Soil plays a key role in sustaining both human societies and terrestrial ecosystems. As a biogeochemical engine of the Earth's life support system, soil fulfils many crucial functions. . Soil anchors plant roots and serves as a reservoir of essential nutrients. Furthermore, it acts as a natural filtration system for rainwater, safeguarding underground water sources by buffering against waste and pollutants. Besides these practical functions, soil is the largest terrestrial repository of organic carbon , storing more than three times the amount of organic carbon found in vegetation and approximately twice as much as the atmosphere. This has contributed to a recent upsurge in interest in agricultural management strategies that aim to improve carbon storage as well as preserving or improving soil resources for future generations. These include methods such as reduced tillage and regenerative agriculture, as well the adoption of new agrochemical approaches that aim to work with rather than against natural soil biology and structure. All the functions of soil in ecology and agriculture are founded on its inherently complex 3D structure and dynamics. The combination of mineral grains of various sizes, pores fulfilled with water and air, together with organic materials, and living plant roots and microbiome makes soil "the most complex biomaterial on the planet". 9 3D dynamic processes include the flow and transport of water, gases, nutrients and pathogens, as well as the growth of roots, fungi and microbial colonies. Understanding soil as a functional biophysical system therefore requires the ability to image and characterize these 3D structures and processes, at high spatial and temporal resolution.