A sulfur-iron coupled ecological floating bed (EFB-SFe) was developed to enhance the denitrification capability of sulfur-based ecological floating beds (EFB-S). The denitrification performance, kinetic process and microbial community composition were explored. Results showed that sulfur-iron coupling effectively enhanced the denitrification performance of EFB, surpassing the sum of their individual effects. The average total nitrogen removal rate ranged from 1.56 to 4.56 g·m·d, with a removal efficiency of 22–84 %. The k value for the S + Fe group increased from 0.04 to 0.18 d to 0.40–0.46 d relative to the S group. The sulfur-iron coupling promoted the enrichment of denitrifying bacteria ( and ). The denitrification genes in EFB-SFe were upregulated, being 12–22 times more abundant than in EFB-S. Sulfur and iron autotrophic denitrification were identified as the main nitrogen removal processes in EFB-SFe. Overall, sulfur-iron coupling showed the potential to enhance the denitrification capacity of EFB-S for treating low-pollution water.

中文翻译：

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揭示生态浮床增强自养反硝化的硫铁耦合机制


为了提高硫基生态浮床（EFB-S）的反硝化能力，开发了硫铁耦合生态浮床（EFB-SFe）。探讨了反硝化性能、动力学过程和微生物群落组成。结果表明，硫-铁耦合有效增强了EFB的反硝化性能，超过了各自效果的总和。平均总氮去除率为1.56~4.56 g·m·d，去除率为22%~84%。相对于 S 组，S + Fe 组的 k 值从 0.04 到 0.18 d 增加到 0.40–0.46 d。硫-铁耦合促进了反硝化细菌的富集（和）。 EFB-SFe 中的反硝化基因表达上调，丰度是 EFB-S 的 12-22 倍。硫和铁自养反硝化被确定为 EFB-SFe 的主要脱氮过程。总体而言，硫-铁耦合显示出增强 EFB-S 处理低污染水的反硝化能力的潜力。