Distribution and Abundance of Airborne Palynomorphs in Aku, Enugu State, Nigeria
A study of airborne palynomorphs of Aku was carried out with the use of tauber pollen sampler from October to December, 2004. A total of 3,390 palynomorphs was recorded with the breakdown as follows: October, 1248; November, 1156 and December, 1526. Out of the counted palynomorphs, pollen grains constituted 2,125.The count of 736 pollen in October was followed by a decrease to 545 in November and a further increase to 844 in December. The pollen grains belonged to 20 families of flowering plants (17 dicotyledons and 3 monocotyledons) consisting of 20 genera. The result revealed dominance of wooded shrub grassland/woodland vegetation sub-type, relics of tropical lowland rainforest and secondary
grassland. The taxa of both tropical lowland rainforest and secondary Grassland decreased from October to November and increased again in December. Fungi were the major spore contributors to the atmosphere and were dominated by the spores of Spadicoides, Curvularia, Dreschlera/Helminthosporium and Nigrospora. Pollen grains were next to fungi in total abundance and were dominated by the pollen of; Elaeis guineensis Jacq, Poaceae, Milicia excelsa Wild C.C. Berg, Irvingia wombolu Vermoesen, Syzygium guineense Engl. and Ageratum conyzoides L. December had a high influx of charred gramineae cuticles indicative of increased burning activities in the area. Fungal spores recorded per month had an inverse relationship with the monthly rainfall and relative humidity.
EE Osayi, DN Ezike, CV Nnamani