Collaborative Research: Assessing the Impact of Holocene Climate Change on Bioavailable Strontium Isotope Ratios

圣母大学的Antonio Simonetti博士和普渡大学的Michele Buzon博士将沿着研究尼罗河流域过去4,000年来气候变化对生物可利用锶同位素特征的影响。该项目建立在两个主要研究人员以前的研究合作的基础上，这些研究人员主要根据考古动物群（土壤，动物，植物）和人类样本的锶同位素特征，为尼罗河流域内的埃及和努比亚遗址建立了古文明中的移民模式和文化互动。第一次详细调查的结果将准确地追踪尼罗河流域干旱气候导致的生物可利用锶区域分布的任何时间变化。这种方法将被证明对地球仪周围的其他地区非常有用，在这些地区，最近的气候条件在考古时期发生了显着变化。土壤、生物和化石材料中的锶同位素因地区而异，利用同位素比率，科学家可以追踪个体在其一生中如何在地区之间移动。该项目将提供洞察环境因素是否可以改变一个地区的比率。该项目将包括培训研究生掌握最先进的同位素技术，他们还将直接参与分析和解释结果。这项研究将包括美国苏丹考古研究中心（AmSARC）的参与，该中心的使命是鼓励美国和苏丹在苏丹的考古研究和合作。Simonetti和Buzon博士将通过确定动物群，土壤，植物和人类样本从合并的20个地点沿着尼罗河占领了不同的时间段，并比较这些结果，从他们现在的同行。还将从世界各地有关博物馆的藏品中获取样本。评估尼罗河流域的生物可利用锶还将依赖于综合两个PI从约250个标本中获得的现有锶同位素数据，这些标本包括从埃及（孟菲斯、Qurneh）和努比亚（Shellal、C组、Pharaonic、阿马拉西、Tombos、Kerma）遗址调查的考古人类和动物样本。这些综合结果将有助于表征同位素变异性，并更好地了解该地区的人类流动性，该地区充满了社会政治变迁和群体之间的接触。从这个项目中获得的结果将有助于阐明过去4,000年来尼罗河流域全新世气候变化的任何输入或影响。通过比较考古或古锶同位素特征的动物群样本，他们现在的同行，我们的研究将提供一个更好的了解风（风驱动）的贡献，如果有的话，在尼罗河流域。拟议的研究将对考古学家进行基于同位素的地球仪古代移民调查产生重大影响，因为气候变化是贯穿地球历史的一种现象。对于尼罗河流域来说，这涉及到非洲潮湿期的干燥，这在我们星球的其他地区也发生过。这个奖项反映了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。

Dr. Antonio Simonetti, of the University of Notre Dame, along with Dr. Michele Buzon, of Purdue University, will investigate the impact of climate change on the isotopic signature of bioavailable strontium during the last ~4,000 years within the Nile River Valley. This project builds on previous research collaborations by both principal investigators that have established immigration patterns and cultural interactions in ancient civilizations for Egyptian and Nubian sites within the Nile River Valley based primarily on strontium isotope signatures of archaeological faunal (soil, animal, plant) and human samples. The results from this first time, detailed investigation will accurately trace any temporal change in the regional distribution of bioavailable strontium driven by a drying climate within the Nile River Valley. This approach will prove extremely useful for other regions around the globe where recent climatic conditions have changed significantly during the archaeological period of interest. Strontium isotopes in soil and living and fossil materials vary on a regional basis and using isotope ratios scientists can trace how individual during their lifetimes moved between regions. This project will provide insight into whether environmental factors can change ratios in a single area. This project will include training of graduate students in state-of-the-art isotope techniques, and they will also be directly involved in analyzing and interpreting results. This study will include participation of the American Sudanese Archaeological Research Center (AmSARC), which has a mission to encourage American and Sudanese archaeological research and collaboration in Sudan.Drs. Simonetti and Buzon will expand coverage of samples investigated by determining the strontium, lead, and neodymium isotope signatures of faunal, soil, plant and human samples from combined 20 sites along the Nile River occupied over various time periods, and compare these results to those from their present-day counterparts. Samples will also be obtained from collections of pertinent museums worldwide. Assessing the bioavailable strontium for the Nile River Valley will also rely on synthesizing existing strontium isotope data obtained by both PIs from ~250 specimens, which consist of both archaeological human and faunal samples investigated from Egyptian (Memphis, Qurneh) and Nubian (Shellal, C-Group, Pharaonic, Amara West, Tombos, Kerma) sites. These combined results will help to characterize the isotope variability and better understand human mobility in this region, which is rich with sociopolitical transitions and contact between groups. The results obtained from this project will help elucidate any input or influence of Holocene climate change within the Nile River Valley for the past ~4,000 years. By comparing archaeological or paleo-strontium isotope signatures of faunal samples to their present-day counterparts, our study will provide a better understanding of aeolian (wind-driven) contribution, if any, within the Nile River Valley. The proposed research will have major implications for archaeologists conducting isotope-based investigations of ancient migrations around the globe since climate change is a phenomenon that has occurred throughout Earth's history. For the Nile River Valley, this has involved a drying of the African Humid Period, which have taken place in other regions of our planet.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.