典型抗生素对地下水系统中反硝化过程的影响机理研究

微生物反硝化过程是地下水中硝酸盐最重要的脱氮形式，再生水利用和养殖业引起的抗生素污染常与硝酸盐共存，抗生素存在形式对地下水中硝酸盐反硝化过程及抗性基因产生、富集和传播的影响备受关注。本研究以典型抗生素(磺胺吡啶、土霉素、红霉素、诺氟沙星和林可霉素)为研究对象，利用批试验研究抗生素在地下水系统的存在形式；借助HPLC-TOF-MS、HPLC-ICP-MS的定性和定量能力，厘清反硝化动力学过程中抗生素存在形式对反硝化酶种类和活性的影响；凭借RNA-seq等手段探索反硝化功能基因在抗生素不同存在形式和不同输入方式下的变化过程，并建立抗性基因产生、富集与传播模式。采用野外观测和室内实验相结合的方法，从水文地球化学（污染物浓度、水化学参数）和分子生物学（群落结构、反硝化酶种类和活性、反硝化功能基因丰度和多样性、抗性基因产生、富集和传播）不同的视角综合理解典型抗生素对地下水系统反硝化过程内在影响机制。

The microbial denitrification process is the most important form of nitrate-nitrogen removal in subsurface. The reclaimed water reuse and livestock breeding caused antibiotic pollution usually co-occurrence with nitrate. Therefore, the influence of denitrification by the existence form of antibiotics and ARGs (Antibiotics Resistance Genes) in groundwater should be highly concerned. In this study, the most typical antibiotics (sulfapyridine, oxytetracycline, erythromycin, norfloxacin and lincomycin) are selected as the objective contaminants. Batch experiment is conducted to study the existing form of antibiotics after entering the groundwater system. During the denitrification kinetic processes, the influence of antibiotics on the species and activities of the denitrification enzyme is investigated by the qualitative and quantitative capability of HPLC-TOF-MS and high performance liquid chromatography-ICP-MS. High-throughput technology such as RNA-seq is used to explore the dynamic process of denitrification functional gene and ARGs under the influence of the antibiotics’ different existing forms and input modes. The combination of field investigation and laboratory experiment will be performed. By setting up a series of field observation of denitrification process and laboratory simulation column experiments, the influence mechanism of the typical antibiotics on denitrification ability and process will be clarified according to the following aspects: hydrogeochemistry (change of pollutant concentration and water chemistry parameter), microbial community (structure, evolution), denitrification enzyme (type, activity), denitrification functional gene (abundance, diversity) and ARGs (emerge, enrichment, dissemination).