Browsing by Author "Gathuku, George Njagi"

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    Spatial Ramifications of Dodder Infestation on Urban Ornamentals in Mombasa, Kenya
    (Scientific Research Publishing, 2020-08) Ngare, Innocent Osoro; Koske, James Kibii; Muriuki, John Njagi; Gathuku, George Njagi; Adiel, Ruth Kangai
    Dodders are cosmopolitan generalist holoparasites that forage on a commu nity of plant species ranging from shrubs, trees and herbaceous. In this study, we employ mixed method research design that involved use of questionnaires and dodder host sampling matrix. Host identification and naming was car ried out by ecological Android PlantNet Plant App version 3.0.5. Respon dents sample size was determined by Krejcie and Morgan sampling formula. Results show that dodder was fast spreading through spatial retrospective sat ellite Landsat imagery analysis. Dodder was known by the majority of re spondents (97.1%) where the exploratory analysis score shows that respon dents’ constituency of residence influenced their understanding of dodder (F(5, 361) = 5.329, P = 0.000). The mode of parasitism between dodder & the hosts varied as some ornamental trees, shrubs and herbaceous plants were either affected moderately or extremely. The study recommends use of bio technological dodder control approaches through transgenic plants biotech nology and plant breeding to develop resistance towards dodder plant para sites.
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    Urban climate variability trend in the coastal region of Mombasa Kenya
    (Academic Journals, 2020) Ngare, Innocent Osoro; Koske, James Kibii; Muriuki, John Njagi; Chitechi, Evelyn Wemali; Gathuku, George Njagi
    The world population in global south countries is increasing. This fast growth has heightened urban ecological footprint that contributes to anthropogenic forcing triggering of the climate system. From this study, climate variability trend dynamics in Mombasa County, a coastal urban area in Kenya was examined. A retrospective study was done (1989-2019) to determine the changes in temperature and rainfall in the area of study. The results show that climate variability was experienced in Mombasa with a maximum temperature t=-5.628, df=23, P:0.000 and a minimum of t= -5.401, df=23, P:0.000, total rainfall t=2.025, df=23, P:0.275. The linear regression analysis shows rainfall variation y = -9.588x + 1217.1 and temperature y =0.0258x + 29.888 with an increase of +0.4°C. The annual maximum temperature averages show heterogeneous distribution from kurtosis coefficient with little observed skewness.