Abstract: Soil infiltration characteristics in Abies georgei var.smithii forest of Sygara Mountains in Tibet were comprehensively evaluated.Results showed that soil infiltration indicators(initial infiltration rates,steady-state infiltration rates,mean infiltration rates,the total penetration)had the gradually decreasing tendency as the increasing of soil depth in the same altitude.From the different elevations,the four soil infiltration indicators presented the maximum at the altitude of 3 700m,and the minimum at the altitude of 4200m.Through the principal component analysis(PCA),the order of soil infiltration performance was gained,which was 3 900m>3 800>4 200m>4 100m>4 000m>3 700m.The soil infiltration indicators were positively related with soil bulk density,had no relationship with soil moisture content.According to above analysis,the dominant factor equation of soil infiltration was established,which reached extremely significant level.

Key words: soil infiltration, Abies georgei var.Smithii, Sygara Mountains, Tibet