温度对并联式AA-MBBR工艺中微生物群落结构及代谢途径的影响

Effect of temperature on microbial community structure and metabolic pathways in a parallel connection AA-MBBR process

高原生活污水中碳氮比(C/N)较低,为了更加充分利用碳源,本试验采用并联式AA-MBBR作为处理工艺,探究温度变化对并联式AAMBBR工艺中污染物去除效率、微生物群落结构、代谢途径及功能基因的影响.结果表明,COD、TN、TP的去除效率得到了有效提升,不同温度工况下污染物去除效果优劣不同.相关功能微生物丰度在各温度工况间表现出显著差异性,反硝化菌在高于13℃的环境中,随温度的上升而受到抑制作用,反硝化基因变化趋势相同,PAOs的相对丰度在9℃时最高;PHV通过Ethylmalonyl pathway途径和甲基丙二酰辅酶A诱导产生,参与碳代谢的TCA循环和EMP途径的相关功能基因的相对丰度受温度的影响最大.

The carbon-to-nitrogen ratio(C/N)in plateau domestic wastewater is low.In order to make more full use of the carbon source,the parallel AA-MBBR was used in this experiment to investigate the effects of temperature changes on the pollutant removal efficiency,microbial community structure,metabolic pathways and functional genes in the parallel AA-MBBR.The results showed that the removal efficiency of COD,TN and TP was effectively improved,and the removal effect of pollutants under different temperatures was different.The abundance of relevant functional microorganisms showed significant variability among temperature conditions;denitrifying bacteria were inhibited with increasing temperature in environments higher than 13°C;denitrification genes showed the same trend;and the relative abundance of PAOs was highest at 9℃.And PHV was induced to be produced through the Ethylmalonyl pathway and Methylmalonyl-CoA.The relative abundance of functional genes related to the TCA cycle of carbon metabolism and related to the EMP pathway was most affected by temperature.