Research On The Influence Of Trace Copper Ion On Microbial Biodiversity Of Phosphorus Removal Bacteria In SBR

Phosphorus removal is an important part in sewage treatment. As there is not enough research on phosphorus removal bacteria, we choose the sequencing batch reactor(SBR) as the experiment object, and the polymerase chain reaction-denaturing gradient gel electrophoresis(PCR-DGGE) technique is used to study the influence under four kinds of concentrations of copper ions on microbial biodiversity of four phosphorus removal bacteria. These bacteria are Actinobacteria,α-proteobacteria,β- proteobacteria and Acidobacterium.At first the research focus on microbial community structure of Acidobacterium andα-proteobacteria before and after dosing of trace copper ion. The Acidobacterium has a great change of community structure when theα-proteobacteria is even more greater before and after dosing of trace copper ion. Those two kinds of phosphorus removal bacteria are affected largely by the environment, a slight change in environment may lead a large change on community structure. They are also sensitive to water quality, and can adjust their community structure with the change in time, andα-proteobacteria is far more sensitive. The two kinds of phosphorus removal bacteria show adaptability with the existence of copper ion as there is no big change on diversity index. The diversity indices ofα-proteobacteria appear an upward trend at four kinds of concentration of 1, 2, 3.5 mg/L copper ion, and a lower concentration of copper ion promotes bacteria growth tinily.Next is the research on microbial community ecological succession of the four kinds of phosphorus removal bacteria in the system after dosing 1mg/L copper ion. Actinobacteria andα-proteobacteria begin to adjust their community structure after a stable phase. The diversity indices ofα-proteobacteria are lower, and show a upper trend basically. The diversity indices of the four kinds of phosphorus removal bacteria have not changed much during the whole process. There are large changes in population structure, whose similarity is in fluctuations. In comparison, Actinobacteria andβ- proteobacteria are less sensitive to copper ion. Those four kinds of phosphorus removal bacteria adapt to the environment and adjust their community structure gradually.