【摘要】 潮汐过程中溶解态碳的动态变化是理解湿地碳侧向输出和完善湿地碳计量的关键。以闽江河口湿地受潮汐影响的潮沟为研究对象，测定并分析潮汐过程中溶解有机碳（DOC）、溶解无机碳（DIC）、碱度（TA）、紫外可见吸收光谱参数(α₃₅₅,SUVA₂₅₄,S_275-295)的动态变化。结果表明：DOC和DIC在潮汐过程中呈现明显变化，低潮位时DOC、DIC分别为1 353、3 726μmol·L^-1,高潮位时降低至233、940μmol·L^-1, DIC、DOC及TA均与潮高呈显著负相关。潮汐过程中DIC与DOC输出比例约为1.6。光谱参数(α₃₅₅,SUVA₂₅₄)在潮汐过程中有明显变化特征，可作为示踪潮汐过程溶解有色有机物变化的手段。DIC和TA增加量的比值（～0.96）指示反硝化或硫酸盐还原是维持DIC产生的主要生物地球化学过程。更多还原

【Abstract】 The dynamic changes of dissolved carbon during tidal cycles are critical to understanding carbon lateral export and refining carbon measurement in wetlands.The variations including dissolved organic carbon, dissolved inorganic carbon, alkalinity, and UV-visible absorption spectral parameters(α₃₅₅,SUVA₂₅₄,S_275-295) during the tidal cycles were investigated in a creek within the Shanyutan wetland of the Minjiang River estuary.The results showed remarkable variations: DOC and DIC values were 1 353,3 726 μmol·L^-1 during ebb tide and 233,940 μmol·L^-1 during flood tide for DOC and DIC,respectively, and also possessed significant negative correlations with tidal height.The ratio of DIC to DOC export during the tidal process was ～1.6.The spectral parameters(α₃₅₅ and SUVA₂₅₄) varied significantly during tidal cycles and can be applied as tracers for the dynamics of the chromophoric dissolved organic matter during tides.Inferred from the stoichiometric relationship between DIC and TA（～0.96）,the sulfate reduction processes and/or denitrification might serve as main mechanisms for inorganic carbon export.更多还原