increased loading and number of passes was particularly found to affect the soil layer above 45cm. From the study it was found that the effect of number of passes on bulk density increased with the increase in the number of passes. Also, loading and number of passes were found to have significant impact on penetration resistance. The coefficients of determination (R2) for bulk density and penetration resistance were found to be of 0.8822 and 0.8674, respectively. The relative compaction from the test results indicate that the soil was 95.5% compacted.

EFFECT OF IRRIGATION WITH TREATED WASTEWATER ON SOIL CHARACTERISTICS AND BEAN YIELD: A CASE STUDY OF UNIVERSITY OF ELDORET FARM

Wed, 01 Jan 2020 00:00:00 GMT

EFFECT OF IRRIGATION WITH TREATED WASTEWATER ON SOIL CHARACTERISTICS AND BEAN YIELD: A CASE STUDY OF UNIVERSITY OF ELDORET FARM MWANGI, VERONICA WANJIRU It is proposed that treated wastewater reuse with the correct regulations can be used to supplement the available amount of water for agricultural use. The research determines the effect of using this water on soil and crop yield. An experimental set up was done on 18 (1.5 m x 3 m) plots, where each plot received a different treatment. Experimental field treatments were set up at the University of Eldoret farm that is next to the waste water (WW) treatment plant. The farm is located in Uasin Gishu County, Kenya. The field experiments were carried out between June and October 2018. The research is directed at solving the problem of waste water reuse and disposal into rivers and lakes without strategic measures. Hence, the key objective of the study was to evaluate the effect of treated waste water irrigation on soil physical and chemical characteristics, and bean crop yield. The approach took a randomised complete block design (RCBD) where the treatments were replicated twice. For the treatments, treated waste water at 0 %, 25 %, 50 %, and 75 % NPK and fresh water at 0%, 25%, 50%, 75%, and 100 % NPK was applied to the plots. The fresh water at 100% NPK was considered as the control experiment. For all the plots, supplemental irrigation was carried out for the rainy season based on crop water requirement and growth stages for the crop. Treated waste water samples were collected from the tertiary pond and tested in the chemistry laboratory. Also, soil samples were collected for different plots after the planting period, and tested in the soil science laboratory. The bean yield was measured and recorded after the growth period. Results showed that plots irrigated with treated waste water and under 25% NPK yielded 1.55 Tonnes/ha and 50% NPK yielded 0.71 Tonnes/ha, which is more compared to fresh water irrigated treatments. Based on the statistical analysis, F critical is greater than F observed, that is 10.13 > 0.0164 and 9.28 > 0.0438, to accept the alternative hypothesis. Soils irrigated with waste water had better physical characteristics, more nutrients, and organic matter. Also, by comparing soil characteristics from waste water and fresh water plots, it is evident that soils irrigated with waste water showed prevalent and higher mineral and nutrient content. It is concluded that the simulated irrigation schedule for the two irrigation treatments can be used as a recommendation strategy for the farmers to adopt treated waste water recycling for irrigation. Also, the nutrients in the waste water can be used as an alternative to the inorganic fertilisers that are expensive.

MODELING OF RAINFALL-RUNOFF FOR A STORMWATER DRAIN IN ELDORET TOWN

Fri, 01 Jan 2021 00:00:00 GMT

MODELING OF RAINFALL-RUNOFF FOR A STORMWATER DRAIN IN ELDORET TOWN Metto, Abraham, R. Flooding in Eldoret town has been experienced during heavy downpours resulting in loss of property, life, and interruption of transportation systems. The overall objective of the research was to evaluate different scenarios of surface imperviousness and rainfall amounts on runoff generation and the influence of low impact developments (LIDs) on the generated runoff in Eldoret town. The specific objectives were: to determine the study sub-catchment characteristics (area, slope, percent impervious, rainfall, outflow, from the catchment); to calibrate and validate SWMM5 model for rainfall-runoff simulation in Eldoret; to evaluate different scenarios of rainfall and imperviousness proportions on runoff generation and to determine the influence of infiltration trenches and bio-retention cells as low impact developments (LIDs) on the study sub-catchment on stormwater runoff. On methodology, rainfall was measured using rain gauge while discharge was measured using the current meter. Digital Elevation Model of the study area was also obtained and processed. Five scenarios for analysis were formulated as follows: Maximum measured daily rainfall and increasing percentage imperviousness in tens from the actual 25% to 75%; Average measured daily rainfall and increasing percentage imperviousness in tens from the actual 25% to 75%; Minimum measured rainfall and increasing percentage imperviousness in tens from the actual 25% to 75%; The historical daily highest rainfall recorded between 2009 and 2019 with increasing percentage imperviousness in tens from the actual 25% to 75%; Historical average daily maximum rainfall recorded between 2009 and 2019 with increasing percentage imperviousness in tens from actual 25% to 75%. LIDs on stormwater runoff were also evaluated. The results showed that the catchment drained an area of approximately 696.5 hectares with a total of 23 sub catchments. The average slope was found to be 2.57% and the mean average imperviousness was 25.72%. The maximum 3-hr rainfall event observed during the study period was 32.4 mm which resulted in the maximum average discharge of 0.131m3 /s and resulted in overflow in the drain. The calibrated model had N-Imperv of 0.45, Dstore-Imperv of 2.5, and Dstore-Perv of 8. ISE values of 3.0 and 1.4 were observed for calibration and validation, respectively. NSE values of 0.97 and 0.99 were observed for calibration and validation, respectively. This meant that the model simulated well the rainfall-discharge relationship in the study area and can be used for engineering design purposes. Scenarios of percentage imperviousness and runoff indicated that impervious surfaces in urban areas are a determining factor in runoff generation and affects the average flow and total runoff positively. The results indicated a reduction of average runoff flow by 25% when infiltration trenches were used to an extent of 100% treatment of impervious area and a reduction in total runoff volume by 19.6%. Studied low impacts developments; bio-retention cells and infiltration trenches have an effect of reducing flow and total volume in the study area therefore can be used to control flooding. It was concluded that infiltration trenches are superior to bio-retention ponds in reducing flow and total runoff volume in the study area. Future study is required to calibrate the model for water quality analysis in the study area.

MODELING THE IMPACTS OF LAND USE CHANGES ON WATER QUANTITY AND QUALITY IN KIMWARER RIVER CATCHMENT

Mon, 01 Jan 2018 00:00:00 GMT

MODELING THE IMPACTS OF LAND USE CHANGES ON WATER QUANTITY AND QUALITY IN KIMWARER RIVER CATCHMENT I KIPLAGAT, DANIEL KIMUTA Kimwarer River basin has an area of 138.2 km2 . The basin has experienced ecosystem degradation due to extensive farming therefore impacting on water yield and nutrient loading in the basin. The study was undertaken to assess the impacts of land use changes on the quantity and quality of river flow by application of SWAT model. SWAT is a mathematical model that has potential of predicting the impact of land management practices on water and chemical yields at catchment scale. The specific objectives of the study were; i) To determine land use changes for the past 30 years; 1985 to 2015,ii) To calibrate and validate SWAT model for prediction of stream flow and nutrient loading in various land use scenarios and iii) To simulate stream flow and nutrient losses (nitrates and phosphates) in various land uses. Input data to SWAT model were assembled from relevant sources. Current and historical flow data were collected for the purpose of model calibration and validation. The model was then used to simulate quantity and quality of stream flow for different land use and land cover scenarios by interchangeably varying forest cover and agriculture. Results showed that from the year 1986 to 2010 for which images were obtained, there were; increase in agricultural land from 62.68% in 1986 to 84.52% in 2010, decrease in forest cover from 17.33% in 1986 to 9.66 % in 2010 and the decrease of wetland from 19.99% in 1986 to 5.84% in 2010. The model was successfully calibrated and validated for stream flow. The model was capable of predicting flow during calibration with R2 and NSE values of 0.79 and 0.31 respectively. During validation, the model predicted flow with R 2 and NSE values of 0.70, 0.50 respectively. For scenario analysis to determine the effect of land use change on stream flow, it was observed that surface runoff decreased with increase in forest cover while base flow increased with increase in forest cover. Introduction of terraces as management operation option in agricultural land showed a reduction in runoff by 46%. The model was capable of predicting nitrate and phosphate losses with R2 of 0.72 and 0.79 respectively. The observed mean monthly basin loading levels were 0.10 kg/ha and 0.092 kg/ha for nitrates and phosphates respectively. Nutrient losses decreased with increase in forest cover. From the research it is evident that the current trend of land use change affects the quality and quantity of water from the catchment. The trend requires control for sustainability.