彭强,关傲梅,齐维晓,曲久辉.基于同位素示踪和分子生物学技术对潮白河沉积物中氮还原功能特征的研究[J].环境科学学报,2021,41(11):4615-4624
基于同位素示踪和分子生物学技术对潮白河沉积物中氮还原功能特征的研究
- The characteristics of nitrogen reduction process in sediments of Chaobai River based on isotope tracer approach and molecular biology technology
- 基金项目：“一带一路”国际科学组织联盟资助项目（No.ANSO-CR-KP-2020-05）；国家自然科学基金面上项目（No.51778608）
- 彭强
- 1. 中国科学院生态环境研究中心, 中国科学院饮用水科学与技术重点实验室, 北京 100085;2. 中国科学院大学, 北京 100049
- 关傲梅
- 1. 中国科学院生态环境研究中心, 中国科学院饮用水科学与技术重点实验室, 北京 100085;2. 中国科学院大学, 北京 100049
- 齐维晓
- 清华大学环境学院, 清华大学水质与水生态研究中心, 北京 100084
- 曲久辉
- 1. 中国科学院生态环境研究中心, 中国科学院饮用水科学与技术重点实验室, 北京 100085;2. 清华大学环境学院, 清华大学水质与水生态研究中心, 北京 100084;3. 中国科学院大学, 北京 100049
- 摘要：沉积物氮还原功能对于调控和管理河流氮负荷具有重要作用.本研究选取潮白河不同区域河段表层沉积物作为研究对象，采用15N同位素示踪技术、16S rRNA扩增子测序和实时荧光定量PCR（qPCR）技术，研究了潮白河沉积物中氮还原过程（反硝化、厌氧氨氧化（anaerobic ammonia oxidation，anammox）和DNRA过程（dissimilatory nitrate reduction to ammonium，异化硝酸盐还原为铵））速率特征、相关功能基因丰度和微生物群落结构特征.结果表明：潮白河沉积物潜在反硝化、anammox、DNRA和N2O释放速率分别为（25.82±0.98）~（142.32±17.06）、（0.58±0.10）~（4.51±0.78）、（2.91±0.46）~（19.59±4.15）和（-1.09±0.17）~（3.30±0.57）nmol·g-1·h-1（以N计，下同）.沉积物氮还原以反硝化过程为主（贡献率71.86%~91.65%），DNRA也有较高的贡献率（7.03%~25.32%），anammox过程贡献较小.相关分析表明，氮还原相关功能基因丰度与潮白河沉积物氮还原过程速率存在显著正相关关系，微生物群落中α-变形菌纲、硝基螺旋菌纲、疣微菌纲、脱硫杆菌门、硬壁菌门丰度与沉积物氮还原过程速率存在显著的相关关系.
- Abstract：The nitrogen reduction function of sediments plays an important role in regulating and managing the nitrogen load of rivers. In this study, we selected the surface sediments of different sections of Chaobai River and used 15N isotope tracer approach, 16S rRNA amplicon sequencing and real-time fluorescence quantitative PCR technology (qPCR) to study the characteristics of the rates of nitrogen reduction process (denitrification, anaerobic ammonia oxidation (anammox) and dissimilatory nitrate reduction to ammonium process (DNRA)), related functional gene abundances and microbial community structure in sediments of Chaobai River. Results showed that the potential rates of denitrification, anammox, DNRA and release rate of N2O in sediments were (25.82±0.98)~(142.32±17.06), (0.58±0.10)~(4.51±0.78), (2.91±0.46)~(19.59±4.15) and (-1.09±0.17)~(3.30±0.57) nmol·g-1·h-1, respectively. Nitrogen reduction process in sediments of Chaobai River was dominated by denitrification (contribution rate:71.86%~91.65%). In addition, DNRA also had a relative high contribution rate (7.03%~25.32%) with the least contribution of anammox. Further, correlation analysis showed that the abundance of nitrogen-reduction-related functional genes had a significant positive correlation with the rates of nitrogen reduction process in sediments of Chaobai River. Moreover, the abundance of α-Proteobacteria, Nitrospiria, Verrucomicrobiae, Firmicutes and Desulfobacterota notably correlated with the rates of nitrogen reduction process.
