Abstract:Based on the rainfall data from 1989 to 2016 in Suining Soil and Water Conservation Experimental Station, four rainfall patterns were classified,which were rainfall pattern Ⅰ (long duration and light rainfall intensity), rainfall pattern Ⅱ (long duration and moderate rainfall intensity), rainfall pattern Ⅲ (short duration and moderate rainfall intensity) and rainfall pattern IV (short duration and heavy rainfall intensity). Meanwhile, four periods were selected according to the tillage patterns to analyze the yield law of runoff and sediment on sloping farmland. The results showed that:(1) During 1991-1992, contour ridge and furrow treatment closed at both ends was the best pattern to preserve soil and water, and there was no significant difference among the rainfall patterns (P>0.05). The effect of slope furrow ridge treatment on soil and water conservation decreased with the increasing of the angle between ridge and furrow.(2) During 2004-2005, sediment yield of sloping ridge plots was 10~20 times that of cross ridge plots, while runoff yield was 1~3 times, which indicated that the reducing sediment effect of the cross ridge was better than its reducing runoff effect, and the soil and water conservation effect of planting Hemerocallis citrine Baroni was better than that of planting Zea mays. (3) During 2006-2008, planting hedgerow of Leucaena leucocephala disturbed the surface soil of the farmland at the initial stage, therefore the runoff and sediment yields of hedgerow plots were larger than that of the control plots, and there was no significant difference in runoff yield among different rainfall patterns(P>0.05). The sediment yield of Z. mays/Ipomoea batatas and Triticumaestivum plot on the cross slope under rain pattern Ⅱ was significantly higher than that of other rain patterns (P<0.05), which was 4.4~26.7 times that of other rain patterns. (4) During 2013-2016, the hedgerow had been colonized for three years, the soil and water conservation effect of hedgerow plots were better than that of control plots, and the sediment reduction effect was better than runoff reduction effect, and the soil and water conservation effect of Vetiveria zizanioides hedgerow was better than that of L. leucocephala hedgerow. Under rainfall pattern Ⅲ, there was very significant difference in sediment yield among the plots (P<0.01). On the whole, contour ridge and furrow treatment closed at both ends was the best way for soil and water conservation. Hedgerow had obvious effect on reducing sediment yield, but it increased sediment yield at the initial stage, and occupying farmland and affecting machine ploughing were also weak points. Therefore, suitable tillage and cropping patterns should be selected in combination with natural economic conditions.