MICROBIAL COMMUNITIES ACROSS SELECTED DUMPSITES IN THE FEDERAL CAPITAL TERRITORY ABUJA, NIGERIA

Abstract

This research was conducted in the six area councils of the Federal Capital Territory (FCT) Abuja, Nigeria with the aim to assess the microbial communities across selected dumpsites. A total of Seventy-two (72) composite soil samples were collected. The sampling points within each area council included three levels: Contamination, Soil depths and Waste types. These soil samples were taken to the laboratory for physical, chemical and microbial characteristics. The results of the chemical and physical properties of the different dumpsites showed that the soils were predominantly loamy sand and sandy loam and were characterized by very high sand content. The isolation of microbes associated with selected dumpsites was done using the spread plate technique. A total of 87 bacteria isolates and 70 fungi isolates were isolated from contaminated soils while the non-contaminated soils recorded 36 bacteria and 20 fungi respectively across the six area councils. The highest numbers of bacteria and fungi isolates were recorded from contaminated soils at the depth of 0-15 cm, as 64 and 46 respectively. Across the area councils, the highest number of bacteria (23) and fungi (17) isolates were recorded in Abaji and Kuje area councils respectively while the least number of bacteria (18) and fungi (12) were reported in Bwari and AMAC respectively. With respect to waste types across the six area councils in the FCT, the highest number of bacteria (55) and fungi (44) isolates were found among Hospital wastes and Food Industry wastes respectively. The least number of isolates for both bacteria (19) and fungi (16) were recorded in Automobile workshop wastes. The predominant isolated bacteria include Klebsiella pneumoniae, Staphylococcus aureus and Escherichia coli while the predominant isolated fungi species include Aspergillus niger, Aspergillus flavus and Penicillium citrinum. It was concluded that the presence of bacteria and fungi loads caused by the different wastes dumped at different sites connotes a great risk to humans and the environment. Microorganisms such as Bacillus and Klebsiella species can be used as biofertilizers through composting for agricultural purposes; recycling of wastes and waste products were one of the recommendations that can be used to reduce and manage wastes.