Botany-Scholarly Publications

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Browsing Botany-Scholarly Publications by Author "Adekanmbi, O.H."

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  • Item
    Open Access
    A Late Holocene Record of Vegetation and Climate from a Wetland in Lagos, South-western Nigeria
    (Knowledgia Scientific, 2020) Adekanmbi, O.H.; Ajikah, L.B.; Onuminya, T.O.; Ogundipe, O.T.
    Background and Objective: Information from the distribution of palynomorphs is used to infer past vegetation changes and paleo-climatic settings, characteristic of a particular environment. This palynological studies aimed to assess the distribution of palynomorphs and reconstruct the past vegetation and make inferences on the paleoclimate of a late Holocene core. Materials and Methods: Sediments samples were collected at intervals of 3 cm to a depth of 51 cm using a universal peat corer and subjected to standard palynological procedures. Prepared slides were studied with both light and scanning electron microscope. Photomicrograph of some recovered palynomorphs was imaged using Zeiss merlin scanning electron microscope. Lithological analysis and standard accelerated mass spectrometry (AMS) was also carried out to provide a calibrated accurate ratio of 14C and 13C dates. Results: Five palynoecological groups were recognized to include mangrove, freshwater swamp, riverine/lowland rainforest and fern spores suggestive of a humid climate. Absolute ages from radiocarbon dating showed the study sediments were deposited around the last 111.8±0.4 BP indicating the late Holocene. Lithology, pH and salinity analysis revealed a miscellany of sedimentary depositional environment in which the recovered palynomorphs were preserved. Conclusion: Significantly the study revealed the disappearance of mangrove vegetation notably Rhizophora sp. and Acrosticum aureum, while open vegetation dominated recovery indicating an increase in human influence on the study area.
  • Item
    Open Access
    Pollen analysis and heavy metals detection in honey samples from southern Nigeria
    (World News of Natural Sciences Scientific Publishing House „DARWIN”, 2019) Adekanmbi, O.H.; Walter, O.J.; Ikegbunam, N.C.
    Pollen analytical study of two locally produced honey samples collected from Akwa Ibom and Cross River State, Southern Nigeria were carried out in order to ascertain the preferentially foraged plants by honey bees, as well as the concentration of heavy metals. Samples were subjected to standard laboratory procedures using an acetolysis mixture (pollen analysis) and atomic absorption spectrometry (heavy metals). The results from the analysis revealed 32 taxa belonging to 17 botanical families. The number of pollen grains in the honey samples varied significantly (between 4,887 - 12,755 pollen grains), indicating their richness in pollen grains. 12 elements - Ni, Cu, Zn, Se, Br, K, Ca, Ti, Cr, Mn, Rb, and Fe were detected. Potassium had the highest concentration, followed by iron, calcium, titanium, zinc, copper, chromium, nickel, among others. What is more, in this study, some important honey plants: Spondias mombin, Daniella oliveri, Manihot esculenta, Treculia africana, Syzigium guineensis, Diospyros mespiliformis, Parkia biglobosa, Terminalia superba, Senna hirsuta, among others were found to be predominant and have been identified to be characteristic of the vegetation typical of Southern Nigeria. With regard to honey, this study gives an indication of the geographical and botanical origins, as well as types, source, and degree of contamination, and also an overall measure of honey purity. Such information, when displayed, can help consumers make informed decision when purchasing honey and will also help beekeepers to avoid possible contamination. Moreover, it will assist regulatory agencies in taking proper measures for environmental and consumer protection, since the concentration of heavy metals in honey is influenced by environmental pollution.