In order to explore the characteristics of soil water conservation function of different vegetation types in the Xarxili Nature Reserve

a total of 13 representative grassland

shrub and forest plots were selected in the reserve area

and soils of different vegetation types were used as experimental materials. Soil water conservation capacity of grassland

shrub and forest was quantitatively analyzed by a combination of field investigation and laboratory tests. The results showed that:(1) With the increasing of soil depth

the soil bulk density of the grassland increased gradually

and the minimum value was 0.69 g/cm3 at 0-10 cm soil layer. The changes of soil water holding capacity and water storage capacity of grassland were consistent

which followed the order of 0-10 cm > 10-20 cm > 20-30 cm. (2) With the increasing of soil depth

the variation of soil bulk density of shrub was quite different

ranging from 0.98 to 1.63 g/cm3

and the minimum value appeared at 0-10 cm soil layer. The water conservation capacity index contents were significantly different in different soil depths (P<0.05)

and the water holding capacity of shrub was generally listed in the order of 0-10 cm > 10-20 cm > 20-30 cm>30-40 cm > 40-50 cm

and the water capacity increased first and then decreased with the increasing of soil depth. (3) There was a significant difference between the hydrophysical properties of forest soil and soil water conservation index (P<0.05). With the increasing of soil depth

the soil bulk density increased gradually

and the minimum value was 0.45 g/cm3 at 0-10 cm soil layer. The water holding capacity of forest soil was mainly 0-10

20-30 and 40-50 cm

accounting for 71.6% of the total water holding capacity

the water storage capacity was relatively small in the water conservation function.