Positron-emitting nuclides have long been used as imaging agents in medical science to spatially trace processes non-invasively, allowing for real-time molecular imaging using low tracer concentrations. This ability to non-destructively visualize processes in real time also makes positron imaging uniquely suitable for probing various processes in plants and porous environmental media, such as soils and sediments. Here, we provide an overview of historical and current applications of positron imaging in environmental research. We highlight plant physiological research, where positron imaging has been used extensively to image dynamics of macronutrients, signalling molecules, trace elements, and contaminant metals under various conditions and perturbations. We describe how positron imaging is used in porous soils and sediments to visualize transport, flow, and microbial metabolic processes. We also address the interface between positron imaging and other imaging approaches, and present accompanying chemical analysis of labelled compounds for reviewed topics, highlighting the bridge between positron imaging and complementary techniques across scales. Finally, we discuss possible future applications of positron imaging and its potential as a nexus of interdisciplinary biogeochemical research.

长期以来，正电子发射核素一直被用作医学科学中的显像剂，以无创地对过程进行空间示踪，从而允许使用低示踪剂浓度进行实时分子成像。这种实时无损可视化过程的能力也使正电子成像特别适合探测植物和多孔环境介质（如土壤和沉积物）中的各种过程。在这里，我们概述了正电子成像在环境研究中的历史和当前应用。我们重点介绍植物生理研究，其中正电子成像已被广泛用于对各种条件和扰动下大量营养素、信号分子、微量元素和污染金属的动态成像。我们描述了如何在多孔土壤和沉积物中使用正电子成像来可视化传输，流动和微生物代谢过程。我们还讨论了正电子成像与其他成像方法之间的接口，并针对已审查的主题对标记化合物进行了随附的化学分析，突出了正电子成像与跨尺度互补技术之间的桥梁。最后，我们讨论了正电子成像未来可能的应用及其作为跨学科生物地球化学研究纽带的潜力。