Evaluating the Influence of Salinity on Lipid D/H Fractionation in Saline Lakes

评估盐度对盐湖中脂质 D/H 分离的影响

• 批准号: 0745982
• 负责人: Julian Sachs
• 金额: --
• 依托单位: University of Washington
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-10-01 至 2011-09-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0745982&HistoricalAwards=false
• 关键词: Evaluating; Influence; Salinity; Lipid; Fractionation

Salinity variations in the geologic past are difficult to reconstruct, yet important for understanding climate, ocean circulation, evolutionary biology, and carbon storage in the geologic record. In an effort to develop a new indicator of water salinity we will build on recent experimental results indicating that hydrogen isotope fractionation in algal lipids decreases as salinity increases.Intellectual Merit: Motivated by a recent report by Schouten et al. (2006) that salinity altered hydrogen isotope fractionation in lipids from cultured coccolithophorid algae, and the prospect this finding raises for paleosalinity and paleohydrologic reconstructions, investigators propose to test the generality of a salinity influence on lipid D/H fractionation in a variety of algal, microbial and archaeal lipids in a wide diversity of natural saline systems with salinities between 0.4 - 277 ppt. Their initial results from Christmas Island and the Chesapeake Bay support the hypothesis of Schouten et al. (2006) that D/H fractionation in algal and microbial lipids decreases with increasing salinity. At Christmas Island they find a strong inverse correlation between salinity and lipid D/H fractionation in several algal and bacterial biomarkers and total lipid extracts over the salinity range 17 - 149 ppt . In the Chesapeake Bay they observe a strong inverse relationship between salinity and D/H fractionation in the dinoflagellate lipid dinosterol at salinities between 8 - 31 ppt.The proposed study will use water, particulate and surface sediment samples from 39 globally dispersed saline basins in Canada, the USA, Bolivia, Israel, South Africa, Kazhakstan, and the Galapagos Islands. This highly diverse set of lakes was chosen to span the widest possible range of salinities, limnologies, water chemistries, and climates. They will measure the δD values of several different lipid biomarkers from algae (e.g., dinosterol, highly branched isoprenoid alkenes, fucoxanthin, botryococcenes), bacteria (e.g., diploptene, hopanoids, bacteriochlorophyll a-e) and archaea (glycerol-dialkyl-glycerol-tetraethers) in suspended particles and surface sediments in each lake, and compare those values to the δD values of lake water. They possess all samples for this study.Broader Impacts: This project will support a female graduate student and facilitate the education of undergraduate and high school students in environmental research. Of 11 lab members, 5 are women, 4 are undergraduates and 1 is in high school. Two undergraduates, along with the PI, conducted the fieldwork to collect the saline lake samples for this project in June 2007. Their website describing their research receives over 700 hits per day. And the PI has been a science judge in 6 national high school science competitions during the last 8 years. These activities will continue to expose students and the public to cutting-edge environmental research.

地质过去的盐度变化很难重建，但对于理解气候，海洋循环，进化生物学和地质记录中的碳存储很重要。为了开发一种新的水盐度指标，我们将基于最近的实验结果，表明藻类脂质中的氢同位素分馏随着盐度的增加而降低。智能优点：Schouten等人最近的一份报告。 (2006) that salinity altered hydrogen isotope fractionation in lipids from cultured coccolithophorid algae, and the prospect this finding raises for paleosalinity and paleohydrologic reconstructions, investigators propose to test the generality of a salinity influence on lipid D/H fractionation in a variety of algal, microbial and archaeal lipids in a wide diversity of natural saline systems with salinities between 0.4-277 ppt。 他们的最初结果来自圣诞节岛和切萨皮克湾，支持Schouten等人的假设。 （2006）藻类和微生物脂质中的D/H分馏随盐度的增加而降低。在圣诞节岛上，他们发现几种藻类和细菌生物标志物的盐度与脂质D/h分馏之间存在很强的反相关性，以及盐度范围内的总脂质提取物17-149 ppt。他们在切萨皮克湾（Chesapeake Bay）中观察到盐酸与D/H分馏之间的牢固的反比关系，在8-31 ppt之间的盐度为盐度。拟议的研究将使用来自加拿大加拿大，美国，美国玻利维亚岛，以色列，南非，岛上的39个全球分散的盐水盆地的水，颗粒和颗粒物和表面沉积物样品，该储物均分散。选择了这套高度多样化的湖泊，以跨越最广泛的盐分，羊水，水化学和气候。 They will measure the δD values of several different lipid biomarkers from algae (e.g., dinosterol, highly branched isoprenoid alkenes, fucoxanthin, botryococcenes), bacteria (e.g., diploptene, hopanoids, bacteriochlorophyll a-e) and archaea (glycerol-dialkyl-glycerol-tetraethers) in每个湖泊中的悬浮颗粒和表面沉积物，并将这些值与湖水的值进行比较。他们拥有这项研究的所有样本。Broader的影响：该项目将支持女性研究生，并促进本科生和高中生在环境研究方面的教育。在11名实验室成员中，有5名是本科生，有1名在高中。两名本科生与PI一起进行了实地调查，以收集2007年6月的该项目的盐湖样本。他们的网站描述他们的研究每天收到700多次命中。在过去的8年中，PI一直是6个国家高中科学比赛的科学法官。这些活动将继续使学生和公众接受尖端的环境研究。