Looking at Soil as It Is: Evolution of Microscopic Soil Characterization From Kubiëna to Artificial Intelligence

ABSTRACT With this commemorative article in the centennial issue of the Journal of Plant Nutrition and Soil Science , we trace the evolution of microscopic soil characterization over the past 100 years, with a particular focus on German soil science. We acknowledge the groundbreaking work of Walter Kubiëna as the founding father of soil micromorphology and follow a timeline shaped by two soil structure‐related priority programs funded by the German Research Foundation, established in 1957 and 1989. Each program marked a pivotal transition: The former coincided with technical revolutions in the automation of soil thin section production for high‐throughput analyses, the latter with the transition from the analog to the digital era. Today, we are facing another technical revolution brought about by the potential of artificial intelligence. We highlight seminal advancements in techniques, terminology, and research focus—from early soil micromorphology to modern x‐ray computed tomography (x‐ray CT) and correlative microscopy. This retrospective is not just a look back—It is a call forward. By combining past insights with cutting‐edge tools, soil micromorphology is now poised to address modern challenges in soil science, tackling Kubiëna's original vision of soil as a living and dynamic system that can be observed with unprecedented precision and resolution.