Water

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Browsing Water by Author "Adamtey, Noah"

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  • Publication
    Publication
    Quantifying Effects of Selected Soil Fertility Management Techniques on Water Use Efficiency in the Central Highlands of Kenya
    (International Journal of Plant & Soil Science, 2019-10-04) Etemesi, Beryl; Ngetich, Felix K.; Kiboi, Milka N.; Zeila, Abdi; Adamtey, Noah; Mugendi, Daniel N.
    Declining rainfall distribution and variability lead to low soil moisture amounts and high evapotranspiration rates reducing water use efficiency that negatively affects crop productivity. Various soil fertility management techniques have been put in place to improve soil fertility status, but there is little attempt to asses their effects on water use efficiency and grain yields. The overall objective of the study was to quantify the effects of soil fertility management techniques on water use efficiency in the Central Highlands of Kenya. The experiment was laid out in a randomised complete block design with fourteen treatments replicated four times. Treatments were sole mineral fertilizer (Rf), crop residues + mineral fertilizer (RMf), crop residues + mineral fertilizer + animal manure (RMfM), crop residue + Tithonia diversifolia + animal manure (RTiM), crop residue + Tithonia diversifolia + rock phosphate (RTiP). Data on yield and water use efficiency was analysed using statistical analysis systems software version 9.2 at P=0.05. We observed significant (P<.0001) effect of the treatment on biomass water use efficiency during the short rains 2017, however, there was no significant effect of the treatments on grain water use efficiency because of the frequent dry spells that occurred during the study period. Soil fertility management techniques had a significant effect on grain yield at P<.0001 during the study period. Yields increased significantly (P<0001) under Rf, RMf, RMfM RTiM and RTiP by 90, 110, 120, and 176%, respectively. Water use efficiency also increased significantly under Rf, RMf, RMfM RTiM and RTiP by 200, 140, 180, 129, and 176%, respectively compared to the control. From the study, the combination of organic inputs and mineral fertilisers enhanced water use efficiency and yield hence provides a preferred practise for improved water use efficiency and yield increase.
  • Publication
    Publication
    Suitability of different data sources in rainfall pattern characterization in the tropical central highlands of Kenya
    (Heliyon, 2020-10-26) Oduor, Nathan O.; Ng'etich, Felix K.; Kiboi, Milka N.; Muriuki, Anne; Adamtey, Noah; Mugendi, Daniel N.
    Uncertainty in rainfall pattern has put rain-fed agriculture in jeopardy, even for the regions considered high rainfall potential like the Central Highlands of Kenya (CHK). The rainfall pattern in the CHK is spatially and temporally variable in terms of onset and cessation dates, frequency and occurrence of dry spells, and seasonal distribution. Appraisal of the variability is further confounded by the lack of sufficient observational data that can enable accurate characterisation of the rainfall pattern in the region. We, therefore, explored the utilisation of satellite daily rainfall estimates from the National Aeronautics and Space Administration (NASA) for rainfall pattern characterisation in the CHK. Observed daily rainfall data sourced from Kenya meteorological department were used as a reference point. The observation period was from 1997 to 2015. Rainfall in the CHK was highly variable, fairly distributed and with low intensity in all the seasons. Onset dates ranged between mid-February to mid-March and mid-August to mid-October for long rains (LR) and short rains (SR) seasons, respectively. Cessation dates ranged from late May to mid-June and mid-December to late December for the LR and SR, respectively. There was a high probability (93%) of dry spell occurrence. More research needs to be done on efficient use of the available soil moisture and on drought tolerant crop varieties to reduce the impact of drought on crop productivity. Comparison between satellite and observed rain gauge data showed close agreement at monthly scale than at daily scale, with general agreement between the two datasets. Hence, we concluded that, given the availability, accessibility, frequency of estimation and spatial resolution, satellite estimates can complement observed rain gauge data. Stakeholders in the fields of agriculture, natural resource management, environment among others, can utilise the findings of this study in planning to reduce rainfall-related risks and enhance food security.