PHD-Department of Environmental Science

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Influence of land use and land cover changes on groundwater recharge and pollution in stony Athi Subcatchment, Kajiado County, Kenya
(Kenyatta University, 2023) Mathenge, Morris Wahome
The global economic growth and population increase has translated into increased anthropogenic land use and land cover changes. Changes in land use and land cover have the potential of altering the hydrological cycle. In the Stony Athi sub-catchment of Kajiado County, Kenya, demographic pressure and urbanization have transformed natural rangelands into agricultural, industrial and real estate developments. The objective of this study was to investigate the influence of land use and land cover changes on groundwater recharge and pollution vulnerability between 1984 and 2017. Specifically, the study was undertaken to; (a) quantify the spatial-temporal extent and magnitude of land use and land cover changes that have occurred in Stony Athi subcatchment between 1984 and 2017; (b) to estimate the spatial-temporal variations of groundwater recharge due to land use and land cover changes; and (c) to evaluate the influence of land use and land cover changes on groundwater vulnerability to pollution. Quantification of spatial-temporal extent and magnitude of land use and land cover changes was achieved by classifying four satellite images through the supervised classification algorithm and finally applying post-classification change detection technique. Results showed significant (p < 0.05) land use and land cover changes between 1984 and 2017 with an increase in built-up areas (0.04% - 3.4%), agricultural land (0.06% - 0.7%) and grasslands (58.2% - 71.6%), but a decrease in shrub land (37.1% - 21.1%) and forested areas (2.5% - 1.4%). Estimation of the spatial-temporal variation of groundwater recharge due to land use and land cover changes was done using WetSpass-M, a Geographical Information System-based Hydrologic Model. Results indicated a decrease in groundwater recharge from 13.8% in 1984 to 13.2% in 2017. However, the observed temporal variations were not significant at p < 0.05. Spatial variations of groundwater recharge indicated that the highest recharge occur in forested areas at 251.1 mm per year while the lowest recharge occur in bare land at 0.4 mm per year. A modified DRASTIC model was used to evaluate the influence of land use and land cover changes on groundwater vulnerability to pollution. Potential of groundwater pollution vulnerability was categorized using a vulnerability index based on the United States Environment Protection Agency classification. Results indicated that 87% of the study area remained under low vulnerability between 1984 and 2017. Areas under moderate vulnerability decreased from 12% to 9% while areas under high vulnerability increased from 1% to 4% over the same period. The observed temporal variations in groundwater pollution vulnerability were not significant at p < 0.05. It was concluded that the land use and land cover changes in the study area have an influence on groundwater recharge and its vulnerability to pollution, though not statistically significant at p < 0.05. This study recommends continuous monitoring of groundwater quantity and quality, not only in the study area, but also in areas undergoing rapid changes in land use and land cover. Such monitoring will contribute to sustainable groundwater resource management. Future research could focus on other factors, which might affect groundwater dynamics in the study area such as climate change.
Intraseasonal Rainfall Variability and Climate Change Adaptation in East Africa
(Kenyatta University, 2021) Ogega, Obed Matundura; James Koske; James B. Kung’u
The study assessed historical intraseasonal rainfall variability, generated future intraseasonal rainfall scenarios, and made recommendations to build on climate service foundations for a sustainable climate change adaptation in East Africa. First, an assessment of the performance of regional climate models (RCMs), participating in the Coordinated Regional Climate Downscaling Experiment (CORDEX), in simulating East Africa’s spatio-temporal precipitation characteristics was done. Using a set of eight descriptors of East Africa’s precipitation, the RCM assessment was done to determine the best model runs for evaluating East Africa’s historical and future precipitation characteristics. The descriptors are the consecutive dry days (CDD), consecutive wet days (CWD), simple precipitation intensity index (SDII), mean daily annual (ANN), seasonal (March to May, MAM and October to December, OND) precipitation, and representatives of heavy precipitation (90p) and very intense precipitation (99p) events. Specifically, (i) nine reanalysis data (ERAINT)-driven and (ii) 24 model runs from five general circulation model (GCM)-driven CORDEX-Africa RCMs were analysed. Relatively better performing RCM runs were then used to assess projected precipitation changes (for the period 2071-2099 relative to 1977-2005) over the study domain under the representative concentration pathway (RCP) 8.5 scenario. Results showed the performance of RCMs to be descriptor- and scope- specific. Overall, RCA4 (r1i1p1) forced by CNRM-CERFACS-CNRM-CM5 and MPI-M-MPI-ESM-LR, REMO2009 (r1i1p1) forced by MPI-M-MPI-ESM-LR, and RCA4 (r2i1p1) forced by MPI-M-MPIESM- LR emerged as the top four RCM runs. Further, an ensemble mean of the top four model runs outperformed an ensemble mean of 24 model simulations and ensemble means for all runs in an RCM. An analysis of projections showed a reduction(increase) in mean daily precipitation for MAM(OND), an increase(decrease) in CDD(CWD) events, and a general increase in SDII and the width of the right tail of the precipitation distribution (99p-90p). An increase in SDII and 99p-90p implies a possibility of heavy and extreme precipitation incidences by the end of the 21st century. Examples of how the climate information generated from the analysis could be used in various sectors were made. First, an assessment of historical and future rainfall variability over Kilifi County, a typical coastal community whose primary source of livelihood is rain-fed smallholder farming, was done. Using climate information and data from the social survey on the farmers’ perceptions of climate variability, adaptive capacity, and adaptation activities, an innovative climate change adaptation model was co-developed with smallholder farmers to help build the farmers’ adaptive capacity in Kilifi and beyond. Secondly, the study assessed the potential impacts of global warming scenarios of 1.5 oC and 2 oC on malaria transmission in East Africa. Under the two warming scenarios, results showed an imminent increase in seasons and geographical extents of malaria transmission in East Africa. The study recommended intensification of efforts to sustain the gains made towards malaria elimination. Lastly, a status review (in terms of climate, population, and land-use change over Nairobi metropolis) was done, and recommendations made to help safeguard the future of Nairobi National Park. Overall, the thesis findings provide essential information to support the region’s climate change adaptation and mitigation efforts for sustainability.
Anthropogenic Impacts of Land Use and Land Cover Changes on Mai Mahiu Ecosystem, Nakuru County, Kenya
(Kenyatta University, 2020) Basweti, Caleb Ntabo
Land-use changes are the main cause of human and environmental problems especially in many developing countries in Africa and Asia. Study was conducted in Mai Mahiu, Nakuru County, Kenya whose aim was to assess the impacts of land-use and cover changes on the ecosystem functioning and human environment. Specific objectives were: (i) to understand the nature of land use practices (ii) to monitor impacts on soil quality; (iii) impacts on vegetation composition and structure; (iv) to examine the level of variation in the physico-chemical parameters of rivers; and (v) to assess the effect of land-use change on climatic variability. GIS technology was used to establish landuse/cover changes from 1985 to 2015. Soil samples were collected for physical and chemical analyses from five land-use practice namely; undisturbed forest, disturbed forest dominated by Croton spp., disturbed forest dominated by Tarchonanthus camphoranthus, cropland and severely grazed grassland while Transect method was used for vegetation survey. Water was sampled at four sampling stations (A, B, C and D) which are sites where the river passes through the above mentioned land-use practices and analyzed for physico-chemical parameters while climate data was used in climatic variability analysis. Analysis of variance, regressions and mean separation at 0.05 significance level were excuted on the data using GenStat 14th edition. Results showed a remarkable land-use and land-cover change between 1985 and 2015. Cropland significantly increased by 135% from 27.3 km2 in 1985 to 64.2 km2 2015 at the expense natural forest. Built-up area and roads coverage had increased by almost three times from 9.8 to 29.9 km2. Soil quality deteriorated significantly with land conversions. There were significant changes in soil bulk density (p<0.001) that ranged from 0.93 g/cm3 in undisturbed forest to 1.27 g/cm3 in severely grazed grassland, soil pH (p=0.002), soil organic carbon (p=0.008) with losses of up to 63%, and total nitrogen (p=0.005) that ranged from 0.15 to 034%. Vegetation was stratified into three layers with shrub stratum being dominant replacing the tree layer that was dominant in 1985. Physico-chemical characteristics of river water deteriorated along sampling stations, A to D in both dry and wet seasons. Water pH, temperature, turbidity and conductivity increased along sampling stations A to D (p<0.001) while flow velocity and dissolved oxygen decreased significantly (p<0.001). Chlorides, sulphates, nitrates, phosphates calcium, iron, magnesium, potassium and sodium were significantly higher (p<0.001) at stations C and D compared to stations A and B. There was no significant difference in long-term annual rainfall variability (p=0.685). Intra-annual rainfall variability was noticed in the months of March, April, May and November (p>0.001). The study concluded that land use change and modifications in Mai Mahiu have negatively affected the state of the Mai Mahiu ecosystem. For the sake of the present and future generation in the region, the study recommends restoration and rehabilitation through landscape based land-use practices, enforcement of laws and implementation of policies relevant this type of ecosystem.
Impacts of Decentralized Governance on Forest Conservation and Community Livelihoods in Kakamega and Loita Forests, Kenya
(Kenyatta University, 2018-12) Mũsingo, Tito Edward Mbuvi
There is a global trend towards decentralizing the management of forests. Forestry decentralization in Kenya is relatively new with enabling legislation having been promulgated in 2007. The impact of decentralization on forest management and livelihoods has not been adequately studied. The study overarching aim was to assess the impacts types of forest governance on forest conservation and community livelihoods, analyse the institutional factors that support and constraint decentralization of forest governance and recommend how to appropriately implement decentralized forest management in Kenya. The study was conducted in three sites: community regime in Loita Forest, full government control (government regime) in Kakamega Forest National Reserve (KFNR) and Participatory Forest Management (PFM) regime in Kakamega Forest Reserve (KFR). Households adjacent to the forests under study were randomly selected and questionnaires administered. Recall questions were administered to households in the PFM regime in order to attribute any observed livelihood impact at household level to PFM; Key informants from government departments as well as local and international non-governmental institutions were interviewed. Changes in forest condition and area over the last 30 years were determined through interpretation of satellite images using fragmentation analysis and confirmed through ecological studies. Data were analyzed using descriptive, parametric and non-parametric statistics and evaluated at P=0.05 level of significance. Chi-square tests and simple linear regression were conducted to explore perceived decentralization management scenarios and to check the relationship between quantity of resource accessed and distance into the forest as well as other quantitative characteristics of the household respectively. It was observed that promulgation of The Forests Act, 2005 revised to The Forest Conservation and Management Act (2016) was a bold step that signalled the start of decentralization of forestry governance in Kenya. The households in the government regime (84.5%) and the community regime (78.2%) indicated that the forest was better managed compared to 55.7% in the PFM regime. Joint community and government management individually did not contribute optimally to better forest management but it was perceived to have more benefits. The households and policy-makers respondents indicated that there was change in forest condition with the community noting a significant decrease of forest size across the different forms of management (χ² = 27.614, p<0.05). This was confirmed by satellite images analysis. Though the government regime approach was good for biodiversity conservation, it contradicted concepts of sustainable development, does not enhance equity and impoverish communities. In the PFM regime, the policy-makers indicated forestry management was under decentralization (87.2%) and PFM was the major management approach (58%) applied in Kenya. Though the study indicates that each regime was appropriate in its own context, PFM regime was indicated to be the preferred regime because it: facilitates better forest management and improved household livelihoods; ensures that the five types of property rights are not the preserve of one stakeholder; was drifting towards devolution; was facilitating the subsidiarity principle and does not negatively impact on the greater common good; was empowering the partners at all levels; ensures the communities have tenure rights over some forest products and there are incentives in place to manage the forest sustainably. The PFM regime ensures the State decentralize power to Community Forest Associations (CFAs). It confers legitimacy through election of CFA by members whom they all interact with and whom they are accountable to. This enables the community to build social capital necessary for better forest management and improved household livelihoods.
Evaluating payment potential for environmental services and watershed conservation of Thika Dam, Murang’a County, Kenya
(Kenyatta University, 2018-05) Kimenju, Kagombe Joram
Payment for Environmental Services is a concept that is increasingly being adopted as anincentive-basedapproach in natural resource management. It links the suppliers and consumers of environmental goods and services in a way that both parties can contribute to improved delivery. The main environmental goods and services traded are carbon, biodiversity, aesthetics and water. The predominant attitude towards watershed management in many parts of the world is that water will always flow from the catchment for free and there is therefore no urgency or incentive to institute sustainable use of land and water resources. As a result, farmers lack inadequate knowledge, incentives and recognition of their role in provision of water to the rivers. Nairobi City has been experiencing serious water shortages in the past years resulting in water rationing. Thikadam supplies 80% of water to Nairobi city but few of the users of water are able to link availability of clean water in their pipes to conservation of water catchments areas. The objective of the study was to find out how land owners and users of water from Thika dam can participate in watershed protection scheme through Payment for Environmental Services. Specifically, the study identified land use changes in the catchment area for the last 30 years and its effects on water quality and quantity;factors that could influence willingness of water users to pay for the environment services; environmental services the farmers are willing to adopt; economic incentives the buyers were willing to give to farmers in return for their conservation efforts and policies and institutional framework that are necessary for PES. Primary and secondary data were collected based on baseline survey and qualitative research approaches, interview schedules, questionnaires, focus group discussions and analysis of satellite imagery followed by ground truthing. Both parametric and non-parametric methods of data analysis were used. Results showed that land use practiceshave changed over time with tea coverage increasing by 11% at the expense of woodlots. Chemicals used in water treatment hasincreased with increasing rainfall. Farmers are also willing to accept improved farming practices in return to incentives though their expected incentives were far above what the users are willing to give. Incentives in kind were most preferred (50%) followed by community projects (33%) and cash incentive (17%). Consumers preferred giving community projects (48%), support in kind (38%) and cash incentives (15%). There was a significant relationship between consumers source of water and willingness to pay. Consumers who are connected with water from the Ndaka-ini catchment area werewilling to give more. However, there was no framework in which consumers willing to pay could use to provide incentives to the providers of environment services. Further results showed a gap in institutional framework for PES and lack of supporting legal institutions. The findings of this study can lead to better management and conservation of catchments areas leading to improved water quantity and quality of Thika dam. The findings of the study can be used by the government to develop a payment of environment service model for Thika dam and other water catchments areas in the country.
An Evaluation of Integrated Soil Fertility Management Practices in Meru South District, Kenya.
(Kenyatta University, 2007-10) Mugwe, Jayne
Farmers in the central highlands of Kenya do face problems of low crop yields due to soil fertility decline. This is as a result of continuous cropping, nutrient losses through crop harvests, soil erosion and leaching coupled with inability to replenish the soil through use of external inputs. The situation is aggravated by poor adoption, among farmers, of improved soil fertility management options. This study investigated feasibility of using integrated soil fertility replenishment technologies (SFRT) involving organics in combination with inorganic fertilizer to improve soil fertility and consequently crop yields in Chuka, Meru south district. The organic materials evaluated comprised of two leguminous trees (Calliandra calothyrsus and Leucaena trichandra), two herbaceous legumes (Mucuna pruriens and Crotalaria ochroleuca), Tithonia diversifolia, a locally available tree shrub, and cattle manure. Effect of these organic materials (sole or combined with inorganic fertilizer) on maize yields and soil properties (pH, macronutrients, inorganic nitrogen) was assessed under both on-station and on-farm experiments. Farmer adoption surveys were carried out to assess adoption process that included technology preferences and farmers‟ experiences, as well as household and farm characteristics determining decision to adopt or not to adopt SFRT. All biophysical data were subjected to ANOVA and means separated using LSD at α = 0.05. Social data were subjected to descriptive statistics and summarised using means, frequencies and percentages. Factors influencing adoption were subjected to multivariate regression analysis. The on-station experiment showed that treatments that had sole application of the organic materials at 60 kg N ha-1 , and organic materials (30 kg N ha-1 ) plus inorganic fertilizer (30 kg N ha-1 ) gave similar yields (p≤0.05). However, these treatments recorded higher maize yields than that from sole inorganic fertilizer treatment. They maintained maize yields at 4 to 6 t ha-1 and should therefore be recommended for use by farmers, who currently get 0.5 to 1.5 t ha-1 from their conventional farming systems. Herbaceous legumes gave the lowest yields among the organic resources, but performed better than the control treatment. At the onfarm trials, maize yields from researcher designed and farmer-managed trials were less variable than those from farmer designed and managed trials, which was attributed to differences in management practices among farmers. The organic materials had a positive contribution to soil pH, K, C and N while cattle manure showed superiority in terms of its contribution to soil properties. The amount of soil inorganic N within the plow layer and N-uptake by maize monitored during 2002 LR and 2004 LR seasons showed variation among the treatments, sampling periods, and between the seasons. There were high amounts of soil inorganic N at 0-15 cm soil depth at the beginning of the season, followed by a decline from around 4 to 8 weeks after planting. This trend was attributed to rapid mineralization of the incorporated organic materials and “Birch effect” that was followed by leaching, due to intense rainfall, coupled with uptake of N by the maize crop. Treatments that had tithonia, calliandra and leucaena applied had the highest soil inorganic N in most sampling periods and also the highest cumulative N uptake by maize. It was evident that the effect of external inputs on N uptake was dependent on climatic conditions (especially rainfall) prevailing throughout the growing period. Poor rains during 2004 LR resulted in accumulation of soil inorganic N and restricted N uptake by the maize crop. There was high residual inorganic N at 100-150 cm soil depth that was probably due to greater N mineralization compared to plant uptake in the top-soil immediately after the onset of the rainy season and subsequent nitrate leaching. This inorganic N observed in the 100-150 cm depth is below the rooting zone of most maize plants and may not be available to the maize crop. The study established that first farmer preferences were SFRT involving manure and tithonia combined with fertilizer followed by fertilizer alone and was attributed to easy accessibility and probably low opportunity cost of practicing these technologies. Technologies that combined organic and inorganic fertilizer were more popular among farmers and farmers used them on significantly (p≤0.05) larger plots than with application of either sole organics or inorganic fertilizer. Farmers developed innovations that involved mixing of organic materials, which gave high yields possibly due to increased nutrients supply and other benefits associated with organic materials. The main benefits reported were increased crop yields and fodder (calliandra and leucaena) and this could have been a driving force to the adoption of the technologies. The major constraints were high labour demand and inadequate biomass and farmer tried to cope by preparing land early, applying materials without chopping and planting trees near the crop fields. Five factors were identified to significantly (p≤ 0.1) influence adoption. Age of household head and number of mature cattle negatively influenced adoption. Farm management category, ability to hire labour and number of months in a year households bought food for the family positively influenced adoption. The odds in favour of adoption increase by a factor of 0.9 for households hiring labour, while households buying food for more than three months in a year have an adoption probability of 25%. The implication of these results is that adoption of improved SFRT could be enhanced through targeting of young families where both spouses work on farm fulltime, food insecure households and farmers who lack access to other sources of soil improvement such as those without enough cattle to produce manure. This study has filled an important gap by providing a recommendation on some appropriate technologies for replenishing soil fertility by smallholder farmers in Meru South District. The role of cattle manure in increasing soil fertility parameters was well demonstrated and due to its easy accessibility in the region, it is likely to remain one of the key resources for managing soil fertility. It is therefore recommended that factors that seem to limit its performance especially on farms such as low quality be addressed. The study also showed how farmers test and manage new soil fertility management innovations to meet their livelihood objectives, and identified factors crucial for enhancing adoption of integrated SFRT. The government therefore needs to strengthen, expand and support long-term soil initiatives that aim at enhancing adoption of these technologies. Policies and institutional support should be focussed on enhancing willingness and ability of farm households to adopt the technologies while taking into consideration key factors that were identified to influence adoption in this study. Further research is recommended on the follwing areas: residual effects on soil of low and high quality organic resources, partitioning of N upon decomposition of these resources, tradeoffs of biomass banks on farms and their economic viability, diffusion and potential of up-scaling of integrated soil fertility management technologies in the area.
Zai pits and integrated soil fertility management enhances crop yields in the drier parts of Tharaka Nithi County, Kenya
(2017) Kimaru, Serah Wairimu
Low crop yields due to low erratic rainfall, high evapotranspiration, and deteriorating soil fertility in smallholder farmers‘ fields of sub-Saharan Africa have led to a quest for sustainable production practices with greater resource use efficiency. To alleviate water stress, soil fertility decline and reduce runoff, water harvesting technologies and integrated soil fertility management (ISFM) are alternative promising options whose impact on agricultural productivity are not yet clear. The study therefore aimed to assess the effect of using zai pits in combination with organic/inorganic ammendments and conventional cropping technique on sorghum production. Effects of zai pit and conventional cropping techniques combined with integrated soil fertility management (ISFM) (organic materials as sole or combined with inorganic fertilizer) on selected soil physico-chemical properties and sorghum yields were assessed in a field experiment. Economic performance of all the treatments was evaluated using standard enterprise budgeting techniques to determine production costs and profitability. Descriptive statistics, chi-square, paired t tests and binary logistic regression were used in analysis of socio-economic data. Experimental data were subjected to analysis of variance and mean separation done using least significant difference (LSD) at p<0.05. The results of the study indicated that number of non-formal trainings, beneficiaries of NGOs, membership of group and visits by non-governmental extension agents play an important role in adoption of zai pits. Manure application led to a significant (p=0.014) increase in pH and a significant (p=0.05) increase in nitrogen under zai pit. The aggregate stability of zai and sole tithonia (ZT) was significantly higher (p=0.03) than conventional planting with sole tithonia (CT) at the end of the experiment. High volumetric water content (VWC) was recorded at the depth of 35 cm for zai treatments compared to conventional treatments. Zai pit in combination with tithonia amendment had the highest yields of 4.3 Mg ha-1 during short rains season of 2013 (SR13) while zai pit in combination with cattle manure had the highest yield of 4.18 Mg ha-1 during short rains season of 2014 (SR14). During the SR14, grain yields of zai pit with cattle manure (ZC) were significantly (p=0.016) higher by 53.7% compared to conventional planting with cattle manure (CCM). Conventional planting with full rate NPK (CF60) had the highest benefit cost ratio (BCR) of 3.58 while zai pit without input (ZNO) had the least BCR of 0.94. The experiment showed that zai pit technology contributed to increments of grain and stover yields in comparison to conventional planting although its BCR was lower than conventional planting with similar amendments. Based on the findings, there is need for agricultural policy makers to develop and implement appropriate agricultural guidelines for extension service providers and smallholder farmers on the effectiveness and efficiency of the technologies in the study. This will enable small holder farmers to make informed decisions on adoption of the technologies as a coping mechanism to climate change, enhancement of food security and alleviation of poverty in in the semi-arid tropics in Sub Saharan Africa
Pupils' understanding of the concept of environment: a case study of standard seven pupils in Nyanza Province, Kenya
(Kenyatta University, 2005-12) Otewa, John Odhiambo
The study, resulting into this thesis, was based on the awareness that humanity's survival and prosperity depend on the finite resources and life supporting systems (e.g. water, air and soil) all of which are rapidly deteriorating from the surface of the earth. This awareness was first echoed in 1972 at the International Conference on Human Environment at Stockholm and later incorporated into the school curriculum in the member states through the recommendation of Tbilisi Conference of 1977. In Kenya, formal infusion of environmental concepts into the school curriculum, from primary to tertiary levels, started in 1985. But, since environmental degradation has continued unabated, threatening the well being and sometimes the very survival of life on earth, there seemed to be a deficiency in the implementation process of such infused environmental concepts in the school system. In an attempt to investigate the causes of this deficiency, this study endeavoured to provide answers to the following questions: what prior knowledge did Standard Seven pupils have on the concept of environment before it was formally taught; and did the prior knowledge have effect on the pupils' understanding of the concept when it was formally taught as outlined in Standard Seven science course? The study focused on pupils' understanding of environmental principles, namely: meaning of environment; components of environment; pollution of environment and conservation of environment which are included in the topic "Our Environment" in Standard Seven science course. The study involved 288 Standard Seven pupils, eighteen head-teachers, eighteen Standard Seven science teachers and twelve cultural opinion leaders from Gusii and Luo communities. Various research instruments were used to I investigate the target population's perception of the environment, including Environment Apperception Test (EAT) for pupils and Interview Schedule for cultural opinion leaders. The findings of the study were that: the pupils' prior knowledge of the concept of the environment was that environment is constituted by a single component of the wider environment, for example water, soil, air, plants or animals; the sources of the pupils' perception included the pupils' communities' perception of environment and the schools' presentation of environmental concepts in the school curriculum from Standard One to Six; and that the pupils' prior knowledge affected their understanding of the concept when it was formally taught to them under the unit "Our Environment" in Standard Seven science course. The Study therefore recommends that the curriculum development, the teaching and evaluation of environmental concepts in the school curriculum be systematic. This implies that different concepts of the environment are to be taught in different classes in the school system accordingly and the content be evaluated comprehensively so as to draw the attention of the examiners, the teachers and the learners on the concepts of environment infused in the school curriculum.
Effects of selected tree species on socio-economic benefits and sustainable land management within agro-ecosystems in Kitui County, Kenya
(Kenyatta University, 2015-10) Kurauka, Joseph Kathiai
Dryland ecosystems are increasingly becoming recipients of human populations, which is a response to highland pressure and land scarcity in the arable zones. Despite strong evidence linking benefits of agroforestry with community livelihoods, there is a dearth of studies linking farmers' experiences of those benefits with sustainable land management options. This study was therefore carried out to assess effects of selected tree species on socio-economic and environmental status of aggregated communities of Kitui agro-ecosystem in Kenya. Further, the study sought to: determine the relative importance of tree species integrated into crop production systems in Kitui Central Sub-County; assess the socio-cultural, economic and ecological value of selected tree species in different agro-ecological zones in Kitui Central Sub-County; examine farmers' experience in selected agroforestry tree species and their impact on soil fertility in selected agro-ecological zones in the study area; assess the effects of these tree species on household livelihoods; and evaluate environmental benefits and challenges of tree species integrated in crop production systems in the study area. The research methods used in this study included: a baseline survey, 18 focus group discussions and in-depth farmer interviews, tree cover measurements, soil sampling and testing, and GIS map analyses. In addition, a survey design employed formal methods of socio-economic data collection such as use of questionnaires, interview schedules, and direct observation. Other data sources included publications ranging from local project reports to international journal articles, books, global databases and digital libraries. Soil sampling of soil at the depth of 40cm deep. Soil samples collected from various sites were analyzed for macro and micro-nutrients following standard laboratory procedures. Data were subjected to analysis of variance and using LSD (p < 0.05). The hypotheses tested showed that there was no significant differences in benefits mainlyfuelwood, timber, fodder and fodder of the main tree species on the farms except Senna siamea (%2 =32.1, df =30, p=0.03). Farmers indicated that tree species such as Acacia spp., Adansonia digitata, Cordia africana, Croton macrostachyus, Croton megalocarpus, Erythrina abyssinica, Melia volkensii, Sesbania sesban and SchefJlera actinophylla are highly recommended, therefore, being some of the most promising indigenous tree species in agroforestry systems. Other tree species are highly recommended by farmers for agroforestry systems are Calliandra calothyrus, Senna siamea, Grevillea robusta and Sesbania sesban. However, farmers interviewed mentioned that a number of tree species introduced in the area are reducing soil fertility and causing decline in crop productivity in their farms. The respondents further confirmed that the following tree species negatively affected soil fertility in their farms: Azadirachta indica, Casuarina equisetifolia, Cupressus lusitanica species, Eucalyptus species, Grewia bicolor, Mangifera indica, and Sclerocarya birrea. Therefore, this study concluded that, indigenous and some exotic tree species are highly valued for improved household status through sale of wood products, provision of fodder for livestock and improved soil fertility. This study recommends the need for key stakeholders to formulate policies that enhance establishment of appropriate and fast-growing tree species that could lead to improved livelihoods and enhanced soil fertility. This would ensure success in tree species choice, therefore, significantly contributing to sustainable ecological and socioeconomic benefits for agricultural farms in arid and semi-arid lands. Keywords: agroecosystems, agroforestry, sustainable livelihoods
Economic Analysis of Climate Change Adaptation Strategies at Community Farm-Level in Ijara, Garissa County, Kenya
(Kenyatta University, 2015) Mwaura, Joseph
The semi-arid Ijara sub-county borders Fafi sub-county to the north, Lamu and Tana River counties to the south and west respectively and republic of Somalia to the east. It occupies agro-ecological zones IV to VI, that change to V and VI, moving away from Boni forest with an estimated 1000km2 arable land suitable for crop agriculture. Temperatures range 15ºC – 38ºC with average relative humidity 68%. Rainfall data from Kenya Met Services 1970-2008 indicated shift from the traditional trend to erratic and definite decline. However recent predictions across models showed positive rise in both precipitation and temperature year 2030 onwards along the coastal belt where study sites locate. But, the high temperature-induced evapotranspiration annul gains from rainfall increases. The climatic changes expose the area to shocks arising from frequent drought and flooding. Given the shocks that outwit traditional coping mechanisms, farmers spontaneously took to water harvesting pans, Aloe crop and pasture enterprises as adaptation strategies. The spontaneity translated into unclear costs and benefits which the study clarified by isolating them for analysis and measuring the strategies‟ viability for adaptation. Significance of the assessment was reduction of existing data scarcity and informing climate-smart agriculture productivity and realization of the most valuable policy results. Costs-benefit-analysis was the design used, complemented by the financial market-driven 15% discounting rates and net present values. Also co -ordinated regional ordinated regional ordinated regional ordinated regional ordinated regional ordinated regional ordinated regional downscaling experiment downscaling experiment downscaling experiment downscaling experiment downscaling experiment downscaling experiment downscaling experiment downscaling experiment downscaling experiment downscaling experiment downscaling experiment models were used to ascertain climate performance and projection. Household questionnaire was administered to 240 sample size calculated from 9000 farmer population. Based on the sample size, households in Handaro, Sangole-Ijara and Bothai were randomly selected for interview. Results showed 57% pastoralists had embraced agro-pastoralism to incorporate Aloe, and on-farm rain-fed Sudan grass, whose input costs were Kshs 120,000/ha/season with estimated yields of 1.8 tons/ha of dry matter. Cash flow across three rainash flow across three rain ash flow across three rain ash flow across three rainash flow across three rainash flow across three rainash flow across three rain ash flow across three rainash flow across three rain ash flow across three rainash flow across three rainash flow across three rain ash flow across three rain -fed fed fed seasons netted Ksh seasons netted Kshseasons netted Ksh seasons netted Ksh seasons netted Ksh seasons netted Kshseasons netted Ksh seasons netted Ksh s 1,925,091, 4,069,234.55 and 6,103,851.83 per hectare from one, two and three seasons respectively. Overall net present value was Kshs 180,041p.a. Equal to 50.5% agro-pastoralists produced fodder that cushioned against the high costs on inter-county importation. Land size inadequacy and the communal tenure upset 86.26% producers whereas 47.5% were concerned that drought raised production costs the most after that lack of skills 53.08%, feed deficit at 30.41%, and diseases 20.41% in that order. Aloe crop netted Kshs 37,500/ha/season. The benefits compared favorably with investment of Kshs 125,000/ha given that some capital costs e.g. fencing were one-off. Annual water pan cash flow netted present value Kshs 512,349.25. Overall benefits from the three strategies exceeded costs, making the investment viable for adaptation. Going forward and considering the limited adaptation capacities, disease control and feed deficit costs, policies need to focus on formulating livestock improvement guidelines to include revitalizing traditional grazing management practices. Other pertinent investment opportunities include strategic value-chain linkages and infrastructure, promotion of rain-fed and irrigated fodder production technologies incorporating climate-smart water harvesting. Equally crucial is enriched soil stabilization using multi-benefits crops e.g. Aloe, supporting post-harvest feed reserves technologies, reviewing land tenure system and investing in local farmer-friendly weather data collection and application.
Assessment of Heavy Metal Contamination in Masinga Reservoir, Kenya
(Kenyatta University, 2015) Nzeve, J. K.
In Kenya, monitoring of heavy metal pollution is a priority area of research since their concentrations in aquatic ecosystems affect the fish industry which is a major source of livelihood. Therefore, an assessment of heavy metal contamination (Cu, Zn, Pb, Cr, Mn and Cd) in sediments, water and in three selected fish species (Cyprinus carpio, Clarius gariepinus and Oreochromis spirulus niger) in Masinga reservoir was carried out between January and December 2013 in five sampling sites. Physical parameters (water temperature, dissolved oxygen, pH, turbidity and electrical conductivity) were measured on site. Heavy metal Concentrations were determined using atomic absorption spectrophotometry. The data obtained was analyzed using one way analysis of variance and significant differences accepted at p ≤ 0.05. Tukey’s HSD test was used to separate means. The mean values for the physical parameters ranged from 24.93 – 27.530C (water temperature), 4.66 - 5.36 mgL-1(DO), 41.50 – 64.23NTU (Turbidity), 109.79 – 125.98μS cm-1 (EC) and 7.51 – 7.88 (pH). The results revealed significant difference only in water temperature (p =0.044). Mean heavy metal concentrations (mg kg-1) in sediments were Cu (11.38 – 23.67), Zn (60.04 – 75.84), Pb (11.14 – 14.47), Cr (21.39-49.62) and Mn (259.12 – 642.30). There were significant differences in metal concentrations for Cu (p =0.00), Cr (p=0.00) and Mn (p=0.00) among the sites. Surface water from different sites did not show significant differences in heavy metal contamination (p > 0.05). The mean metal levels (mg kg-1) in Cyprinus carpio muscle tissues were in the range of Cu (0.519 – 1.422), Zn (39.466 – 62.233), Pb (0.994 – 1.424), Cr (0.324 – 0.709) and Mn (0.660 – 1.432). There was significant difference in Zn (p=0.006) and Mn (p=0.001) in Cyprinus carpio muscles at different sites. In Clarias gariepinus muscles, mean metal concentrations (mg kg-1) were Cu (0.677 – 0.974), Zn (32.929 – 37.205), Pb (0.643 – 0.078), Cr (0.516 – 0.858) and Mn (0.452 – 0.990). Pb exhibited significance difference between the sites (p=0.026). Mean values for heavy metals in Tilapia (mg kg-1) for different sites were Cu (0.515 – 0.782), Zn (29.645 – 37.999), Pb (0.552 – 0.765), Cr (0.559 – 0.791) and Mn (0.183 – 1.480). Only Mn showed significant differences between the sites (p=0.00). Pearson matrix correlation analysis showed some significant correlations among the heavy metal levels in water, sediments and different fish species. Bioaccumulation transfer factor (TF) calculated showed that water had higher TF compared to sediments. The concentrations for all metals in surface water did not exceed the WHO recommended limit for drinking water. In sediments and the three fish species they were also lower than WHO set limit except for Cr. Results from this study demonstrate the need for an ecosystem approach towards sustainable management of reservoirs. This will curb aquatic pollution which is a health risk to people consuming aquatic resources contaminated with heavy metals.
Influence of Climate Variability on Coastal Small-Scale Fishing Communities in Kenya
(Kenyatta University, 2015) Akunga, Beatrice Ghettuba
Globally, fisheries support the livelihoods of over half a billion people. Around 90% of the 38 million people recorded globally as fishers are classified as small-scale. Small-scale fishers are considered vulnerable to the negative impacts of climate variability and change. There is limited understanding of how climate variability currently affects the livelihoods of small-scale fishing communities in Kenya. This study investigated the extent of climate variability in Mombasa and Malindi in Kilifi County and its influence on fish catches and the livelihoods of fishing communities. The study also examined the coping mechanisms developed by small-scale fishing communities; factors influencing their coping strategies; institutional capacities to deal with current and future climate extremes; and the perceptions of small-scale fishers on fish abundance and influencing factors. The study adopted a descriptive study design. Stratified random sampling was used to select a sample of 218 fishers from a total population of 240. Primary data were collected by use of semi-structured questionnaires, interview schedules, direct observation and Focus Group Discussions. Data were analyzed statistically (p<0.05). Pearson Correlation was used to analysis the correlation between sea surface temperature, rainfall and fish catches. The analysis yielded an inverse correlation between sea surface temperature and fish catches (parrot fish r= -0.565; cavilla jacks r= -0.431; shark r= -0.481); and a positive correlation between fish catches and rainfall (parrot fish r=0.159; cavilla jacks r=0.237 and shark r=0.220). In terms of livelihood assets, results of the study showed no significant association (χ² =36.27, df=36, p=0.456) between gear type andeducation level. Spearman correlation analysis between gear type and income level showed a strong interaction (r=1.00, p<0.05). Results of binary logistic model of selected variables established that education level (Wald =0.013, df=1 p=0.909) and period in fishing (Wald=0.017, df=1, p=0.895) were not significant determinants influencing migration as a coping strategy to climate variability. However, age, (Wald=6.614, df=1, p=0.01), and vessel ownership (Wald=5.003, df=1 p=0.025) were. Education level (χ²= 8.346, df =6, p=0.214; age χ²= 1.323, df=2, p=0.516) and period in fishing (χ²=1.210, df=6, p=0.976) had no significant association with using the same gear but fishing inshore as a coping strategy. Ordinal logistic regression model indicated that level of education (Wald= (0.960, 0.004, 0.593) with associated p-values of 0.327, 0.948, 0.441 and experience in fishing (Wald= (0.002, 1.690, 0.092) with associated p-values of 0.965, 0.194 and 0.761 were not significant determinants that influenced the perception of fishers on temperature variability, being a key factor that influences fish abundance. However, age (Wald= 12.150, p= 0.000) was. The study recommends increasing fishers access to educational, physical, financial and livelihood opportunities to help reduce their vulnerability to the adverse effects of climate variability.
Analysis of Biogas Technology for Household Energy, Sustainable Livelihoods and Climate Change Mitigation in Kiambu County, Kenya
(Kenyatta University, 2015-01-21) Muriuki, Salome Wamuyu
Domestic energy insecurity is a major threat to sustainable development in Sub Saharan Africa. Across the region, the fundamental role that firewood and charcoal plays in the social and economic welfare of many households cannot be overemphasized. This study aimed to assess the role of biogas technology in saving wood, mitigating green-house gases emissions, and in improving livelihoods in Kiambu County. Oral interviews, Focused Group Discussions, and Action Learning Case Studies were used on biogas adopter and non-adopter households. Participatory experimental research was carried out using selected farmers’ installed bio-digesters of different designs and sizes. Cows were fed on nine different feed combinations and the biogas yield from these cows’ dung tested for CH4, CO2 and H2S contents. Gas was analyzed using portable Biogas Analyzer 5000 (Geo-tech UK). Fuel consumption and expenditure patterns was determined using household surveys. Carbon emission reduction was calculated from fuel consumption reduction with biogas use, and presented in CO2 equivalent. Impact of the technology on livelihoods was analyzed using DFID (1999) framework on sustainable livelihoods. Data was analyzed using SPSS and SAS computer softwares. ANOVA revealed variation in gas quality from different cattle feeds. Descriptive statistics, tests of significance (t-tests and chi-square), and logistic regression were used to establish relationships between variables. There was high likelihood of biogas adoption with combination of independent variables age, education level, farm size and the number of cows owned. The technology showed great potential and real benefits for uplifting livelihoods. Significant financial savings were realized, with an average household saving about KShs 38, 676 (455 USD) annually upon shifting to biogas energy. Time savings (up to 5 hours weekly) was highly significant. Health of user households also improved tremendously with absolute reduction in smoke, and improved sanitation around the home environment. From a livelihood perspective, biogas energy technology gave adopter households’ essential assets (human, physical, natural, social and financial) that enabled the households achieve positive livelihood outcomes. Among these assets, financial capital was probably the most resourceful. Wood consumption reduced immensely with biogas use. An approximate 303.8 metric tonnes firewood and 229.4 metric tonnes of wood from charcoal being conserved annually by biogas adopters. This combined helped mitigate approximately 1,079 tonnes of CO2 equivalent from being emitted to the atmosphere. Type and size of digester did not significantly influence gas quality. However, gas quality was markedly influenced by cattle diet. A high protein feed, gave a combined optimal effect on CH4 and CO2 emissions. The highest methane yield was achieved from chicken dropping (64.2%) and fodder legumes (63.8%). The technology therefore offers a myriad of environmental benefits and is a major driver of livelihoods in Kiambu. Efforts and resources are needed to increase widespread adoption of the technology
Determinants of the Biodiversity Conservation-tourism Nexus in the Buffer Zone of Amboseli Biosphere Reserve, Kenya
(2014-02-24) Mwakima, Margaret Wawuda; Njuguna, Steven G.
Tourism is an important ecocomic sector that generates billions of dollars all over the world. In Kenya, tourism is an important economic sector, contributing nearly 12% of the country’s Gross Domestic Product. The main resource base of this sector is a rich cultural and biological diversity. Despite the significance of tourism sector, its contribution to biodiversity conservation is not well understood, yet the two should be planned in an integrated manner. This study sought to establish the contribution of tourism to biodiversity conservation in Amboseli Biosphere Reserve. The specific objectives were to assess the threats to biodiversity conservation, to evaluate the effects of wildlife displacement by tourism infrastructure, and to determine the opinions of the local community on the effects of land use change, sustainability of biodiversity and tourism in the study area.This study was conceptualized on the premise that biodiversity conservation can be supported through wise stewardship and management of species and ecosystems. In order to achieve the research objectives, a stratified random sampling design incorporating both descriptive and analytical approaches was adopted. Field observations, interview schedules and questionnaires were used to gather data on biodiversity management practices, development of tourism infrastructure, threats to biodiversity and tourism; and opinions of local community about benefits from tourism and land use change. The results from 447 respondents, reviews of existing documents and field vists showed that changing land use, human encroachment, hunting for bush meat and game trophy, human-wildlife conflict and growing infrastructure development, including fencing were major threats to biodiversity in the buffer zone of Amboseli Biosphere Reserve. About 68% of the respondents were concerned that infrastructure associated with tourism development was displacing wildlife and disrupting their movement and behaviour. There were also no significant differences in the opinions of local community regarding the effects of land use change on biodiversity and tourism in the wildlife buffer zone around the park. A majority of the responses (83%) of the land owners and tourism related business owners were of the opinion that sustained favourable economic returns and effective community involvement in biodiversity conservation and tourism development were fundamental. This was necessary because the more attractive economic activities, such as land leasing to external developers and crop farming in the ranches increased human-wildlife conflict by restricting their movement to access to water and forage, especially during the dry season. The socio-demographic trends of local community and the changing values attached to land and wildlife are likely to influence the future of biodiversity conservation and tourism in Amboseli Biosphere Reserve. Group ranch owners and all the stakeholders should form mutually beneficial partnerships so as to sustain biodiversity conservation, tourism and livelihoods of the local communities.
Developing responsible environmental behaviour through formal school curriculum: the case of Kajiado, Kiambu and Nairobi Districts of Kenya
(2012-09-12) Karembu, Margaret Gathoni
The acquisition of responsible environmental behaviour through the school curriculum has more often been inferred than researched. Literature search on the subject indicates that more studies have focused on the status of environmental education (EE) than on its outcome especially regarding impact on the learners. The relatively early stages of development that formal EE finds itself could explain why institutionalised evaluation systems have not yet emerged. However, given the acknowledged role that EE could play in the pursuance of sustainable development, an assessment of how well environmental educators have faired in preparing the youth as environmental stewards is crucial. Given this scenario, this study set out to evaluate the quality of EE taught in formal school curriculum in terms of its ability to develop responsible environmental behaviour among learners. The study specifically focused on the contribution of the school towards this responsibility while acknowledging the existence of a multiplicity of other selected non-school factors such as the neighbourhoods, gender and environmental information sources. An attempt was also made to gauge teachers' perceived preparedness to teach EE. The respondents were finalists of the first tier of education (standard eight pupils) from public schools in Kenya. The study design was ex-post facto while the approach was that of a comparative case study of urban and rural settings commonly found in Kenya. Three districts Kajiado for low potential rural agro- ecological zone, Kiambu for high potential rural agro-cological zone and Nairobi for urban zone represented these settings. A number of sampling techniques were used starting with stratified sampling to select the study sites, systematic random sampling to choose 45 schools and simple random sampling to pick the 450 respondents. Data were collected with the use of questionnaires, interview guides and checklists, which were reinforced, with photographic sceneries of selected environmental conditions existing in both rural and urban settings. The data were computer-analysed using the Statistical Package for the Social Sciences (SPSS). The major finding of the study was that the general school approach to EE that has assumed a linear relationship between knowledge, understanding and behaviour has not been successful in developing responsible behaviour on a sufficiently large scale. While there is no denial that some achievement has been made, the findings indicated that learners were inadequately prepared to translate the expressed high levels of environmental knowledge and sensitivity into responsible action at personal level. The results revealed many inconsistencies between what pupils believed they should do and what they actually did. Levels of participation in environmental conservation activities were found to be low. The learners attributed this to overloaded curriculum, feelings of helplessness, lack of environmental role models and the linking of environmental activities with punishment, among others. Although the school was rated highly as an environmental information source, the mass media was also found to play a significant role. In general, urban pupils were more involved in environmental activities than their rural counterparts and recorded higher levels of knowledge on environmental problems and their solutions. Gender did not have an influence on levels of participation but showed significant influence on environmental concerns. Majority of the teachers felt inadequately prepared and incompetent to teach EE which was compounded by lack of relevant instructional materials; limited understanding of the scope and content of what constitutes EE; lack of time and funds for field trips. At the policy level, mechanisms for reinforcing EE curriculum were found to be weak, while inconsistencies were noted between a school's day-to-day practice and its operational curriculum. From the findings, it is recommended that the EE curriculum should incorporate and provide opportunities for learners to acquire skills for translating awareness into action. Environmental activities should not be used as modes of punishment as these create a negative image about EE. Values and attitudes espoused in the school should be reflected in the day-to-day behaviour of teachers and support staff as well as at the community level to model responsible behaviour. Environmental action learning should be core to a whole school's approach to EE and should be reinforced through care of the school grounds throughout learners' school life. The curriculum also needs to be reviewed to avoid duplication and release time for practical activities in EE. In-service training of teachers on methodologies of using school grounds and neighbourhoods in providing learners with hands-on experiences should be mounted, while the pre-service curriculum should be reviewed to put EE in its proper perspective. At the policy level, a mechanism to reinforce EE should be put in place, which can be achieved through school-to-school, child-to-child environmental inspections and organising annual environmental awards. In View of the above, further research is needed in a wider context of the geographical locations in Kenya. Other areas requiring further research include: methodologies of using the community as an effective tool for environmental action learning; enhancing the teaching of environmental matters through the school curriculum and how the mass media could effectively deliver EE in view of the study findings.
The performance of selected tree species in the rehabilitation of a limestone quarry at East African Portland Cement Company land Athi River, Kenya
(2012-04-12) Gathuru, G.; Mwakio Tolle; Obiero Anyango
Quarrying for limestone is an economic necessity that is not only hazardous to human but also one that invariably has deleterious effect on the environment. Information on the performance of trees species is important as plants are key in the revegetation of exhausted quarries. A comparison of field performance of Acacia xanthophloea, Schinus molle, Casuarina equisetifolia and Grevillea robusta was made in an exhausted limestone quarry, backfilled with limestone mine waste, in a semi-arid area, in Athi River, Kenya, between 2005 and 2008. The aim of the study was to assess the performance of the above tree species and to determine if these tree species had an influence on the soil physical and chemical properties. The seedlings were produced in a nursery and transplanted in plots established in the exhausted quarry site using randomised complete block design. Growth performances were estimated by measuring; tree height, diameter at the stem base (BD) , and diameter at breast height (DBH) from March 2006 to March 2008. The soils physical and chemical parameters measured were: moisture content; organic matter; pH; total Nitrogen; total Phosphorus and exchangeable cations. The study revealed that the time-species interaction was significant (p<0.001), indicating continuous tree growth for all the species. The trees species performance was varied. C. equisetifolia recorded the highest growth increments for the; height (525.3 em), BD (7.42 em) and DBH (4.94 em) and the highest growth rates for; tree height (14.24 cm/month), BD (0.23 em/month) and DBH (0.l4 em/month), indicating superior performance. This was followed by A. xanthophloea and S. molle. Grevillea robusta showed poor performance and recorded the lowest growth increments for; height (231.7 em), BD (4.41 ern) and BDH (2.0 ern) and growth rate for; tree height (5.04 em/month), BD (0.084 em/month) and DBH (0.023 em/month). These results indicate that there is species-specific response that may be due to different water- and nutrient-use strategies and growth patterns. The soil had low soil moisture content which ranged from 0.67% to 2.3%; alkaline pH, ranging from 8.0 to 8.98; low soil nitrogen content « 0.03%), related to the limited soil organic-matter content (ranging from 0.05% to 0.38%), and high to moderate exchangeable cations. All the tree species had a noticeable influence on soil chemical properties, by the end of the research period. The pH values and total Phosphorus were relatively lower in soils close to the tree row (0.5 m) and increased with distance from the trees, while the soil values for organic matter, total Nitrogen, and exchangeable cations were relatively higher close to the tree row and decreased with distance from the trees. From the study, C. equisetifolia has the best growth performance and also has a higher positive influence on the soil properties followed by A. xanthophloea. The two species are therefore recommended to be used in the rehabilitation of limestone quarries in similar semi-arid conditions.
Role of school based clubs in addressing environmental threats in the Nile Basin, case of Jinja District, Uganda
(2012-04-12) Nderitu, Ruth Wanjiru
This study sought to examine the different ways in which secondary school based clubs in Jinja District, Uganda addressed Nile basin environmental threats. The ultimate goal of the study was to enhance secondary school based clubs capacity to address the environmental threats in Uganda effectively. Primary data was collected through use of questionnaires, Focus Group Discussions (FGD), photographs and observation methods from selected secondary schools. Secondary data was gathered from records and literature in the Ministry of Education and Sports, schools, National Environment Management Authority (NEMA) Uganda, Non Governmental Organizations (NGOs) and internet. Appropriate descriptive and inferential analysis was done. Results indicate that there were several secondary school based clubs in Uganda. They included national clubs, subject based and religious organizations. Majority of the student respondents joined the clubs through invitation by their friends, wanted to participate in environmental issues or were curious to know what was going on in the club. The clubs collaborated with local communities, NGOs, government, other school based clubs and neighbouring schools. The clubs frequently carried out cleanups, tree planting and discussions and most club members participated in these activities. Local communities were sensitized on energy saving, deforestation, hygiene and proper waste management through seminars. The study revealed that clubs mostly addressed threats related to unclean water, deforestation and environmental diseases. However, they rarely addressed issues related to destruction of breeding sites, over fishing, damming, growth of waterweeds, reclamation' of wetlands, siltation of dams and flooding. Clubs were useful in creating awareness, advocacy, conservation, maintenance of school environment and in projects establishment. The clubs also helped to establish relationships, built leadership skills and brought unity in the schools. Major challenges to the school based clubs were financial, poor timetabling of the clubs' activities, lack of motivation and necessary facilities among others. The study recommends increased funding, training on Environmental Education (EE) and integration of EE in secondary school curriculum. Other recommendations include support from government and school administration, encouraging collaboration and partnership, motivation and positive reinforcement, adherence to time allocated for the clubs, establishment of projects to raise funds and provision of facilities and equipment such as trips and literature among others.
Influence of household environment on child morbidity and mortality in slums: a case study of Mathare and Soweto, Nairobi
(2012-01-20) Keraka, M.
Child mortality and morbidity disparities continue to be observed in this era of improved expansion of the provision of health care services. Some areas have low rates while others have high. The observed patterns are attributed to uneven distribution of health facilities, which guided the choice of study sites, namely Mathare and Soweto slum areas in Nairobi. The study objective of the study was to assess the perception and awareness of slum dwellers about the influence of household environment and behaviour patterns on child morbidity and mortality, given the available health, information and education service inputs. The study hypothesis was ''Households whose women believed that their children were more susceptible to child sickness in the environment they lived in and who had a positive perception towards a healthy behaviour were likely to be negatively correlated to child morbidity and mortality''. The methods that were used to collect data were: structured questionnaires, interviews, focused group discussion (FGDs), documentary information and observation methods. The study targeted women aged between 15-49 year who had children under 5 years of age. A total of 599 women from the study area were included in the sample. The Cluster sampling technique was applied. The main methods of data analysis for estimating child mortality were the Coale and Trussel techniques, ordinary least squares regression, the binomial distribution and descriptive techniques. A key finding of the study is that the probability of a child dying at exact age 2 (q2) values for Soweto and Mathare slums were estimated as 69.9 and 64.9 deaths per thousand live births respectively, while the estimates of the probability of dying at exactly age 5 (q5) values were 105.3 and 146.7 deaths per thousand live births, for Soweto and Mathare slums respectively. These values are high compared to the national values that have a q2 and a q5 of 60 and 96, respectively. The behavioural variables that were significant and positively correlated with child loss were: self-administration of medicine, incomplete immunization, type of medical treatment sought and level of toilet cleanliness. The psycho-social variable that was significant and negatively correlated to familial risk to child deaths was the perception of household residential arrangement as consisting of wrong people and being over-crowded. Those that were consisting of wrong people and being over-crowded. Those that were significant and positively correlated to familial risk to child death include; pre-natal clinical attendance and water quality status. The household variable that was significant and positively correlated to familial risk of child deaths was household size (7+). The individual variables that were significant and positively correlated to familial risk to child loss were; households whose women were aged between 35 and 49 and did not belong to any denomination. The study findings show that those households that had higher familial risk to child loss were mainly poor and had negative attitude towards modern medicine, and generally had low hygienic standards. The study recommends that public awareness on proper hygienic standards should be advocated. Also, the government should undertake training of the required health workers who will later be deployed into these areas (slums) in order to improve the living conditions. The Nairobi City Council should mobilize social and health workers to educate slum dwellers on proper hygiene and sanitation (outreach services), while there is need for a strong legislation guiding house construction and other social amenities.
Biophysical evaluation of sand encroachment and nebkha-dune stabilisation in North Horr, Marsabit district, Kenya
(2012-01-04) Olukoye, Godfrey Alati
Nebkha dunes, formed by the trapping of sand around the body of a plant, provide habitats for small fauna and are thus, important in the conservation of biodiversity in desert ecosystems. Many authors have reported results on investigating of nebkha dunes in the Kalahari, Sahara and Namib deserts of Africa. In contrast to this, scant information exists on the nebkha dunes of the Chalbi semi-desert region of Northern Kenya. Besides, land degradation in arid rangelands resulting from sand encroachment has to be evaluated within the framework of climate-vegetation-livestock interactions. However, no study has particularly focused on the dual role of vegetation for economic (livestock-production) and ecological functioning in nebkha dune stabilisation in Kenya. A study was therefore, designed to investigate theoretical and empirical issues related to sand encroachment and nebkha-dune stabilisation in North Horr, Northern Kenya. The study focused on soil and vegetation degradation as the main biophysical indicators of land degradation in North Horr. Satellite images taken at four points in time (1976, 1986, 1996 and 1998) were evaluated and complemented with field vegetation surveys. This enabled the assessment of the origin, history and extent of the process of sand accumulation in North Horr. Growth performance of different indigenous and exotic tree and shrub species was also evaluated in terms of height, relative growth rates and mortality. These were collectively used in assessing the suitability of exotic and indigenous trees and shrubs in dune stabilisation. Soil chemical and physical analyses were carried out and related to sand encroachment. Wind erosivity indices that give an indication of potential wind erosion hazard and sand movement potential were derived from wind speed data collected between July 1999 and September 2000. The Gabra camel production system involves involuntary culling of the mature breeding females at 300 months while both fattening male and female camels are culled at 58 months. These parameters were incorporated into a range utilization model and a bio-economic model-PRY for the assessment of ecological and economic trade-offs in the utilization of Suaeda monoica for dune stabilisation and camel browsing. The results of the simulation modelling were explored and linked to the problem of sand encroachment. Sand dunes in North Horr were predominantly of the nebkha type and were preferentially aligned with the predominant wind direction during the dry season. The morphonetry, orientation and textural examinations of the nebkhas suggested that fluvially deposited sand in North Horr, had in the recent years been reshaped by aeolian activity. Empirical evidence showed a positive correlation between wind speed and sand movement potential, which varied between month and time of the day. Average monthly wind speed of 3.99±0.06 m/s, with absolute maximum wind speeds of 10 m/s, implied that wind erosivity and sand-movement potential in North Horr were high, indicating increased soil degradation. Nebkhas showed heterogeneity in their morphomettry attributed to differences in plant species cover. For instance, in terms of length, there was a decreasing order of Hyphaene coriacea (16.36±3.23m), Acacia tortilis (5.10±0.20 m) and Suaeda monoica (3.20±0.68 m). Large nebkhas were, therefore, found in the southern and western parts of North Horr settlement dominated by Hyphaene coriacea (doun palm) and Acacia tortilis. Hyphaene coriacea is, therefore, the most important tree trapping large volumes of sand. However, due to the less compact (diffuse) growth form of Hyphaene coriacea, the trapped sand is loose and therefore, highly mobile when compared with that of Suaeda monoica with a more compact growth form and a denser canopy. Percent soil organic carbon was used to evaluate fertility status. The decreasing order of fertility beneath the different trees/shrubs were: Acacia tortilis (0.24%). Hyphaene coriacea (0.21%), Suaeda monoica (0.14%), Prosopis chilensis (0.12%), Acacia goetzei (0.11%) and bare ground (control) (0.09%). Although there were no significant differences (P<0.05) in soil organic carbon between vegetation types, it nevertheless demonstrated the differential abilities of plant species for land rehabilitation in North Horr. In additional, nebkhas could probably represented a large and significant storage of nutrients within the dryland system of North Horr. Multi-temporal analysis of statelite imageries (1976, 1986, 1996 and 1998) showed that the area (in ha) covered by bushland, degraded bushed grassland, degraded grassland, denuded bushland and open bushland decreased significantly (p<0.05) by 11.38%, 0.19%, 3.22%, 0.39% and 7.54% respectively. Over the same period, the area (in ha) covered by grassland and exposed land covered with sand, gullies and rocks increased significantly (p<0.05) by 15.25% and 8.51% respectively. This indicated progressive increase in area covered with sand. The greatest increased in the are covered with sand was recorded between 1976 and 1986 (7.08%) and the lowest between 1996 and 1998 (3.34%). There were corresponding dynamics in coefficient of variation (CV) in annual rainfall betwen 1976 and 1998 with the highest and lowest variability being recorded for the period 1976-1986 (56.42%) and 1996-1998 (33.64%) respectively. Correlations between land cover and rainfall were significant (p<0.05). Empirical evidence presented in this study suggested that exogenous stochastic factors (climatic) were primarily responsible for land cover dynamics and the concomitant localized degradation in North Horr. Simulation modeling with PRY showed that camel population in Stuaeda monica vegetation complex was not viable. Therefore, stochastic forces could also be responsible for the imbalance in supply and demand for Suaeda monoica forage by camels. However, with appropriate culling policy, a sustainable balance in the economic and ecological functions of Suaeda monoica could be achieved. It was concluded that participatory nebkha-dune stabilisation would only be possible if economic aspects of the Gabra pastoralists were taken into consideration. These findings have important implications for policy in the sustainable management of natural resources in arid rangelands for both economic and ecological functions. To rehabilitate saline soils and stabilise sand dunes in North Horr, emphasis should be placed on the used of indigenous tree and shrub species. Although fencing and enclosures encourage natural regeneration of vegetation, the viability of fencing for large-scale land rehabilitation in a nomadic pastoral system is questionable. Natural vegetation regeneration could, therefore, be the most cost effective, fastest and easiest method for stabilizing dunes in North Horr. The management of important dune stabilizing plants such as Suaeda monoica, an important camel forage, through natural regeneration is, therefore, significant in ensuring that it performs both the economic and ecological functions. This option is compatible with the pastoral land use system and appears to be the most viable for nebkha-dune stabilization in the eastern part of North Horr settlement
Sustainability of dryland agroforestry systems in eastern Kenya: farmers' perceptions, Physio-ecological factors and landscape patterns
(2011-12-19) Anyango, Stephen Obiero
The study focused on gaining an understanding of current farmers' practices and perceptions of locally evolving agroforestry trends and practices involving Grevillea robusta and Melia volkensi and their social and environmental relevance in dryland areas, in the eastern province of Kenya (Mbeere District). Pruning of tree roots as a technique for managing competition between trees and associated maize (Zea mays L.) crops for below-ground resources (water and nutrients) at the farm level was examined by comparing water use and nutrient accumulation by the trees and crop performance in root-pruned and unpruned hedgerow systems with equivalent sole crop control treatments during the 2000 short rainy season and 2002/03 long and short rainy seasons. Landsat satellite images for the years 1988 and 2000 were used to assess the impact of such agroforestry practices on vegetation cover at the landscape scale. The results show that subjective opinions provided by previous farming experience, association with other farmers, and the ease of propagating and establishing trees were the most important factors in promoting the adoption of Grevillea robusta by farmers. Conversely, the difficulty of establishing Melia volkensii was a major factor limiting its adoption. Root pruning of trees reduced the growth of Grevillea, and trunk basal diameter, diameter at breast height, canopy width and tree height were all lower in root-pruned than in unpruned trees (p<0.001). Maize grain yields were reduced relative to sole crops in systems containing unpruned trees, but were increased by root-pruning (p<0.004). Although root pruning generally reduced transpiration, factors such as soil characteristics and tree species were important. Exclusion of tree roots from the cropping area did not improve short-term supplies of soil organic N and P to meet crop requirements, as no significant differences in %N or extractable P concentrations were found between rootpruned and unpruned treatments for any of the species examined. However, soil moisture content adjacent to root-pruned trees was greater than in the equivalent unpruned treatment for all species (p<0.001). Trend analyses performed using data series generated from the years 1988 and 2000 Landsat images using the Normalised Vegetation Difference Index (NDVI) showed that notable changes in vegetation cover occurred during this period. Further analysis revealed an association between the observed NDVI trends, rainfall distribution and land use/land cover type within the study area. It was concluded that tree species with limited perceived and practical value are of little interest to resource-limited farmers, irrespective of the extent of their complimentarity with understorey crops or environmental value. Root pruning of trees improves access to available soil water for associated crops by enforcing niche differentiation, but may also reduce tree growth rate. Moreover, cumulative removal of nutrients such as nitrogen and phosphorus from the system over a period of years cannot be avoided or ameliorated by root pruning. The current agroforestry-based human-induced type of land cover may be associated with increased biomass of vegetation compared to unmanaged natural land cover types within the study area.

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