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为研究地球和环境科学中的各种过程提供了宝贵的“时钟”。半衰期较短的核素非常适合研究快速过程，但通常浓度非常低，并且特别难以测量。这项探索性研究早期概念资助 (EAGER) 的目标是开发和演示一种新的分析方法，用于测量湖水、海水和相关颗粒中的 bismuth-210（半衰期，5 天）。由于铋往往比其母体同位素铅 210（半衰期，22 年）更容易与粒子相关，因此铋 210/铅 210 子体/母体对可潜在地用于研究与湖泊和沿海海洋中颗粒（沉积物）的形成和循环。有关此类过程的知识对于了解这些生产和动态区域的碳和养分循环非常重要。该探索性项目的具体目标是 1) 展示一种测量水生系统样品中铅 210/铋 210/钋 210 三重奏的改进方法； 2) 测量密歇根湖中的铅-210/铋-210/钋-210； 3) 探索使用 bismuth-210/lead-210 不平衡作为粒子通量代表的可行性。该项目将为一名本科生研究员提供暑期支持。