Uncovering the long term sensitivity of Southern Ocean phytoplankton to Antarctic climate change, using novel geochemical and ancient DNA proxies

南极正在发生变化。脆弱的生态系统，从海洋哺乳动物和鸟类，到食物网底部的浮游植物，都受到全球变暖和人类活动(如捕鱼和捕鲸)的威胁。该项目的目标是通过研究过去的变化，更好地了解南极浮游植物将如何反应和适应未来的变化。早期全新世的特点是变暖，与21世纪的未来预测不相上下，在工业化加速期间，全新世/人类世过渡经历了气候变化和渔业的严重环境干扰。然而，没有来自许多主要浮游植物组的化石记录来检验它们过去的敏感性。在这个项目中，学生将利用硅藻微古生物学和沉积古DNA-最近为非化石组开发的一项新技术-重建南大洋和南极半岛过去的浮游植物变化。学生还将使用地球化学来确定核心物质的年代，并重建环境变化。研究重点本项目的目的是提供没有化石记录的物种对南极浮游植物过去变化的第一次记录。沉积物岩心中稳定同位素和微古生物的替代物将有助于限制我们对过去海洋环境的重建，从而建立对过去和未来浮游植物变化的主要原因的新理解。学生将有机会参与项目的设计，特别是关于现有的技能和对海洋、地球和生物科学的兴趣。有一系列的古生物指标可用，包括但不限于古代DNA、同位素地球化学和微古生物学。

The Antarctic is changing. Delicate ecosystems, from marine mammals and birds, to the phytoplankton at the base of the food web, are under threat from both global warming and human activities such as fishing and whaling.BackgroundThe goal of this project is to better understand how Antarctic phytoplankton will react and adapt to future changes, by examining changes in the past.The early Holocene is characterised by warming comparable to future 21st century projections, and the Holocene/Anthropocene transition experienced severe environmental disturbance from climate change and fishing during the acceleration of industrialisation. However, there are no fossil records from many of the main phytoplankton groups with which to examine their past sensitivity.In this project the student will reconstruct past phytoplankton changes in the Southern Ocean, and the offshore Antarctic Peninsula, with diatom micropalaeontology and sedimentary ancient DNA - a new technique recently developed for non-fossilising groups.The student will also use geochemistry to date the core material, and reconstruct environmental change.Research focusThe aims of this project are to provide the first records of past changes to Antarctic phytoplankton from species that do not produce a fossil record. Sediment core palaeo-proxies for stable isotopes and micropalaeontology will aid in constraining our reconstructions of past marine environments, with which to build a new understanding of the main causes of phytoplankton change both in the past and into the future.The student will have opportunities to be involved in the design of the project, particularly with respect to the existing skills and interest in marine, earth and biological sciences. A range of palaeo-proxies are available including but not limited to ancient DNA, isotope geochemistry, and micropalaeontology.