Microflora in the Water and Sediment of Freshwater Culture Ponds

Abstract

Qualitative and quantitative investigation was performed on the bacterial populations in the water and sediment of the culture ponds rearing carp and goldfish from May 1982 to March 1983. Microflora in the water and sediment was diverse, and major components in the water were Acientobacter, Moraxella, Pseudomonas, Flavobacterium-Cytophaga, Vibrio-Aeromonas, Enterobacteriaceae, Bacteroides type A and other Bacteroidaceae. In addition to these bacteria, major bacteria in the sediment consisted of coryneforms, Bacillus, Micrococcus and Clostridium. Obligate anaerobes were further classified as follows: Bacteroides, 15 species; Fusobacterium, 3 species; Clostridium, 18 species; Peptococcus, 1 species; Peptostreptococcus, 2 species and unidentified strains. It was suggested that the difference of the microflora between glass aquaria and culture ponds may mainly depend on the diversity of the environment for bacterial populations.
Total aerobic bacteria including facultative anaerobes were 10³ to 10⁵ml^-1 and 10⁶ to 10⁷g^-1 and total anaerobic bacteria were ⟨2×10¹ to 10⁴ml^-1 and 10³ to 10⁶g^-1 in the water and the sediment, respectively. Total anaerobic bacteria were found to correlate with water temperature or COD.