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是否为今天和过去南极洲近岸的海冰状况提供了指南。与海冰每年融化的栖息地相比，受食物限制，在海冰持续多年的栖息地，扇贝可能生长得更慢，寿命更长。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，不仅与变化的海冰条件有关，还与食物的类型有关，无论是从海底回收的食物，还是海冰融化时藻类大量繁殖产生的食物。解开南极扇贝壳内捕捉到的生态印记，将增加我们对南极海冰条件变化的了解。此外，由于南极扇贝在南极冰盖首次出现时有亲戚居住，因此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。资金也将是培训新一代地球科学家在与南极浅海生境有关的化石和化学取证方面不可或缺的一部分。扇贝在世界各地分布，是构成海洋群落的不可或缺的组成部分，具有广泛的可追溯到晚泥盆世的化石记录，由于它们通常在沉积物和岩石记录中保存完好，越来越多地被认为是重要的古环境指标。该项目的主要目标是评估南极扇贝贝壳中的生长、寿命和化学成分(稳定同位素、微量元素)的差异，这些差异可能表明两种冰状态：探索者湾(EC)的持久(多年)海冰和南极麦克默多海峡西部的帆湾(BOS)的年度海冰(每年融化)。该项目将调查生长和寿命指标(物理和地球化学)，并将使用稳定氧同位素的高分辨率记录来确定是否在A.colbecki贝壳中记录了融水信号，以及该信号是否捕捉到了两个地点(EC和BOS)不同的冰行为。与微量元素有关的碳和氮的稳定同位素将被用来检查指示浮游植物水华的亚年度生产力峰值，预计在公开海洋条件下这种峰值将更加明显。将对外层方解石层的小增长增量进行评估，以确定它们是否代表两周一次的增长，如果是，它们可以为每月的环境过程提供高分辨率的替代。解开保存在A.colbecki贝壳中的环境档案，可能会被证明是了解南极洲过去不断变化的海冰条件的重要指标。资金将支持一名博士生和来自多个机构的本科生从事独立研究项目。关注南极海洋社区的网络内容将为博物馆外展而设计，每年惠及数千名中学生。这一奖项反映了NSF的法定使命，并通过使用基金会的智力优势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.