*3.2. Estimation of the Infiltration Model Parameters*

The infiltration rates under the various rainfall intensities on the bare soil were used to fit the four models. The values of each parameter were regressed; these are listed in Table 2. As shown, the S·M parameter in the GAML model was negative (equal to −0.572), which was an invalid value. Therefore, the other three models were used for the infiltration estimation of the black soil, but not the GAML model. The determination coefficient *R*<sup>2</sup> was approximately 0.5, and the regression results passed the significance test at the *p* = 0.01 level.


**Table 2.** The fitted parameters of different infiltration models.

*3.3. Cumulative Infiltration Amounts for the Residue-Covered Black Soil under Various Rainfall Events*

The cumulative infiltration amounts of the residue cover on the black soil under different rainfall events are shown in Figure 4. It was indicated that the residue cover tillage was effective at promoting the infiltration of the black soil and delaying the runoff generation. Under the 30 mm/h scenario, the precipitation nearly seeped into the soil when the residue cover was more than 55%, which proved that the tillage was effective under the relatively small rainfall intensity events. The infiltration amounts did not show that the higher the residue coverages were, the higher the infiltration amounts were. The infiltration amounts under 35% residue cover were less than under 15% residue cover. This result might have been due to the fixed runoff flow path, which could have promoted runoff generation [30].

**Figure 4.** Cumulative infiltration amounts under various rainfall events.
