Pyrogenic carbon, also called black carbon (BC), is produced by biomass burning as well as by fossil fuel combustion and is an important slow-cycling component in the global carbon cycle. BC occurs in a fraction of marine dissolved organic carbon, and this is called dissolved BC (DBC). Marine DBC has been considered the ultimate repository for fluvial DBC; however, the environmental dynamics of marine DBC have not been well documented. In this study, vertical DBC profiles from the surface to the deep layers of the western subarctic Pacific and its marginal seas were analyzed using the benzenepolycarboxylic acid (BPCA) method. DBC concentrations tended to be highest in the surface layer and decreased with increasing depth, except for those in the Bussol’ Strait located in the Kuril Islands between the Sea of Okhotsk and the North Pacific. Vertical distributions of the condensation degree index of DBC (i.e., the ratio of B5CA and B6CA to all BPCAs) did not show a general trend with depth. Atmospheric deposition of BC is likely a major source of DBC in the surface layer. In the intermediate layer, the DBC concentration and the condensation degree index in the Bussol’ Strait were higher than those in the western subarctic Pacific. The occurrence of highly condensed DBC observed in the Bussol’ Strait was accompanied by low salinity and a high DO concentration, indicating that DBC is transported from the shelf sediments of the Sea of Okhotsk to the Bussol’ Strait by dense shelf water (DSW) and Okhotsk Sea Intermediate Water (OSIW). The DBC concentration and the condensation degree index in the intermediate layer of the Bering Sea and the Kamchatka Strait (located in the Aleutian Islands between the Bering Sea and the North Pacific) were higher than those in the western subarctic Pacific but lower than those in the Bussol’ Strait; this suggests that DBC from the slope sediments in the Bering Sea is transported to the Kamchatka Strait by the East Kamchatka Current and that the DBC flux from the slope sediments of the Bering Sea is lower than that involving the DSW in the Sea of Okhotsk, which accompanies the resuspension of shelf sediments. The results of this study imply that sedimentary BC is an important source of water column DBC in marginal seas and the adjacent open ocean.

热解碳，也称为黑碳（BC），是由生物质燃烧以及化石燃料燃烧产生的，是全球碳循环中重要的慢循环成分。BC发生在一部分海洋溶解有机碳中，这称为溶解BC（DBC）。海洋DBC被认为是河流DBC的最终存储库；但是，海洋DBC的环境动力学尚未得到充分记录。在这项研究中，使用苯多羧酸（BPCA）方法分析了北北极西部太平洋及其边缘海从表层到深层的垂直DBC剖面。除了位于Bussol海峡的DBC浓度，表层的DBC浓度趋于最高，并随深度的增加而降低。 位于鄂霍次克海和北太平洋之间的千岛群岛。DBC冷凝度指数的垂直分布（即B5CA和B6CA与所有BPCA的比例）没有显示出随深度变化的总体趋势。BC的大气沉积可能是表层DBC的主要来源。在中间层，Bussol海峡的DBC浓度和凝结度指数高于西北极太平洋。在布索尔海峡观测到高浓度DBC的同时，还伴随着低盐度和高溶解氧浓度，这表明DBC通过浓密的架子水（DSW）从鄂霍次克海的陆架沉积物运到布索尔海峡。鄂霍次克海中间水（OSIW）。 在白令海和北太平洋之间的阿留申群岛中，该比例高于西亚北极太平洋，但低于布索尔海峡。这表明白令海斜坡沉积物的DBC由东堪察加海流运至堪察加海峡，白令海斜坡沉积物的DBC通量比鄂霍次克海的DSW低。伴随着架子沉积物的重悬。这项研究的结果表明，在边缘海和邻近的公海中，沉积BC是水柱DBC的重要来源。