Using Radiochemical Data from Collapsed Ice Shelf Sediments to Understand the Nature and Timing of the Benthic Response to High-Latitude Climate Change

智力优势：PI请求支持分析以前从前拉森B冰架和拉森A冰架下面收集的多岩心和巨型岩心的沉积物。这些独特的岩心将使PI能够对南极半岛东部海域冰架坍塌后短短5年至崩塌后170年的海底响应进行时间上的综合了解。高纬度地区对气候变化的反应比地球上其他地区更快，冰架的消失是气候变暖的关键表现。PI将调查由于新鲜浮游物质重新进入沉积物-水界面而造成的新创建的海底环境和相关的生态系统。这项提议将使用一种基于自然产生的14C的新的地球化学技术，该技术可用于评估最近在前拉森A和B冰架下的沉积物中积累的有机碳的分布和清单。PI将结合~(14)C测量和~(210)Pb分析来评估沉积活性有机质的周转时间。通过比较不同地点活性有机质的分布和清单以及冰架坍塌/撤退后不同地点的生物扰动强度随时间的变化，可以评估底栖动物对冰架坍塌的响应的性质和时间。更广泛的影响：这项研究将提供重要信息，描述冰架坍塌后海底发生的变化。这项研究将支持一名研究生的研究项目。该项目汇集了来自欧洲共同体和拉里萨项目的研究人员。

Intellectual Merit: The PI requests support to analyze sediments from multi-cores and mega-cores previously collected from beneath the former Larsen B and Larsen A ice shelves. These unique cores will allow the PI to develop a time-integrated understanding of the benthic response to ice shelf collapse off the East Antarctic Peninsula over time periods as short as 5 years following ice shelf collapse up to 170 years after collapse. High latitudes are responding to climate change more rapidly than the rest of the planet and the disappearance of ice shelves are a key manifestation of climate warming. The PI will investigate the newly created benthic environments and associated ecosystems that have resulted from the re-initiation of fresh planktonic material to the sediment-water interface. This proposal will use a new geochemical technique, based on naturally occurring 14C that can be used to assess the distribution and inventory of recently produced organic carbon accumulating in the sediments beneath the former Larsen A and B ice shelves. The PI will couple 14C measurements with 210Pb analyses to assess turnover times for sedimentary labile organic matter. By comparing the distributions and inventories of labile organic matter as well as the bioturbation intensities among different locations as a function of time following ice shelf collapse/retreat, the nature and timing of the benthic response to ice shelf collapse can be assessed. Broader impacts: This study will provide important information characterizing changes occurring on the seafloor after the collapse of ice shelves. This research will support the research project of a graduate student. This project brings together researchers from both the European community and the LARISSA Project.