Interactions of Phosphate and Mineral-Associated Organic Carbon in Soils in Relation to Long-Term Phosphorus Fertilization

Summary

Understanding the interaction between phosphate (PO₄) and mineral-associated organic carbon (MOC) in soils is of great importance on maintaining or enhancing soil fertility for plant growth while mitigating climate change and eutrophication. However, due to the compositional complexity of soil organic carbon (SOC) and its inherent heterogeneity, as well as the variation in soil conditions, so far, it lacks a quantitative understanding and ability to model the magnitude of this interaction. To bridge this knowledge gap, this thesis integrates insights from well-defined synthetic systems to soil profiles and field scales. Through laboratory experiments and advanced surface complexation modeling, we aim to get a deeper comprehension of the underlying mechanisms that govern the interactions of PO₄ and SOC when binding to the mineral surfaces of soils, particularly in relation to phosphorus fertilization.