Based on the diverse topography and geomorphology and the complex mechanism of soil erosion in the hilly area of central Hunan Province

China

nine runoff plots with different soil and water conservation measures in three runoff fields of Jingtou (yellow soil)

Qiubo (purple soil) and Lianhe (red soil) were selected to explore the effects of different erosive rainfall patterns

soil types and soil and water conservation measures on runoff and sediment transport on slopes. The results showed that the annual runoff and sediment yield decreased as the following sequence:red soil > purple soil > yellow soil under the condition of similar annual rainfall. The runoff reduction effect in each runoff plot was little

but the sediment reduction was effective. Especially

the grassland measures in yellow soil

water conservation forest in purple soil

and fruit-forest and grassland measures in red soil had obvious sediment reduction effects

and their annual reduction rates were 87.89%

55.88%

37.99% and 41.07%

respectively. The heavy intensity

short duration

low rainfall and high frequency rainfall accounted for more than 50% of the erosive rainfall events in each runoff plot. It was also the dominant rain type of the runoff and sediment yield in the runoff plots of yellow and red soils

as well as the dominant rain type of the sediment yield in purple soil. The moderate intensity

long duration

high precipitation and low frequency rainfall caused the largest runoff and sediment yield in each single rainfall event in all runoff plots. These results could be of great significance for improving the relevant theories of soil erosion

and provide important guidance and theoretical value for the development of regional soil and water conservation.