The capability of soil for carbon (C) stabilization determines if soil is a C source or sink. The adsorption of organic C to soil mineral surfaces is a key mechanism for long term C stabilization. In agricultural production, soil phosphorous (P) accumulation, as a result of P fertilization, can enhance the competition of phosphorus with organic matter for adsorption to mineral surfaces, and consequently, has the risk to reduce the amount of adsorptive protected organic C. The current project aims to investigate the significance and mechanism of P fertilization effect on soil C stabilization, focusing on the interactions between phosphate ions and natural organic matter at the mineral surface. Methodologies of experimental study and chemical modelling will be combined in this research.