Soil health as nonequilibrium flow: Bridging a persistent conceptual‐to‐computational inconsistency

Abstract Soil health concepts emphasize soil aggregation and structure as central indicators of healthy, functioning soils, yet this emphasis carries an implicit acknowledgment rarely made explicit in models: aggregated soils exhibit nonequilibrium water flow behaviors through preferential pathways. Despite recognition of preferential flows, dating to 1864, and extensive development of nonequilibrium modeling frameworks (e.g., dual‐porosity, dual‐permeability, and multi‐region models), large‐scale modeling persistently relies on uniform, equilibrium flow assumptions. The soil science community possesses the theoretical knowledge and mathematical tools to describe nonequilibrium flows, yet practical barriers limit integration into soil health assessments. Bridging this gap requires developing practical parameter estimation protocols, augmenting existing soil‐health datasets with nonequilibrium flow characteristics, conducting intercomparison studies, and fostering collaboration between experimentalists and modelers. Evolving beyond static indicators toward mechanistic, process‐based dynamics may allow soil health concepts to become internally consistent with the inherent nonequilibrium nature of aggregated soils. Core Ideas Soil health emphasizes aggregation, yet aggregated soils inherently exhibit nonequilibrium flow. Large‐scale models still use equilibrium assumptions despite a century of nonequilibrium flow knowledge. Parameterization barriers prevent implementing nonequilibrium models at field and landscape scales. Bridging this gap requires practical protocols and recognizing soil health as nonequilibrium processes.