黑潮区颗粒有机碳和生物硅输出的^(234)Th/^(238)U不平衡示踪

Export Fluxes of POC and Biogenic Silica in the Kuroshio by Means of ^(234)Th/^(238)U Disequilibria

对东海陆架外黑潮区颗粒有机碳(POC)和生物硅(bSiO2)的研究表明:台湾东北部黑潮主流真光层(100 m)POC和bSiO2的平均浓度分别为3.31μmol/L和0.68μmol/L;234Th/238U不平衡法获得POC和bSiO2的输出通量分别为3.7 mmol/(m2·d)和1.6 mmol/(m2·d).黑潮沿东海陆架北进过程中,POC和bSiO2的含量及输出通量均呈增加趋势.位于日本西南的黑潮主流中,POC和bSiO2的平均浓度分别为3.85μmol/L和2.63μmol/L,输出通量分别为6.7 mmol/(m2·d)和4.0 mmol/(m2·d).黑潮与陆架水形成的锋面区,POC和bSiO2浓度均高于黑潮主流.

To reveal the primary characteristics of the POC and biogenic silica （bSiO2 ） in the Kuroshio, as well as their export from the euphoric zone, POC, bSiO2 and 234Th were examined. The average con- centrations of POC and bSiOz were 3.31 μmol/L and 0.68 μmol/L in the main Kuroshio stream to north- east Taiwan respectively, corresponding to their respective export fluxes of 3.7 retool/（ m2 d ） and 1.6 mmol/（m2 d）. Along the flow of Kuroshio northwards, the concentrations of both POC and bSiO2 increased to a varying degree. To southwest Japan, the contents of POC and bSiO2 increased up to 3.85 μmol/L and 2.63 μmol/L respectively. The export fluxes of POC increased to 6. 7 retool/（ m2 d）, accompanying the bSiO2 flux of 4.0 mmol/（ m2 d）. The average concentrations of POC and bSiO2 in the Kuroshio frontal zone were higher than the values in the main stream.