(Table) Carbon, nitrogen and n-alkane content and isotopic composition of bottom sediments obtained in the East Siberian Sea

The chemical composition of organic matter (Corg, Norg, d13C, d1SN, and n-alkanes) was studied in the top layer of bottom sediments of the East Siberian Sea. Possible ways were proposed to estimate the amount of the terrigenous component in their organic matter (OM). The fraction of terrigenous OM estimated by the combined use of genetic indicators varied from 15% in the eastern part of the sea, near the Long Strait, to 95% in the estuaries of the Indigirka and Kolyma rivers, averaging 62% over the sea area.本研究对东西伯利亚海海底表层沉积物中的有机质（organic matter，OM）化学组成展开分析，所涉及的指标包括有机碳（Corg）、总氮（Norg）、碳同位素比值（d13C）、氮同位素比值（d1SN）以及正构烷烃。研究提出了估算其有机质内陆源组分占比的可行方案。通过联合运用生源标志物估算得到的陆源有机质占比，在该海域东部朗海峡附近仅为15%，而在因迪吉尔卡河与科雷马河河口区域高达95%，全海域平均占比约为62%。