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Near-surface hydrologic conditions (NHC), including drainage, saturation, and seepage, are key drivers for summer rainfall-induced erosion. Among these, saturation and seepage intensify erosion compared to drainage, with their effects remaining relatively consistent under controlled hydraulic gradients. However, it remains unclear whether the erosive characteristics of NHCs, influenced by freeze-thaw action (FTA) and thawed soil depth (TSD) differ under winter-spring snowmelt erosion compared to summer rainfall-induced erosion. The Mollisol region of Northeast China is highly susceptible to both erosion types, posing a significant threat to agricultural productivity. This study investigates the impact of FTA on the erosive characteristics of NHCs during snowmelt erosion and compares it with summer rainfall-induced erosion. The mechanisms underlying these differences and the influence of FTAs on varying TDS were identified. This study was designed to verify two main hypotheses: (1) FTA could enhance the erosive effects of saturation and seepage by reducing soil effective stress, and (2) NHC's erosive characteristics are TSD-dependent, with saturation and seepage effects being limited when the availability of erodible soil is insufficient. Three NHC conditions (drainage, saturation, and seepage) were tested alongside five TSDs: 1 cm (FS1), 3 cm (FS3), 5 cm (FS5) and 10 cm (FS10), as well as an unfrozen control (10 cm, UFS10). Experiments were conducted on silty clay loam with an 8.75% slope under three meltwater intensities (2, 3 and 4 L/min). Results showed that FTA enhanced the erosive effects of saturation and seepage compared to summer rainfall-induced erosion, by altering pore-water pressure. This effect was most pronounced under FS5 and FS10, where erosion increased with TSD stabilized. The contribution of NHCs to erosion rate reached 51.71% under FS5 and FS10, representing a 902.13% increase compared to UFS10 (5.16%). In contrast, no significant differences in erosion rate across NHCs were observed in FS1 and FS3 (P > 0.05). These findings demonstrate that the erosive effects of NHCs on frozen slopes are strongly TSD-dependent and provide novel insights into the mechanisms of snowmelt erosion.