In this paper

the artificial simulated rainfall combined with the indoor backfill soil trough was used to study the difference among the characteristics of the runoff and sediment yield in the red soil slopes with different parent meterials: granite

quaternary and red sandstone. Results showed that the order of surface runoff time of the three parent materials was granite＜red sandstone＜quaternary

averaging runoff rates and the total amount of runoff were granite＞red sandstone＞quaternary

where the runoff amount of granite red soil under 45 mm/h rainfall was 1.79～2.47 times of those of red sandstone and quaternary

and the averaging runoff rate was 1.58～2.32 times of those of the latter two. Under the rainfall conditions of 45 mm/h

the sediment concentration of the field was the quaternary＞granite＞red sandstone

while

it was granite＞red sandstone＞quaternar under 135 mm/h. The rain intensity had a greater influence on the sediment yield of red soil slope

and the sediment concentration under 135 mm/h was 8.31～11.32 times of 45 mm/h. As for the runoff composition

the proportion of interflow in runoff was highest in quaternary red soil among the materials

which was about 8%～44% in the two rain intensities. The larger rain intensity

the more obvious effect of the surface confluence

which could reach up to 79%～90% of the total runoff under 135 mm/h. The runoff time of interflow was same as that of the surface runoff: granite＜red sandstone＜quaternary

the interflow of granite red soil was smallest

accounting for only 53%～67% of the quaternary

and even 42%～52% at the peak runoff. After the rainfall

the regression of interflow could be predicted by an exponential function

all the decision coefficients were above 0.82 for all conditions

showing a good predictability.