~. The Fcm Detection Of Low-energy N + Implantation On The Activated Sludge Microbial Flora

Activated sludge is the key functional element of biological wastewater treatment plants which employ an activated sludge process, and its biological activity depends largely on the microbial community of activated sludge. But traditional cultivation-based studies could detect only 1% to 15% of microorganism in activated sludge, since the majority of microorganisms in the environment are viable but nonculturable state. Therefore, it is important to apply the methods of cultivated-independent molecular biology to research activated sludge microbial community. The bacterical community structures in activated sludge were analyzed by a combination of fluorescent in situ hybridization with flow cytometry.The bacterical community structures of activated sludge sample from a aeration basin were analyzed with oligonucleotide probes specific for the alpha, beta, or gamma subclasses of Proteobacteria, for the Cytophaga-Flexibacterium group, for gram-positive with high G+C DNA content. The shows that the dominant bacterial community was Proteobacteria with a relative abundance of 58.3%, respectivelyα-,β-,γ- Proteobacteria were 17.8%,19.8 %,20.7 %; CF group was 21.6 %; HGC group was 19.9%.To give us a useful reference for improving the activated sludge biological activity by the low energy N⁺ beam implanting, the changes of microbial communities of activated sludge during 30keV N⁺ beam implanting were analyzed by FISH and FCM. The results showed that under the low dose of 5×10¹⁴ N⁺/cm² , the changes of bacterial communities in activated sludge were very small; under the high doses the changes of bacterial communities in activated sludge were relatively large, respectively relatively bacterial number of y-Proteobacteria increased significantly under the dose of 1×10¹⁵ N⁺/cm² and relatively bacterial number ofα-Proteobacteria increased significantly under the dose of 5×10¹⁵ N⁺/cm². The changes of bacterial communities in activated sludge under low energy N⁺ beam implanting proved that different bacterial groups had different sensitivity to low energy N⁺. It could make us to use many doses of N⁺ when we engage in activated sludge microbial community breeding.