The characteristics of rill development and their effects on runoff and sediment yield under different slope gradients

摘要: Rill formation is the predominant erosion process in slope land Loess Plateau, China. This study was conducted to investigate rill characteristics and their effects on runoff sediment yielding processes under different gradients at a rate of 10°, 15°, 20° 25° with rainfall intensity 1.5 mm min−1 laboratory setting. Results revealed that mean depth density has positive interrelation gradient. To contrary, width-depth ratio distance longest top negatively related All these suggested increasing steepness could enhance headward erosion, vertical fragmentation surface. Furthermore, total tended approach stable maximum value slope, which implied there probably threshold gradient where soil begins weaken. At same time, correlation analysis showed close connection between various indices erosion: coefficients maximal depth, number rills from were 0.98, 0.97 −0.98, respectively, indicating major factor affecting development rills. not sensitive this study. Sediment concentration, however, positively formation, concentrations increased rapidly after initiation, especially. These results may be essential for loss prediction.