Xiangshan Bay (XSB) is a typical semi-closed bay rich in dissolved inorganic nitrogen and anammox is one of the important processes of nitrogen cycle. The anammox bacterial abundance and diversity in XSB sediments was investigated. Five known genera were detected based on the anammox bacterial 16S rRNA gene, namely, Ca. Scalindua, Ca. Brocadia, Ca. Kuenenia, Ca. Jettenia, and Ca. Anammoxoglobus, and hzo genes affiliating with Ca. Scalindua were also discovered. The anammox bacterial 16S rRNA and hzo genes in the sediments varied from 2.10 $\times$ 10⁶ to 2.18 $\times$ 10⁷ and from 2.90 $\times$ 10⁶ to 5.48 $\times$ 10⁸ copies/g (fresh weight), respectively. Pearson correlation analysis demonstrated that the abundance of the hzo gene was positively correlated with the concentration of NH${}_4^{+}$ but negatively correlated with salinity and pH. Redundancy analysis showed that salinity, dissolved oxygen, and temperature were the three main factors influencing the community composition of anammox bacteria obtained by the anammox bacterial 16S rRNA gene. These findings help us to further understand the distribution and community composition of anammox bacteria in estuary sediments.

象山湾（XSB）是典型的半封闭海湾，富含溶解的无机氮，厌氧氨氧化是氮循环的重要过程之一。研究了XSB沉积物中厌氧菌的细菌丰度和多样性。基于厌氧细菌16S rRNA基因检测到五个已知属，即Ca。Scalindua，Ca的 加利福尼亚州布罗卡迪亚 加利福尼亚州库尼尼亚 杰特尼亚（Jettenia）和加州（Ca. Anammoxoglobus和HZO基因与联盟关系的Ca. 还发现了斯卡林杜阿（Scalindua）。沉积物中的厌氧细菌16S rRNA和hzo基因从2.10变化$\times$10 ⁶至2.18$\times$10 ⁷和2.90起$\times$10 ⁶至5.48$\times$10 ⁸份/克（新鲜重量）。Pearson相关分析表明，hzo基因的丰度与NH浓度呈正相关。${}_4^{+}$但与盐度和pH呈负相关。冗余分析表明，盐度，溶解氧和温度是影响由厌氧细菌16S rRNA基因获得的厌氧细菌群落组成的三个主要因素。这些发现有助于我们进一步了解河口沉积物中厌氧细菌的分布和群落组成。