【摘要】 本研究基于2022年3月在杭州湾海域的航次调查，阐述了春季杭州湾及其邻近海域溶解氧化亚氮（N₂O）的空间分布特征与海-气交换通量，并分析其影响因素。结果表明，春季杭州湾及其邻近海域表层水体溶解N₂O的浓度与饱和度范围分别为12.5～21.3 nmol·L^-1和115%～183%,其中，上、中、下游N₂O浓度平均值分别为17.2±2.9、14.1±0.8和13.2±0.7 nmol·L^-1,饱和度平均值分别为151%±17%、125%±6%和123%±6%,所有站位的溶解N₂O均处于过饱和状态。表层水体N₂O浓度和饱和度的分布显示出明显的空间差异性，高值集中在上游，且自西向东逐渐递减，中、下游呈现自北向南逐渐递减的趋势。温度、河口混合、河流输入和生物过程对春季杭州湾及其邻近海域溶解N₂O的分布具有重要影响。N₂O海-气交换通量范围为11.4～71.2μmol·m^-2·d^-1,平均值为29.5±16.0μmol·m^-2·d^-1。与国内其他河口、海湾相比，杭州湾的N₂O海-气交换通量相对较高，N₂O释放潜力大。根据海域面积，本研究初步估算春季杭州湾及其邻近海域N₂O的释放量为3.5×10⁵ mol·d^-1,表明其在大气N₂O排放中扮演着重要的角色。更多还原

【Abstract】 Based on a survey in Hangzhou Bay in March 2022, the distribution and sea-air exchange flux of N₂O in Hangzhou Bay and its adjacent waters in spring were investigated, and the influencing factors were analyzed. The dissolved N₂O concentration and saturation of surface water were 12.5-21.3 nmol·L^-1 and 115%-183%, respectively. The average N₂O concentration in the upper, middle and lower waters were 17.2±2.9, 14.1±0.8 and 13.2±0.7 nmol·L^-1, respectively, and the average saturation were 151%±17%, 125%±6% and 123%±6%, respectively. Dissolved N₂O in all sampling sites were in a supersaturated state. The spatial distribution of N₂O concentration and saturation in the surface water exhibited significant variations, with high values concentrated in the upstream area and gradually decreasing from west to east, while these showed a decreasing trend from north to south in middle and lower areas. The distribution of N₂O in the Hangzhou Bay and its adjacent waters was influenced by multiple factors such as temperature, estuarine mixing, river input and in situ bioproduction. The sea-air N₂O exchange flux ranged from 11.4 to 71.2 μmol·m^-2·d^-1, with an average of 29.5±16.0 μmol·m^-2·d^-1. Comparing with other domestic estuaries and bays, this is relatively high in Hangzhou Bay, indicating a significant potential for N₂O release. Combining the sea-air exchange flux and sea area, this study preliminarily estimated that the N₂O emission in Hangzhou Bay and its adjacent waters in spring was 3.5×10⁵ mol·d^-1, indicating its important role in atmospheric N₂O emissions.更多还原