城市河道底泥中微生物组成及其转化氮、硫污染物的潜力

Microbial composition in sediment of urban river channel and its potential to transform nitrogen and sulfur pollutants

城市河道是城市生态系统的重要组成部分。以淮河流域某城市河道为研究对象,在了解其污染物分布特征的基础上,分析了底泥中的微生物组成,分别测定了厌氧氨氧化、硫酸盐还原氨氧化、异养反硝化、硫自养反硝化和硫酸盐还原等氮、硫转化过程的潜力。结果表明:(1)底泥中微生物以变形菌门为主,相对丰度为30%左右,同时包含与氮、硫循环密切相关的浮霉菌门、疣微菌门等。(2)底泥具有反硝化、厌氧氨氧化、硫酸盐还原等氮、硫转化的潜力。异养反硝化、硫自养反硝化、厌氧氨氧化、硫酸盐还原氨氧化的总氮平均转化速率分别为0.0108、0.0015、0.0071、0.0020 mg/(g·h),这些过程对总氮转化的贡献分别为50.5%、7.0%、33.2%、9.3%。(3)有待进一步强化底泥硫酸盐还原氨氧化或硫自养反硝化的潜力,从而促进氮、硫污染物的高效转化。

Urban river is an important component of urban ecosystem.Based on the understanding of the distribution characteristics of pollutants in an urban river(Huaihe River Basin),the microbial composition in the sediment was analyzed.The potential conversion rates of the nitrogen and sulfur conversion processe,including denitrification(heterotrophic and sulfur-autotrophic),anaerobic ammonia oxidation(nitrite-and sulfate-based)and sulfate reduction process were detected.The results showed that:(1)the microorganisms in the sediment were mainly Proteobacteria,with a relative abundance of about 30%.At the same time,it included Planctomycetes and Verrucomicrobia,which were closely related to the nitrogen and sulfur cycle.(2)The sediment had the potential of denitrification,anammox,sulfate reduction and other convertion processes for nitrogen and sulfur.The potential total nitrogen conversion rates of heterotrophic denitrification,sulfur-autotrophic denitrification,anaerobic ammonium oxidation and sulfate reductive ammonium oxidation were 0.0108,0.0015,0.0071,0.0020 mg/(g·h),respectively,with the contribution ratio as 50.5%,7.0%,33.2%,9.3%,respectively.(3)The nitrogen and sulfur cycle were expected to be strengthened by enhancing the conversion rates of sulfur-autotrophic denitrification process and sulfate-reducing ammonium oxidation process.