运用生物标志物重建古盐度的研究进展

Progress in paleosalinity reconstruction: A review of biomarker approaches

在古海洋、古环境研究领域,水体盐度重建是长期以来亟待解决的难题。在无机地球化学作为古盐度计应用日趋成熟的同时,有机地球化学指标为解决该问题提供了不同的思路和观点。经过数十年来的大量生物培养实验和环境研究,基于C_(37.4)烯酮的质量分数、古菌膜脂的ACE(archaeol and caldarchaeol ecometric)指数、长链二醇的醇指数指标(diolindex,DI)和脂类氢同位素组成等都被证明与水体盐度有相当密切的联系,可以将它们作为指示区域水体古盐度变化的参考证据。需要指出的是,由于对这些生物标志物的生物来源和合成过程了解的局限性以及其他环境因素的影响,本研究也讨论了在具体应用时需要考虑的适用范围及区域校正问题。

The reconstruction of salinity in oceans and lakes has long been a topic of sustained interest in paleoceanography. For a long time now, inorganic geochemical parameters, applied as paleosalinity indicators, are being developed, whereas organic geochemistry approaches can provide alternative tools and new insights. Over the past decades, long chain alkenone-based w(C_(37.4)), archaeal GDGT based ACE, long chain diols-based Diol Index, and hydrogen isotopes of lipid biomarkers have been developed through several culture experiments and field investigations. However, their applications are still often restricted in certain regions, given the complexity of producers and precursors of biomarkers and influence of environmental factors other than salinity. In this study,we reviewed the development and calibration of these proxies and discussed the limitation of their applications.