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The knowledge of changes in past ecological conditions during the Quaternary period of Nigeria is still incipient. This necessitated a palaeoecological investigation through drilled sediments of a 45 m borehole in a swampy area at the University of Lagos, in order to ascertain possible changes in the past ecological conditions of the study area over time. Sixteen sediment samples were collected at intervals of 3 m between the depth of 0.00 m and 45.00 m and subjected to palynological, lithological, pH and salinity analyses. In the palynological study, pollen of open forest types: Alchornea cordifolia, Elaeis guineensis, Asteraceae, among others were recovered, indicating human influence over time. Pollen of Rhizophora sp., Combretaceae/Melastomataceae, Poaceae, Ceratopteris sp., Cyclosorus afer, amongst others; were also represented. Spores of Pteris sp., Nephrolepis sp. and Acrostichum sp., charred Poaceae cuticles, epidermal cells and fungal spores were also recovered. From the lithological analysis of the samples, a considerable number of lithological types were recognized, which varied in grain-size, grain sorting and grain-texture. The pH and salinity values of the sediment samples also varied considerably at different depths. However, vegetation changes during this period could be attributed to an interplay between fluctuations in the wet-dry climatic phases and anthropogenic activities. The data obtained from lithological, pH and salinity analyses reveal a mosaic of sedimentary depositional environment in which the recovered palynomorphs were preserved. Parent plants of the recovered fossil palynomorphs are still found as extant plants till today, despite the ever increasing human activities at the study area. Absolute ages were extrapolated and these revealed the period at which paleoecological changes occurred but limited to some intervals.Key words: palynomorphs, Quaternary period, climatic phases, anthropogenic, sediments.helen_olu@yahoo.com; *e-mail: olugbengaalebiosu@gmail.com ABSTRACT 169

Background: Aeropalynology is a branch of palynology that studies the content of atmospheric pollen grains and spores. The amount, concentration, and distribution of these aerospora are influenced by the seasonal flowering of parent plants and variations in climatic conditions as well as local and regional variabilities. Atmospheric pollen grains and spores are diverse and have been identified as major biological particles that trigger immune cells to release inflammatory chemical mediators, inducing respiratory-linked and allergic conditions, such as polli-nosis, among susceptible individuals. Objective: The burden of these allergic conditions on patients, families, healthcare systems, and governments has risen globally, thereby affecting developing countries, including Nigeria, wherein the financial and infrastructural institutions are not effective enough to mitigate these challenges. Avoidance of allergenic aerospora is an effective mode of addressing pollinosis with its associated conditions. However, there is a need to ascertain the atmospheric quantity, diversity, and pattern of occurrence of allergenic pollen/spores. Results: In this paper, we reviewed published articles on aeropalynology in Nigeria with atten-tion to the design and duration of the study and the used equipment. We further investigated whether identification and quantification of allergy-causing palynomorphs was part of published articles’ foci. Conclusion: The availability of such data/information is crucial for reducing epidemiological uncertainties, enhancing the diagnosis of allergic conditions, and securing a robust set of mitigation strategies and/or effective treatment of these conditions in Nigeria.

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