|Budget Amount *help
¥3,900,000 (Direct Cost : ¥3,900,000)
Fiscal Year 1998 : ¥900,000 (Direct Cost : ¥900,000)
Fiscal Year 1997 : ¥3,000,000 (Direct Cost : ¥3,000,000)
The goal of the wastewater treatment used to be the removal of BOD, but nowadays, the removal of nitrogen and phosphorus is required. As the required level of treatment gets higher, we need to understand he microbial population and to make the best of microbial power to remove pollutants. In this research, we employed the fluorescence DNA probes which enables the analysis of microbial population structure for the analysis of microbial population in activated sludge in wastewater treatment plants. One of the important points about using the fluorescent DNA probes is that microbial population can be estimated without cultivation.
In this research, we analyzed the activated sludge in 20 treatment lines in 15 wastewater treatment plants in Hokkaido, Tokyo, Saitama, and Okinawa areas. Four surveys were conducted on each of the treatment plants ; November 1997, January, Nay, and August 1998. Six probes were used for the investigation which are targeted at (l)eubacteria, (2) Proteobacteria alpha-subclass, (3) Proteobacteria beta-subclass, (4) Proteobacteria gamma-subclass, (5) Gram positive GC high group, and (6) Cytophaga-Flavobacterium group.
It was demonstrated that in many of the wastewater plants, Proteobacteria (alpha- + beta- + gamma-subclasses) were the predominant group of eubacteria, and that alpha-subclass and the beta-subclass are the most predominant in the Proteobacteria. No significant relationships were found between the microbial population structure and the conditions of the wastewater treatment plants, such as location, water temperature, and the nutrient removal. But it was found that the smaller wastewater treatment plants contain more eubacteria which were not detected by the group-specific probes used in this study. In many of the wastewater treatment plants, increase in the alpha-subclass and the decrease in the Gram positive GC high group from winter to summer were observed.