典型城市河流中嗅味物质和微生物菌落特征

对某城市河流沿程水质、典型嗅味物质以及微生物群落结构进行了调查分析.结果表明:河水中2种嗅味物质〔二甲基异莰醇(2-MIB)和土臭素(Geosmin)〕的质量浓度均受到ρ(DO)的显著影响.绝对厌氧条件〔ρ(DO)<0.2mg/L〕水体中,ρ(二甲基异莰醇)和ρ(土臭素)的平均值分别为794.8和269.8ng/L;好氧条件〔ρ(DO)>2.0mg/L〕水体中,二者的平均值分别为91.6和104.7ng/L;而且ρ(DO)较低时,水体中的可疑致病菌含量升高,微生物安全性降低.控制该河流水体ρ(DO)在2.0mg/L以上,有利于抑制水体中嗅味物质的产生,可提高河流水体的微生物安全性.

Investigation on Characteristics of Odor Compounds and Bacterial Community in a Typical Urban Polluted River

Water quality,typical odor compounds and microbial community structure along a polluted urban river were investigated.The results showed that the mass concentrations of 2-MIB and Geosmin were affected remarkably by dissolved oxygen.When the mass concentration of DO was below 0.2 mg/L,the mass concentrations of 2-MIB and Geosmin in the river were 794.8 and 269.8 ng/L,respectively;when the mass concentration of DO was above 2.0 mg/L,they were 91.6 and 104.7 ng/L,respectively.Moreover,low DO mass concentrations may result in increasing numbers of pathogenic microbes and endanger the microbial safety of water quality.It is helpful to inhibit formation of odor compounds and increase microbial safety of water quality when the mass concentration of DO is above 2.0 mg/L.