[Objective] The paper aims to study the characteristics of soil phosphorus adsorption-desorption and its influencing factors under six types of land use

namely rainfed farmland

forest land

orchard

grass land

tea plantations and paddy field in purple hilly area of Eastern Sichuan

in order to provide theoretical support for the risk assessment of phosphorus loss in purple soil under different land use types.[Methods] Soil samples were collected at a depth of 0-20 cm layer from six types of land use in research region

and then soil phosphorus adsorption-desorption parameters were determined according to the culture experiment

and related soil physical and chemical properties were measured. Principal component analysis and twiddle factor analysis methods were used to evaluate the risk of soil phosphorus loss and its main influencing factors.[Results] Soil pH value

organic matter

soil water soluble phosphorus

available phosphorus

total phosphorus

CaCO3 and available Zn were important factors affecting the adsorption of soil phosphorus. The principal component factor analysis showed that the contribution of soil available phosphorus

total phosphorus

CaCO3 and available Zn to purple soil phosphorus adsorption capacity were 86.9%

89.2%

89.4%

96.9%

respectively. According to factor analysis

the four parameters of maximum phosphorus absorption capacity(Qm)

maximum buffering capacity(MBC)

easy absorption of phosphorus(RDP)

intercept value b could be used to forecast the risk of phosphorus loss in purple soil.[Conclusion] Among the six types of land use in the study area

orchard and dry farmland had the higher risk of phosphorus loss

whereas paddy fields and tea garden had the lower risk of phosphorus loss.