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Item Morphological Structure and the Anthropogenic Dynamics in the Lake Naivasha Drainage Basin and its Implications to Water Flows(Summer School 2005) Onywere, S. M.Throughout its length, the Kenyan Rift Valley is characterized by Quaternary volcanoes. At Lake Naivasha drainage basin, the Eburru (2830m) and Olkaria (2434m) volcanic complexes and Kipipiri (3349m), Il Kinangop (3906m) and Longonot (2777m) volcanoes mark the terrain. Remote sensing data and field survey were used to make morphostructural maps and to determine the structural control and the land use impacts on the drainage systems in the basin. Lake Naivasha is located at the southern part of the highest part of Kenya’s Rift Valley floor in a trough marked to the south and north by Quaternary normal faults and extensional fractures striking in a N18°W direction. The structure of the rift floor influences the axial geometry and the surface process. Simiyu and Keller (2001) interpret the rift floor structure as due to thickening related to the pre-rift crustal type and modification by magmatic processes. The rift marginal escarpments of Sattima and Mau form the main watershed areas. From the marginal escarpments the Rift Valley is formed by a series of down-stepped fault scraps. These influence the nature of the soils and the rainfall regime. The drainage is also influenced by the fault trends. At the Malewa fault line for example the drainage is south-easterly influenced by the trend of the Malewa fault line (Thompson and Dodson, 1963). The morphotectonic control on the drainage has implications on ground water recharge in the Naivasha basin. This may also influence the spring water supply and geothermal reservoirs. The nature of the terrain, human development processes and their impact on the lake was visualized using Landsat TM satellite data (path 169/Raw 060) from three dates (28/1/1986 L5, 1/3/1989 L4Item In-kind transfers of maize, commercialization and household consumption in Kenya(Journal of Eastern African Studies, 201) Wambugu, Stephen K.; Djurfeldt, A. A.This article discusses in-kind food transfers and whether such transfers should be interpreted as a sign of the failure of grain markets to meet the food demands of the poor. The article elucidates on aspects of both consumption and in-kind transfers of maize against a backdrop of poorly functioning markets. It adds to the theoretical understanding of household based linkages and provides a documentation of in-kind commodity flows missing in many discussions of such linkages. The purpose of the article is twofold: first, it sheds light on the phenomenon of in-kind transfers of staple crops in the Kenyan context; secondly, it assesses the wider reciprocal and livelihood implications for the transferring households. The article relies on three sets of data with respect to methodology. It uses quantitative data collected at the household level in 2008, qualitative data collected at the village level in 2002 and 2008, as well as qualitative household level data gathered through in-depth interviews with 30 heads of household and farm managers in Western Kenya in June and July 2006. The survey found that 38% of the households transferred maize to their relatives. The explanations for in-kind transfers are not primarily related to poor price incentives, but the functioning of household support systems across space. In-kind transfers therefore at times drain the food resources of sending households while constituting important sources of food security for receiving households. While the focus in the literature is generally on rural–urban linkages, the direction of maize transfers was primarily rural-to-rural. The article concludes that existence of food transfers underpins the necessity of improving commercial incentives for maize and other foodstuffs and eliminating physical barriers to free movement of foodstuffs across the national space.Item The Impact of Export Processing Zone Development on Employment Creation in Kenya(WILEY, 2002-12-19) Mireri, C.This paper examines the contribution of Export Processing Zones (EPZ) to employment creation in Kenya. The results suggest that employees in non-EPZ businesses are better paid than those in the EPZ. Firms in the EPZ employ more women than the Kenyan national average, although the proportion is less than the international average amongst EPZs. Against the general fear that EPZ enterprises offer little employment, the number of employees in the EPZ enterprises are comparable to those found outside as are working hours. A weak trade union movement, inefficient and inadequate social security, lack of employment benefits, lack of opportunities for training and promotion and low pay are problems encountered by those working in an EPZItem Challenges Facing the Conservation of Lake Naivasha, Kenya(FWU Water Resources Publications, 2005) Mireri, C.This paper shows that sustainability of Lake Naivasha is threatened by the land use transformation in the watershed. Lake Naivasha is the only freshwater lake in the Kenyan Rift Valley. The basin extends 60 North from the equator and lies between 36007’ and 36047’ east of Greenwich Meridian. It is a shallow lake located at an altitude of about 1885m above sea level. Its watershed measures approximately 3400km2. The population in the area surrounding the lake has rapidly grown from 43,867 in 1969 to the current figure of about 250,000. The lake is located in a semi-arid environment and it is drained by only two perennial rivers - Malewaand Gilgil. Lake Naivasha area plays a very important role in national development. The area contributes to about 70% of Kenyan flower export, 15% of Kenyan electric power and is home to attractive tourist sites. Since independence in 1963 the area has witnessed rapid land use transformation from commercial ranching to a mixture of commercial ranching and rapidly growing smallholder (rural and urban) settlements. As a result the area has witnessed a high increase in demand for the hitherto scarce environmental resources and services (for example water, sanitation and forestry) leading to unsustainable utilisation of the lake. Although water is abstracted from both, the lake and underground sources, there is no metering. Sustainable management initiatives of the lake should focus on: institutional framework and human resources; monitoring of the abstraction of water resources; waste management, physical infrastructure; soil and forestry conservation and farming technologies.Item Effect of Water Hyacinth Infestation on the Physicochemical Characteristics of Lake Naivasha(2005) Onywere, S. M.; Mathooko, J.M.; Mironga, J.M.Water hyacinth (Eichhornia crassipes) is an invasive aquatic macrophyte associated with major negative economic and ecological impacts in the Lake Naivasha region since the plant’s introduction into the lake in 1986. The study hypothesized that water hyacinth had significantly affected water quality of Lake Naivasha. Field measurements were done to determine the impact of water hyacinth on water quality. Two sampling sites were selected (one under water hyacinth and another at shore line without water hyacinth) to compare the results of the measurements. At each of these habitats 10 sampling areas were randomly selected. Water quality variables from the two habitats were compared by means of one-way analysis of variance (ANOVA). The sample analysis showed that free carbon dioxide was significantly higher (P<0.05) in water hyacinth infested areas (26.45±1.02 mgL-1) than in open water (12.86±1.92 mgL-1). Dissolved oxygen was significantly lower (P<0.05) in the infested areas (1.96±0.71 mgL-1) when compared with open water (5.98±0.85 mgL-1). Similarly pH was significantly lower (P<0.05) in water hyacinth infested area (6.92±0.04) than in open water (7.71±0.05). Although the temperature was higher in the infested areas (27.5±0.600C) than open water (26.7±0.520C) the difference was not significant (P>0.05). It can therefore be concluded that the presence of water hyacinth was found to have affected the ecology of Lake Naivasha and therefore it’s utility. Effective control of water hyacinth in Lake Naivasha is important, in order to prevent both ecological and economic loss due to loss of biodiversity.Item Urban Agriculture in East Africa: practice, challenges and opportunities(City Farmer, 2006-03-20) Mireri, C.; Kyessi, A.; Mushi, N.; Atekyereza, P.This paper attempts to put into perspective urban agriculture in East Africa. The main themes of the paper are: definition of urban agriculture; characteristics of urban agriculture; role of urban agriculture in employment, income, and food supply; policy and institutional framework for urban agriculture; and urban agriculture and environment. The paper demonstrates that urban agriculture is an important feature of the urban land use system. Since the colonial era, urban agriculture remains outside the urban land use system. Therefore, the sector does not enjoy the much needed institutional support. Although Tanzania has integrated urban agriculture in the urban land use system, it remains officially excluded from Kenyan urban land use system. Despite the fact that it is not integrated into the urban land use system, it is an important feature of the urban economy. It is evident that urban agriculture makes important contribution to employment, income and food supply. It is an important source of income and food supply for the commercial and poor urban farmers respectively. Due to environmental degradation and heighten poverty, there are health risks associated with urban agriculture in hazardous areas or use of unsafe water. The urban economies can greatly benefit from urban agriculture, if all the governments of East Africa can develop a policy and institutional framework on the sector. This would ensure enhanced agricultural productivity and safety of the produce.Item Reconsidering Urban Sewer and Treatment Facilities in East Africa as Interplay of Flows, Networks and Spaces(Springerlink, 2009) Sammy, Letema; Bas van, Vliet; Jules B., van LierUrbanization has brought about concentrations of people in densely populated settlements, resulting in the generation of waste water that needs to be disposed off in a hygienic way to avoid the outbreak of diseases. Decisions on what area to sewer, the nature of sewer schemes and treatment works to be used, and the kind of collection and transport system to adopt is often complex and difficult to make. This chapter (re)considers urban sewers and treatment works as the interplay of flows, networks and spaces, and puts forward a conceptual framework for decision-making. It examines current and future sanitation structures in Kampala and Kisumu in terms of sanitation flows, sanitary networks and demands for space. Knowledge of such sanitation structures serves as an input to the assessment of opportunities for so-called Modernized Mixtures of sanitation systems in cities around Lake Victoria.Item Community and Social Responses to Land Use Transformations in the Nairobi Rural-Urban Fringe, Kenya(2010) Thuo, A.D.M.The process of urbanization is one of the most important dimensions of economic, social and physical changes. It is almost a truism that the planet’s future is an urban one and that the largest and fastest growing cities are in developing countries. Approximately 25 percent of Africa’s population lived in towns and cities in 1975. By the year 2000, due to rural-urban migration and rapid rates of natural increase, 38 percent of the continent’s population lived in urban areas. The proportion is expected to increase to 47 percent by 2015 and to double by 2025, Kenya is not an exception. Rapid urban population growth means an increasing demand for urban land. This land is not available within the city, but in the rural-urban fringe, for various reasons. This is partly due to low land prices, high rents at the core of the cities and legal flexibility in land use planning in the rural-urban fringe. Urban growth is already engulfing the surrounding agricultural lands and small villages. The conversion of agricultural land to residential uses is leading to the rapid transformations in the agricultural production, spatial structure, social structure, land ownership and land market in these areas. This chapter focuses on the responses/actions of the communities within Nairobi rural-urban fringe and how they manoeuvre through the consequences of changes occasioned by land conversions. It used Town council of Karuri as a case study. The chapter is based on qualitative research approaches presents evidence on how subaltern’ actions plays an important role in creating order in an otherwise chaotic situation as a result of ‘poorly planned’ residential development. The subalterns’ actions, as evidenced by their agency, are manifested in community’s contribution and participation in provision of infrastructure and services within the Nairobi’s rural-urban fringe due to inability of formal provision by planning authorities.Item Participatory Natural Resource Management - Policy and Institutional Framework- (Part 1)(IOS Press, 2011) Mireri, C.; Calestus, O.; Museng'ya, M.P.Item Assessing the Challenge of Settlement in Budalangi and Yala Swamp Area in Western Kenya Using Landsat Satellite Imagery(Bentham Science, 2011) Onywere, S. M.; Getenga, Zachary M.; Mwakalila, Shadrack S.; Twesigye, Charles K.; Nakiranda, Josephine K.The Budalangi area of Kenya exhibits high levels of rural poverty despite its natural resources potential and favourable climate. The area was mapped using multi-temporal remote sensing image data from 1973 to 2009 and participatory data collection. Floods are a recurrent environmental hazard and impede access to environmental resources and agricultural production. The physical setting of Budalangi at the floodplain of Nzoia River and increased runoff from degraded catchments are contributory factors to the flooding. Floods lead to disruption of human settlements and destruction of crops, shelter, dykes and infrastructural facilities. Disease outbreaks also increase due to destruction of sanitation facilities and relocation of settlements in makeshift camps. This implies that the policy measures that have been instituted by the government to mitigate the problem have had dismal impact in the Budalangi and Yala Swamp area. The degradation of the catchment is reflected in its sediment loading and deposition into Lake Victoria which has seen the morphology of the coastline at the mouth of Nzoia River and the aerial coverage by water in the lake change over the years. The overall loss in the area under Yala Swamp is 54 Km from 186 Km in 1973 to 132 Km in 2009. The encroachment has significant implication on the wellbeing of the Yala Swamp and the Nzoia Floodplain ecosystem. The study therefore underscores the need to evolve an integrated watershed management plan for effective management of Budalangi and Yala Swamp area and the region in general.Item The Impact of Land Use Activities on Vegetation Cover and Water Quality in the Lake Victoria Watershed(Bentham Open, 2011) Twesigye, Charles K.; Onywere, S. M.; Getenga, Zachary M.; Mwakalila, Shadrach S.; Nakiranda, Josephine K.The impact of land use activities on loss of vegetation cover and water quality was assessed in three selected sites within the Lake Victoria Basin using remote sensing technologies and standard water quality analysis techniques. The three study sites were: (i) Nzoia River Basin (Kenya), (ii) Nakivubo Wetland (Uganda) and (iii) Simiyu drainage basin (Tanzania). Lake Victoria is the second largest fresh water lake in the world and is served by a drainage basin area of over 193,000 km2, traversing five East African Community States; Kenya, Uganda, Tanzania, Rwanda and Burundi. This paper examines the impact of land use activities on vegetation cover and water quality based on remote sensing and Geographical Information Systems analysis combined with chemical and physical water analysis. The quality of the effluent generated by the industries found within the study sites and their effects on downstream discharge was also determined. Pesticide residues in soil and water samples were determined using analytical standard methods. Soils from some selected fields in Nzoia River basin showed high levels of compounds such as aldrin, dieldrin, endosulfan, DDT, and endrin which are together referred to as persistent organic pollutants (POPs). The physical and chemical analysis of water quality revealed high levels of phosphates and nitrates along the agricultural zones of River Nzoia Basin. The satellite images revealed that in all the three study sites land vegetation cover has continuously reduced in size. The extent of environmental degradation caused by agricultural, domestic and industrial wastes and how this affects loss of vegetation cover and water quality is discussed.Item The Effect of Water Hyacinth (Eichhornia Crassipes) Infestation on Phytoplankton Productivity in Lake Naivasha and the Status of Control(David Publishing, 2011) Onywere, S. M.; Mironga, J.M.; Mathooko, J.M.The paper presents data collected in an assessment of the effects of water hyacinth (Eichhornia crassipes) infestation on phytoplankton productivity in Lake Naivasha. A summary of the status of control and strategies used is given. The ecological effects of water hyacinth on the lake have received little attention compared to the large body of work available on the weed’s socioeconomic impact. This study was conducted to determine the effect of hyacinth infestation on the phytoplankton productivity. Several sampling stations were set up in the lake at sites containing floating mats of the weed and at sites where the weed was absent. Phytoplankton chlorophyll-a concentration and dissolved oxygen were measured at each station and used as proxies for phytoplankton productivity. The findings show that phytoplankton productivity in weed covered areas is reduced with significant change in species composition and biodiversity suggesting that water hyacinth can alter the ecology of the lake. Although water hyacinth has continued posing serious ecological consequences, the control strategies already adopted will continue to reduce deleterious impacts and allow sustained development in the Lake Naivasha Basin. There is need however to undertake research to quantify the level of ecological damage and the costs of control. There are other effects such as livelihood loss, diseases, and disruption of normal operations that also need to be quantified.Item Participatory Natural Resource Management- Policy and Institutional Framework - (Part II)(IOS Press, 2011) Mireri, C.; Calestus, O.; Museng'ya, M.P.Item Public open spaces in Nairobi City, Kenya, under threat(Journal of Environmental Planning and Management, 2011-10) Mireri, C.; Makworo, M.The paper demonstrates that public open spaces in Nairobi City have been increasingly threatened by congestion and deterioration as result of the rapid rate of urbanisation (5–7.5%), poor planning, weak management and illegal alienation. According to the 1948 Master Plan for the city, city planning was premised on the neighbourhood concept with ample provision of public open spaces. However, after Kenya’s independence in 1963, the implementation of the Master Plan was largely abandoned. Rapid and uncontrolled urbanisation meant that public open spaces that were intended to serve a population of 250,000 now serve over 3 million people. Public open spaces in the city suffer from degradation, overcrowding and insecurity, thus denying city residents access to the much-needed recreation and leisure facilities. Keywords: public; parks; spaces; Nairobi; KenyaItem Satellite Sanitary Systems in Kampala, Uganda(Mary Anne Liebert, 2012) Letema, Sammy; Bas, van Vliet; Jules, B.Satellite sewage collection and treatment systems have been independently developed and managed in East African cities outside the centrally planned and sewered areas. A satellite approach is a promising provisioning option parallel to public sewerage for middle- and high-income residential areas, endowed institutions, and government facilities. Although the studied satellite systems offer localized solutions that fit the situation of Kampala, better treatment and management arrangements are needed. Such arrangements do not readily conform to centralized or decentralized sanitation paradigms and likely require flexible mixtures of the two into modernized mixtures. In the case of Kampala, such mixtures entail regulation and control by centralized agencies, development and management by decentralized satellite providers, hybrid treatment process, and separation of waste (water) flows.Item Use of Remote Sensing Data in Evaluating the Extent of Anthropogenic Activities and their Impact on Lake Naivasha, Kenya(2012-02-22) Onywere, S. M.This study investigated the anthropogenic activities in Lake Naivasha Basin and how they are influencing the quality of water resources. The poor quality of water in the lake is seen from the presence of water hyacinth (Eichhornia crassipes) and is a reflection of nutrient rich waters. The water hyacinth in Lake Naivasha is associated with major negative economic and ecological impacts. The intensity of land use within the basin was mapped from multispectral Landsat satellite imagery of 1986 (TM) and 2000 (ETM) and SPOT imagery 10 m (resolution) of 2007. From interpreted data, the surface area of the Main Lake has decreased from 134.9 km in 1986 to 117.5 km in 2007 (12.9%); that of papyrus and wetland grasslands along the lake shore decreased from 54.6 km to 34.3 km (37.2%) and that of the horticultural and irrigated farms increased by 103.3% from 45.1 km to 91.7 km in the same period, placing great pressure on both the quality and quantity of the lake’s water resources. Information obtained from the Fisheries Department in Lake Naivasha show that the fishery production declined from 513 to 110 tons in the period considered. The Naivasha Municipal Council records indicate a 30% decline in the water it supplies to Naivasha Town from 10,000 m3 to 7,000 m3 in the same period despite the increase in population. The decline was attributed to many factors among them the presence of water hyacinth and the decline in water quantity due to increased human activities.Item Environmental Planning and Management(2012-02-22) Onywere, S. M.This study investigated the anthropogenic activities in Lake Naivasha Basin and how they are influencing the quality of water resources. The poor quality of water in the lake is seen from the presence of water hyacinth (Eichhornia crassipes) and is a reflection of nutrient rich waters. The water hyacinth in Lake Naivasha is associated with major negative economic and ecological impacts. The intensity of land use within the basin was mapped from multispectral Landsat satellite imagery of 1986 (TM) and 2000 (ETM) and SPOT imagery 10 m (resolution) of 2007. From interpreted data, the surface area of the Main Lake has decreased from 134.9 km in 1986 to 117.5 km in 2007 (12.9%); that of papyrus and wetland grasslands along the lake shore decreased from 54.6 km to 34.3 km (37.2%) and that of the horticultural and irrigated farms increased by 103.3% from 45.1 km to 91.7 km in the same period, placing great pressure on both the quality and quantity of the lake’s water resources. Information obtained from the Fisheries Department in Lake Naivasha show that the fishery production declined from 513 to 110 tons in the period considered. The Naivasha Municipal Council records indicate a 30% decline in the water it supplies to Naivasha Town from 10,000 m3 to 7,000 m3 in the same period despite the increase in population. The decline was attributed to many factors among them the presence of water hyacinth and the decline in water quantity due to increased human activities.Item Partnership for Research on Viable Infrastructure Development in East Africa(2012-03-15) Majale, Christine LiyalaItem Effect of Water Hyacinth Infestation on the Physicochemical Characteristics of Lake Naivasha(2012-04) Mironga, John Momanyi; Mathooko, Jude M.; Onywere, S. M.Water hyacinth (Eichhornia crassipes) is an invasive aquatic macrophyte associated with major negative economic and ecological impacts in the Lake Naivasha region since the plant’s introduction into the lake in 1986. The study hypothesized that water hyacinth had significantly affected water quality of Lake Naivasha. Field measurements were done to determine the impact of water hyacinth on water quality. Two sampling sites were selected (one under water hyacinth and another at shore line without water hyacinth) to compare the results of the measurements. At each of these habitats 10 sampling areas were randomly selected. Water quality variables from the two habitats were compared by means of one-way analysis of variance (ANOVA). The sample analysis showed that free carbon dioxide was significantly higher (P<0.05) in water hyacinth infested areas (26.45±1.02 mgL-1) than in open water (12.86±1.92 mgL-1). Dissolved oxygen was significantly lower (P<0.05) in the infested areas (1.96±0.71 mgL-1) when compared with open water (5.98±0.85 mgL-1). Similarly pH was significantly lower (P<0.05) in water hyacinth infested area (6.92±0.04) than in open water (7.71±0.05). Although the temperature was higher in the infested areas (27.5±0.600C) than open water (26.7±0.520C) the difference was not significant (P>0.05). It can therefore be concluded that the presence of water hyacinth was found to have affected the ecology of Lake Naivasha and therefore it’s utility. Effective control of water hyacinth in Lake Naivasha is important, in order to prevent both ecological and economic loss due to loss of biodiversity.