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Item Estimation of Aboveground and Belowground Carbon Sequestration of Cupressus Lusitanica, Pinus Patula and Eucalyptus Saligna Plantation Species in Kenya(United Nations Conference Centre, 2016) Oeba, Vincent Onguso; Otor, S.C.J.; Samuel, Kung’u B.; Shisanya, C.A.Item Seasonal rainfall variability and aptness of Geographical-Information- Systems (GIS) interpolation techniques in the arid regions of Embu county, Kenya(African Crop Science Society, 2013) Kisaka, O.; Mucheru-Muna, M.; Ngetich, F. K.; Mugwe, J.; Mugendi, D.; Mairura, F.This study sought to characterize inter/intra seasonal rainfall variability, drought probabilities and assess the efficacy of geo-statistical interpolation techniques for spatio-temporal reconstruction of rainfall data in arid areas of Embu County; Kenya. Gaps in rainfall data from two stations of Embu and Machang’a were filled using multiple imputations. Cumulative Departure Index (CDI), Rainfall Anomaly Index (RAI) and Coefficients-of-Variance (CV) and probabilistic statistics were utilized in the analyses. Data reconstruction utilized ArcGIS environmental tool combined with the digital elevation model (DEM) to generate average spatial rainfall and maps using various interpolation techniques. The efficacy of interpolation techniques was assessed using root mean square errors (RMSE), mean absolute errors (MAE) statistics plus gauged-data for validation. Rainfall homogeneity was accepted at 99% probabilities. Probabilities of rainfall exceeding cropping threshold were 50% (506.8mm) at Embu and 30% (523.7mm) at Machang’a during Long-Rains (LRs) and Short-Rains (SRs) respectively. High variability was observed in rainfall amounts (CV=0.41 and 0.36) during LRs and (CV=0.56 and 0.38) during SRs in Machang’a and Embu respectively. Daily rainfall distribution depths were highly skewed; small proportion of rainy days supplying a high proportion of rainfall. Variabilities in rainy days were CV=0.26 and 0.08 (LRs) and CV=0.88 and 0.27 (SRs) in respective stations above. High variability were observably in March (onset) (CV=0.98 and 0.61) and October (onset) (CV=0.80 and 0.66) respectively. Dry-spell probabilities within growing months were high (81%) and (60%) in Machang’a and Embu respectively. Kriging technique was identified as the most appropriate Geo-statistical and deterministic interpolation techniques that can be used in the region. To optimize yield in the area, use of soil-water conservation and supplementary irrigation, crop selection and timely accurate rainfall forecasting should be prioritized. Key words: Cumulative-Departure-Index, GIS, Interpolation, Kriging, Rainfall-Anomaly-Index, Rainfall-variabilityItem Adapting conservation agriculture to climate change variability: An overview of sorghum and cowpea production in Kirinyaga west county(African Crop Science Society, 2013) Njeru, P. N. M.; Maina, I.; Mugwe, J.; Mucheru-Muna, M.; Mugendi, D.; Lekasi, J. K.; Kimani, S. K.; Miriti, J.; Mugo, B. J.; Mwangi, H.; Oeba, V. O.; Muriithi, F.Rain-fed agricultural productivity has continually declined due to unpredictable and unreliable rainfall patterns in Kirinyaga West County. The decline in food productivity has been as a result of inadequate understanding of intra-seasonal rainfall variability to develop optimal cropping calendar. A study was conducted to access the effect of various water harvesting and integrated soil fertility management technologies for enhanced sorghum (Sorghum bicolor (L.) Moench) and cowpea (Vigna unguiculata L.) productivity in Kirinyaga West County, Central Kenya. The field experiment was laid out in Partially Balanced Incomplete Block Design (PBIBD) with a total of 36 treatments replicated three times. The treatments of tied ridges and contour furrows under sorghum alone plus external soil amendment of 40 Kg P /ha + 20 Kg N /ha + manure 2.5 t/ha had the highest grain yield ranging from 3.3 t/ha to 3.6t/ha. The soil fertility levels differed significantly from one another (p=0.0001) in terms of sorghum grain yield. Generally, all experiment controls had the lowest grain yields as low as 0.4 t/ha to 0.6 t/ha. Therefore, integration of minimal organic and inorganic inputs under various water harvesting technologies could be considered as an alternative option towards food security as a way of climate change mitigation options for Kirinyaga West County in Central Kenya. Key words: Climate change, food security, soil amendmentsItem Urban planning and sprawl crisis in Africa: ecological sanitation as a viable policy option(2003) Ndung'u, Abraham G.Rapid urban growth is a common phenomenon the world over,particularly in the developing countries. Africa is no exception in this respect. Lack of affordable housing in African towns has pushed most people into the peri-urban areas. These new settlement areas, often hitherto agricultural lands, are normally unplanned. "Development", therefore, seems toprogress ahead of planners instead of the other way round. By implication, therefore, these periurban areas often lack vital services necessary for human settlement such as proper sanitation, particularly human excreta disposal. In these areas the most affordable and therefore most common method of human excreta disposal is the use of pit latrines. In few homes, however, isolated cases of use of cesspits and septic tanks can befound. In comparison with conventional methods of human excreta disposal, ecological sanitation (eco-san) is a viable and feasible alternative in these peri-urban areas since it has a lot of advantages, viz.: recovery and re-use of nutrients for urban agriculture; minimal risk from spread of diseases; cost-effectiveness; minimal/no use of water and no contamination of ground water. As such adoption of eco-san is the likely way forward for planning for sanitation services in Africa s peri-urban areasItem Health facility utilization differentials: a case of Mathare and Soweto slums, Nairobi(Kenyatta Universiry, 2003) Keraka, Margaret N.; Oyieko, ErnestEvidence from studies carried out by KDHS (1998), UNCHS (1996), Hardoy (1990), Republic of Kenya (1988), UNICEF and WHO 1984 and AMREF (1989) indicate high levels of child mortality in Nairobi. This has been attributed to disparities in availability and utilization of health care facilities and services. This paper, therefore, aims at examining the extent of provision and utilization of health care services, factors affecting utilization and provision of health care facilities, impact ofthe existing disparities in the usage and provision of health on child morbidity, indigenous medical beliefs relating to common ailments, use of traditional and biomedical service. It also gives recommendation of how such disparities and their impact can be avoided. Primary data collected using in-depth interviews and focus group discussion was used. The respondents were mainly caretakers of children under five years and clinical officers from private and public hospitals. Secondary data was also obtained from the KDHS (1998) and thel999 Kenya population Census.The study established that there were fewer modem health care facilities and that the rate of utilization was low. This is evident from the fact that there were more disease incidences reported in study areas compared to those found in the 1999 population Census for Nairobi province.It was recommended that the government gives small loans to slum dwellers that can be used to start income generating activities. This will in turn assist them to participate effectively in the cost-sharing expenditure in medicine. In addition, that there should be increased awareness campaigns to recognize the importance of utilizing available health care facilities.Item Environmental impacts and disparities associated with rural urban migration(Kenyatta Universiry, 2003) Abwao, PeterPopulation change in a given area is an aspect of demographic study, which relates to biophysical and human phenomena Conceptually, it embraces the three components of population dynamics -fertility, mortality and migration- which influence both population structure and change. However, this paper places emphasis on migration, whichredistributes the population in both time and space, resulting inpopulation changes discernible through their impactson the environment. Migration is the movement of people across a specified boundary. It falls into two categoriesnamely international and internal. It is international when it occurs between countries and internal when withinthe same country such as the case of rural-urban migration. These broad forms of migration have far reachingconsequences on the environment both at the origin and destination. This paper addresses itself to ruralurbanmigration, its impact on the environment and resultant rural-urban disparitiesItem Disparities in wildlife resource governance and implications for environmental management in commercial and communal ranches of Laikipia District, Kenya(Kenyatta Universiry, 2003) Olukoye, Godfrey A.Laikipia rangelands of Kenya are endowed with diverse natural resources that support both livestock and wildlife enterprises. Laikipia district is, therefore, home to several commercial and communal ranches. However, disparities in wildlife resource governance in these two categories of ranches have serious implications for environmental management. Such disparities have led to the "perceived" mismanagement of resources in communal ranches with concomitant environmental degradation in, for example, Mukogodo pastoral rangelands. On the other hand, the commercial ranches have a "perceived" appropriate management system with environmental conservation and upgrading as its yardsticks. However, one question that still remains unanswered is whether the perceived mismanagement in communal ranches is the making of the Laikipia pastoralists. This paper sets out to answer this question and discusses the ecological and socio-economic causes of disparities in wildlife resource governance in communal and commercial ranches. It is concluded that a level playing field for the two categories of ranches coupled with local capacity building are essential ingredients towards a comprehensive wildlife resource governance and resource use conflict resolution in Laikipia Rangelands of Kenya.Item Marine resource and management- a case study of Kenyan coast(Kenyatta University, 2009) Gakai, P.K.; Njuguna, S.G.; Macharia, G.Item Effects of organic and inorganic fertilizers on soil total bacteria, denitrifying bacteria and fungal microbial communities in a long-term experiment, Kabete Kenya(Kenyatta University, 2009) Kamaa, M.M.; Kung'u, J.B.; Njagi, N.M.; Lesueur, D.Item Analysis of water use trade-offs between crop and livestock in Kalacha settlement, Marsabit district, Kenya.(Kenyatta University, 2009) Sikunyi, T.M.; Olukoye, G.A.; Koske, J.K.A.Item Cost-benefit analysis of farmer-tested soil fertility replenishment technologies in Kirege Location, Chuka Division, Eastern Kenya(The Soil Science Society of East Africa National Research Laboratories, 2005) Kangai, R.; Mugendi, D.N.; Kung'u, J.B.; Mucheru-Muna, M.; Otor, S.C.J.; Waswa, B. S.; Mugwe, J. N.A study was conducted in Chuka Division, eastern Kenya to assess trends in adoption of soil fertility replenishment strategies. Eighty farmers adopted the soil fertility improvement technologies during the short rains season of200 1.During the subsequent 2 seasons, 163 and 206 farmers representing an increase of 99% and 150% above the initial adopters practiced the soil fertility improvement strategies. Technologies involving use of Tithonia diversifolia and Calliandra calothrysus alone or in combination with inorganic fertilizer were readily adopted due to the high yields obtained as well as being sources of fodder. During the 151 season of farmer follow-up, tithonia + Y2 of inorganic fertilizer gave the highest net benefit ofKshs. 50133 ha' and was followed by the full rate inorganic fertilizer treatment with a net benefit of Kshs. 39568 ha'. Tithonia treatment had the highest benefit cost ratio (BCR) of 5.4. Sole manure treatment recorded the lowest net benefit (Kshs. 4601) and hence the lowest BCR of 0.9. However, during the 2nd season, manure plus Y2 rate of recommended inorganic fertilizer recorded the highest net benefit (Kshs. 41567) with a BCR of 3.7. Farmer practice involving no input had the lowest BCR of 0.2 with a net sale of Kshs. 9853. Sole tithonia treatment Traditional farming systems in Africa relied had the highest BCR (4.6) indicating greater on shifting cultivation practices to replenish benefit per unit investment. Constraints to soil fertility. According to Sanchez and the adoption of the proposed soil fertility Leakey (1997) and Vissoh et al. (1998), this 511 ABSTRACT improvement strategies were identified as inadequate labour, poor yield observed from some of the technologies at the demonstration trial, inadequate organic and inorganic resources and laxity due to fear offailure. The technologies were seen to increase food production at affordable cost at the same time improving the soil quality in the area. Therefore tackling of the mentioned limitations to adoption of soil fertility technologies need priority in any effort to encourage widespread adoption. Timing application of the organic resources needs to be ensured to check on conflicts between labour requirements with other farm or domestic choresItem The role of plant residues in soil productivity: farmers' knowledge and practices in Embu District, Kenya(The Soil Science Society of East Africa National Research Laboratories, 2005) Gitari, J. N.; Mugendi, D.N.; Mureithi, J. G.; Kung'u, J.B.; Gachene, C.K.K.Plantresidues from trees, crops or weeds playan important role in determining the soil fertilitystatus in smallholder farmers of the centralhighlands of Kenya region. A study wasconducted in Embu district of Kenya, locatedin the densely populated windward side of the south-eastern slopes of Mount Kenya,to document farmers knowledge and practices in the prevalence and utilisation ofthese residues. A total of 134 small-scale farmers cutting across five major agroecological zones of the 30 km transect were interviewed. Farmers indicated that trees, crops or weed residues found in their farms were associated with generation of plant residueswhicheitherimproveorimpoverish the farm niches where they are found. Plant residues that were associated with soil fertility enhancement included: Zea mays, Physeolus vulgaris, Grevillea robusta, Combretum molle, Cordia africana, , sycomorous, and Camellina sinensis. other hand, the residues of Eucalyptus saligna, Macadamia integrifolia, Cupressus lusitanica, Croton megalocarpus, mearnsii, Sorghum bicolour and Mangifera indica continued to impoverish the soil in the farm fields where they occur. The farmers years attributed the good or poor crop performance in farm sections with certain types of plant residues to the decomposability as well as the levels of crop nutrients contained in these residues. The implication of these farmers' perception on the farming patterns prevailing in this region were that there was a shift toward more cultivation of crop or trees species that were associated with soil fertility enhancement.Item Nursery media effects on tamarindus indica seedling establishment(The Soil Science Society of East Africa National Research Laboratories, 2005) Kung'u, J.B.; Kihara, J.; Jaenicke, H.; Mugendi, D.N.Trees are an important component of farming systems and contribute to human needs both directly through tree products andindirectly through their influence in soil fertility. Efforts by small-scale farmers to increase trees of high value in their farms are hampered by poor quality of seedlings withlowsurvival and slow growth rate. One reason for poor seedling development is inappropriate chemical and physical properties of the growing media used. This studyattempted to find out the effect of these chemical and physical properties of the growing media used by farmers on the seedlings of Tamarindus indica (L.) and the appropriate levels for the species. Therefore, samples of the growing media usedin 6 on-farm tree nurseries in two agroecological zones in Mount Kenya region - main coffee and marginal coffee zones - were collected and tested in an on-station experiment at ICRAF headquarters, Nairobi, Kenya. The media were analyzed for chemical (nitrogen, phosphorus, calcium, magnesium) and physical (pH, total pore volume, aeration pore volume and water holding capacity) properties. The root diameter, seedling height and root and shoot dry weights of seedlings raised in the media were measured periodically. Data were analyzed for variance (ANOVA) using Genstat 4.1 release and treatments compared using Students-Newman-Keuls test.Aeration pore volume, total pore volume and wet bulk density were the physical properties that had greatest influence on seedling quality parameters especially during initial period of growth (up to 75 days). Chemical properties, on the other hand, affected seedling growth and quality parameters at later stages of growth. Important nutrients were observed to be nitrogen, organic carbon, magnesium and calcium. From the findings of this study, farmers can curtail nursery period of Tamarindus indica (L.) from 130 days to as little as 75 days.Item Aerobic mineralization and recovery of nitrogen as affected by soil organic matter status in three sites in Kenya(The Soil Science Society of East Africa National Research Laboratories, 2005) Karunditu, M.W.; Mugendi, D.N.; Kung'u, J.B.; Vanlauwe, B.Pressure on available land has increased due to high population density and other competing land-use demands which have led to reduced use of traditional fallows and subsequent decline in soil fertility. Aerobic Nmineralization potential as affected by soil organic matter status in the soil was determined by a 56 day aerobic incubation at25°C. Calliandra treatment at Maseno and Embu trials had the highest mineralization over the incubation period. This was attributed to its low quality (slow decomposition and N release) and its ability tobuild up soil organic matter (SOM) in the soil. Recovery of nitrogen in maize plants was also determined and recovery was highest at Embu trial followed by Maseno trial while Kabete trial had the lowest recoveries. Rainfall distribution and resource quality were the main factors affecting recovery of nitrogen at the three trials.Item Organic residue effects on soil physical and chemical properties in Kenya(The Soil Science Society of East Africa National Research Laboratories, 2005) Mugendi, D.N.; Waswa, B. N.; Vanlauwe, B.; Nandwa, S.; Kung'u, J.B.This study was designed to evaluate the influence of organic resource management on selected soil chemical properties in central and western highlands of Kenya. Three ongoing experiments (Kabete, Masenoand Embu) involving the integration of organic and inorganic resources as nutrient sources were selected. The choice of these experiments was based on the different organic resources applied, their Key words: Soil organic matter, soil fertility lifespan as well as their unique ecological locations that characterize most smallholder fanning areas in Kenya. These experiments involved the application of Tithonia diversijolia, Senna spectabilis, Leucaena leucocephala and Calliandra calothyrsus as organic nutrient sources to a maize crop which were compared to fertilizer and). control treatments. Soils were sampled from these experiments and analysed for inorganicnitrogen, total carbon, nitrogen, bulk density and potassium permanganate oxidizable carbon. In addition, SOMItem The Role of Indigenous Knowledge in Management of Soil Quality among Smallholders in Chuka and Gachoka Divisions, Kenya(Kenpak Colour Printers, 2005) Mairura, F. S; Mugendi, D.N.; Mwanje, J. I.; Ramisch, J. J.; Mbugua, P. K.Scientists and farmers possess qualitative knowledge of agro-ecosystems that they observe, which could be a valuable resource for science. A study based on participatory methods was conducted to determine farmers' soil quality perceptions and common soil management practices that influenced S soil fertility within fanners' fields in Chuka and Gachoka Divisions, in Meru South and Mbeere Districts Kenya. Soils characterized P by farmers were geo-referenced after which they were sampled at surface depth I (0-20 cm) for subsequent physical and n chemical analyses, to determine differences it within farmers' soil quality categories. Farmers used sensory information, based upon soil tactile and visible characteristics d to distinguish soil productivity. Indicators for distinguishing productive and non-productive S fields included crop yields and performance, a soil colour and soil texture. There were significant statistical differences among soil fertility categories, using parametric techniques (ANOVA) for key soil properties ), implying that the soils must have a, belonged to different populations and that C there was a qualitative difference in the soils c that were characterised as different by IT fanners. Soil fertility and crop management el practices that were investigated indicated g that farmers understood and consequently kJ utilized spatial heterogeneity and temporal h variability in soil quality status within their farms as a resource to maintain or enhance agricultural productivityItem Studies on the Influences of Landuse on Soil and Water Resources in Thika District, Kenya(Soil Science Society of East Africa, 2003) Karuri, A. W.; Wamicha, W. N.; Maina, D.; Bartilol, S. K.In the last three decades a decline has been observed in water and soil resources resulting from non-point or point source pollution. Landuse patterns may contribute to pollutants flowing into water or soil within a certain region. This study was carried out to investigate the influence of different landuse patterns on water and soil quality. Data collection was done from three major landuse .zones namely coffee, horticultural and Thika urban zone during the period September 1999 to June 2000. Twenty-one water samples were collected per each site along Chania River and levels of heavy metals were determined using x-ray fluorescence. In addition, twelve representative soil samples were collected per site along the Chania River and levels of heavy metals in soils were also determined. Heavy metal levels in water were found to be higher in the Thika urban site (Blue post) compared to coffee zone site (Egaad Estate) located upstream. However, the levels are still below the drinking water standards. With increase in the use of agrochemical inputs and soil erosion the levels of heavy metals in water or soil may increase in the future. Soil samples reflected higher levels of heavy metals than water but still within allowed limits. Statistical analysis further revealed a correlation between land use and heavy metals in river water as well as from the soil. Iron and zinc were found to be higher compared to other metals. Chania River receives agrochemical wastes from horticultural and coffee farms as it flows from Egaad coffee-estate to Bluepost. Therefore the levels of heavy metals at downstream site at Thika Blue post was found to be higher than levels at upstream site at Egaad coffee estate. For example zinc in river water was 2.9ppb and 1l.6ppb at Egaad coffee estate and Thika Blue Post respectively. The allowed limits for zinc in drinking water standards set by Kenya Bureau of Standards is 5.0Oppm To prevent increase of heavy metals in soil and water, there is need for proper landuse planning such as reduction of agrochemical inputs especially from the horticultural farms. Incorporating integrated pesticide control, agricultural extension or enhancing soil conservation methods such as afforestation would further reduce heavy metal pollution.Item Rating Land Qualities in Grazing Areas: A Case Study of Greyzems in South West Kenya(Soil Science Society of East Africa, 2003) Wamicha, W. N.The criteria for rating soil fertility in grazing areas is not well elaborated. This is because, the levels of pasture nutrients are wholly dependent on the; minerals to weather, organic matter to decompose, and on these two processes to release the nutrients and the soil colloids to retain those nutrients. Hence a soil fertility capability evaluation, based on the ability of the soil colloids to retain the nutrients was therefore considered to be more appropriate. Soil fertility capability is dependent on how soils retain plant nutrients. For this reason therefore, two major plant nutrients (pK)':'Vere correlated with the soil colloids; organic matter, oxides and clay minerals. The two plant nutrients were found to have moderate to high correlations with the oxalate extractable oxides (Mn%, Fe%), kaolinite and illite. That is, r=O.62, 0.56, 0.67 and 0.68 with K and r=O.84, 0.39, 0.81 and 0.80 with P respectively. A rating system was then developed combining; CEC, base saturation and % C as recommended by FAO guidelines together with oxalate extractable oxides (Mn%, Fe%) and illite to kaolinite ratios as identified in this study. For heoxides an easier criteria of using colour hues was also tested. The Greyzem classification unitswere finally classified into three soil fertility capability' groups as follows; moderate (Gleyie), low (Vertic, Haplic) and very low (Lithic). This capability classification also reflects The stage of weathering whereby the G1eyic Greyzems are the least weathered while the Lithic Greyzems are the shallowest and relatively the highly weathered. The Greyzems are therefore, Generally low in terms of soil fertility capability. Soil management in the study area should Therefore aim at raising this soil property. Of the five rating criteria used, only the organic matter can be managed with reasonable ease in order to elevate the soil plant nutrients retention capability. Therefore measures aimed at conserving the organic matter should be taken, for example, by avoiding overgrazing and grass burning.Item Low Cost Soil Fertility Management Strategies for Improving Maize Production in the Central Highlands of Kenya(Soil Science Society of East Africa, 2003) Micheni, A.; Mugendi, D.N.; Mucheru, M.; Mugwe, J.; Kung'u, J.B.; Otor, S.C.J.; Murithi, F.; Gitari, J.Continuous decline in soil productivity is a major constraint to the improvement of livelihoods of Smallholder farmers of Kenya. In highlands, levels of soil nitrogen, phosphorus and sometimes Potassium are low and the situation is worsened by the methods of cultivation that results in nutrient mining rather than nutrient build up. Low soil fertility contributes to one of the greatest challenges currently facing Kenya; inadequate food production for the rapidly growing population. There is a need to seek for environmentally friendly and economically viable technologies to assist in soil fertility improvement and hence high and sustainable crop yields. To this end, a multidisciplinary research team of scientist and farmers implemented a participatory trial in Meru South district, one of the main maize growing areas of central Kenya. The trial was farmer-researcher managed with a general objective of offering small scale resource poor farmers with feasible soil nutrient management techniques for combating soil nutrient depletion caused by continuous cropping without adequate additions of external soil fertility inputs. Preliminary results indicate that maize performance may be improved by combining fast decomposing plant biomass(e.g. Tithonia diversifolia) with half the recommended rate of nitrogen fertilizer.Item Consumption of Dryland Indigenous Fruits to Improve Livelihoods in Kenya. The Case of Mwingi Distric(Kenyatta University, 2008) Kung'u, J.B.; Kimiywe, Judith; Simitu, Parnwell Juma; Jamnadass, R.; Kindt, R.Dry areas of Kenya rely on alternative food products such as indigenous fruits to supplement their diets. Kenya has an estimated 400 indigenous fruit plants, most of which are not fully exploited This is because these species have not been fostered by agricultural and forestry institutions. IFTs show great potential for providing food, vitamins and income to communities e.g Sclerocarya birrea fruit contain 180 mg of vitamin C per 100 g, surpassing exotic lemon, orange and mango Experts have recommended a daily intake of ~ 200 g of fruits for a healthy diet, East Africa consumption is only ~ 40 g. Berche Increased IFT consumption therefore has strong potential to reduce existing micronutrient deficiencies among populations of dryland Kenya, especially in mothers and children Vangueria infausta tree and fruit survey conducted to establish intake levels of indigenous fruits in the drylands of Mwingi District in Kenya Study assessed patterns of consumption and perspectives and practices of use and cultivation of IFTs by smallholder farming communities