Abstract Climate-driven retreat of ice shelves on the eastern side of the Antarctic Peninsula has opened up new coastal marine environments, enabling the development of primary productivity. Diatom assemblages in surface sediment samples from the eastern side of the Antarctic Peninsula were analyzed to investigate the use of diatoms as paleoenvironmental indicators of changes in glacial and sea ice extent. Here we present surface sediment diatom assemblage data from samples taken on 5 cruises between 2000-2012 from the northeastern-most tip of the Antarctic Peninsula, Prince Gustav Channel, Larsen A and Larsen B embayments, and a single sample from just east of Larsen C Ice Shelf. Absolute diatom abundance increases to the northeast reflecting greater contribution of diatom valves originating from surface waters that are ice free for a longer period of time. This trend is mirrored by the relative abundance of Chaetoceros subg. Hyalochaete, a spring bloom indicator group. The genus Fragilariopsis is dominated by sea ice-associated species, including Fragilariopsis curta, Fragilariopsis cylindrus, Fragilariopsis obliquecostata, Fragilariopsis sublinearis and Fragilariopsis vanheurckii. Fragilariopsis spp. relative abundance varies inversely with Chaetoceros subg. Hyalochaete. Distributions of Thalassiosira antarctica T1 and Thalassiosira antarctica T2, interpreted as a cooler and warmer forms, respectively, while generally inverse to one another with the T. antarctica T2 more common to the northeast, are not straightforward, with a pocket of high relative abundance in Larsen B embayment. These diatom data and their comparison to modern oceanography of the eastern Antarctic Peninsula provide a basis for further paleoceanographic work in the region.

中文翻译：

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南极半岛东部地区的冰退：硅藻在理解气候变化中的应用

摘要 气候驱动的南极半岛东侧冰架退缩开辟了新的沿海海洋环境，促进了初级生产力的发展。分析了南极半岛东侧表层沉积物样品中的硅藻组合，以研究硅藻作为冰川和海冰范围变化的古环境指标的用途。在这里，我们展示了 2000 年至 2012 年间从南极半岛最东北端、古斯塔夫王子海峡、拉森 A 和拉森 B 海湾的 5 次航行中采集的样本的表层沉积硅藻组合数据，以及来自拉森 C 以东的单个样本冰架。东北部的绝对硅藻丰度增加，这反映了源自长时间无冰的地表水的硅藻阀的更大贡献。这种趋势反映在 Chaetoceros subg 的相对丰度上。Hyalochaete，春季开花指标组。Fragilariopsis 属以海冰相关物种为主，包括 Fragilariopsis curta、Fragilariopsis cylindrus、Fragilariopsisobliquecostata、Fragiliriopsis sublinearis 和 Fragilariopsis vanheurckii。脆弱藻属 相对丰度与 Chaetoceros subg 成反比。透明藻类。Thalassiosira antarctica T1 和 Thalassiosira antarctica T2 的分布，分别解释为较冷和较暖的形式，虽然通常彼此相反，T. antarctica T2 更常见于东北部，但并不简单，在 Larsen B 海湾中具有相对丰度较高的口袋。这些硅藻数据及其与南极半岛东部现代海洋学的比较为该地区进一步的古海洋学工作奠定了基础。