Abstract:Snowmelt erosion is an important part of soil and water loss in seasonal snow cover area. It is important for preventing and controlling erosion gully to understand the effect of snowmelt on gully development. Based on the field observation and measurement, snowmelt erosion processes and rill erosion morphology of gully slope were analyzed in the northeast black soil area, and the prevention and control effect of soil and water conservation measures on snowmelt erosion was investigated. The results showed that there was no runoff in G2, and the runoff rate and sediment concentration of G1 and G3 in middle stage of snowmelt period was greater than those in last stage and initial stage of snowmelt. The daily dynamic changes of runoff rate and sediment concentration were both increased first then decreased. During the snowmelt period, for the three gullies, mean rill width was ranged from 6.7 to 9.4 cm, mean rill depth was ranged from 3.3 to 4.3 cm. The number of rill, rill density, degree of rill dissection, rill tortuosity complexity and average rill erosion depth on sunny slope were all greater than those on shady slope, which indicated that the degree of rupture and rill erosion on sunny slope was greater than that on shady slope. The rill was dominated by type of wide-shallow, and the ratio of width to depth was ranged form 1.91 to 2.18. Effect of soil and water conservation measures was obvious during snowmelt period. The benefits of soil and water conservation measures on water and sediment blocking in erosion gully G2 was 100%, and for G1 and G3, most of the sediment eroded by snowmelt was also deposited in the gully.