Nitric oxide (NO) is a key substance in atmospheric chemistry, influencing the formation and destruction of tropospheric ozone and the atmosphere's oxidizing capacity. It also affects the physiological functions of organisms. NO is produced, consumed, and emitted by soils, the effects of soil NO concentrations on microbial C and N cycling and associated trace gas fluxes remain largely unclear. This study describes a new automated 12-chamber soil mesocosm system that dynamically changes incoming airflow composition. It was used to investigate how varying NO concentrations affect soil microbial C and N cycling and associated trace gas fluxes under different moisture conditions (30% and 50% WFPS). Based on detection limits for NO, NO₂, N₂O, and CH₄ fluxes of < 0.5 µg N or C m⁻² h⁻¹ and for CO₂ fluxes of < 1.2 mg C m⁻² h⁻¹, we found that soil CO₂, CH₄, NO, NO₂, and N₂O were significantly affected by different soil moisture levels. After 17 days cumulative fluxes at 50% WFPS increased by 40, 400, and 500% for CO₂, N₂O, and CH₄, respectively, when compared to 30% WFPS. However, cumulative fluxes for NO, and NO₂, decreased by 70, and 40%, respectively, at 50% WFPS when compared to 30% WFPS. Different NO concentrations tended to decrease soil C and N fluxes by about 10–20%. However, with the observed variability among individual soil mesocosms and minor fluxes change. In conclusion, the developed system effectively investigates how and to what extent soil NO concentrations affect soil processes and potential plant–microbe interactions in the rhizosphere.

一氧化氮（NO）是大气化学中的关键物质，影响对流层臭氧的形成和破坏以及大气的氧化能力。它还影响生物体的生理功能。 NO 由土壤产生、消耗和排放，土壤 NO 浓度对微生物 C 和 N 循环以及相关微量气体通量的影响仍不清楚。这项研究描述了一种新型自动化 12 室土壤中生态系统，该系统可动态改变进入的气流成分。它用于研究不同的 NO 浓度如何影响不同湿度条件（30% 和 50% WFPS）下的土壤微生物 C 和 N 循环以及相关的微量气体通量。基于 NO、NO ₂ 、N ₂ O 和 CH ₄通量的检测限为 < 0.5 µg N 或 C m ^-2 h ^-1以及 CO ₂通量的检测限为 < 1.2 mg C m ^-2 h ^-1 ，我们发现土壤CO ₂ 、CH ₄ 、NO、NO ₂和N ₂ O受不同土壤湿度水平的显着影响。 17 天后，与 30% WFPS 相比，50% WFPS 下 CO ₂ 、N ₂ O 和 CH ₄的累积通量分别增加了 40%、400% 和 500%。然而，与 30% WFPS 相比，50% WFPS 时 NO 和 NO ₂的累积通量分别减少了 70% 和 40%。不同的 NO 浓度往往会使土壤 C 和 N 通量减少约 10-20%。然而，根据观察到的各个土壤中生态系统的变异性和微小的通量变化。 总之，所开发的系统有效地研究了土壤 NO 浓度如何以及在多大程度上影响土壤过程以及根际潜在的植物-微生物相互作用。