Selecting Hengnan County as the experimental area

runoff plots with the same slope and the same cropping pattern were set up

and the control experiments of different soil and water conservation measures were carried out. We studied the soil erosion modulus of sloping farmland and the benefits of soil and water conservation measures through observing and analyzing the annual rainfall runoff and sediment. The results showed that：(1) In 2016

19 rainfalls with runoff were observed

and the rainfall was 1 145 mm

which was belonged to normal rainfall year; (2) The soil erosion modulus of bare slope without any protective measures was 4 450.57 t/(km2?a)

reaching moderate erosion; (3) Compared with the bare slope

farmland had the effect of soil and water conservation

and different measures had significant difference in reducing runoff and sediment yield. Water conservation effect (decrease ratio of annual surface runoff) from large to small listed in the order of stone dike terraces (85.07%)＞slope terraces (81.50%)＞earth dike terraces (64.57%)＞hedgerow (57.96%)＞slope farming (37.49%). Soil conservation effect (decrease ratio of annual sediment yield) followed the order of stone dike terrace (98.74%)＞slope terrace (98.66%)＞earth dike terrace (97.39%)＞hedgerow (86.16%)＞slope farming (61.98%). Stone dike terrace and slope terrace showed better effect in soil and water conservation. In this study

the background value of soil erosion was observed accurately

and the benefits of the main soil and water conservation measures were evaluated quantitatively.