Influence of growth manner on nitrifying bacterial communities and nitrification kinetics in three lab-scale bioreactors |
| |
| Authors: | Feng Wang Yi Liu Jinghan Wang Yalei Zhang Haizhen Yang |
| |
| Institution: | (1) Key Laboratory of Yangtze River Water Environment, Ministry of Education, Tongji University, Shanghai, 200092, China;(2) Shanghai Environmental Protection Limited Company, Shanghai Academy of Environmental Sciences, Shanghai, 200233, China |
| |
| Abstract: | The effects of growth type, including attached growth, suspended growth, and combined growth, on the characteristics of communities
of ammonia-oxidizing bacteria (AOB) and nitrite-oxidizing bacteria (NOB) were studied in three lab-scale Anaerobic/Anoxicm-Oxicn (AmOn) systems. These systems amplified activated sludge, biofilms, and a mixture of activated sludge and biofilm (AS-BF).
Identical inocula were adopted to analyze the selective effects of mixed growth patterns on nitrifying bacteria. Fluctuations
in the concentration of nitrifying bacteria over the 120 days of system operation were analyzed, as was the composition of
nitrifying bacterial community in the stabilized stage. Analysis was conducted using polymerase chain reaction-denaturing
gradient gel electrophoresis (PCR-DGGE) and real-time PCR. According to the DGGE patterns, the primary AOB lineages were Nitrosomonas europaea (six sequences), Nitrosomonas oligotropha (two sequences), and Nitrosospira (one sequence). The primary subclass of NOB community was Nitrospira, in which all identified sequences belonged to Nitrospira moscoviensis (14 sequences). Nitrobacter consisted of two lineages, namely Nitrobacter
vulgaris (three sequences) and Nitrobacter alkalicus (two sequences). Under identical operating conditions, the composition of nitrifying bacterial communities in the AS-BF system
demonstrated significant differences from those in the activated sludge system and those in the biofilm system. Major varieties
included several new, dominant bacterial sequences in the AS-BF system, such as N. europaea and Nitrosospira and a higher concentration of AOB relative to the activated sludge system. However, no similar differences were discovered
for the concentration of the NOB population. A kinetic study of nitrification demonstrated a higher maximum specific growth
rate of mixed sludge and a lower half-saturation constant of mixed biofilm, indicating that the AS-BF system maintained relatively
good nitrifying ability. |
| |
| Keywords: | |
| 本文献已被 PubMed SpringerLink 等数据库收录！ |
|
