Rill Erosion Characteristics on Slope Farmland of Horizontal Ridge Tillage during Snow-melting Period in Black Soil Region of Northeast China
Rill development was different between thawing and rainfall periods,which was caused by the effects of snowmelt runoff,freezing-thawing action and incomplete thawing layer on soil.Based on the field observation,the study analyzed rill erosion morphology and its spatial distribution on slope land with horizontal ridge tillage in typical black soil area during snow melting period.The results showed that the rill on slope land with horizontal ridge tillage caused by snowmelt erosion were three types rill along the ridge,rill across the ridge and rill of complex morphology.Among the three types of rill,the average length and width of rill along the ridge were larger but the depth was less than that of the other two types.Length variation and the average length of rill across the ridge were the smallest but the depth was the largest.The average length of rill of complex morphology was the largest but the width was the smallest.The largest rill erosion mainly occurred in the lower position of uniform slope,accounting for 85％ of the whole slope,and the types mainly included rill along the ridge and rill across the ridge.Low-lying area in the middle position of slope with fluctuation had the largest rill erosion amount,accounting for 64％ of the whole slope,and rill erosion occurred in all the three types.On slope farmland of horizontal ridge tillage,changes of micro-topography and incompletely thawing layer affected rill morphology during thawing period,and rill distribution was mainly affected by slope topography and snowmelt runoff.
Rill erosionSnowmelt runoffFreezing and thawing, Black soil hillslope
NETL
NSTL
万方数据
维普
