In this study, the long-term effects of different salinities on the performance, sludge morphology and shifts in microbial communities were studied in a simultaneous anammox and denitrification (SAD) process at a C/N ratio of 0.5. Stable nitrogen removal efficiencies of 86.96 and 84.58% and nitrogen removal rates of 0.95 and 0.93 kg (m³ d)⁻¹ could be achieved under low (25 mmol l⁻¹) and moderate (50 mmol l⁻¹) salinity, respectively. However, the performance collapsed when the system was exposed to high salinity (100 mmol l⁻¹). The content of extracellular polymeric substances increased as salinity increased, which resulted in larger sizes of granular sludge under low and moderate salinities. Nevertheless, high salinity shock disintegrated granular sludge, thereby decreasing the average granule size. The Illumina-Miseq sequencing results revealed that Candidatus Jettenia was the sole salinity-tolerant AnAOB genus during the entire operation, whereas the main denitrification bacterial genera shifted from Denitrisoma under low salinity to Denitrisoma, Thauera and Ignavibacterium under high salinity. The results of this study provide a comprehensive and practical evaluation of the SAD process for organic nitrogen-rich saline wastewater treatment.

在本研究中，在 C/N 比为 0.5 的同时厌氧氨氧化和反硝化 (SAD) 工艺中，研究了不同盐度对性能、污泥形态和微生物群落变化的长期影响。^{在低盐度（25 mmol l -1}）和中度盐度（50 mmol l ^-1 ）下，可分别实现86.96和84.58%的稳定脱氮效率和0.95和0.93 kg（m ³ d）^-1的脱氮率。然而，当系统暴露于高盐度（100 mmol l ^-1）时，性能崩溃。随着盐度的增加，细胞外聚合物的含量增加，导致低盐度和中盐度下颗粒污泥的尺寸变大。然而，高盐度冲击会分解颗粒污泥，从而降低平均颗粒尺寸。Illumina-Miseq测序结果显示，整个操作过程中， Candidatus Jettenia是唯一耐盐的AnAOB属，而主要反硝化菌属从低盐度下的Denitrisoma转移到高盐度下的Denitrisoma、Thauera和Ignavibacter属。本研究结果为SAD工艺处理富含有机氮的含盐废水提供了全面、实用的评价。