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Central Province, Kenya

Webala P.W.,Karatina University | Musila S.,National Museums of Kenya | Makau R.,National Museums of Kenya
Acta Chiropterologica | Year: 2014

Population fluctuations, roost site selection and diet of straw-coloured fruit bats, Eidolon helvum (Kerr, 1792) were studied for > one year in western Kenya. Total counts of bats at three identified roosts varied from 7,000 to 48,000 individuals. The bats moved between roosts within the same general area, probably reflecting seasonal variation in the availability of preferred foods and/or harassment and direct persecution at some roost sites by the rural community. Our study suggests that tree density and number of branches on trees were important factors in roost site selection for E. helvum, and the removal of roost trees has serious ramifications for their conservation in the region. Germination experiments and observations at roost sites indicated that E. helvum consumed fruits from 31 plant species of 16 families, potentially assisting in the dispersal of their seeds. Further monitoring is needed to provide a complete picture of the status and migration patterns of E. helvum in Kenya. Additionally, because the bats were viewed negatively and persecuted by roost tree clearance and direct eradication attempts, an education and community outreach programme in local schools and communities is proposed for the long-term conservation of viable populations of E. helvum in western Kenya. © Museum and Institute of Zoology PAS. Source

Kamiri H.,Karatina University | Kreye C.,University of Bonn | Becker M.,University of Bonn
Wetlands Ecology and Management | Year: 2013

Agricultural land use changes differentially affect soil fertility and crop production potential of wetlands. We studied East African wetlands with contrasting hydro-geological characteristics (high- and lowland floodplains and valley swamps). Land uses ranged from no use and grazing over crop production in flooded and drained fields to abandonment. We classified the dynamics of wetlands' conversion into agricultural sites and assessed selected soil fertility attributes associated with land use changes, and their effect on the crop production potential in aerobic and anaerobic soils. A conversion of pristine wetlands, differing in soil physical and chemical attributes, into sites of production tended to negatively affect soil total C and N. Effects were stronger with soil drainage and in the coarse-textured soils of the lowland floodplain and the mid-hill valleys. Mineral P application in drained valleys significantly increased available soil P. Crop response followed these patterns with usually higher biomass accumulation and nutrient uptake in flooded than aerobic soils. Wetlands of fine soil texture in the highlands appeared more resilient than coarse-textured soils, particularly when drained. Enhanced crop performance in flooded soils indicates the possibility for partial recovery of the production potential and the rehabilitation of some wetlands. © 2013 Springer Science+Business Media Dordrecht. Source

Gichunge C.,Karatina University | Harris N.,Griffith University | Tubei S.,Griffith University | Somerset S.,Australian Catholic University | Lee P.,Griffith University
Journal of Hunger and Environmental Nutrition | Year: 2015

The objective of this cross-sectional study was to assess the interaction of food insecurity, social support, and vegetable intake among resettled Burundian, Congolese, and Rwandan African refugees in Australia. A total of 71 household food preparers were recruited through purposive sampling. Eighteen percent of the participants experienced food insecurity. Participants with low education and no social support were 5 and 4 times more likely to be food insecure, respectively. There were no significant differences in vegetable intake. Results indicate that food insecurity is more prevalent among postresettlement African refugees compared to the general Australian population and is associated with social support and education. Strategies to enhance education and social support networks for resettled African refugees may work toward alleviating food insecurity among this group. Copyright © Taylor & Francis Group, LLC. Source

Kebwaro J.M.,Karatina University | He C.H.,Xian University of Science and Technology | Zhao Y.L.,Xian University of Science and Technology
Nuclear Instruments and Methods in Physics Research, Section B: Beam Interactions with Materials and Atoms | Year: 2016

Radiative capture reactions are of interest in shielding design and other fundamental research. In this study the reproducibility of (n,γ) reactions in Pb when cross-section data from different ENDF/B releases are used in the Monte-Carlo code, MCNP, was investigated. Pb was selected for this study because it is widely used in shielding applications where capture reactions are likely to occur. Four different neutron spectra were declared as source in the MCNP model which consisted of a simple spherical geometry. The gamma ray spectra due to the capture reactions were recorded at 10 cm from the center of the sphere. The results reveal that the gamma ray spectrum produced by ENDF/B-V is in reasonable agreement with that produced when ENDF/B-VI.6 is used. However the spectrum produced by ENDF/B-VII does not reveal any primary gamma rays in the higher energy region (E > 3 MeV). It is further observed that the intensities of the capture gamma rays produced when various releases are used differ by a some margin showing that the results are not reproducible. The generated spectra also vary with the spectrum of the source neutrons. The discrepancies observed among various ENDF/B releases could raise concerns to end users and need to be addressed properly during benchmarking calculations before the next release. The evaluation from ENDF to ACE format that is supplied with MCNP should also be examined because errors might have arisen during the evaluation. © 2016 Elsevier B.V. All rights reserved. Source

Oyugi D.O.,Jaramogi Oginga Odinga University of Science and Technology | Mavuti K.M.,University of Nairobi | Aloo P.A.,Karatina University | Ojuok J.E.,Kenya Marine and Fisheries Research Institute | Britton J.R.,Bournemouth University
Hydrobiologia | Year: 2014

Habitat suitability indices indicate how fish species respond to different habitat types. We assessed effects of habitat characteristics on fish distribution in an equatorial lake, Lake Naivasha, Kenya, where habitats vary according to substrate, depth and turbidity. Using monthly data between 2008 and 2010 using multi-mesh gill nets, catch per unit effort was used as a relative abundance measure to identify how habitat variables drive fish distribution. The focus was on commercial fishes: two introduced species (Cyprinus carpio and Micropterus salmoides) and two naturalised species (Oreochromis leucostictus and Tilapia zillii). Analyses revealed distinct preferences for different habitat variables by all commercial species except for C. carpio. For example, O. leucostictus preferred shallow waters with silt-clay substrates whilst M. salmoides preferred deeper waters with sandy/rocky substrates. Conversely, C. carpio showed no specialised habitat requirements. Niche overlaps were significantly lower between O. leucostictus and its respective sympatric species than between other species, a likely result of its territorial behaviour. The continued environmental degradation of Lake Naivasha may imperil the preferred habitats of the niche restricted M. salmoides, O. leucostictus and T. zillii. By contrast, the ubiquity of C. carpio may facilitate their invasion, and consequently sustain their dominance in the lake's commercial fishery. © 2014 The Author(s). Source

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