Abstract：In the spring, runoff process on the freeze-thaw slope is different with that on the non-freeze-thaw slope, since the former contains thawed layer and frozen layer. Planosol, chernozem, brown and cinnamon soil in northeastern China were selected as research objects, and the indoor rainfall simulation was carried out to study the rainfall runoff duration characteristics with incompletely thawed layer. The results showed that: the initial soil moisture was the most important factor affecting runoff duration, and the runoff duration was significantly shortened with the increase of the initial soil moisture, especially for planosol. The runoff duration was a logarithmic function of soil moisture content. The rainfall intensity and initial thaw depth did not significantly affect rainfall runoff duration. An exponential function was proposed to express the rainfall runoff duration by multiple regression. The longer the rainfall runoff duration lasted, the earlier the peak erosion time appeared. The erosion of planosol, chernozem and brown soil was negatively correlated with the runoff duration.
2013, Vol. 11 
