Bacteriological study of bottom soil of three extensive fish farm ponds

Abstract

The study was conducted for bacteriological assessment of pond bottom soil (sediment) from three selected fish ponds of Bangladesh Agricultural University. Samples were collected both in winter and summer seasons to see the seasonal variations of some bacterial genera. Physicochemical parameters of the pond water and sediment were also estimated monthly. Sediment samples were collected from the shore and middle zone of the ponds. All sediment samples were acidic. The total viable count of bacteria in pond sediment ranged from (8.5×10⁶) to (4.9×10⁹) cfu/g and bacterial count were higher in summer than in winter. A total of 16 bacterial genera were identified from the sediments. The predominant microflora consisted of Aeromonas, Flavobacterium, Cytophaga, Escherichia, Bacillus, Micrococcus, Staphylococcus, Aerococcus, Acinetobacter, Pseudomonas and Moraxella while the first five listed the greatest abundance. Aeromonas was the most dominant organism. Bacterial diversification was found higher in summer than in winter.