Investigating organic compounds in marine sediments can potentially unlock a wealth of new information in these climate archives. Here, we present pilot study results of organic geochemical features of long-chain n-alkanes and alkenones and individual carbon isotope ratios of long-chain n-alkanes from a newly collected, approximately 8 m long, located in the far reaches of the Pacific sector of the Southern Ocean. We analyzed a suite of organic compounds in the core. The results show abundant long-chain n-alkanes (C₂₉–C₃₅) with predominant odd-over-even carbon preference, suggesting an origin of terrestrial higher plant waxes via long-range transport of dust, possibly from Australia and New Zealand. The δ¹³C values of the C₃₁ n-alkane range from −29.4 to −24.8‰, in which the higher δ¹³C values suggest more contributions from C₄ plant waxes. In the analysis, we found that the mid-chain n-alkanes (C₂₃–C₂₅) have a small odd-over-even carbon preference, indicating that they were derived from marine non-diatom pelagic phytoplankton and microalgae and terrestrial sources. Furthermore, the C₂₆ and C₂₈ with lower δ¹³C values (~−34‰) indicate an origin from marine chemoautotrophic bacteria. We found that the abundances of tetra-unsaturated alkenones (C_37:4) in this Southern Ocean sediment core ranges from 11 to 37%, perhaps a marker of low sea surface temperature (SST). The results of this study strongly indicate that the δ¹³C values of long-chain n-alkanes and \( {U}_{37}^{\mathrm{k}} \) index are potentially useful to reconstruct the detailed history of C₃/C₄ plants and SST change in the higher latitudes of the Southern Ocean.

调查海洋沉积物中的有机化合物可能会释放出这些气候档案中的大量新信息。在这里，我们的长链的有机地球化学特征本试验研究结果ñ -烷烃和烯酮和长链的各个碳同位素比率ñ -烷烃从一个新收集的，约8米长，位于太平洋的远远达南大洋的一部分。我们分析了核心中的一组有机化合物。结果表明，长链正构烷烃丰富（C ₂₉ – C ₃₅）具有较高的奇偶碳优先性，这表明陆地高等植物蜡是通过可能来自澳大利亚和新西兰的粉尘的远距离运输而产生的。的δ ¹³作为C C值₃₁ ñ烷烃范围从- 29.4至- 24.8‰，其中，所述更高δ ^13个C值表明从C的贡献₄植物蜡。在分析中，我们发现中链正构烷烃（C ₂₃ – C ₂₅）具有较小的奇偶碳偏好，表明它们来自海洋非硅藻上层浮游植物，微藻类和陆生来源。此外，C₂₆和C ₂₈具有较低δ ^13个C值（〜- 34‰）表示从海洋细菌化能自养的原点。我们发现，该南部海洋沉积物芯中的四不饱和烯酮（C _37：4）的丰度范围为11％到37％，这可能是低海表温度（SST）的标志。这项研究的结果强烈表明，δ ¹³长链的C值ñ -烷烃和\（{U】_ {37} ^ {\ mathrm {K}} \）指数是重建的详细历史记录潜在有用在南大洋高纬度地区，C ₃ / C ₄植物和海表温度发生了变化。