Collaborative Research: Alkenone-specific Hydrogen Isotopic Assessment of Surface Water Salinity During the Black Sea's Holocene Evolution

摘要（0601910）合作研究：实验室验证烯酮特定的氢同位素组成作为一个强大的，定量代理古盐度测定F.G. Prahl（俄勒冈州州立大学）和B.N.波普（夏威夷）过去海洋盐度和温度的知识对于评估诸如表层水循环和深水形成等基本海洋学过程至关重要。这些过程是地球表面热量重新分布的组成部分，因此也是全球气候变化动态的组成部分。在该项目中，PI建议对一种新的古盐度指标进行校准实验，该指标是由浮游植物Emiliania huxleyi和Isochrysis galbana生物合成的独特生物标志物分子的化合物特定氢同位素（D/H）组成。 核心假设是，这些生物标志物的D/H基本上由源生物生长的水的同位素组成控制。在这里，将分析在不同的实验室控制的实验条件下的分批培养实验中生物合成的化合物的D/H，以评估D/H值可以作为生理生长因素的函数而变化的程度，所述生理生长因素例如营养物和光的可用性和实际的盐度变化以及物种之间的变化。从这个代理的实验室结果，然后将被用来检查黑海的全新世演变，以确定是否盐度阈值影响浮游植物生态的表面沃茨，并造成了充分记录的中全新世转移黑海沉积物的沉积特征。这些实验的结果将直接纳入课堂教学，使前沿，专题信息转移到本科科学和非科学专业，并在海洋学和地质学专业的研究生。来自俄勒冈州州立大学荣誉学院的一名本科生将从这个项目中受益。夏威夷大学是指定的EPSCoR机构和联邦政府承认的少数民族服务机构，因此，来自代表性不足群体的学生很可能从这项研究结果产生的教育活动中受益。

Abstract (0601910)COLLABORATIVE RESEARCH: Laboratory Validation of Alkenone-Specific Hydrogen Isotopic Composition as a Robust, Quantitative Proxy for Paleosalinity DeterminationF.G. Prahl (Oregon State University) and B.N. Popp (University of Hawaii)Knowledge of past ocean salinity and temperature is essential for assessment of basic oceanographic processes such as surface water circulation and deep water formation. Such processes are integral to the redistribution of heat on the Earths surface and consequently to the dynamics of global climate change. In this project, the PIs propose to conduct calibration experiments on a novel paleosalinity indicator, the compound specific hydrogen isotopic (D/H) composition of unique biomarker molecules that are biosynthesized by the phytoplankton species Emiliania huxleyi and Isochrysis galbana. The central hypothesis is that the D/H of such biomarkers is controlled fundamentally by the isotopic composition of the water in which the source organism grows. Here, the D/H of compounds biosynthesized in batch culture experiments under varying laboratory-controlled experimental conditions will be analyzed in order to evaluate the extent that D/H values can vary as a function of physiological growth factors such as nutrient and light availability and actual salinity change as well as between species. The laboratory results from this proxy will then be used to examine the Holocene evolution of the Black Sea to determine whether a salinity threshold impacted phytoplankton ecology of surface waters and caused the well-documented mid-Holocene shift in the depositional characteristics of Black Sea sediments. Results of these experiments will be integrated directly into classroom teaching, allowing transfer of cutting edge, topical information to undergraduate science and non-science majors and to graduate students specializing in oceanography and geology. An undergraduate student from the Honors College at Oregon State University will benefit educationally from this project. The University of Hawaii is a designated EPSCoR institution and a federally recognized minority-serving institution, thus students from underrepresented groups are likely to be benefit from education activities stemming from the results of this research.