PHD-Department of Environmental Science

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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
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.
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.
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
A comparative study of the influence of variations in environmental factors on phytoplankton roperties of selected reservoirs in Central Kenya.
(2011-08-03) Kitur, Lesan Esther; Kotut, Kiplagat; Kerich, Richard Kimutai
Limnological information on reservoirs is important as it forms a vital baseline for among others the detection of undesirable changes in water quality. The physicochemical and phytoplankton properties were investigated in uhuru, Ruiru, Ngewa, Comte and Kianjjibbe reservoirs in central and Nairobi provinces of Kenya, over a period of 12 months (between February 2002 and January 2003) The aim of the study was to determine the nature and level of variation in the physico-chemical properties and its influence on phytoplankton composition, diversity and biomass. Sampling was done during day time and samples analyzed within four hours of sample collection. Among the limnological properties measured were: Secchi depth, temperature, electrical conductivity, dissolved oxygen pH, total alkalinity, nitrite-nitrogen, nitratenitrogen, total nitrogen, ortho-phosphate, total phosphate, soIuble reactive silica, phytoplankton composition and phytoplankton biomass. The study revealed varied degrees of seasonal changes in physico-chemical and phytoplankton properties of the reservoirs. Mean Secchi depth (SD) ranged from 0.1± 0.4 (Ndewa) to 0.9 ± 0.43 m (Ruiru). In general, the highest variation was noted during the dry season. Mean EC ranged from 45.8 ± 5.7 uS cm-1 (Ruiru) to 298.9 ± 41.5 pS cm- in Kianjjibbe with the highest EC being recorded during the dry season. Mean total alkalinity (TA) at the reservoirs ranged from 18.0 ± 0.24 mg L-1(Ruiru) to 110.2 ± 15 ') mg L-1 (Kianjjibbe). Mean nitrate nitrogen (N03-N) concentration ranged from 4.2 ± 043 pg L-' in (Ngewa) to 13.6 ± 1.14 pg L_1 in (Kianjjibbe). Low mean N03-N concciltration was recorded during the dry season. Mean total nitrogen (TN) concentration a the reservoirs ranged from 32.5 ± 28.7 Itg L-1 (Kianjjibbe) to 40.5 ± 36.9 lag L- (Comte). High (TN) concentration was recorded during the wet season. Mean total phosphorous (TP) ranged from 0.70 ± 0.25 pg L-1 (Kianjjibbe) to 1.03 ± 0.82 ug L-1 (Comte). High mean TP concentration was recorded during the wet season. Mean soluble reactive silica (SRS) concentration ranged from 3.2 f 0.47 (Uhuru) to 7.3 f 0.74 pg I ,(Ngewa). High SRS concentration was recorded during the dry season. A significant difference in Secchi depth electrical conductivity, total alkalinity, nitrate nitrogen total nitrogen, total phosphorus and Soluble reactive silica was noted in all the five reservoirs (P<0.001). A total of 35 phytoplankton genera belonging to 7 divisions were 1ccntified in all the five reservoirs. However the largest number of genera (16) belongs d to the Chlorophyta while Cryptophyta had only one genus. Total biomass ranged "rom 3291.87 mg L_1 (Ngewa) to 22,338.763 mg L-1 (Kianjjibbe). Most of the biomass vas due to Dinophyta. Wet season was characterized by high biomass. Total biomass between the reservoirs were significantly different (p<0.001). Phytoplankton biodiversity was high during the dry season. Uhuru reservoir had the highest diversity of 2.4 bits The study concludes that the reservoirs investigated vary in levels of physico-chemi,- 11 and phytoplankton properties investigated. This variation was attributed to differences in rainfall, volume of outflow and use dynamics of the water of the reservoirs.
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.
Determination of factors influencing the efficiency of legume green manures for maize production in Embu, Kenya
(2011-11-01) Gitari, Josiah Njiru
Land productivity in the central highlands of Kenya is mainly constrained by low and declining soil fertility. In the maize-based farming systems, continuous cultivation without adequate soil fertility enhancement measures has led to a deterioration of land quality resulting in low agricultural yields and degraded soils. Herbaceous legumes can provide an alternative to commercial fertilizers and animal manures. This study explored the use of these legumes in Embu District - situated within the central highlands of Kenya. In order to achieve this objective a survey and four field experiments were conducted to: (1) Validate farmers' knowledge and practices in soil fertility and use of plant residues; (2) Determine the performance of maize and green manure herbaceous legumes under different intercropping densities and relay-cropping regimes; (3) Investigate the relative efficiency of different legume residue management techniques and determine the need for mineral nitrogen (N) supplementation and (4) Determine the role of low quality plant residues as agents for slowing down the fast-decomposing legume residues to improve N synchrony for maize growth. The study consisted of one survey and four on-station field experiments. The survey involved a total of 134 small-scale farmers cutting across 5 major agro-ecological zones of the 30 km transect of the district. About 87 per cent of all the farmers in the district were affected by the problems of low soil fertility in their farms. Farmers gave soil colour and structure as some of the visual soil fertility assessment indicators used to determine soil fertility status in their farms but the most pronounced and elaborate local indicators seemed to be the dominance of certain weed flora. Soil pH and exchangeable bases (Ca++ and Mg++) were the most sensitive laboratory soil parameters that corroborated farmers' perceptions and knowledge of soil fertility. Results of the field experiments showed that it is feasible to intercrop maize with any of the three green manure legume species, namely, mucuna [Mucuna pruriens (L.) DC. Var. utilis (Wright) Bruck], crotalaria [Crotalaria ochroleuca G. Don] and lablab [Lablab purpureus (L) Sweet cv. Rongai]. Relay-cropping these green manure legumes (GML) beyond the second week after maize emergence had a significant reduction on legume biomass production possibly due to reduced photosynthetically active radiation (PAR) under the maize canopy. Intercropped GML intercepted less than 30 per cent of the total incident radiation. Nonetheless, intercropping of maize and GML greatly improved land productivity giving relative yield total (RYT) values of between 1.0 and 1.5. Incorporation or surface mulching of the GML residues gave similar maize yield responses that was about double that of the control (no residues). Supplementation of the GML residues (raised in situ) with mineral N was only beneficial if the quantities incorporated were below 2.0 Mg ha 1. Maize grain yield after mucuna, crotalaria and lablab residues alone (no mineral N supplemented) was 2.5, 2.3 and 1.6 times higher, respectively, than those of the control. Soil N mineralization reached a peak 4 weeks after planting (WAP) and declined thereafter until 8 WAP before picking up again for the remainder of the season. Seasonal mineral N levels ranged between 40 to 128 kg N ha 1. GML residue treated plots gave significantly higher total N uptake than the untreated plots. Over the 3 year period, legume residue incorporation resulted in a slight reduction (0.9-1.8%) in soil bulk density, a small increase in the soil total N but no change in the soil pH. Addition of low quality residues (maize stover) to any of the three GML residues did not affect N release but appeared to enhance their performance. Soil mineralization and maize N uptake was not affected by the addition of low quality residues to the GML residues but resulted in a small increase in the total soil N and pH. However, addition of large quantities of these low quality residues (6.0 Mg ha 1) significantly increased the soil organic carbon by 13 per cent and also decreased the soil bulk density by 8.3 per cent when compared to the absolute control with no residues added.
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.
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.
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
Environmental determinants of material morbidity and mortality in Bondo district, Kenya
(2011-08-10) Okumbe, Mukolwe Gaudencia
The evident disparities in maternal morbidity and mortality between developed and developing countries are of concern. These stem from the fact that developed countries have achieved very low rates of 9 maternal deaths per 100,000 live births, while developing countries have very high rates of 900 maternal deaths per 100,000 live births. In the developing world, 533,000 women lose their lives as a result of complications of pregnancy and delivery, unlike the developed world where there are only 6,000 deaths. The persistence of high maternal mortality ratios in developing countries despite the Safe Motherhood Initiative and efforts by the Inter Agency Group has led to prioritisation of maternal mortality reduction one of the UN's Millennium Development Goals. In Kenya, the maternal mortality ratios between different regions have displayed similar disparities with some regions in Central and Rift Valley Provinces having very low rates while some regions in the Coast, Western and Nyanza Provinces have very high rates, hence the problem of the study. The choice of Bondo District was based on the fact that the District is in one of the regions with a high maternal mortality rate of 620 deaths per 100,000 live births and a high number of health problems. The main objectives of the study were to estimate the maternal morbidity and mortality rates for Bondo District; determine environmental factors that impact on maternal morbidity and mortality; ascertain the extent to which each of these factors impacts on these phenomena in the District; and to assess progress made towards lowering maternal mortality rate in the District. The literature review covered several issues perceived to impact on maternal morbidity and mortality. The perspectives were founded on population theories, such as the demographic transition theory. This was followed by a review of maternal morbidity and mortality studies conducted worldwide. The Mosley and Chen's conceptual model (1984) of factors affecting mortality was adapted for this study. The methodology addressed the study site, the study design, methods of data analysis and their limitations. The study was conducted in five divisions of the District. A random sample of 50 enumeration areas was drawn from a total of 686 enumeration areas in the District. From each of the enumeration areas, 20 households were systematically sampled in proportion to the size of each enumeration area. From each household, a female of reproductive age 15-49 was selected for interview. A total of 1,000 female respondents were thus selected. Descriptive statistics and logistic regression analysis were applied in data analysis, using the statistical package for social sciences (SPSS). Common morbidities were malaria, during pregnancy and fever n postpartum period, while the least illness suffered was sexually transmitted disease (STD). The maternal mortality rate for the District was estimated at 477 deaths per 100,000 live births. The logistic regression analysis showed that environmental factors such as demographic attributes of age, socio-economic attributes of occupation, income and health attributes of family planning increased risks of maternal morbidity. The study confirmed increased risk of haemorrhage during pregnancy among women aged 3539, increased risks of postpartum haemorrhage in the age group 25-29 and 30-34, but reduced risks of haemorrhage in pregnancy among low income Age was also found to be a risk in some maternal morbidity areas such as cough, anaemia, and fever. The study recommends mandatory delivery in health facilities and attendance of postpartum care. It also recommends empowerment of women economically and educationally as a means to better healthcare. The study emphasizes the need for further study on causes of postpartum haemorrhage in adolescents and the link between the injectable and Norplant methods of contraception and anaemia
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.
Exploring nitrogen replenishment option for improving soil productivity in sites with varied soil fertility status in the central highlands of Kenya
(2011-11-01) Mucheru-Muna, M.
Declining land productivity is a major problem facing smallholder farmers in central Kenya. This decline is caused by low soil fertility caused by continuous cultivation without adequate addition of external nutrients. Two experiments were established during the 2004 short rains in two distinct agro-ecological areas (Mucwa and Mukuuni - sub humid & Machang'a - semi arid) in the central highlands of Kenya with an aim of enhancing soil productivity. The 1St experiment evaluated biomass transfer systems in Machang'a and Mucwa (two sites, one with fertile soils and the other with less fertile soils). Effects of organic sources (tithonia, lantana, mucuna, calliandra and manure) and combinations with mineral N fertilizer on maize yield, soil chemical properties, economics returns, soil mineral N, N uptake and fertilizer N equivalencies were determined. The 2nd experiment was an intercrop established in Mukuuni and Machang'a to determine the contribution of legumes (bean, cowpea and groundnut), plant spacing (conventional and MBILI) and P fertilizer on overall productivity of the intercropping system. Data was subjected to ANOVA and means separated using LSD (P < 0.05). Sole manure, sole tithonia and sole calliandra generally recorded the highest maize grain yields in Machang'a, Mucwa poor and Mucwa good sites, respectively. Generally the maize grain yields were lower in the treatments with fertilizer alone compared to the treatments with organics across the three sites in the four seasons due to the poorly distributed rainfall. The maize grain yields were higher in the sole organics compared to the integrations (organic+mineral fertilizer) in Mucwa good and poor sites, however in Machang'a, the sole organic had higher yields during the short rain seasons while the integrations recorded higher yields during the long rain seasons. There was a general decline in soil chemical properties over the seasons, even with the seasonal input application in all sites. Manure was superior in terms of improving soil chemical properties, for instance, it recorded an increase in soil pH, magnesium, potassium, calcium and nitrogen in all sites. The economic returns in all sites were low, with negative net benefits, and benefit cost ratio (BCR), which were in most cases less than one. The bulk of mineral-N found in the soil was in the form of nitrate-N in all sites, however in Machang'a the amount of ammonium-N was relatively high due to the drier condition of the soils in that site. In seasons when rainfall was well distributed, the N uptake was relatively high with most of the mineral N being taken up during 0-12 weeks after planting (WAP). High fertilizer N equivalencies of manure, calliandra, tithonia and mucuna were reported in all sites, suggesting that the organics have beneficial roles other than the addition of soil N. In the intercrop experiment, neither legumes nor maize responded to P application in Mukuuni while legume yield was increased by an average of 40% and maize yields more than doubled with P application in Machang'a. In both sites, legume yields tended to be higher when planted at the conventional intercrop, irrespective of legume species or P application; though not consistently significant in all seasons. Maize yields were significantly higher with conventional spacing when intercropped with groundnut, while in MBILI spacing, highest yields were observed for maize intercropped with beans. Generally net benefits, BCR and return to labour were highest when P fertilizer was not applied in both the MBILI and conventional intercrops in Machang'a and Mukuuni. In Machang'a, there were no economic advantages of MBILI over the conventional intercrop, while in Mukuuni MBILI intercrop had more economic benefits than the conventional intercrop especially in the maize/bean intercrop. The N equivalencies were very low both in the MBILI and conventional intercrops, actually in most cases the N equivalencies were negative. The role of organics was well displayed in the study area, which is prone to poor distributed rainfall, therefore further research should be carried out to explore issues of soil moisture conservation.
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.
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.
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.
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.
Land use and its effect on biodiversity in the lake ol' Bolossat basin, Nyandarua, Kenya
(2011-08-03) Macharia, Geoffrey Mugo
There is need to address factors that endanger species' survival now than ever before in order to reverse or slow down the rate of loss of biological diversity. The main objective of this study was to assess the effect of land use on biodiversity in the Lake Ol' Bolossat basin with land cover, human activity, birds and water quality as indicators. Land use aspects evaluated included human population, activity on farms and livestock. Land cover prior to this study was estimated from satellite images selected to reflect a time series pattern spanning about thirty years from 1973 to year 2000 The images were analyzed and interpreted using GIS technology. Systematic random sampling was done on crop cover. Farmers selected at random were also interviewed through questionnaires on key social economic aspects. Birds were counted in stations following the line transect technique along the lake edge between fixed stations approximately 2 km apart. Water quality physical-chemical parameters were measured by means of a portable electronic meter. Water level was determined using temporary and permanent gauges. The common land use types found in the area were mainly subsistence arable farming and livestock rearing. Subsistence farming was the major land use with four crops maize (56%), potatoes (20%), beans (6%) and carrots (7%) having the largest land cover on farms. Increased human population which had a cumulative growth of over 316% from 176,928 in 1969 to approximately 559,626 in 1999 had caused intensification of land use and exploitation of land based resources. Rapid expansion of farms decreased and altered natural habitats of the riparian reserve and the forest. This resulted in acceleration of soil erosion and silt deposition. Population increased and exerted tremendous pressure on the natural ecosystem. Regression analysis of satellite land cover data and human population changes over the corresponding period revealed human population to be the principal factor in all cover area changes observed accounting for 87% on the coefficient of determination, (r2 ). This had reduced the area of the lake water mass while deposition of silt increased the area under marsh. Human activities had some influence on the occurrence and distribution of communities of birds and had variable effects on water quality parameters. Water dissolved oxygen recorded was between 0.60mg 1"1 and 9.60mg 1"1. pH value had a range between 6.5 and 9.6 while conductivity was between 172 and 465pS. Dissolved oxygen was influenced by all activities to some extent while the pH was not. Conductivity was affected by land preparation, weeding and harvesting. Water abstraction on the eastern side of Lake Ol' Bolossat influenced hydrologic processes and decreased inflow. Environmental degradation, notable as soil erosion, overgrazing, burning. and encroachment onto the riparian and forest reserves, were found at various areas of the basin. Environmental rehabilitation was minimal in the basin, particularly on the eastern side of the lake. This study, therefore, supports the conclusion that increasing exploitation of land, water and biological resources principally affected biodiversity in the Lake Ol' Bolossat ecosystem.

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