Splash Erosion and Selective Characteristics of Aggregate for Typical Black Soil Under Artificial Rainfall Condition

An experiment was conducted to study the splash erosion and selective characteristics of aggregates for the typical black soil under artificial rainfall condition in terms of splash erosion amount,fraction of water-stable aggregate,mean weight diameter(MWD) of aggregate,aggregate enrichment ratio(ER) and other indexes by taking the topsoil in a sloping farmland in the typical black soil zone as the study object.Results showed that the splash erosion amount and net transport amount for cylindrical collectors(upslope,downslope) from different collecting regions exhibited an significant correlation in exponential function with splash distance,and R2 values ranged from 0.834 4 to 0.991 1.Aggregate enrichment ratios of the soil changed between 0.00 and 1.79,and the critical particle size fraction of enrichment and depletion for splash erosion was 1.0 mm.Fraction of water stable aggregate in the splashed fragment shows that the proportion of small size fraction increased with increasing splash distance in horizontal space,and 2～5 mm aggregates appeared only in 0～5 cm on upslope and 0～10 cm on downslope,1～2 mm aggregates mostly distributed on upslope with a largest distributional distance of only 28 cm.MWD values ranged from 0.32 mm to 0.80 mm and declined with increasing splash distance,and MWD in 10～17 cm on downslope was significant different from that in 0~10 cm and 17～40 cm.The study could provide references for further systematic study on the occurrence regularity of black soil erosion and soil loss control.