Effects of rainfall intensity and land use on rainfall runoff and storage in Loess hilly region.

By using rainfall simulator,an experiment was conducted to quantitatively study the rainfall runoff and storage in Loess Hilly region under effects of different rainfall intensity and land use. Rainfall intensity had significant effects on the rainfall runoff,and there was a negative exponential relationship between rainfall intensity and runoff coefficient. Rainfall intensity also had significant effects on rainfall storage. When the rainfall intensity was 1.97,2.14,2.46,2.94,and 3.75 mm·min-1,the average storage coefficient of land use was 0.73,0.62,0.58,0.55,and 0.44,respectively. The average runoff coefficient of different rainfall intensities was in the order of forestlandcultivated landartificial grasslandnatural grassland,and the runoff storage coefficient of forestland,natural grassland,artificial grassland,and cultivated land was 0.44,0.68,0.66,and 0.55,respectively. In the ecologically fragile Loess hilly region,grassland showed good effects in water and soil conservation,and the canopy-,shrub-,and litter layers on forestland had significant effects in intercepting,retarding,and reducing rainfall.