Enumeration of acetate-consuming bacteria by microautoradiography under oxygen and nitrate respiring conditions in activated sludge

摘要

Microautoradiography was used to enumerate bacteria able to take up radiolabelled acetate in activated sludge using oxygen or nitrate as electron acceptors. In each of three wastewater treatment plants (WWTP) with nitrification and denitrification (N-removal), the number of bacteria consuming acetate under aerobic and anoxic conditions was identical in contrast to the acetate removal rates. The rates were clearly lower under anoxic conditions suggesting that the specific activity of the cells and not the number of active cells was reduced under anoxic conditions.