REU: Rare Earth Tracer Techniques for Larval Dispersal

我们在了解海洋系统中幼虫的扩散和招募过程方面取得进展的一个主要限制是我们无法跟踪海洋中幼虫的运动和命运。莱文博士将研究利用稀土元素在该领域标记无脊椎动物幼虫和无生命（被动）颗粒的技术发展。稀土元素是极好的示踪剂，因为它们在自然界中以极低的背景水平存在，并且在引入现场时是惰性的，但当受到中子激活时，它们变得具有高放射性，并且在纳米到皮克级水平上可以检测到。与其他示踪剂相比，该示踪剂的优点是在浮游生物或组织样品中进行标记检测所需的时间短，人力少，并且与中子活化分析相关的灵敏度和准确性高。该研究将开发双壳类、甲壳类和多毛类幼虫的掺入技术，评估标签持久性和行为影响，并将稀土掺入与感兴趣的幼虫相当的下落速度的被动颗粒中。

A major limitation to our progress in understanding of larval dispersal and recruitment processes in marine systems is our inability to track the movements and fate of larvae in the ocean. Dr. Levin will investigate the development of techniques for use of rare earth elements to label invertebrate larvae and inanimate (passive) particles in the field. Rare earth elements make excellent tracers because they occur at extremely low background levels in nature and are inert when introduced into the field, but become highly radioactive and are detectable at nano-to picogram levels when subjected to neutron activation. Advantages of this tracer over others are the short time and minimal manpower required for label detection in plankton or tissue samples, and the high degree of sensitivity and accuracy associated with neutron activation analysis. The research will develop incorporation techniques for bivalve, crustacean and polychaete larvae, assess label persistence and behavioral effects, and incorporate rare earths into passive particles with fall velocities comparable to the larvae of interest.