Spatial distribution of runoff and sediment in the vertical belts of soil erosion chain in loess region of hilly and gully

Spatial distribution of runoff and sediment in the vertical belt sections of soil erosion chain is studied by the simulated rainfall examination on block diagram combined with multi-slope sections.The results show that the runoff increase from the upper slope to lower one.The runoff per unit area and the unit time increases in order of the upper hillslope,the middle hillslope,the lower hillslope and the gully slope.Also,different the erosion patterns develop well on the hillslope with rainfall intensity of 90.2 mm/h and rill erosion extends from bottom of the slope to the middle and the upper hillslopes.Rill erosion,in contrast,only occurs in the lower hillslope and gully slope with rainfall intensity of 60.5mm/h,and gully erosion do not develop with rainfall intensity of 29.7mm/h.Due to the effect of runoff from the upper slope,sediment yields of hillslope and gully slope have increased by 20.2%～63.5% and 42.9%～74.5% respectively.