In order to study the erosion caused by spring snowmelt of slope farmland in Northeast China and the affecting factors

in-situ observation was carried out on a sloping farmland in small watershed in Jixing

Jilin province. The changes of runoff and sediment yield during snowmelt were analyzed

the effects of factors such as snowmelt runoff and soil thawing depth on snowmelt erosion were investigated

and process and change rules snowmelt erosion of sloping farmland were explored. The results showed that

under the meteorological conditions of the average temperature of 0 to 3.8 ℃

spring snowmelt erosion was relatively concentrated

runoff and sediment yield increased first and then decreased. Snowmelt runoff and soil thawing depth were important factors affecting snowmelt erosion. In the early stage

runoff from melting snow increased dramatically

and accounted for 59.15% of the total snow melting period

soil was frozen at the same time. In the middle stage

snowmelt tended to stabilize

surface soil began to thaw

runoff decreased and sediment yield continued to increase

the amount of erosion reached the maximum and accounted for 41.74% of the total erosion. At the end

there was no snow on the slope

and the depth of soil thawing increased

runoff decreased and sediment concentration reached the maximum (8.00 kg/m3). Spring snowmelt erosion of sloping farmland was affected by the topographic changes of ridge area and catchment basin

runoff and sediment yield showed a strong regularity. When their peak frequency was consistent

runoff sediment showed an “8”cycle lag relation

but showed a compound cycle lag relationship when their peak frequency was inconsistent.