Bacterial productivity in ponds used for culture of penaeid prawns

Abstract

The quantitative role of bacteria in the carbon cycle of ponds used for culture of penaeid prawns has been studied. Bacterial biomass was measured using epifluorescence microscopy and muramic acid determinations. Bacterial growth rates were estimated from the rate of tritiated thymidine incorporation into DNA. In the water column, bacterial numbers ranged from 8.3×10⁹ 1⁻¹ to 2.57×10¹⁰ 1⁻¹ and production ranged from 0.43 to 2.10 mg Cl⁻¹ d⁻¹. In the 0–10 mm zone in sediments, bacterial biomass was 1.4 to 5.8 g C m⁻² and production was 250 to 500 mg C m⁻² d⁻¹. The results suggested that most organic matter being supplied to the ponds as feed for the prawns was actually being utilized by the bacteria. When the density of meiofauna increased after chicken manure was added, bacterial biomass decreased and growth rates increased.