The measurement and use of bismuth-210 as a tracer of particle flux in aquatic systems

Bismuth-210 作为水生系统颗粒通量示踪剂的测量和使用

基本信息

批准号：
1639865
负责人：
James Waples
金额：
$ 8.37万
依托单位：
University of Wisconsin-Milwaukee
依托单位国家：
美国
项目类别：
Standard Grant
财政年份：
2016
资助国家：
美国
起止时间：
2016-07-01 至 2019-06-30
项目状态：
已结题

来源：
https://www.nsf.gov/awardsearch/showAward?AWD_ID=1639865&HistoricalAwards=false
关键词：
measurement use bismuth 210 tracer

项目摘要

Naturally occurring radioactive nuclides provide invaluable "clocks" with which to investigate a wide range of processes in earth and environmental sciences. Nuclides with shorter half-lives are well suited to studying rapid processes, but are often present at very low concentrations and are particularly difficult to measure. The goal of this Early Concept Grant for Exploratory Research (EAGER) is to develop and demonstrate a new analytical method for measuring bismuth-210 (half life, 5 days) in lake water, seawater, and associated particles. Because bismuth tends to become associated with particles more than its parent isotope lead-210 (half life, 22 years), the bismuth-210/lead-210 daughter/parent pair can potentially be used to investigate very short time-scale processes associated with particle (sediment) formation and cycling in lakes and the coastal ocean. Knowledge about such processes is important to understanding carbon and nutrient cycling in these productive and dynamic areas. The specific goals of this exploratory project are to 1) demonstrate an improved method for measuring the lead-210/bismuth-210/polonium-210 trio in aquatic system samples; 2) measure lead-210/bismuth-210/polonium-210 in Lake Michigan; and 3) explore the feasibility of using bismuth-210/lead-210 disequilibrium as a proxy for particle flux. The project would support an undergraduate student researcher for the summer.

天然存在的放射性核素提供了可见的“时钟”，可研究地球和环境科学中广泛的过程。半衰期较短的核素非常适合研究快速过程，但通常以非常低的浓度存在，并且特别难以测量。探索性研究的早期概念赠款的目的是开发并展示一种在湖水，海水和相关颗粒中测量β-210（半寿命，5天）的新分析方法。由于比其父母同位素铅-210（半寿命，22年）倾向于与颗粒相关联，因此可能会使用Bismuth-210/Lead-210的女儿/父对来研究与颗粒（沉积物）形成相关的非常短的时间尺度过程，以及湖泊和沿海海洋中的颗粒（沉积物）形成和循环。关于此类过程的知识对于理解这些生产和动态领域中的碳和营养循环很重要。该探索性项目的具体目标是1）展示了一种改进的方法，用于测量水生系统样品中的Lead-210/Bismuth-210/Polonium-210三重奏； 2）密歇根湖的LEAD-210/BISMUTH-210/POLONIUM-210； 3）探索使用BiSMUTH-210/LEAD-210不平衡作为粒子通量的代理的可行性。该项目将支持夏季的本科生研究人员。