[Objective] To determine the utilization of phosphorus in slope ecological rehabilitation substrate in order to provide theoretical basis for optimizing substrate formulation.[Methods] Adsorption-desorption characteristics of phosphorus in five types of slope ecological rehabilitation substrates were studied via constant temperature shaking culture. Then

the adsorption-desorption capacity and loss risk of the five substrates were compared with factor analysis.[Results] The maximum adsorption capacity(Qm)

maximum buffering capacity(MBC) and phosphorus sorption index(PSI) have shown that the phosphorus fixation capacity of the five substrates was in an order of the natural secondary forest > the external-soil spray seeding > the thick layer substrate > the framed beams soil covering > the vegetation-compatible concrete. It showed that Qm had positive correlation with clay content

while it had negative correlation with organic matter content and pH value. The desorption ability of the five types of substrates was the vegetation-compatible concrete > the framed beams soil covering > thick layer substrate > the external-soil spray seeding > the natural secondary forest. The average desorption rate had significantly positive correlation

and it also had positive correlation with organic matter content. The negative correlation was found between the average desorption rate and clay content. This study showed that Qm

MBC

PSI

the average desorption rate and easy desorption phosphorus(RDP) could best reflect the phosphorus loss risk of five different substrates. It showed that from high to low

the order of the phosphorus loss risk was the vegetation-compatible concrete

the framed beams soil covering

the external-soil spray seeding

thick layer substrate and the natural secondary forest.[Conclusion] The natural secondary forest has the highest conservation capacity of phosphorus in the five ecological rehabilitation engineering ways

while the vegetation-compatible concrete has the lowest. In slope ecological rehabilitation engineering

the proportion of clay content should be increased and the dosage of cement should be decreased

or buffering material be added into substrate

so that the substrate can have a stronger phosphorus adsorption capacity

the larger phosphorus storage

the smaller phosphorus loss risk. Thus

the utilization ratio of phosphorus can be improved and the supplying ability can last longer.