Abstract: The development of the slope of micro-relief reflects the intensity and process of erosion. To quantitatively study the response between the characteristics of micro-relief variation and the amount of erosion,three consecutive rainfall tests with simulated precipitation of 1.5 mm·min^-1 were conducted,and the spatial variation characteristics of micro-relief and soil erosion were analyzed using 3-D laser scanner technology. The relationship between the amplitude of micro-relief and erosion was well fitted. The results showed that average sediment concentrations on the slope were reduced as the number of rainfall events increased. The lengths of the main sandpredicted area on the sand covered slope were about three times that of the loess slope,and peaks of the amount of erosion of the slope were mostly found at the position of 4-6 m on the slope,but the peaks of erosion on the loess slope were found in the position of 3-4 m. As the rainfall simulation progressed,the micro-relief factors of the loess slope increased significantly (P<0.05),and the micro-relief factors of the sand-covered slope increased,but not significantly (P>0.05). The study found that the micro-relief factors with the strongest erosion response to the loess slope and the sand-covered slope were surface incision and surface roughness,respectively. The response relationship between micro-relief variation and erosion of the loess slope was stronger than for the sand-covered slope,so the sand-covered slope should be examined for other sensitive indicators to optimize the equation. This study provides reference information for determining the erosion mechanism of wind water erosion across the region.

Key words: sand-covered slope, erosion, spatial distribution, microrelief, sand content, soil erosion