Collaborative Research: The Antarctic Scallop as Key to Paleoenvironments and Sea lce Conditions: Understanding the Modern to Predict the Past

该项目的目标是发现南极扇贝Adamussium colbecki是否为今天和过去的南极洲近岸海冰状况提供了指南。与海冰每年融化的栖息地相比，扇贝在海冰持续多年的栖息地可能生长得更慢，寿命更长，食物有限。此外，在生长过程中保留在贝壳中的化学物质可能提供关键的栖息地信息，不仅与不断变化的海冰条件有关，还与食物类型有关，无论是从海底回收还是在海冰融化时由藻类繁殖产生。解开南极扇贝壳内捕获的生态印记将增加我们对南极洲海冰状况变化的了解。此外，由于南极扇贝有亲戚生活在南极冰盖首次出现的时候，扇贝壳记录可能包含有关冰盖稳定性和南极浅海历史的信息。还将提供资金，培训新一代地球科学家掌握与南极洲浅海生境有关的化石和化学法医学，扇贝分布于世界各地，是构建海洋群落不可或缺的一部分，其化石记录可追溯到泥盆纪晚期，越来越被认为是重要的古环境代用品，因为它们通常在沉积物和岩石记录中保存完好。该项目的主要目标是评估南极扇贝壳中的生长、寿命和化学（稳定同位素、微量元素）差异，这些差异可能表明两种冰态：探险家湾（EC）的持续（多年）海冰和南极洲麦克默多湾（BOS）的年度海冰（每年融化）。该项目将调查生长和寿命代理（物理和地球化学），并将使用稳定氧同位素的高分辨率记录，以确定是否在A. colbecki壳以及该信号是否捕获了两个站点（EC与BOS）的不同冰行为。将使用碳和氮的稳定同位素以及微量元素来检查表明浮游植物大量繁殖的次年度生产力峰值，预计在开阔的海洋条件下，这种峰值将更加明显。将评估外部方解石层的小生长增量，以确定它们是否代表每两周的生长，如果是，它们可以提供每月环境过程的高分辨率代理。解开保存在A.科尔贝基贝壳可能被证明是了解南极洲过去海冰状况变化的重要替代品。资金将支持博士学位。来自多个机构的学生和本科生从事独立的研究项目。该奖项反映了NSF的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

The goal of this project is to discover whether the Antarctic scallop, Adamussium colbecki, provides a guide to sea-ice conditions in nearshore Antarctica today and in the past. Scallops may grow slower and live longer in habitats where sea ice persists for many years, limited by food, compared to habitats where sea ice melts out annually. Also, the chemicals retained in the shell during growth may provide crucial habitat information related to not only changing sea-ice conditions but also the type of food, whether it is recycled from the seafloor or produced by algae blooming when sea ice has melted. Unlocking the ecological imprint captured within the shell of the Antarctic Scallop will increase our understanding of changing sea-ice conditions in Antarctica. Further, because the Antarctic scallop had relatives living at the time when the Antarctic ice sheet first appeared, the scallop shell record may contain information on the stability of the ice sheet and the history of Antarctic shallow seas. Funding will also be integral for training a new generation of geoscientists in fossil and chemical forensics related to shallow sea habitats in Antarctica.Scallops are worldwide in distribution, are integral for structuring marine communities have an extensive fossil record dating to the late Devonian, and are increasingly recognized as important paleoenvironmental proxies because they are generally well preserved in the sediment and rock record. The primary goal of this project is to assess the differences in growth, lifespan, and chemistry (stable isotopes, trace elements) archived in the shell of the Antarctic scallop that may be indicative of two ice states: persistent (multiannual) sea ice at Explorers Cove (EC) and annual sea ice (that melts out every year) at Bay of Sails (BOS), western McMurdo Sound, Antarctica. This project will investigate growth and lifespan proxies (physical and geochemical) and will use high-resolution records of stable oxygen isotopes to determine if a melt-water signal is archived in A. colbecki shells and whether that signal captures the differing ice behavior at two sites (EC versus BOS). Stable isotopes of carbon and nitrogen in association with trace elements will be used to examine subannual productivity spikes indicative of phytoplankton blooms, which are predicted to be more pronounced during open ocean conditions. Small growth increments in the outer calcite layer will be assessed to determine if they represent fortnightly growth, if so, they could provide a high-resolution proxy for monthly environmental processes. Unlocking the environmental archive preserved in A. colbecki shells may prove to be an important proxy for understanding changing sea-ice conditions in Antarctica's past. Funding will support a Ph.D. student and undergraduates from multiple institutions working on independent research projects. Web content focused on Antarctic marine communities will be designed for museum outreach, reaching thousands of middle-school children each year.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.