Abstract:In order to study the regulation mechanism of intercropping on soil erosion, the rainfall infiltration rules of maize-potato intercropping and ridging under different rainfall intensities (40 and 80 mm/h) and slope gradients (10° and 15°) were evaluated by stimulated rainfall method. The results suggested that:(1) The infiltration terminal time of maize-potato intercropping (IC) was later than that of maize sole crop (MC) under the same slope and rainfall condition during the growth period, and the difference of infiltration start time was not significant. During the experimental periods, the infiltration amount of IC was significantly higher than that of MC (P<0.01), but not significantly different from that of potato sole crop (PC) (P>0.05). During the growth period, the infiltration amount of IC were 25.75%~69.07% and 21.76%~50.95% higher than that of MC under the rainfall intensities of 40 mm/h and 80 mm/h, respectively, The infiltration rate of IC was higher than that of MC under the same rainfall intensity, but there was no significant difference between IC and PC. (2) The infiltration amount of intercropping with high ridging (IC+HR) was significantly higher than those of intercropping with low ridging (IC+LR) (P>0.05), maize sole crop with high ridging (MC+HR) (P<0.01) and maize sole crop with low ridging (MC+LR) (P<0.01). Under the rainfall intensity of 40 mm/h, infiltration amount of IC+LR, IC+HR and MC+HR was 10.10%~28.14%, 25.75%~65.96% and 41.59%~75.46% higher than that of MC+LR, respectively, while under the rainfall intensity of 80 mm/h, the corresponding values were 9.12%~18.03%, 21.76%~44.34% and 36.45%~57.05%, respectively. Thereby, intercropping increased rainfall infiltration and reduced the occurrence of surface runoff, which provided an important reference for understanding the mechanism of soil erosion controlling by crop cultivation. In addition, intercropping with high ridging could effectively increase rainfall infiltration, which was important for guiding regional water resources management and sustainable development of agriculture.