城市河道内源硫介入厌氧氨氧化过程的机制研究

Anaerobic ammonium oxidation process is an important link in N-cycling pathway in aquatic environment. Endogenous sulfur is one of key elements in river systems and the role of endogenous-s in controlling anaerobic ammonium oxidation can't be disregarded. However, related studies mainly focus on autotrophic sulfur-driven denitrification, the role of endogenous sulfur in intervening in anaerobic ammonium oxidation as well as their coupled microbial processes still remain unclear. In this research, the role of endogenous-S in regulating anaerobic ammonium oxidation process is to be investigated systematically for the treated urban rivers with high-level nitrogen and low C/N ratio. The inoculation tests, lab-scale simulated experiments and field studies are to be performed. The objectives of this research are (1) to ascertain the role of endogenous-S in regulating anaerobic ammonium oxidation as well as the N-removal contribution of sulfur-driven autotrophic denitrification and anaerobic ammonium oxidation in urban river; (2) to test the possible coupled pathway of sulfur-driven autotrophic partial denitrification with anaerobic ammonium oxidation;(3)to elucidate the coupled microbial mechanisms between NR-SOB and ANAMMOX. This research is of great significance for improving the understanding of microbial process of N- and S-cycling in aquatic environment as well as solving the problem of high-level nitrogen of treated polluted urban river.

厌氧氨氧化是氮的生物地球化学循环的重要环节，作为河道生态系统重要组成元素的内源硫对其的影响作用不容忽视。然而目前关于河道内源硫对氮转化的影响研究主要针对硫自养反硝化过程，对于内源硫如何影响厌氧氨氧化的发生以及二者之间的耦合关系尚未定论。本课题针对黑臭河道治理后呈现的高氮营养盐和较低C/N比生境，通过富集培养、模拟实验与现场实证，系统研究内源硫对厌氧氨氧化过程的影响作用，定量剖析厌氧氨氧化与硫自养反硝化过程对河道的脱氮贡献，并验证是否存在“硫自养部分反硝化-厌氧氨氧化”的耦合途径；同时从分子生物学角度解析厌氧氨氧化菌（ANAMMOX）和反硝化脱硫菌（NR-SOB）在河道氮转化过程中的作用和种间生态关系，揭示河道内源硫介入厌氧氨氧化过程的机制，确定优化的协同调控策略，为阐明水圈微生物驱动氮、硫循环机制的基础理论提供有益补充，也为解决城市污染河道经治理消除黑臭后凸现的高氮营养盐问题提供技术支撑。

厌氧氨氧化是氮的生物地球化学循环的重要环节，作为河道生态系统重要组成元素的内源硫对其的影响作用不容忽视。然而，目前关于河道内源硫对氮转化的影响研究主要针对硫自养反硝化过程，对于内源硫如何影响厌氧氨氧化过程的发生以及二者之间的耦合关系尚未定论。本课题针对黑臭河道治理后呈现的高氮营养盐和较低C/N比生境，通过富集培养、模拟实验与现场实证，系统研究了不同形态硫对厌氧氨氧化过程的影响作用，发现还原态硫（硫化钠、硫代硫酸钠、单质硫和黄铁矿）均有助于硫自养部分反硝化-厌氧氨氧化的耦合过程，其中硫代硫酸钠体系的硝酸盐去除效果最佳。硝酸钙驯化含硫的河道底泥可促进厌氧氨氧化过程，并存在反硝化、厌氧氨氧化和异化硝酸盐还原成铵（DNRA）三者耦合的作用关系。针对黑臭河道治理后呈现的低C/N比和较高DO的生境，可通过促进底泥内源还原态硫的释放来强化总氮的去除，高频度低运行时间的间歇曝气模式更有助于总氮的去除。基于以上研究，还提出了一种快速启动厌氧氨氧化过程的新方法以及研制了一种混合营养型脱氮滤料，不仅为阐明水圈微生物驱动氮、硫循环机制的基础理论提供有益补充，也为强化城市河道氮素削减以及低C/N比废水 “零碳源”深度脱氮技术的研发提供技术支撑。