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.

在末次盛冰期（LGM）期间，南极大陆周围的冰架和海冰扩展影响了全球温盐环流以及南极特有的生物群。在这些冰川条件下，沿海冰穴已被确定为南极底层水形成的重要场所和海洋生物群的冰川避难所。关于这种冰穴存在于德龙宁毛德地（南极洲东部）的知识来自于雪海燕的陆地繁殖地。过去的雪海燕殖民地的记录是胃油沉积（mumiyo），它形成在巢前。放射性碳年代测定表明，鸟类占据目前无冰山脉至少在过去60 ka，这不仅意味着非冰川陆地地区，但也指出存在海洋觅食地减少海冰，因此冰穴。在拟议的项目中，我们希望使用来自东南极洲不同地区的mumiyo沉积物，以详细重建海洋和陆地环境条件。我们建议地球化学，古生物学和同位素代理，以检测雪海燕，在沿海地区的海冰和在冰川和全新世条件下的雪海燕的陆地繁殖栖息地的条件下，可用的食物资源的变化。这将有助于更好地了解海洋地球化学循环、食物网结构和海洋生态系统对冰川气候条件的反应。