Nitrogen dynamics and its association to metabolically active microbial populations were assessed in two vertical subsurface vertical flow (VF) wetlands treating urban wastewater. These VF wetlands were operated in parallel with unsaturated (UVF) and partially saturated (SVF) configurations. The SVF wetland exhibited almost 2-fold higher total nitrogen removal rate (5 g TN m⁻² d⁻¹) in relation to the UVF wetland (3 g TN m⁻² d⁻¹), as well as a low NO_x-N accumulation (1 mg L⁻¹ vs. 26 mg L⁻¹ in SVF and UVF wetland effluents, respectively). After 6 months of operation, ammonia oxidizing prokaryotes (AOP) and nitrite oxidizing bacteria (NOB) displayed an important role in both wetlands. Oxygen availability and ammonia limiting conditions promoted shifts on the metabolically active nitrifying community within ‘nitrification aggregates’ of wetland biofilms. Ammonia oxidizing archaea (AOA) and Nitrospira spp overcame ammonia oxidizing bacteria (AOB) in the oxygenic layers of both wetlands. Microbial quantitative and diversity assessments revealed a positive correlation between Nitrobacter and AOA, whereas Nitrospira resulted negatively associated with Nitrobacter and AOB populations. The denitrifying gene expression was enhanced mainly in the bottom layer of the SVF wetland, in concomitance with the depletion of NO_x-N from wastewater. Functional gene expression of nitrifying and denitrifying populations combined with the active microbiome diversity brought new insights on the microbial nitrogen-cycling occurring within VF wetland biofilms under different operational conditions.

在处理城市废水的两个垂直地下垂直流（VF）湿地中评估了氮动力学及其与代谢活性微生物种群的关系。这些VF湿地与非饱和（UVF）和部分饱和（SVF）配置并行运行。的SVF湿地表现出几乎高2倍总氮的去除率（5克TN米^-2 d ^-1）相对于所述UVF湿地（3克TN米^-2 d ^-1），以及一个低NO _X -氮积累（1 mg L ^-1与26 mg L ^-1分别在SVF和UVF湿地废水中）。运转6个月后，氨氧化原核生物（AOP）和亚硝酸盐氧化细菌（NOB）在这两个湿地中都发挥了重要作用。氧气的可用性和氨的限制条件促进了湿地生物膜“硝化聚集体”内新陈代谢活跃的硝化群落的转移。氨氧化古细菌（AOA）和硝化螺旋藻（Nitrospira spp）克服了两个湿地氧层中的氨氧化细菌（AOB）。微生物定量和多样性评估显示，硝化细菌与AOA之间呈正相关，而硝化螺菌与硝化细菌呈负相关。和AOB人口。反硝化基因的表达主要在SVF湿地的底层增强，与废水中NO _x -N的消耗同时发生。硝化和反硝化种群的功能基因表达与活跃的微生物组多样性相结合，为在不同操作条件下VF湿地生物膜内发生的微生物氮循环提供了新的见识。