Effect of shrub-grass vegetation coverage and slope gradient on runoff and sediment yield under simulated rainfall

2021 ◽  
Vol 36 (1) ◽  
pp. 29-37
Author(s):  
Dandan Han ◽  
Jingcheng Deng ◽  
Chaojun Gu ◽  
Xingmin Mu ◽  
Peng Gao ◽  
...  
2011 ◽  
Vol 347-353 ◽  
pp. 2094-2097 ◽  
Author(s):  
Pei Qing Xiao ◽  
Wen Yi Yao ◽  
Chang Gao Wang

Runoff, sediment yield and infiltration process of shrub plots were studied under rainfall intensities of 45, 87 and 127 mm/h with 20° slope gradient using simulated rainfall experiment. The results showed that cumulative runoff and cumulative sediment yield of shrub plot had an obvious positive correlation with rainfall time. Under rainfall intensity of 45 mm/h, runoff and sediment yield of shrub plot kept a constant level. Under rainfall intensity of 87 mm/h, runoff kept a fluctuant increase, whereas sediment yield basically kept steady. Under rainfall intensity of 127 mm/h, runoff and sediment yield of shrub plot increased evidently due to the formation of erosion pits. Infiltration rate of shrub plot had a negative relation with runoff as well as sediment yield.


2012 ◽  
Vol 212-213 ◽  
pp. 141-144
Author(s):  
Pei Qing Xiao ◽  
Wen Yi Yao ◽  
Chang Gao Wang

Effect of shrub on runoff and sediment yield and its hydraulic mechanism of shrub were studied under rainfall intensities of 45, 87 and 127mm/h with 20°slope gradient using simulated rainfall experiment. the results showed that average runoff rates ranged from 39.7 to 126.0 L/min for bare plots and 0.77 to 4.83 L/min for shrub plots, and the runoff rates from shrub plots were much less than from bare plots. Average sediment yields varied from 3636.7 to 9436.3 g/min for bare plots and from 28.0 to 421.6 g/min for shrub plots. The critical flow shear stress of 1.65 N/m2 on shrub slope and 0.861 N/m2 on bare slope were got under experiment condition. The sediment yield increased with the increase of flow shear stress. The experiment results are meaningful for quantifying runoff and sediment reduction and deepening soil erosion mechanical process also.


2019 ◽  
Vol 11 (13) ◽  
pp. 3685 ◽  
Author(s):  
Yifan Zhang ◽  
Qinghe Zhao ◽  
Zihao Cao ◽  
Shengyan Ding

Riparian vegetation plays a vital role in soil and water conservation and river health maintenance. However, its inhibiting effects on water and soil loss are limited by different factors, such as slope gradient, vegetation coverage and their interaction. Therefore, this study quantified the inhibiting effect of riparian vegetation on the runoff, sediment and hydraulic characteristics of overland flow, and assessed its relative contribution to slope gradient. Specifically, we selected a riparian slope along the lower Yellow River as a case, and used a field-simulated rainfall experiment under specific rainfall intensity (90 mm/h), different vegetation coverage (0%, 15% and 30%) and slope gradients (5°, 10°, 15° and 20°). The results showed that the presence of vegetation can reduce the slope runoff rate and erosion rate. However, greater slope gradients can result in a lowering of the inhibiting effects of riparian vegetation on sediment yield. There was a critical value of vegetation coverage for inhibiting eroded sediments which was influenced by the degree of slope gradient. At 15% vegetation coverage, vegetation inhibited the slope sediment yield greatly at a slope gradient of less than 8°; while at 30% vegetation coverage, vegetation greatly inhibited the slope sediment yield at slope gradients <11°. Hydraulic characteristics were closely related to the slope gradient and vegetation coverage by the power function. Grey correlation analysis revealed that, with increasing of vegetation coverage, the effect of stream power on slope sediment yield decreased, while the effect of the friction coefficient on slope sediment yield increased. In summary, riparian vegetation can effectively inhibit slope runoff and sediment yield, but its inhibiting effect is notably affected by slope gradient.


Soil Research ◽  
2016 ◽  
Vol 54 (3) ◽  
pp. 291 ◽  
Author(s):  
Juan Wang ◽  
Jun Huang ◽  
Pute Wu ◽  
Xining Zhao

Soil erosion is a dynamic environmental process that influenced by multiple factors. However, most previous studies only examined the causative factors without ranking their relative importance or examining the individual factors. In this work, back-propagation (BP) neural network modelling and grey relational analysis were used to rank the effects of 7 factors—vegetation growth stage (VGS), vegetation type (VT), vegetation cover (VC), rainfall intensity (RI), rainfall duration (RD), antecedent soil moisture (ASM) and slope gradient (SG)—on total runoff (TR) and total sediment (TS) following simulated rainfall events at 5 intensities (30, 45, 60, 90, 120 mm h–1). The experimental plots including 4 treatments, bare soil (control), ryegrass (Lolium perenne L.), purple medic (Medicago sativa L.) and spring wheat (Triticum aestivum L.) under 4 different slopes (9%, 18%, 27.8%, 36.4%). BP models were constructed to predict TR and TS; their predictions tracked the experimental data very closely. A factor analysis based on the BP models ranked the influence of the 7 factors on TR and TS as RI > VC > ASM > RD > VGS > VT > SG and RI > VC > SG > ASM > RD > VGS > VT, respectively. Grey relational analysis provided similar results, ranking the effects of these factors on TR and TS in the order RI > VC > ASM > RD > SG > VGS > VT and RI > VC > SG > ASM > RD > VT > VGS, respectively. These results indicate that runoff and sediment yield depend most strongly on RI and VC, while the effects of the other factors are less pronounced.


2019 ◽  
Vol 26 (31) ◽  
pp. 32559-32573
Author(s):  
Longzhou Deng ◽  
Liping Zhang ◽  
Xiaojuan Fan ◽  
Tianyu Sun ◽  
Kai Fei ◽  
...  

2006 ◽  
Vol 20 (18) ◽  
pp. 3815-3824 ◽  
Author(s):  
Chengzhong Pan ◽  
Zhouping Shangguan ◽  
Tingwu Lei

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