Abstract In Earth's surface environment, calcium (Ca) is an important mobile metal that is actively and passively transported in solution and within organic and mineral phases, being cycled and recycled during various biogeochemical processes. With the development of modern mass spectrometric techniques small variations in the stable and radiogenic isotopic compositions of Ca can be measured, revealing insight in these complex biogeochemical cycles and tracing and quantifying components across a range of spatial and temporal scales similar to other more routine isotope systems. More than three decades of work reveal systematic variations in the partitioning of Ca isotopes due to both abiotic and biological processes. An overview of processes that fractionate Ca isotopes at local, regional, and global scales is outlined here. We present detailed examples of instances in which Ca isotopes have provided unique insight into the functioning of Earth surface processes and the cycling of Ca at multiple scales. Future studies should target questions for which Ca isotopic analysis provide unique insight and, when combined with other isotope and trace element multi-proxy studies, better constrain the system of interest. At the same time, we challenge the scientific community to explore new frontiers including polar regions and other extreme environments.

中文翻译：

---

使用钙同位素阐明局部、区域和全球尺度的现代地球化学循环

摘要 在地球表面环境中，钙（Ca）是一种重要的移动金属，在溶液中以及有机相和矿物相中主动和被动运输，在各种生物地球化学过程中被循环和再循环。随着现代质谱技术的发展，可以测量 Ca 的稳定和放射性同位素组成的微小变化，揭示这些复杂的生物地球化学循环的洞察力，并在类似于其他更常规同位素系统的一系列空间和时间尺度上追踪和量化成分. 超过三年的工作揭示了由于非生物和生物过程导致的 Ca 同位素分配的系统变化。此处概述了在局部、区域和全球范围内分馏 Ca 同位素的过程。我们提供了详细的实例，其中 Ca 同位素为地球表面过程的功能和 Ca 在多个尺度的循环提供了独特的见解。未来的研究应该针对 Ca 同位素分析提供独特见解的问题，并且当与其他同位素和微量元素多代理研究相结合时，可以更好地约束感兴趣的系统。同时，我们挑战科学界探索包括极地和其他极端环境在内的新领域。当与其他同位素和微量元素多代理研究相结合时，可以更好地约束感兴趣的系统。同时，我们挑战科学界探索包括极地和其他极端环境在内的新领域。当与其他同位素和微量元素多代理研究相结合时，可以更好地约束感兴趣的系统。同时，我们挑战科学界探索包括极地和其他极端环境在内的新领域。