PDF(Pubmed)
Abstract：
High Latitude fjords can serve as sediment trap, bearing different type of proxies, from geochemical to micropaleontological ones, making them exceptional tools for paleoenvironmental reconstruction. However, some unconventional proxies can be present and can be used to depict a comprehensive and exhaustive interpretation of past changes. Here, studying a sediment core in Edisto Inlet (Ross Sea, Antarctica) we used irregular echinoid spines and ophiuroids (Ophionotus victoriae) ossicles to trace environmental changes throughout the last 3.6 kyrs BP. Irregular echinoids can serve as proxy for the organic matter content, while O. victoriae ossicles can be used as proxy for steady sea-ice cycle along with organic deposition events. O. victoriae release a high number of ossicles, making estimation about the population quite challenging; still, presence data, can be easily collected. By applying Generative Additive Models to the stratigraphical distribution of these data, we detected an environmental phase that was previously unnoticed by other traditional proxies: the Ophiuroid Optimum (2-1.5 kyrs BP). In conclusion, here we demonstrate how echinoderm presence can be used as a valuable source of information, while proving the potential of modelling binary data to detect long-term trend in Holocene stratigraphical records.
摘要：
高纬度峡湾可以作为沉积物陷阱，轴承不同类型的代理，从地球化学到微古生物学，使它们成为古环境重建的特殊工具。然而,可以存在一些非常规的代理，可以用来描述对过去变化的全面和详尽的解释。这里,研究埃迪斯托入口(罗斯海，南极洲）我们使用了不规则的棘突棘和蛇类（Ophionotusvictoriae）小骨来追踪最近3.6kyrsBP的环境变化。不规则的类孔虫可以作为有机物含量的代表，而O.维多利亚小骨可以用作稳定的海冰循环以及有机沉积事件的代表。O.维多利亚释放大量小骨，对人口的估计相当具有挑战性；尽管如此，存在数据，可以很容易地收集。通过将生成加法模型应用于这些数据的地层分布，我们检测到一个以前未被其他传统代理注意到的环境阶段：蛇形最佳（2-1.5kyrsBP）。总之,在这里，我们演示如何将棘皮动物的存在用作有价值的信息来源，同时证明了对二元数据进行建模以检测全新世地层记录中的长期趋势的潜力。
