The continuous investigation and experiment on different vegetation in the loess hilly and gully region in past 10 years were conducted. The results indicate that soil moisture content varieties among the artificial grass

the seabuckthorn and the Chinese pine woodland are basic consistence in the long series years

the water resources were 100-140 mm in 1 m soil layer

and the soil was in "dry horizon" stage during growth period. Soil water content in natural grass land was about 40mm higher than artificial grass land in a year

the soil humidity was always in proper and stable level. The woodlands

seabnckthorn and Chinese pine

express the growth condition that are adapte to the weather character. But from the point of hydrological circulation condition

the long time "dry horizon" stage of soil humidity was disadvantage for vegetation growth and ecosystem development. The runoff experiments indicate that the average runoff of artificial grass land and Chinese pine woodland was 1. 45 mm and 1. 27 mm

the runoff coefficient was 0.08 and 0.07; The natural pasture and the seabuckthorn woodland did not produce big runoff during a year. The runoff was also small

and lots of them were clear fluid. Therefore

the managing measures of vegetation instauration should appropriate to its natural restoration and protection

and make greatly use of the runoff resources to add soil humidity

and to develope toward the benefical vegetation growth direction.