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Item Climate Variability and Malaria Transmission Trends in Different Altitudes of Lower Lake Victoria Basin, Kenya.(Kenyatta University, 2023-11) Odhiambo, Samwel Olela; George L. Makokha; Kennedy ObieroConsequences of global climate variability and change are some of the biggest environmental challenges the world is facing. Impacts include increased frequency of extreme weather events. The impacts vary, Africa being the most vulnerable due to her high dependence on natural resources. One of the issues most associated with the challenges is malaria prevalence. Half of the worldâs population, (3.4 billion people in 92 countries), is at risk, 1.1 billion at high risk. Malaria burden is greatest in the developing countries of the tropics such as Africa which has 91% of the related deaths, 60% being children under five years. Climate extremes have increased in East Africa, which is predicted to add 75.9 million people to the risk bracket. In Kenya, malaria is blamed on high rainfall, temperature and relative humidity. This study evaluated climate variability and malaria transmission trends in different altitudes of Lower Lake Victoria Basin (LLVB), Kenya where malaria prevalence rate was 27% despite varying between 4% - 8% in other parts of the country. Descriptive and correlational designs with quantitative methods were used to analyze spatiotemporal variability of selected climate elements and malaria transmission trends. Target population was flooded malaria morbidity cases recorded at Sub â County Hospitals. Meteorological data was obtained per sampled county and sub - county i.e. Migori - SONY Central Meteorological Station, Kisumu - Kisumu Airport Meteorological Station and Kakamega -MSC Meteorological Station. Data for the selected climate parameters were collected for twenty years except Relative Humidity from Kisumu Airport which was only available for 12 years (2009-2020). Health data was obtained from the Kenya Health Information System (KHIS) for ten years (2011 to 2020) through sampled Sub-County Level 4 Hospitals. ANOVA was used to analyze variability among climate and malaria transmission variables, Pearsonâs Correlation Coefficient tested relationships while Descriptive Time Series and âARIMA regression modelsâ were respectively used to give trends and to predict future climate and malaria scenarios. Results revealed that Malaria transmission and climatic variables significantly varied in space and time. Mean annual malaria transmission in Kisumu was 3902.87, Kakamega 3385.53 and Migori 2130.33. Mean annual temperature was 23.770C in Kisumu, 22.610C in Kakamega and 22.520C in Migori. The two had insignificant monthly and annual correlations. However, climate elements insignificantly defined transmission differently at different altitudes. In a further analysis, stepwise linear regression dropped all climatic variables and left only altitude as the significant determinant of malaria transmission variability in the LLVB. This made the study use altitude and transmission levels to zone LLVB as follows: 1001m to 1200m â high transmission; 1201 to 1400 - medium transmission; 1401 to 1600 â low transmission. The study predicted that malaria transmission would increase in high and medium transmission zones while decreasing in low transmission zones. This meant that malaria prevalence would still vary depending on altitude. The revelations were used to inform experts in policy decision making on reduction of malaria transmission. This was to enhance malaria eradication processes in the LLVB, Kenya, and hence promote the realization of Kenyaâs vision 2030.Item Productivity and Cost-Benefit Assessment of Agroforestry Systems Based on Pentaclethra Macrophylla and Acacia Auriculiformis in Lobilo Catchment, Democratic Republic of Congo.(Kenyatta University, 2023-11) Assani, Neville Mapenzi; Raphael Kweyu; Nsharwasi LĂ©on. NabahunguAgroforestry systems (AFS) have a good reputation for boosting soil fertility and crop production and providing ecological services, all of which are necessary to ensure continued food security for a rising population without severely worsening environmental conditions. Pentaclethra macrophylla and Acacia auriculiformis are among important tree species used in AFS in Congo basin. Positive or negative effects of these trees on crop production, carbon (C) storage and financial profit in agroforestry system have been poorly or not been addressed in earlier studies. Hence, this research compares the impact of Pentaclethra macrophylla (native species) and Acacia auriculiformis (exotic species) based AFS on soil macro-nutrients, food crops (cassava, maize, and peanut crops) yield, the above ground and soil organic carbon as well as the financial profit during two cultural years. The study sought to investigate the effect of these trees and their planting densities on AFS productivity and financial income. The plot experimentation was a multifactor design implemented through Lobilo catchment in Democratic Republic of Congo (DRC). This experiment had 2 tree-species, 4 tree- planting density or tree-spacings (2500, 625 and 278 treesĂha-1 as well as monocropping), and 3 food crops. Noted that each pot has been replicated 3 times. Thus, this multifactorial trial had a total of 72 plots (2 trees species Ă 3 food crops Ă 4 planting densities Ă 3 repetitions) and each plot size was 400 m2, 3.2 ha at total. It was implemented between March 2020 and March 2022 corresponding to four cropping seasons. All analyses and visualization were performed using R 4.2.1 version (R Core Team 2022). Mixed effect regression analysis was carried out to assess the link between studied parameters and treatments and analysis of variance (ANOVA) was used to estimate marginal means computed for the significant sources of variation and treatments comparisons adjusted to identity homogeneous groups. The results revealed that the two agroforestry-species did not differ significantly with regard to their effects on soil nutrients, however, the total N, P and the pH increased over the growing of cropping season. Concerning the food crops yield variation, the yields of cassava and maize were greater under P. macrophylla than under A.auriculiformis. Furthermore, the tree density of 2500 treesĂha-1 of the both tree species negatively affect food crops yield. Concerning the Carbon storage, A.auriculiformis stocks more AGC than P. macrophylla. Likewise, concerning the financial profit of these AFS, the high planting density (2500 trees per hectare) decreases the financial profit because the most cost for the implementation of this AFS is spend for seedlings production. Furthermore, the both tree legume species associated with cassava shows positive net revenue but when associated with maize and peanut they show negative net revenue. This study has increased our knowledge on the association of P.macrophylla (native trees) and A.auriculiformis (exotic trees) with food crops by suggesting that the both tree species can be used in agroforestry systems at 625 treesĂha-1 associated with Cassava for financial profit and associated with peanut for biomass and above ground carbon benefit. Moreover P.macrophylla is more efficient in food crops production while A.auriculiformis is more efficient in above ground carbon storage. Therefore, there is need to enact laws that extend the association of native trees species with food crop in agroforestry system for balancing the needs of biodiversity preservation, food security, and ecosystem services in Democratic Republic of Congo. This research encourages scaling out this AFS system using other native tree species in Congo basin in order to meet food security without significantly degrade the environment.Item Examining the Poverty-Land Degradation Nexus in Kitui County, Kenya through a Political Ecology Lens(Kenyatta University, 2022) Mutiso, Mary N.; Calvine Kayi; Mary KinyanjuiThe twin problems of poverty and landdegradation have persistently plagued Kenya in general and Kitui county in particular. Colonial and post-independence governments devised state policies and interventions to address these problems without much success. The overall aim of this study was to examine the nexus between poverty and land degradation. The specific objectives of the study were first, to examine the role played by colonial economic policies in the development of poverty and land degradationin Kitui, second, to analyze the relationship between the assets owned by households and their poverty levels, third, to assess the effect of the land management practices adopted by households in Kitui on the Land management outcomes and fourth, to evaluate the relationship between the assets owned by households in Kitui and their choice of land management practices. The study employed political ecology and the the investment poverty frameworks respectivelyto analyse,first, the the role of colonial policies in the development of poverty and land degradation and, second, the link between poverty, land management practices, and land management outcomes. The study used a mixed-methods analytical study design. Cross sectional data was collected using aquestionnaire while historical data was collected from archival and secondary sources. Three hundred and eighty-three households were sampled using the population proportional to size sampling method. This study used assets that a household had as measures of poverty and farmersâ perceptions of environmental problems as measures of land management outcomesIt analysed the data as follows; First, a historical analysis of the dynamics of poverty and land degradation in Kitui was undertaken to examine the influence of colonial economic policies on the development of poverty and land degradation. Second, the assets influencing household consumption (poverty) were identified through a regression between household consumption and household assets. Third, the study identified the land management practices practices influencing land management outcomes using Chi-square statistics. Finally, a regression of the determinants of poverty with the determinants of land management practices practices yielded the determinants of land management practices practices. This study identified four determinants of poverty levels namely: education, the number of active household members, land size and access to extension services. It associated crop failure, soil erosion, and vegetation cover depletion with land management practices. Finally, three assets, namely education, the number of household members between twenty and sixty (out of how many) and advice from extension officers influenced land management practices households in Kitui adopted. Since the factors that influenced poverty also influencedland management outcomes, the study concluded that poverty and land degradation are outcomes of the same causes and processes and therefore not necessarily mutually reinforcing phenomena. It therefore refuted the Vicious Circle hypothesis. Policy interventions to eradicate poverty and land degradation should therefore be on education, labour and extension services.Item Effects of Land Use/Land Cover Change and Rainfall Variability on Hydrological Characteristics of River Ruiru Watershed, Kiambu County, Kenya(Kenyatta University, 2021) Waithaka, Ann; Shadrack K. Murimi; Kennedy ObieroWatersheds and their water resources are highly vulnerable to land use/land cover changes and seasonal rainfall variability as they directly influence basin hydrological characteristics in terms of water quantity and quality. This study assessed the effects of land use/land cover change and rainfall variability on hydrological characteristics of River Ruiru watershed in Kiambu County. The study integrated the use of remote sensing, Geographic Information System (GIS), water quality sampling, hydrological modelling and statistical methods to collect and analyse the collected data. Results of land use/land cover change analysis indicated that built-up areas, annual crops and perennial crops (tea and coffee) increased by 3.068%, 35.848% and 11.493% respectively between 1976 and 2017. However, it was observed that perennial crops increased gradually between 1976 and 1995 but declined by 1.94% between 1995 and 2017. Grassland, shrubland and forestland declined by 7.48%, 13.25% and 29.79% respectively between 1976 and 2017. Consequently, Soil and Water Assessment Tool (SWAT) model simulation results indicated that the land use/land cover changes that occurred in River Ruiru watershed between 1984 and 2017 had effects on the quantity of river discharge and water quality for drinking purposes. Surface runoff (SURQ), lateral flow (LATQ) and groundwater contribution to discharge (GWQ) increased from 30.25mm/yr, 8.48mm/yr and 9.95mm/yr to 181.25mm/yr, 11.44mm/yr and 10.66mm/yr respectively. Moreover, the nitrates in surface runoff (NO3SURQ), nitrates in lateral runoff (NO3LATQ), Organic Nitrogen (N.ORG) and Organic Phosphorus (P.ORG) increased from 0.05kgN/ha/yr, 0.06kgN/ha/yr, 5.77kgN/ha/yr and 0.87kgP/ha/yr to 1.47kgN/ha/yr, 0.19kgN/ha/yr, 70.60kgN/ha/yr and 8.86kgP/ha/yr respectively. In additions, findings from the study indicated that temporal rainfall variability had effects on the quantity of river discharge and water quality of River Ruiru. Based on regression analysis, the correlation between the observed and predicted value of dependent variable indicated an association of R=0.972 between temporal rainfall variability and quantity of river discharge hence showing a strong positive linear relationship. Similarly, Pearsonâs correlation analysis results showed that temporal rainfall variability was strongly and positively correlated to NO3, N.ORG and P.ORG with R=.695, p<.001; R=.781, p<.001 and R=-.780, p<.001. Furthermore, results from a paired sample t-test indicated that pH, turbidity, Dissolved Oxygen (DO), electrical conductivity and Total Dissolved Solids (TDS) had higher mean during wet season (M=8.40, M=79.00, M=51.20, M=87.00 and M=54.20) than in dry season (M=6.80, M=11.60, M=43.40, M=73.00, and M=45.40). The difference for these water quality parameters between dry and wet seasons was significant (P=0.003, P=0.034, P=0.005, P=0.013 and P=0.014). Moreover, findings from the study indicated that DO, TDS, electrical conductivity, total phosphorus and total nitrogen values were within World Health Organization (WHO) and National Environment Management Authority (NEMA) recommended values. However, the results for the total coliforms and E. coli indicated that River Ruiru was severely polluted with faecal organisms. In conclusion, land use and land cover changes and temporal rainfall variability have affected the quantity of river discharge and water quality in River Ruiru watershed. As such, remedial actions to address the hydrological effects of land use/land cover change and temporal rainfall variability both by national and county governments are required.Item Quantification of Greenhouse Gas Fluxes and Derivation of Maize Cropping Calendar in Croplands under Rainfall Variability in Kenya(Kenyatta University, 2019-04) Macharia, Joseph MainaIncrease in global atmospheric greenhouse gases (GHG) has led to an increase in the radiative forcing resulting in climate variability. The objective of this study was to identify the best management practice which ensures high maize productivity while emitting as little GHG fluxes as possible under the influence of rainfall variability. The study was carried out in three major parts of Kenya, that is, Kenya as a whole, the agricultural potential zones and central highlands of Kenya. The accuracy of the satellite precipitation products was determined based on data obtained between 1983 and 2013 from Climate Hazards Group InfraRed Precipitation with Station (CHIRPS), Global Precipitation Climatology Center (GPCC), National Aeronautics and Space Administration-Prediction Of Worldwide Energy Resource (NASA-POWER) and Tropical Rainfall Measuring Mission - Multi-satellite Precipitation Analysis 3B42 version 7 (TRMM). The satellite data were compared with observed data from Kenya meteorological department. The soil GHG fluxes were quantified from maize production experiment in Mbeere South sub-county for one year using static GHG chambers. The DeNitrification-DeComposition (DNDC) model was parameterised using experimental data and used to simulate GHG fluxes. The length of the cropping season, onset and cessation date in the agricultural zones of Kenya were determined using daily satellite data from NASA-POWER between 1983-2017 using RAIN software. Results show that all satellite products either overestimated or underestimated rainfall amounts on a pixel to pixel comparison. The TRMM product best estimated rainfall in the tropical cool humid (r2=0.64), tropical warm humid (r2=0.58) and tropical cool sub-humid (r2=0.39), GPCC product in the tropical warm semiarid (r2=0.46) and tropical warm sub-humid (r2=0.21), NASA- POWER product in tropical cool arid (r2=0.97) and tropical cool semiarid (r2=0.53) while CHIRPS product best estimated rainfall in the tropical warm arid (r2=0.33). Cumulative annual GHG fluxes ranged from -0.05 to -0.65 kg CH4-C ha-1 yr-1, 1.31 to 3.39 Mg CO2-C ha-1 yr-1 and 0.12 to 1.15 kg N2O-N ha-1 yr-1 for the four different treatments respectively. Animal manure produced the highest amounts of CO2 emissions (P<0.001) and N2O fluxes (P<0.001) and the lowest yield-scaled emission (0.5 g N2OâN kg-1 N). Animal manure + inorganic fertilisers produced the highest amounts of CH4 fluxes (P<0.001) and the highest YSE (2.2 g N2OâN kg-1 N). The DNDC simulated GHGs followed seasonality with peaks recorded immediately after the onset of rains which coincided with fertilisation. The DNDC simulated CO2 was slightly higher than observed while the N2O were slightly lower than observed though not significantly different at P=0.05. Results on cropping calendar demonstrate two key regions in Kenya, one with two seasons namely; the Long rains (LR) and Short rains (SR) and the other one with one season in a year. The LR onset is experienced in March and cessation in July; the SR onset in September and cessation in November while the one season onset in March and cessation in October. The LR and SR length of growing season ranges between 23-90 days while that of one season ranges between 192-259 days of sufficient rainfall. These results demonstrate the promising potential of the satellite data in complementing the unreliable data in Kenya. Animal manure has the ability to increase maize yields while simultaneously reducing yield-scaled GHG emissions. The DNDC model provides an accurate and cheaper alternatives for quantifying GHG for national GHG inventories and reporting to the UNFCCC. The results also derive a cropping calendar crucial for the planning of agricultural farming activities which will ultimately reduce losses and improve rainfed agricultural production.Item Spatial Analysis of Constraints and Opportunities in Banana Value Chain in Meru County, Kenya(Kenyatta University, 2018-11) Mbuthia, Susan WanjiruThe changes such as increases in urban dwellers and demand for high quality and safe products being witnessed in agrifood systems around the world present opportunities for farmers to orient production to meet the emerging needs. To this end, governments in Sub- Saharan Africa have been reconstituting new trading policies. In Kenya, banana farming is a prospective activity through which small-scale farmers could exploit the emerging opportunities. This study examines the banana value chain in Meru County in order to determine the constraints and opportunities therein and the farmersâ responses. Although agricultural value chain studies are strongly recommended as possible intervention strategies of increasing the farmersâ competitive position in their activities, past studies on banana farming in Kenya mainly focused either on production or marketing. This study focused on the following objectives; profiling the demographic-socio-economic characteristics of farmers and traders, determining the constraints and opportunities in banana value chain, and evaluating the spatio-temporal distribution of periodic banana markets. A survey design and mixed method approach were used in data collection. Research instruments included: (i) Questionnaires administered to 384 farmers and 384 traders who were purposively selected. (ii) Interview guide used for 8 key informants. (iii) Focus group discussion guide used for 2 groups. Data processing and analysis was done using excel and SPSS. Quantitative data was analysed using analysis of variance, t test, Pearson correlation coefficient and nearest neighbour index. Qualitative data analysis was guided by SWOT and Scoring cards. Results showed that: women dominated production (52.6%) and marketing (57.6 %); a significant (p < .000) difference existed between earnings by men (Ksh 16,770) and women (Ksh 14,249) farmers; farms were small (1.9 acres) and significantly (p = .032) different in size across the sub counties; and 177stools were harvested monthly but significantly (p < .001) varied across locations. Wholesalers dominated banana trading. Pests and diseases (23.2 %), and high marketing costs (24.2 %) were the leading constraints. Opportunities included; short distances (3.3 kilometres) between farms and markets which significantly (p < .000) varied with locations, and unmet demand for bananas and high prospects for value additions. Markets with a closer time dimension did not have a wide spatial distance and vice versa (r = -0.530, p = .076); and the banana markets were not uniformly distributed (Rn = 0.31). The study concluded that: (i) some demographic-socio-economic characteristics of farmers and traders influenced their activities in the chain. (ii) The chain is characterized by several interdependent constraints (iii) Banana value chain has enormous potential to benefit farmers (iv) Markets do not meet the needs of the farmers equally. It is therefore recommended that: (i) community training on production and entrepreneurship targeting women to be conducted. (ii) Meru County government to partner with private firms in helping farmers address constraints and exploit existing opportunities. (iii) Banana traders to curve out a niche market in order to promote banana value addition, and (iv) the County government to either reorganise market in synchronised way or establish new ones in areas not optimally served.Item Assessment of Past and Future Climate Change as Projected by Regional Climate Models and Likely Impacts Over Kenya(Kenyatta University, 2019-05) Sagero, Philip ObaigwaClimate change and variability is one of the global challenges that is affecting development worldwide. In the recent time, Regional Climate Models have been relied upon to give high-resolution climate projection at a local scale for impact assessment and development of adaptation strategies. These models are used to downscale the Global Climate Models which are used in the preparation of Intergovernmental Panel on Climate Change assessment reports. To provide local scale information for impacts assessment, vulnerability analysis and adaptation strategies, projection of future climate change must be of high resolution. This study was able to assess the past and future projections in climate as projected by the Coordinated Regional Climate Downscaling Experiment, Regional Climate Models, with a 50 km spatial resolution over Kenya. To achieve the objective of the study, analysis of the past rainfall and temperature pattern and trends over Kenya was done using observed station data and gridded datasets. The skill of the models to simulate the observed pattern and variability was determined using gridded datasets (Global Precipitation Climatology Center and Climate Research Unit) for both rainfall and temperature (minimum and maximum). Interannual rainfall variability over Kenya is controlled by large-scale systems, therefore the ability of the models to capture these teleconnections was analyzed by use of the composite method. After testing the skills and abilities of the regional models, then an assessment of the future changes on rainfall and temperature as projected by the models under Representative Concentration Pathways (RCP) 4.5 and 8.5 emission scenarios was done. Also, the future change in climate extreme was also analyzed by use of climate extreme indices. Finally, an analysis of the likely impacts of the projected changes on different sectors of the economy over Kenya was also done. The results show that rainfall and temperature over Kenya is variable from one place to another. The regional models were able to simulate rainfall and temperature well over Kenya. They also capture well the spatiotemporal patterns of rainfall and temperature over Kenya. An increase in temperature of about 5 oC is projected by the end 21st Century under RCP4.5 and RCP8.5 scenario. The minimum temperature is expected to increase more than maximum temperature thus increase/decrease in warmer/colder nights. All the models 0show a better agreement on temperature projections. 70% of the models projected a decrease in March April May rainfall and an increase in October November December rainfall under RCP8.5. And a decrease in both season under RCP4.5. There is no significant change in the precipitation extreme indices except for Consecutive Dry Days and Consecutive Wet Days which are projected to increase and decrease respectively. Nevertheless, there is a clear decrease in annual precipitation totals. The models project high rainfall variability with a small shift of increasing trend. These projected changes will negatively impact agriculture, health, water and energy sectors and there is need for development of adaptation strategies at local level. The findings of the study can be used by government to develop adaptation strategies that will increase resilient of local communities. The models were not coherent in their rainfall projection, therefore further studies should be carried out on based on an ensembled model and the physics of the models should also be looked at, to find out whether the mesoscale system that affects rainfall over Kenya are well included in the models.Item Demographic and spatial-temporal dimensions of marital instability and its effects on the family livelihoods in Machakos County, Kenya.(Kenyatta University, 2016-02) Masua, Musau JacksonThis study aimed at establishing demographic and spatial-temporal dimensions of marital instability among women in the rural areas and its effects on their family livelihoods.The study adapted a case study design in which through simple random sampling, one Division was randomly selected in each of the three sampled Districts in Machakos County. Purposive and snowball sampling methods were used to sample the respondents.In total, the sample constituted of 300 women aged between 15-49 years who were separated, divorced or deserted by their husbands.Primary data were collected from the field using questionnaires, Focus Group Discussions (FGDâs) and Key Informants.The information was supplemented by secondary data from library and Internet.The collected data were edited, coded and then subjected to descriptive analysis, and inferential statistical analysis using Chi-square test (Ï2), correlation analysis, and logistic regression among other statistical tools. Results indicate that, out of the sampled women,78% were separated,11.3% deserted, and 9.4% divorced while 1.3% had filed for divorce.The separation rate was found to decrease with increase in age while desertion and divorce rates increased with increase in age. Results indicate that, womens (p=0.038) and husbands (p=0.0001) age at marriage influenced marital instability.The median age at marriage of this group of women is 19 years; their mean duration of marriage and age at separation is 7.5 years and 26.6 years, respectively.The odds of separating increased by 51% and 80% for women who had 2-3 or more than 3 children, respectively.The odds reduced by 71% and 67% for those who courted for less than 1 year and 1-2 years respectively.Irresponsibility (74%) and infidelity (51.3%) were found to be the leading factors influencing marital instability.Violence (42.3%), alcoholism (38.7%), in law problems (24%),unemployment (11%),age difference (10%), and polygamy (10%) were the other cited reasons.Family background factors such as father education (p=0.040) and occupation (p=0.020), parentsâ marital status (p=0.005) and approval of marriage by the parents (p=0.018) highly influenced the rate of marital instability.The rate was also high among women with low level of education while cohabitation was found to be insignificant.Place of resident before and after marriage showed significant (p=0.016) association with marital instability. Results on domestic assaults in particular sexual abuse in marriage appear to be more of a reaction from other problems in marriage just as it is physical assaults and alcoholism.There was a strong association between physical assaults and forced sex (0.788).Results and data analysis further indicate that ,most of the separated mothers are faced with challenges of achieving and maintaining their livelihoods due to financial hardships (98%).About 89.3% lack shared parenting with their former husbands; 68.3% lack economic support from their relatives, government and NGOâs.This increases their vulnerability to poverty.Majority rely on casual jobs (44.7%) or are self-employed (42.7%).They live in rented houses (61%), or with relatives (29.7%).Most of them (93%) are left with young children aged below 12 years at the time of separation. Poverty affects their children as depicted by the high rates of school dropouts in primary (21%) and secondary (9.7%) and also increased use of child labour in the region.From the research findings, it was recommended that, there is need for the Kenyan Government, the County Governments and NGOâs through the relevant department offices to sensitize the public about the causes and outcomes of family conflicts and to address the root cause of child labour, create livelihood opportunities and poverty reduction schemes for separated/divorced parents in the rural areas.These recommentations will improve livelihoods and reduce poverty especially among the affected female headed households in the rural areas.Item Management practices of irrigation water and their effects on water allocation among farmers in Kiladeda sub-catchment, Tanzania(Kenyatta University, 2016-02) Mwadini, J. KhatibIrrigated agriculture plays a major role in the livelihoods of Kiladeda sub catchment, Pangani Basin, Tanzania. However, the sub catchment is experiencing a problem of inequitable distribution of irrigation water among farmers. The challenge is escalated by rapid population growth, economic growth, other water users and irrigation management practices. This situation has increased conflicts and insufficiency in irrigation particularly in downstream of the river. This study aimed at assessing the management practices of irrigation water and their effects on water allocation among farmers in Kiladeda sub-catchment, Tanzania. Specifically, the study analysed socio-economic factors influencing irrigation water demand; examined irrigation management practices adopted by farmers and their effects on irrigation water demand; investigated irrigation water demand and allocation among farmers and evaluated strategies used to mitigate irrigation water demand and allocation disparities among farmers. The study employed both primary and secondary data. The primary data were collected by interviewing 150 farmers, key informant interviews and measurement of river discharge while secondary data were collected from relevant institutions in Moshi, Tanzania. Numerical tools for data analysis comprised of descriptive statistics, independent sample t-test, stepwise regression, content analysis and WEAP model. The stepwise regression results showed that farm location and farm size (13.5%); income and farm location (19.8%) and; farm ownership, education level and income (39.6%) were the predictors of irrigation water demand for the whole river, upstream and downstream zones respectively. On the other hand, all nine factors in the middle stream zone were eliminated by the model. The study also revealed that furrow irrigation (86.7%) and plastic buckets (13.3%) were the main irrigation techniques employed by farmers in the sub catchment. However, there was no significant difference between irrigation techniques adopted and irrigation water demand in the sub catchment (p >0.05). On the contrary, there was a significant difference between irrigation water demand and irrigation techniques in upstream zone of the sub catchment (p <0.05). The results of WEAP model revealed that the sub catchment has water shortage of about 53% of the total irrigation water required. The current annual irrigation water demand is 18.44Mm3 and unmet demand is 9.8Mm3. Both water demand and unmet demand are expected to increase twice in 2020. The high water demand for irrigation could be the main cause of excessive water abstraction in the upstream and downstream zones of the sub catchment. Moreover, the study identified water pricing, formation of water users associations, public education, reduction of farm sizes, changing crop types, water rights as well as laws and regulations on water allocation, as the main strategies implemented to reduce water demand and allocation conflicts. The study found that despite of water shortage in the sub catchment, water was not used efficiently for irrigation activities. Therefore, the study recommends partnering approach to improve irrigation water management; reviewing of laws, regulations and water rights to conform to the current irrigated areas and irrigation water requirements. More so, extension services to farmers should be improved. This will serve as a source of information and training forum for farmers on irrigation water management practices and therefore enhance efficient use of water for irrigation.Item Effects of geomorphic processes and land use activities on slope stability in Mount Elgon region, Eastern Uganda(2014) Gumisiriza, Turyabanawe LoyThis study assessed the effects of geomorphic processes and land use activities on slope stability in Mount Elgon region, in Eastern Uganda. The main objective was to assess the stability of slopes in Mount Elgon so as to map the instability prone areas. To achieve this, the study investigated geomorphic processes and land use practices taking place on slopes and the role of geomorphic processes and land use activities in rendering such slopes unstable. In addition, zonation and mapping of slope instability risk areas, assessment of peoplesâ perception and attitude towards slope failure as well as response to evacuation programmes put in place by government were assessed. Data was collected through field surveys as well as interpretation and analysis of aerial photographs and Landsat imagery. Interaction with land users, planners and local authorities was conducted through questionnaire administration, conducting interviews, and focus group discussions. Data analysis involved both qualitative and quantitative techniques. Qualitative analysis involved computation of non-arithmetic relations. Descriptive statistics and percentages were used while correlation coefficients and chi- square tests were computed to determine the forms and strengths of underlying relationships. The study established that Mount Elgon is a naturally unstable environment with regard to slope stability. Geomorphic processes especially weathering and undercutting of slopes by rivers was found to contribute directly and indirectly to slope instability experienced in the region. Land use activities such as cultivation, construction and associated clearance of forests have aided natural processes to destabilize the already unstable slopes triggering slope failure. The study classified the slopes in the area into slope instability hazard areas according to when slope failure was last experienced and slope instability risk areas based on slide potential as seen from slope gradient. Even though majority (70%) of the respondents expressed awareness of the unstable and landslide prone environment they are living in, they have over time developed an attitude that has led them to ignore landslides even though they disrupt their life when they occur. The coping mechanisms adopted as well as the peopleâs response to evacuation programmes following slope failure were established to be popularly in favour of staying (84.5%) rather than evacuation (15.5%) from the risk areas. The study concludes that although natural prerequisites for slope failure are ample and of overruling importance in Mount Elgon, human activities need to be regulated or better still prohibited in order to address the situation. The study provides a landslide inventory and slope stability database upon which policies regarding use of land in slope instability hazard areas can be formulated. The intervention strategies recommended by this study could also offer practical short term and long term remedies where ever a similar problem is experienced. Following such a study, studies on landslide vulnerability assessment, resilience and coping mechanisms related to landslides need to be conducted in the area and other areas that face similar hazards.Item Sexual Concurrency among Married Couples in the Fishing Communities along Lake Victoria in Kisumu County, Kenya(2014-08-20) Kwena, Zachary A.; Shisanya, C.A.; Mwanzo, I. J.; Bukusi, E. A.HIV remains a global problem accounting for 1.6 m illion deaths in 2012 alone. With just 12% of the worldâs population and bearing 67% of HIV/AIDS burden, Sub- Saharan Africa is the m ost affected with large inter-country variations. Although Kenya has declining prevalence, some regions and sub-populations such as Nyanza and fishing communities still have prevalences more than three tim es the national average of 5.6%. Existence of high risk sexual behaviours such as concurrent sexual partnerships in the fishing communities are postulated to account for the high HIV prevalence of up to 25.6%. Thus, determining prevalence and determinants of sexual concurrency among m arried couples and the patterns of the resultant sexual networks is crucial in designing appropriate HIV interventions. Thus, this study aimed at establishing the prevalence, determinants, sexual networks, actor-partner effects and interventions to address sexual concurrency am ong married couples in the fishing communities along Lake Victoria in Kisum u County. This was achieved through a mixed methods cross-sectional study using 1090 gender-m atched structured interviews among 545 couples, 12 focus group discussions with 59 couples and, 16 in-depth interviews with eight couples. For the structured interviews, randomly sampled fishermen on each beach were contacted as index participants and asked to enroll into the study with their spouses. Quantitative data was analyzed using both descriptive statistics such as frequencies, percentages, means, medians, interquartile ranges; and inferential statistics utilizing Ï2 tests, logistic regressions and multilevel modeling. For qualitative data, the transcribed and translated transcripts were analyzed inductively based on grounded theory tenets for theme and content. The prevalence of sexual concurrency based on six months reference period was 33.1% among m en and 6.2% am ong wom en. One third (37.6%) of the couples were sexually concurrent (at least one spouse within the couple was involved in concurrency). Determinants of c ouple sexual concurrency were: unmet sexual desire, intra-spousal suspicions of infidelity, male dominance sex roles, domestic violence and relatively young unstable families. This study found no association between menâs concurrency status and non-concurrent spouseâs HIV status (p=0.91) or womenâs sexual concurrency status and non-concurrent spouseâs HIV status (p=0.20). The largest component in the sexual networks am ong these married couples had 108 people (nodes). The median component size was 5 (IQR, 4-6). A quarter (23.7%) of the components that had 3 m embers each had HIV positive couples. Similarly, 35.7% of the size 7 components had HIV positive couples. This study found evidence of actor and partner effects among m arried couples in respect to relationship and sexual satisfaction, mutuality in relationship and male dom inance sex roles. Couplesâ suggested interventions for sexual concurrency in this comm unity included: community education and sensitization, improving spousal communications, and instituting marital counseling. Married couples in these fishing communities have a high prevalence of sexual concurrency that may potentially result into formation of sexual networks within the reachable paths of HIV. It is recommended that communities re-introduce pre-marital and start periodic in-m arriage counseling to im part marital life and mutual respect skills in couples to help in reducing concurrent sexual partnerships. Future research should focus on designing longitudinal and com plete sexual network studies that enable better understanding of network structures and possible intervention options.Item Impact of community based ecotourism on householdsâ livelihoods and environmental management in Il Ngwesi and Lekurruki group ranches, Laikipia county, Kenya.(2014-08-20) Gaitho, Vincent GichuruThe rangelands in Kenya experience socio-economic challenges of poverty, low literacy, food insecurity, low incomes, unemployment and inequality in the context of environmental hardships of low unreliable rainfall, frequent and prolonged drought, poor soils, pest and diseases. They are conflict zones over pasture, space and water between local communities and between humans and wildlife. Indigenous communities here have developed land use diversification and livelihoods strategies such as Community Based Ecotourism (CBET) to cope with these challenges. CBET is a means of environmental conservation and livelihoods through the preservation of biodiversity and reduction of rural poverty. This study therefore focused on the impact of CBET on householdsâ livelihoods and environmental management in Il Ngwesi and Lekurruki Group Ranches in Laikipia County. Specifically, the study sought to establish the nature and level of householdsâ participation in CBET; examine socio-economic benefits to members; evaluate the effect on householdsâ livelihoods and on the conditions of resources and determine the overall challenges facing CBET. The study formulated two null hypotheses that sought to test the significant of CBET on householdsâ livelihood and on environmental management. Data were sought from both primary and secondary sources. Primary data were collected using questionnaires administered to purposively selected respondents who represented households; through interviews among key informants who were selected through snowball process and through Focus Group Discussions (FGDs) conducted among members representing different social units; and satellite imageries on vegetation cover changes. Secondary data were derived from publications. Data were subjected to qualitative and quantitative analysis while satellite imageries were analysed and classified using Erdas 9.1 and GeoVis 2.0 remote sensing softwares. To test the hypothesis, Chi-square (x2) tests were done; while to determine the viability of CBET, a SWOT analysis was conducted. The study found out that local communities participating in forums where decisions to introduce CBET were made; they gave space for conservation, elected officials and provided labour among other activities. It was also found out that group ranch members were entitlements to attend and participate in meetings where group ranch issues were deliberated on, had the right to information, to employment and to development projects emanating from CBET proceeds among others. From CBET members benefited from employment, security, bursaries in support of education, construction of schools, up grading of roads, transportation of members with ranch vehicles, water projects among others. Environmental benefits included protection of catchments, increased pasture in the conservancies, and regeneration of forests and increased wildlife population among others. Analysis on land use and land cover changes showed that areas under closed forest and shrubland had increased while those under grassland had decreased giving way to woody vegetation encroachment. The significance of CBET on householdsâ livelihoods was positive on welfare programmes, infrastructure development and education, while on environmental management; it was positive in forest and wildlife resources, and pasture. SWOT analysis indicated internal strengths and weaknesses as well as the external opportunities and threats of CBET which led to the conclusion that CBET was a viable venture in the study area. However, CBET faced challenges of misappropriation of funds, low community involvement, donorsâ domination, marketing and human-wildlife conflict among others. To mitigate the challenges, engagement of independent auditing of books of account to check on misappropriation, formulation of appropriate policies to govern donor-community partnership, recruitment and deployment of additional guards to contain human wildlife conflict among others were recommended.Item A Climate-Proof Response-Capability for Green Water Saving and Agriculture Resilience in Semi-arid Watersheds Of Eastern region, Kenya(2014-03-03) Cush, Ngonzo Luwesi; Shisanya, C.A.Climate change and deforestation are increasingly depleting the little âblue waterâ available in streams and groundwater in most tropical lands by increasing evapotranspiration and depleting plant water (âgreen waterâ). Green Water Saving (GWS) schemes are innovative pro-poor mechanisms suggested to mitigate climate risks and impacts, and alleviate poverty in Arid and Semi-Arid Tropics (ASATs). This study assessed: (i) past, current and future variations of the micro-climate and land use/cover in Bwathonaro and Muooni Catchments of Eastern Region of Kenya; (ii) the blue water balance in the selected catchments; (iii) drivers to farmersâ vulnerability to water disasters; (iv) efficient and effective adaptive strategies put in place by farmers to curb water disasters; and (iv) the cost-efficiency and recovery of investments in GWS schemes under conditions of drought and flood in a watershed. A quasi-experimental design was used to assess formal GWS schemes going on in Bwathonaro Catchment versus informal ones implemented in Muooni Catchment. Empirical tools of scientific research included a survey of 272 farms, 50 in-depth interviews, 2 Focus Group Discussions and an extensive literature review. Analytical techniques involved time series forecast of selected hydroclimatic variables and of the water balance from 1965 to 2030 using SPSS and MS Excel spreadsheets and the WEAP tool; LULCC spatial models using ILWIS and ArcGIS software; HERAM, VCA and VCA+ tools; SWOT, PESTLE and PMR analylitical tools; HEI and BCA mathematical models and CVM econometric models. Results indicate that Muooni catchment is re-greening though warming at 0.8 to 1.2oC in a century under the effects of agro-forestry and rainfed agriculture within what seems to be like a ânatural forestâ, while Bwathonaro experiences a cooling of more or less 2oC in a century triggered by high urbanization rates of 640% in 35 years. These trends are accompanied by decreased rainfall of about 30 to 50 mm per century and decreased discharges ranging from 0.01 to 0.05 m3/s. Consequently, the prediction of blue water balance revealed catastrophic situations by the year 2030, high rates of unmet water demands and low rainfall inputs undermining farmersâ innovations to worsen their vulnerability to drought. Though environmentally needed and socially accepted, GWS schemes are inefficient and unprofitable in agriculture, thus questioning their economic feasibility in Eastern Region of Kenya. To achieve high efficiency levels under any hydro-climatic condition, the study recommended (i) enhancing local watershed institutionsâ capacity; (ii) achieving a consensual agreement between upstream and downstream farmers to enable fair Payment for Watershed Services (PWS); and (iv) designing contingent water disastersâ plans.Item Effects of Climate Variability on Water Resources and Livelihoods and State of Adaptive Capacity in semi-arid Tharaka district, Kenya.(2013-08-12) Recha, Wambongo C. S.This study adopted an integrated approach of vulnerability assessment to understand climate variability and its effects in Tharaka District Kenya. The specific objectives of the study were: (i) analyze the characteristics of rainfall variabil ity; (ii) a ssess the effect of climate variability on water availability; (iii) d etermine the perceived impact of climate variability on livelihoods; (iv) Assess the conceptual understanding of climate variability in relation to other socio - economic stress ors and; (v) Assess the availability and use of attributes and indicators of adaptive capacity. The study utilized four data sets: daily rainfall data (1969 - 2007), household survey (N=326), interviews with practitioners (N= 24) and Focus Group Discussion ( N= 48). The study used cumulative departure index and rainfall anomaly index to establish rainfall trends for the period on record; and two sample t - test to establish the difference between March - May (MAM) and October - December (OND). Percentage cumulative mean was used to estimate mean dates of onset and cessation and INSTAT in disaggregation of daily rainfall data into pentads to analyze within - season characteristics. The study utilized X 2 to establish satisfaction levels of distance to water points, socia l amenities and rating of seasonal climate forecasts. Factor analysis was used establish the main effect of climate variability while participatory risk ranking and scoring to yield the lead stressors. In Tharaka, OND and annual rainfall are persistently b elow nor mal when compared to MAM. Rainfall has high inter - annual variability with occasions of positive anomalies such 1997 for OND and negative anomalies such 1984 for MAM. MAM and OND had a coefficient of variation exceeding 0.3 although the former was p oorly distributed in April . The average date s of onset were 21 - 25 of March and October , while c essation dates were May 16 - 20 for and January 6 - 10 for October - January season. But onset dates showed high inter - annual variability than cessation dates. MAM and OND seasons in Lower Midlands 5 and Lower Midlands 4 are markedly different and therefore require different cropping system s . Although 58% of households engage in more than three livelihoods, income derived is very low. Results of factor analysis show ed livestock (25%) and water & forest products (12%) as the most affected by climate variability. This perception was at variance with practitioners who said crops were the most affected. Water scarcity (1.2) and lack of money (1.2) had the highest sev erity index, ahead of irregular rains (1.7) and drought (1.5) as stressors. Awareness on the causes and impact of climate variability and the improved rating of climate forecasts should be harnessed into an opportunity to reduce vulnerability. Livelihood d iversity, land availability, two growing seasons and cultivation of drought tolerant crops are the indicators of adaptive capacity in Tharaka. Adaptation to climate variability is hampered by lack of credit facilities, low literacy levels and limited use o f climate forecasts. T here were institutions in Tharaka supporting adaptation through seed distribution, food relief, irrigation and rainwater harvesting . It is recommended that farmers in IL5 and IL6 tap the full potential of MAM season and stakeholders a ddress socio - economic concerns as a first step to strengthen adaptation . Future studies should quantify drought episodes and analyze the implications of rainfall variability on major crop yields in Tharaka.Item Enhancing Farmers'Agricultural Productivity Through Improved Field Management Practices in the Central Highlands of Kenya(2013-03-21) Ngetich, Kipchirchir FelixFarmers in central highlands of Kenya have been experiencing declining crop yields in the recent past. Low water availability caused by low and unreliable rainfall, and poor water harvesting techniques coupled with low soil fertility are key constraints to crop production in these regions. To increase crop yields, and reduce production risks, better use of available rainfall is required. The broad objective of the research was to enhance farmers' agricultural productivity through improved field management practices in the central Highlands of Kenya. The research was carried out in Maara, Meru South both in Tharaka Nithi County and Mbeere South district in Embu County. The study used both sociological and experimentation approaches. Long term rainfall and other meteorological data were utilized in the modeling exercise. A socioeconomic survey was conducted to explore how farmers make crop production decisions and 'ad~pt their field practices in response to seasonal rainfall distribution patterns. Tillage and surface management, timing of split nitrogen application and temporal staggered planting trials were conducted to assess their effect on maize yields and also to collect data for AquaCrop model parameterization, calibration and validation. T he field trials were complemented with a runoff study. The rainfall analysis study established the most probable onset, cessation and the length of growing season. Rainfall analysis resulted in establishment of spatial rainfall onset and cessation dates of the study area. Based on farmer's survey, key findings were on how the farmers adapted and also cope with not only rainfall variability but also climate variability. From the staggered planting trial results, dry planting led to 28%, and 37 % higher grain yields in Kiamaogo and Machang'a, respectively, compared to normal (wet) planting. Hence, it was observed that decision on the planting date, roughly going along with the start of the rains, is of utmost importance especially in low potential regions like Mbeere. Tillage methods and surface management study highlighted the impact of integrated approach in in-situ water conservation. For instance, even though therewas significant (p=0.05) influence of minimum tillage on soil water conservation with ift;1e,surface management strategies were more apparent within a short time and their influence on maize yields was significant. Split application of 70N proved to be the best application method leading to 18% grain yield increase compared to single application. The findings also underscored the potential use of calibrated AquaCrop model with a high degree of reliability; R2= 0.87 to 0.96 for combined observed and estimated grain and stover yields in Machang'a and Kiamaogo.AquaCrop model was recommended for use in practical management, strategic planning, and estimation of yield production under varying climatic and agro-ecological conditions. The runoff study clearly showed that under water limiting conditions, tied ridging was a very efficient technique in reducing sediment yield by 94% followed by mulching (73.5) compared to conventional practise (Bare surface). It was observed that conventional tillage accelerates soil loss as signified by high sediment yields irrespective of the rainfall pattern. The output of this study would be invaluable to extension service providers, governments, bureaucrats and people in regional natural resource management groups in planning, designing and evaluating effective and efficient soil and water conservation strategies at local, regional and national scales. This would in turn result in positive spin-offs in farmers' adoption of soil and water conservation practices.Item Sustainable resource management for improved livelihoods:The case of human-wildlife relations in Nyeri County,Kenya(2013-01-22) Mwangi, Pauline M.; Mahiri, Ishmael; Mutisya, DorothyThis study examined the nature and the pattern of Human Wildlife Conflict (HWC) in Nyeri County and the effects the management of wildlife resource has on human livelihoods. Nyeri County is rich in wildlife as it is sandwiched between the Aberdares and Mt Kenya National Parks. The objectives of the study were to assess the nature and the pattern of human-wildlife conflict in the study area, its impact on human livelihoods and wildlife conservation efforts with an aim to identify mitigating strategies that can improve the welfare of both. The study held the hypotheses that severity of human-wildlife conflict did not vary from place to place nor from one period of time to another. It also stated that the attitude of residents towards wildlife has no effect on management strategies. Primary and secondary data were collected. A questionnaire was administered to households and government officers in Nyeri County. A total of 686 respondents were sampled in addition to Kenya Wildlife Service (KWS) officers in the sampled locations. Data gathered were analysed using Statistical Package for the Social Sciences (SPSS). Chi-square test was used to examine the intensity of the problem. Satellite images showed land-use changes whereas Time-series analysis was used to identify the pattern of the conflict from 1950 to 2008 with an aim of finding the best ways to address it. An assessment of methods being used to contain HWC in the county was done in order to see their effectiveness, and identify areas that need improvement. Strengths, weaknesses, opportunities and threats (SWOT) helped assess the effectiveness of the various strategies used to deal with HWC in the area whereas Likert scale helped in assessing the views of stakeholders towards methods used to cope with wildlife problems and their perceived effectiveness. The study found that that the concept of HWC has different meanings among the respondents. Those who encounter problems from big wildlife experience more severe HWC than those encountering small wildlife. In the newly settled areas such as Thigu, all respondents (10%) reported problems from big wildlife while only 1.1 % reported such problems from Chinga, an old settlement area . . In the newly settled locations, HWC was found to have a great impact on human livelihoods and wildlife conservation than in the southern locations. For instance, 59% of the respondents were unhappy with the way KWS deals with HWC in their areas. Majority of such people with a negative attitude live close to big wildlife hence severe conflicts. With a growing human population migrating to wildlife habitats there will be continued competition of the scarce resources unless serious strategies are used to manage the conflict. Educating the residents on livelihood strategies compatible with wildlife can help improve both human livelihood and wildlife management. There is therefore a need for the government to revise some of the existing policies and practices on wildlife management in Kenya. The study concludes that HWC has an effect on livelihoods sustainability as well as on wildlife management and solution to this problem is necessary.Item Sociol-economic and agronomic factors influencing soil erosion in the Masinga Dam catchment, Kenya(2012-04-23) Mutisya, Dorothy Nduku; Mutiso, S. K.; Wamicha, W. N.This research examines agronomic and socio-economic factors influencing soil erosion in the Masinga dam catchments. The study addresses soil erosion from a human point of view as opposed to the common and widespread ''physical approach'' that has in the past been used by many scientists. The following two null hypotheses formed the basis of this research; (i). There is no significant difference in the amount of soil loss between farms under different agronomic practices; and (ii). There is no significant difference in socio economic status between farmers whose farms are experiencing less and severe soil erosion in the study. Three sets of data including socio economic, agronomic and soil loss were collected from Kaihungu and Mathauti Sub-catchments in the Upper and Lower parts of the Masinga Dam Catchments. A questionnaire was used in the collection of the socio economic data and part of the agronomic data. Crop cover was estimated by visual observation while crop density was calculated from crop spacing measurements taken in the field. Soil loss data was collected using 26 soil traps during the Long and Short Rainy Seasons of 1992. Composite topsoil samples were collected from the upper decimeter of 26 sites. These were used in the determination of soil texture and fertility. Two non-parametric tests namely, Chi-square (X2) and Mann-Whitney U test analysis, there was not a significant difference in the amount of soil loss between farms under different crops and cropping patterns. That is, soil loss was high in farms where monocropping or intercropping was practiced. Similarly, soil loss was high in farms with medium crop density as well as in those with low and medium crop densities. The explanation for these findings is that none of the sampled farmers practiced a combination of all the required appropriate agronomic measures. Many of them adopted one or a few of the good agronomic measures thus making soils vulnerable to agents of erosion. The Chi-square (x2) results reveal that a large number of the farmers (88%) whose farms had a severe soil erosion problem experienced numerous intricate socio-economic problems hindering them from practicing the recommended soil conservation measures. These results indicate that there is a significant difference in socio-economic status between farmers whose farms experienced less severe and severe soil erosion in the Masinga dam catchments. On the other hand, farmers experiencing severe soil erosion were poverty striken and resource poor. They owned small and fragmented farms, and had little or no access to extension services and credit and had little or no on-farm and off-farm income. On the other hand, however, the few farmers who did not experience severe soil erosion had relatively high on and off-farm incomes, relatively large farms, access to agricultural extension services and were generally highly educated. The implication here is that the progressive farmers have surplus land and working capital. These can be contrasted with the "resource poor" farmers who can hardly invest on soil and water management in their farms. Based on the findings of this study, it is recommended that sustainable short and long-term solutions to soil and water management problems among the resource poor farmers be sought. These should initially take the form of increased subsidies and incentives among the farmers. Also, it is paramount for academicians to conduct more research in order to monitor and quantify the rate of soil erosion in the entire catchments from bare grounds should also be determined.Item An analysis of the nature and extent of integration of Kenyas maize markets in trhe post liberalization era(2012-01-19) Wambugu, Stephen K.Although Kenya completely liberalized its maize market in December 1993, the country continues to experience frequent food shortages that greatly compromise the welfare of its citizens, more so the poor. In Kenya, food shortages are inextricably linked to maize, the major staple foodstuff. Persistent maize crises have sometimes manifested themselves in simultaneous existence of maize surpluses in some regions (North Rift and parts of Western Kenya) and maize shortages in others (Eastern and North Eastern Kenya). This scenario has placed great doubt on the nature and extent of integration of maize markets. This study analyses two major aspects pertaining to integration of maize markets in Kenya. These are spatio-temporal integration of periodic markets and effects of liberalization policies on maize prices. The study examines the spatial distribution of market places and market days and also describes the relationship between population density and market provision. The study further assesses the degree spatio-temporal integration (synchronisation) of periodic markets. The study also presents a comparative assessment of the constraints female and male traders face in their maize trade. Another aspect that this study examines is the degree of integration of surplus and deficit maize markets. The study also evaluates how integration has been affected by liberalization policies. The study finally tests for Granger causality between maize markets. Two complementary approaches were utilized in addressing the research theme: a quantitative analysis of spatio-temporal location of markets and maize price data and a qualitative inquiry into the constraints maize traders face. Data processing, analysis and presentation utilized the following techniques: computation of Rn values, correlation analysis, comparison of empirical results with the model of maximum synchronization of markets with a three day market periodicity, computation of summary statistics, frequencies, computation of measures of dispersion, cointegration techniques, Granger causality tests and use of percentages. This study found that market places and market days are significantly uniformly distributed as indicated by the Rn values. A consideration of the underlying projected 2003 population in the sampled districts led the researcher to conclude that this regular spatial arrangement is an efficient pattern to serve the consumers. An analysis of the spatio-temporal integration of the periodic markets revealed that the marketing system favours the consumers more than the itinerant traders. This hampers proper movement of maize and other commodities from the areas of surplus to the areas of deficit by the itinerant traders. The activities of the itinerant traders, as integrating agents, are hampered by a number of infrastructural, institutional and policy constraints. The study further found. out that female traders are more constrained than male traders in conducting maize trade. Cointegration analysis among spatially separated markets both in the pre- and post-liberalization eras revealed that liberalization policies have improved the transmission of price signals among various markets in the country, thereby strengthening the links between them. Granger causality tests revealed that strong central markets have emerged in the major production and consumption zones. On the basis of the findings of this study, some useful policy recommendations are made. First, efforts should be made to synchronize market places and market days, establish new market places and market days and establish complimentary institutions. This could foster the integration of the rural economy leading to development. Secondly, efforts should be made to improve transportation and communication infrastructure, storage facilities and market facilities. Other recommendations include developing and implementing grading and standardisation of maize, establishing an effective and efficient agricultural market information system, establishing and promoting maize and other grain traders, dealers, transporters and processors associations, devising a special credit policy especially for female traders and other market participants, providing short and long term training to various stakeholders in the maize industry and devising and implementing a gender sensitive maize marketing policy.Item Modification of the microclimate in a changing tropical urban environment: the case of Nairobi city(2012-01-05) Makokha, G. L.The main focus of this study was to examine both the long and short-term modification of Nairobi City's microclimate resulting from its changing urban environment. The specific objectives were to: (a) determine the temporal changes in environmental factors affecting climate; (b) determine the long short-term changes in the microclimate as a result of changes in (a) above; (c) establish how specific land use types modify some climatic variables within the urban canopy layer (UCL); (d) model the influence of topography and land use on wind flow pattern. To achieve the above objectives both secondary and primary data were used. A combination of cartographic, numerical and statistical techniques was employed to analyze the data. The results of the study established that the city of Nairobi has experienced phenomenal growth in population, built environment, manufacturing industries, number of motor vehicles and consumption of energy. It was also established that as these aspects of the Nairobi urban environment change so does its microclimate. Using the linear regression model, it was established that rates of annual temperature change over the study period of 34 years (1966-1999) were found to have higher coefficients of determination (r2) for minimum temperature than for maximum temperature. The Mann-Kendall rank statistics established that the warming trends with significant U (ti) values of greater than 2 were observed at the urban stations than at sub-urban stations. Seasonally, the hot dry season represented by the month of January and the warm wet month of November were found to have both significant warming trends for minimum temperature and cooling trends for maximum temperature, an indication of the existence of both the urban heat island and cool island respectively. The cool dry month of July and the hot wet month of July and the hot wet month of April were found to have insignificant and lower U(ti) values for both maximum and minimum temperatures. The daily temperature differences between urban and sub-urban stations were found to be greater for minimum temperature during the dry month of January. The highest daily difference in minimum temperature of 3ÂșC was experienced between urban MABE station and sub-urban JKIA station during the dry month of January; an indication of the intensification of the urban heat island in the hot dry period. Cooling/Warming temperature rates were found to be highest during the dry hot period and lowest during the dry cool period. The highest cooling rates were recorded at the suburban station while the lowest at the urban station. Significant trends in annual seasonal specific humidity at 0600 and 1200 GMT were found to exist at the urban stations, having U(ti) values greater than 2, while no trends were established at the suburban stations. The t-test values for the diurnal differences in specific humidity between the urban stations were found to be significant at 95% confidence level. Regression analysis of annual and seasonal rainfall amount using the suburban/urban ratios established that both increasing and decreasing trends were found to exist in Nairobi City. In the wet month of April, the trends of all the ratios between suburban stations and urban MABE station had negative slope values with higher r2 values, an indication of the urban influence on long-term rainfall amount. On the daily differences in rainfall days, amount and intensity, among the urban and suburban weather stations, topography was found to influence the number of rainfall days, while urbanization exerted an influence on rainfall amount and intensity. A simulation of the wind flow pattern over Nairobi area under the influence of topography and various land use categories established that easterly wind flow was predominant during the months of January, April and November. In July southerly and Southwesterly winds were found to be predominant. Surface wind flow was found to stagnate as it flows over the built-up areas, the central business district (CBD) and the relatively steep slopes to the west of Nairobi. Wind channeling was also found to exist along river valleys to the northwest and southeast of Nairobi. The findings of this identified some implications concerning climate and urban planning for Nairobi City. Specifically planners should put in place policies and strategies that enhance the creation of an urban environment that is climatically safer, healthier, less polluted and physiologically comfortable. To realize this, the study recommended that continuous and systematic monitoring of urban land use change that impact negatively on the microclimate of Nairobi City should be undertaken. There is need to continuously make observations and measurements of the relevant climatic variables by improving on and increasing the number of existing weather station network, and using both auto-traverse and satellite-based techniques to regularly monitor changes in the microclimate of the city. Research in computer simulation models applicable to Nairobi City should be undertaken to understand to understand both the wind flow and energy balance dynamics that prevail within its urban boundary layerItem Environmental impact assessment of soil and water resources in the watershed of lake Nakuru(2012-01-03) Murimi, Shadrack KianaThe study assesses the extent of change in some hydrological and geomorphological aspects within Lake Nakuru catchment area. To achieve this, trends in the climatic elements of rainfall and evaporation, and how they relate to falling water levels of the lake and its feeder rivers for the period 1967 - 2003 were investigated. In addition, spatial distribution of relative relief and land cover in each l km2 grid were used to map potential soil erosion in the drainage basin. Stream network extent, computed from drainage densities were used to establish the sediment transport capacity for rivers draining into the lake. Cyclic and non-cyclic visual determination of trends in climatic and hydrologic components was computed by use of various analytical techniques. Time series analysis using regression lines and running averages were computed to examine any cyclic events in the trends. In addition to this, analysis of seasonality patterns was also calculated to establish month to month variabilities in the trends. Characteristics of extreme low flow events in the downstream direction of River Njoro (which has the major inflow into Lake Nakuru) were computed by use of frequency and probability analysis of recurrence intervals. ArcView Geographical Information Systems (GIS) algorithms were used to compute spatial distribution of areas with topographic potential for erosion and directional derivatives of surfaces representing sediment transport routes. To do this, a combination of satellite imagery (SPOT) and topographic maps were used to compute spatial distribution of land cover/use, slope steepness and drainage densities in the Lake Nakuru basin. Runoff potential for each land cover/slope combinations were computed in a grid based analysis to classify potential soil erosion characteristics in the basin. Digital Elevation Maps (DEM) and unit stream transport power analysis were integrated, to visually reveal potential delivery of sediments into the lake. Findings emerging from the study indicate that only trends of lake levels are significant. This means that water levels of Lake Nakuru have been falling for the period 1967-2003. It was not possible to relate the decrease in lake levels to trends in climatic elements for the last 37 years. Both annual rainfall amounts and 5 - years running averages reveals a fairly stable cyclic pattern. Evaporation amounts on the other hand, show moderate variability though the trend was found not to be significant. Seasonal distribution of rainfall totals was found to have a significant relationship with stream discharges of River Njoro. Consideration of downstream changes in stream flow along the river portrayed different scenarios. The study reveals that during the dry seasons, flow past certain points along the river is decreasing despite an apparently unchanging rainfall regime. This was not the case for wet seasons. The results led to the conclusion that during dry conditions other factors like, surface and subsurface abstractions, contribute to lower flows as the river approaches the lake. In addition, analysis of low flow characteristics indicate that the proportion of time for which given flows were equalled or exceeded continues to decrease towards present. The increase in human population and continued encroachment into forests and grassland areas and fragmentation of farms is believed to be responsible for the low flows in rivers draining the watershed of Lake Nakuru. Results from GIS mapping and modelling indicate that a change in the land cover/use on slopes has a direct effect on the hydrological set-up of the Lake's watershed. Potential soil erosion was found to be high in the steep headwater region compared to other areas of the drainage basin. A consideration of existing records and field observations indicate that headwater regions have experienced recent encroachment of agricultural fields into forest zones. Drainage density in the steep headwater zones is also high, hence high sediment transport capacity. The study concludes that sediments transported through the streams are contributing to siltation thus reducing the capacity of the lake to hold water. The foregoing events can be used to predict and hence plan changes in sediment production and transport to save the Lake. This could also guide in the formulation of policies that are geared towards management of soil and water resources in Lake Nakuru basin and others with similar land use scenarios.