Marine ecosystem response to late Pleistocene climate conditions- evidence from snow petrel stomach oil deposits ("mumiyo") in East Antarctica

海洋生态系统对更新世晚期气候条件的响应——来自东南极洲雪海燕胃油沉积物（“mumiyo”）的证据

• 批准号: 424214250
• 负责人: Dr. Sonja Berg
• 金额: --
• 依托单位: Institut für Geologie und Mineralogie
• 依托单位国家: 德国
• 项目类别: Infrastructure Priority Programmes
• 财政年份: 2019
• 资助国家: 德国
• 起止时间: 2018-12-31 至 2022-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/424214250?language=en
• 关键词: Marine; ecosystem; response; late; Pleistocene

During the Last Glacial Maximum (LGM) expanded ice shelves and sea ice around the Antarctic continent affected global thermohaline circulation as well as endemic Antarctic biota. Under these glacial conditions coastal polynyas have been identified as important sites of Antarctic Bottom Water formation and as glacial refuges for marine biota. Knowledge about the existence of such polynyas off Dronning Maud Land (East Antarctica) comes from the in-land breeding sites of snow petrels. Records of past snow petrel colonies are stomach oil deposits (mumiyo), which form in front of the nests. Radiocarbon dating showed that the birds occupied the presently ice-free mountain ranges at least during the past 60 ka, which does not only imply un-glaciated terrestrial areas, but also points to the existence of marine feeding grounds with reduced sea ice, hence polynyas. In the proposed project we want use mumiyo deposits from different regions in East Antarctica for detailed reconstructions of marine and terrestrial environmental conditions. We suggest geochemical, paleontological and isotopic proxies to detect changes in the available food resources for snow petrels, in sea ice in coastal regions and in conditions at the terrestrial breeding habitat of snow petrels under glacial and Holocene conditions. This will lead to a better understanding of biogeochemical cycles, food web structure and the response of marine ecosystems to glacial climate conditions.

末次盛冰期（LGM）南极大陆周围冰架和海冰的扩张影响了全球温盐环流和南极特有的生物群。在这些冰川条件下，海岸冰融区已被确定为南极底水形成的重要地点和海洋生物群的冰川避难所。关于在Dronning Maud陆地（东南极洲）附近存在这种多冰湖的知识来自于雪海燕的内陆繁殖地。过去雪海燕栖息地的记录是在巢前形成的胃油沉积物（mumiyo）。放射性碳定年法表明，至少在过去60 ka期间，这些鸟类占据了目前无冰的山脉，这不仅意味着没有冰川覆盖的陆地地区，而且还表明存在海冰减少的海洋觅食地，因此存在多冰湖。在拟议的项目中，我们希望利用东南极洲不同地区的木乃伊沉积物详细重建海洋和陆地环境条件。我们建议利用地球化学、古生物学和同位素等指标来检测冰川和全新世条件下雪海燕可利用食物资源、沿海地区海冰和陆地雪海燕孳生地条件的变化。这将有助于更好地了解生物地球化学循环、食物网结构和海洋生态系统对冰川气候条件的响应。