Taking the grassland

the Xanthoceras sorbifolia

the Hippophae rhamnoides and the Caragana korshinskii shrub in Lijiabao

the hilly-gully region in the Loess Plateau

as the research objects

the field sampling and the indoor analysis were used to study the soil physical characteristics and infiltration characteristics under four vegetation types. The results showed that with the increase of soil depth

soil bulk density increased generally

while soil porosity and aeration decreased. In the four vegetation types

the soil bulk density of grassland was the largest

with the smallest porosity and aeration

while the soil bulk density of Caragana korshinskii shrub soil was the smallest

with the highest porosity and aeration. The physical characteristics of soil water were the largest in Caragana korshinskii

the following was in Xanthoceras sorbifolia and Hippophae rhamnoides

and the lowest in grassland. The maximum water holding capacity

capillary holding capacity

minimum water holding capacity

maximum water storage capacity and drainage capacity of 0-40 cm soil layers in Caragana korshinskii shrub were 23.00%

22.51%

15.02%

12.76% and 61.28% respectively higher than those in grassland

and the variance analysis showed significant difference. The logarithmic relationships were found for the soil moisture infiltration processed under the four vegetation types

the R2 of soil permeability coefficient were between 0.937 9 and 0.986 9

and the F test reached the extremely significant level (P<0.001). The infiltration rate and water conservation capacity of Caragana korshinskii shrub were significantly higher than those of grassland

which could improve soil physical characteristics and increase the construction of Caragana korshinskii forest.