期刊文献+
共找到3篇文章
< 1 >
每页显示 20 50 100
The characteristics of rill development and their effects on runoff and sediment yield under different slope gradients 被引量:11
1
作者 HE Ji-jun SUN Li-ying +2 位作者 GONG Hui-li CAI Qiang-guo JIA Li-juan 《Journal of Mountain Science》 SCIE CSCD 2016年第3期397-404,共8页
Rill formation is the predominant erosion process in slope land in the Loess Plateau, China. This study was conducted to investigate rill erosion characteristics and their effects on runoff and sediment yielding proce... Rill formation is the predominant erosion process in slope land in the Loess Plateau, China. This study was conducted to investigate rill erosion characteristics and their effects on runoff and sediment yielding processes under different slope gradients at a rate of 10°, 15°, 20° and 25° with rainfall intensity of 1.5 mm min-1 in a laboratory setting. Results revealed that mean rill depth and rill density has a positive interrelation to the slope gradient. To the contrary, width-depth ratio and distance of the longest rill to the top of the slope negatively related to slope gradient. All these suggested that increasing slope steepness could enhance rill headward erosion, vertical erosion and the fragmentation of the slope surface. Furthermore,total erosion tended to approach a stable maximum value with increasing slope, which implied that there is probably a threshold slope gradient where soil erosion begins to weaken. At the same time, the correlation analysis showed that there was a close connection between slope gradient and the variousindices of soil erosion: the correlation coefficients of slope gradient with maximal rill depth, number of rills and the distance of the longest rill from the top of the slope were 0.98, 0.97 and-0.98, respectively,indicating that slope gradient is the major factor of affecting the development of rills. Furthermore,runoff was not sensitive to slope gradient and rill formation in this study. Sediment concentration,however, is positively related to slope gradient and rill formation, the sediment concentrations increased rapidly after rill initiation, especially. These results may be essential for soil loss prediction. 展开更多
关键词 Rill erosion Erosion processes Simulated rainfall runoff slope gradient
下载PDF
Effects of Shrub on Runoff and Soil Loss at Loess Slopes Under Simulated Rainfall 被引量:6
2
作者 XIAO Peiqing YAO Wenyi +3 位作者 SHEN Zhenzhou YANG Chunxia LYU Xizhi JIAO Peng 《Chinese Geographical Science》 SCIE CSCD 2017年第4期589-599,共11页
Improved understanding of the effect of shrub cover on soil erosion process will provide valuable information for soil and water conservation programs.Laboratory rainfall simulations were conducted to determine the ef... Improved understanding of the effect of shrub cover on soil erosion process will provide valuable information for soil and water conservation programs.Laboratory rainfall simulations were conducted to determine the effects of shrubs on runoff and soil erosion and to ascertain the relationship between the rate of soil loss and the runoff hydrodynamic characteristics.In these simulations a 20° slope was subjected to rainfall intensities of 45,87,and 127 mm/h.The average runoff rates ranged from 0.51 to 1.26 mm/min for bare soil plots and 0.15 to 0.96 mm/min for shrub plots.Average soil loss rates varied from 44.19 to 114.61 g/(min·m^2) for bare soil plots and from 5.61 to 84.58 g/(min·m^2) for shrub plots.There was a positive correlation between runoff and soil loss for the bare soil plots,and soil loss increased with increased runoff for shrub plots only when rainfall intensity is 127 mm/h.Runoff and soil erosion processes were strongly influenced by soil surface conditions because of the formation of erosion pits and rills.The unit stream power was the optimal hydrodynamic parameter to characterize the soil erosion mechanisms.The soil loss rate increased linearly with the unit stream power on both shrub and bare soil plots.Critical unit stream power values were 0.004 m/s for bare soil plots and 0.017 m/s for shrub plots. 展开更多
关键词 runoff soil loss shrub bare soil rainfall intensity loess slope
下载PDF
NUMERICAL SIMULATION OF ATOMIZATION RAINFALL AND THE GENERATED FLOW ON A SLOPE 被引量:2
3
作者 LIU Shi-he TAI Wei +1 位作者 FAN Min LUO Qiu-shi 《Journal of Hydrodynamics》 SCIE EI CSCD 2012年第2期273-279,共7页
This article studies the atomization rainfall and the generated flow on a slope by numerical simulations.The atomization rainfall is simulated by a unified model for splash droplets and a suspended mist,and the distri... This article studies the atomization rainfall and the generated flow on a slope by numerical simulations.The atomization rainfall is simulated by a unified model for splash droplets and a suspended mist,and the distribution of the diameter of splash rain drops is analyzed.The slope runoff generated by the atomization rainfall is simulated by a depth-averaged 2-D model,and the localization of the rainfall intensity in space is specially considered.The simulation results show that:(1) the median rain size of the atomization rainfall increases in the longitudinal direction at first,then monotonously decreases,and the maximum value is taken at the longitudinal position not in consistent with the position where the maximum rain intensity is taken.In the lateral direction the median rain size monotonously decreases,(2) since the atomization rainfall is distributed in a strongly localized area,it takes a longer time for its runoff yield to reach a steady state than that in the natural rainfall,the variation ranges of the water depth and the velocity in the longitudinal and lateral directions are larger than those in the natural rainfall. 展开更多
关键词 atomized flow unified model slope runoff numerical simulation
原文传递
上一页 1 下一页 到第
使用帮助 返回顶部