Dynamic Phosphorus Interactions at Soil Mineral-Organic Carbon Interfaces: A Critical Review

Phosphorus (P) is a nonrenewable macronutrient essential for agriculture, yet its availability is often constrained by the formation of mineral-P associations (MPAs) at soil-mineral interfaces. Soil organic carbon (SOC), however, can dynamically transform these MPAs, mobilizing the associated P. This critical review synthesizes the interface processes and mechanisms governing the formation and transformation of MPAs, linking them to farmland P availability. We first outline the specific characteristics of minerals and P phases that lead to the formation of MPAs via adsorption and precipitation. We then introduce a novel conceptual framework in which SOC drives the transformation of MPAs through desorption and dissolution. This framework emphasizes how the specific reactive SOC compounds target mineral-associated P (MAP), with efficacy contingent on MPA inherent properties. We propose a trade-off between the formation and transformation dynamics of MPAs, which governs the legacy P pool and its varying availability. A holistic understanding of these dynamic interactions operating at mineral-organic carbon interfaces will enhance predictions of long-term P fertility and inform the development of innovative SOC-based P management strategies for sustainable agriculture and environment.