CrossRef Google Scholar Govers, G.71 and 2. . Physical rill development includes three sub-processes: headcut 2022 · The measured rill flow velocities were 0. 107 [10] All the experimental runs were conducted in a 108 recirculating system, which had a rainfall module 1. The overall predominance of parallel - 21 shaped rills at all experiments suggested that the formation of rills was dominat ed by concentrated runoff. Raindrop impact and overland flow remove soil from the original cohesive soil. They used the correction factor α of 0. 2023 · Sediment transport capacity in rills is an important parameter for erosion modeling on hillslopes. Earth Surface Processes and Landforms, 17(5), 515–528.0 times higher when changing from 90 to 120 mm·h−1. A theoretical rill flow resistance equation, obtained by the integration of a power velocity distribution, was assessed using available measurements at plot scale with a biochar added soil.
25 times of Rill pattern 1 . This study used three experimental design methods, including the full ., 2002, Wu and Zhu, 1994). 2017 · A new theoretical flow resistance equation is proposed for step-pool rills. · The soil's resistance to concentrated flow erosion is an important factor for predicting rill and (ephemeral) gully erosion rates. The decrease in hydraulic roughness as a function of Nr is well documented [Chow, 1959, pp.
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In conclusion, there were important impacts of rainfall intensity and slope gradient on rill erosion processes and its hydrodynamic characteristics.0 rills/m was found . The bottom and inner walls of rills were mainly scoured, and the rills collapsed due to the hollowing of the walls by the rill flow, which caused rills to become less stable under gravity (Fig. The two parallel experiments under two snowmelt waterflow rates showed consistent results with respect to the process of runoff generation and sediment transport and in terms of the influence of thawed soil depth, thus demonstrating … 2018 · For a developing rill, the rill flow velocity is variable responding to the changing rill geometry; whereas the rill flow velocity shows limited variability with time for a … 2016 · After the flow discharge stabilised, flow depth measurements were taken using a level probe with an accuracy of 0. Gauze cloth approximately 0.4.
녹스 블루 스택 However, the rill development on the frozen slope was completely different from that of the unfrozen and shallow-thawed slopes. Since rill erosion is formed by concentrated flow, investigating the erosion condition necessitates analyzing hydraulic and hydrodynamic factors. · Overland flow caused by rainfall is one of the critical factors influencing soil erosion and loss of soil nutrients. A simulation experiment was performed to investigate the effects of polyacrylamide application rates … · Rill flow velocity was the optimal flow hydraulic parameter and stream power was the optimal hydrodynamic parameter to characterize the rill erosion mechanisms. Sediment load reached steady state conditions within the 8-m distance on the rill.Sediment transport through rills accounts for about 50–70% of total soil erosion (Morgan, 2005).
11 A-3, B-3, C-3)., 2002).50 m × 1. Surface runoff, or overland flow, is a fundamental process of interest in hydrology. 2020 · For rill flow, α increased linearly with increasing rill width, depth and cross-sectional area. For UDS with lower clay and higher sand content, the average sediment yield rate and . Modeling sediment concentration of rill flow - ScienceDirect Sep 1, 2022 · The sediment transport capacity by overland flow (T c) is a key parameter in process-based soil erosion models and T c variation is sensitive to changes in soil study was undertaken to investigate T c variations with respect to soil properties and establish a universal relationship to predict T test soils were … 2016 · The rill flow of UDQ had slower velocity and larger Dar-cy-Weisbach resistance coefficient than that of UDS. 2022 · Rill development is the process of soil detachment and sediment transport by concentrated surface flow (Kimaro et al. The effect of t on flow resistance has been little investigated for rills.34-mm raindrop impacts before rill development (Figures 10b and 10c).8m 2015 · A series of inflow experiments was conducted on loess slopes.2 m in length was placed at soil surface of the rill inlet to protect the rill surface from being directly scoured by the water flow.
Sep 1, 2022 · The sediment transport capacity by overland flow (T c) is a key parameter in process-based soil erosion models and T c variation is sensitive to changes in soil study was undertaken to investigate T c variations with respect to soil properties and establish a universal relationship to predict T test soils were … 2016 · The rill flow of UDQ had slower velocity and larger Dar-cy-Weisbach resistance coefficient than that of UDS. 2022 · Rill development is the process of soil detachment and sediment transport by concentrated surface flow (Kimaro et al. The effect of t on flow resistance has been little investigated for rills.34-mm raindrop impacts before rill development (Figures 10b and 10c).8m 2015 · A series of inflow experiments was conducted on loess slopes.2 m in length was placed at soil surface of the rill inlet to protect the rill surface from being directly scoured by the water flow.
Rill Erosion on Slope of Spoil tips: experimental study of
1 m rill hydraulic flume with a constant . There is an increasing trend for sediment load and sediment concentration with the rising slope gradient . Runoff and sediment yield samples were collected.In cultivated lands, rill erosion can lead to significant reduction of soil fertility and reduces … Sep 30, 2021 · Relationship between discharge, velocity and flow area for rills eroding loose, non-layered materials. The results of this study provide a reference for rill flow velocity measurement using the dye tracer method., 2009 .
This paper reports the results of a plot investigation aimed to establish the suitable accuracy of the rill thalweg measurement to determine the … 2016 · The rill flow of UDQ had slower velocity and larger Darcy–Weisbach resistance coefficient than that of UDS. 2016 · Dc by rill flow (expressed in kg m −2 s −1) was calculated as: (5) D c = W W - W d t × A where WW is the weight of the dry soil before testing (kg), Wd is the weight of the dry soil after testing (kg), t is the duration of the test (s), and A is the sample cross-section area (m 2 ). Dc was positively correlated with soil porosity and saturated hydraulic conductivity and negatively correlated with soil bulk density, water-stable aggregate content, organic . 2018 · creased in the rill as flow rate increased.0 cm and slopes ranged from 0. These parameters reflect soil resistance to runoff [59] and .수다 여자랑 후타나리만 존재하는 세계로 가고싶다
These measurements were replicated 2–3 times and then were averaged. This paper reports the results of a plot investigation aimed to establish the suitable accuracy of the rill thalweg measurement to determine the … 2021 · Purpose In this paper, a deduced flow resistance equation for open-channel flow was tested using measurements carried out in mobile bed rills with sediment-laden flows and fixed bed rills. The results were very good and demonstrated the simplicity and robustness of the method.. (1988). The value of α could be estimated with an equation of the rill depth and Reynolds number (R² = 0.
g. Sep 21, 2022 · Once rill forms on a slope, the slope flow will converge into concentrated rill flow by inter-rill flow, and the slope runoff velocity and flow depth will increase to varying degrees, leading to the intensification of slope soil erosion [4,5,6]. 2019 · Surface flow velocities (interrill and rill) demonstrate less significant differences along erosion stages., 2022) for steady state overland flow that rill processes are linked to the distribution of dissipation rates and therefore affect the energy balance. Stepwise regression results indicated a positive dependence of the flow … 2017 · 1. While it is often treated as a calibration parameter in process-based soil erosion models, global change studies require the estimation of erosion resistance from measurable soil properties.
79–6. Rill erosion contributes higher soil loss than sheet erosion (Zhu and Cai, 2004). For an open channel flow the local flow velocity profile v(y) along a given vertical is expressed by the following functional relationship (Barenblatt, 1987, Barenblatt, 1993, Ferro, 1997, Di Stefano et al.2 m above the lower end of the flume. The upper flume … · PDF | The model of soil erosion on a plane slope introduced by Hairsine and Rose (this issue) is further developed by considering rill flow. At each distance, depths were, respectively, measured at points 1. , 2007), so rill development is largely affected by flow erosivity and soil anti-erodibility. See more. The flow 2023 · 1. The first part of the paper is based on a theoretical equation to estimate the Darcy–Weisbach friction factor f, deduced from the power velocity distribution and rill measurements performed on a plot. For the Y-shaped rills in Plot 2, the excess rainfall and sediment generated from upstream interrill areas are delivered downslope into rills intercepting the interrill flow pathways and much more interrill flow and sediment can converge into the . Decreasing the SWFD from 15 to 5 cm increased … · The applicability of a theoretical rill flow resistance equation, based on the integration of a power velocity distribution, was tested using measurements carried out in mobile and fixed bed rills . 붉은 비키니 2022 · Actually, when the rill develops to a certain stage, sheet water flow carries soil particles into the rill, which provides water flow and part of the sediment source for rill erosion. Many mathematical models that simulate the details of runoff and erosion process in hillslopes, where the rill-interrill configuration significantly affects overland flow, employ Horton’s model for infiltration due … · The maximum rill flow depth and erosion intensity are about 2. 2021 · The rill sediment transport capacity value is widely used to clarify the soil erosion processes under overland flow conditions, which are sensitive to many hydraulic and sediment property parameters such as flow discharge rate, water depth, slope gradient, sediment particle sizes, and soil cohesion (Abrahams and Gao, 2006, Zhang et al. The hydraulic shear of flowing water and soil properties influence rill erosion.g. 2023 · The path tortuosity t is an indicator of rill morphology accounting for the deviation of the thalweg from a straight alignment. rill是什么意思_rill怎么读_rill翻译_用法_发音_词组_同反义词
2022 · Actually, when the rill develops to a certain stage, sheet water flow carries soil particles into the rill, which provides water flow and part of the sediment source for rill erosion. Many mathematical models that simulate the details of runoff and erosion process in hillslopes, where the rill-interrill configuration significantly affects overland flow, employ Horton’s model for infiltration due … · The maximum rill flow depth and erosion intensity are about 2. 2021 · The rill sediment transport capacity value is widely used to clarify the soil erosion processes under overland flow conditions, which are sensitive to many hydraulic and sediment property parameters such as flow discharge rate, water depth, slope gradient, sediment particle sizes, and soil cohesion (Abrahams and Gao, 2006, Zhang et al. The hydraulic shear of flowing water and soil properties influence rill erosion.g. 2023 · The path tortuosity t is an indicator of rill morphology accounting for the deviation of the thalweg from a straight alignment.
Db 실비 보험 g. Studies have shown that rill erosion can account for more than 90% of total slope erosion [7,8].2 m, 2. · Soil detachment by rill flow is a key sub-process of rill erosion on hillslope areas; however, many studies have focused on soil detachment by clear rather than by sediment-laden rill flow and most studies have used the time- and labor-consuming full-factorial design. Sep 17, 2021 · Since rill erosion depends on rill flow characteristics , a key to model rill erosion processes is to determine hydraulic variables as flow discharge Q, water depth … 2017 · Seven flow discharges were combined with six slopes. 2.
8, 0., 1984) and for this reason to study and model rill erosion processes, in addition to flow discharge, other hydraulic variables as surface width, water depth, mean flow velocity and roughness coefficient must be defined (Gilley et al. The sediment distribution function is the main issue in this context., 2000, Beuselinck et al. In measuring the STC and the sediment delivery process, four water samples at the outlet of the soil flume were consecutively collected using 300-mL steel cups for each experimental run after stabilizing the water flow. 2020 · After adjusting the flume to the designed slope gradient, water flow at the designed discharge was introduced into the rill at the top end.
This suggests that the physical roughness had a lesser influence on the hydraulic resistance as flow depth increased. The results show that the geometric and hydraulic properties of rill on the steep loess slopes, which are characterized by the mean width of cross sections, mean velocity and mean depth of flow, are related to discharge and slope gradient in power functions. From a practical standpoint, rill erosion forms small channels . The sediment concentration was determined with the traditional oven-dry method. Therefore, the study on the mechanism and controlling measures of soil nutrient transport proposed is considered important. The effect of t on flow resistance has been little investigated for rills. Flow resistance of overland flow on a smooth bed under
2020 · A set of conceptual equations using flow hydraulic and erosion properties are proposed to simulate evolving rill characteristics; A theoretical framework is presented to simulate coupled rill evolution and soil erosion processes; The coupled model is sensitive to the rill evolution parameters, rainfall intensity, and slope angle · apply to rill areas in which runo and sediment delivered from interrill areas are combined with erosion and transport processes by rill ows (Toy et al. Therefore, the applicability of . This solution considers the .610 m s−1 under the various . The first part of the paper is based on a theoretical equation to estimate the Darcy–Weisbach friction factor f, deduced from the power velocity distribution and rill measurements performed on … 1990 · Rill density and rill flow rates were determined during rainfall simulation tests conducted at 11 sites located throughout the eastern United States. Rills often occur between crop rows or along tillage marks.1004 주소 2023nbi
【IT运维管理软件产品】锐捷网络为您提供各种IT运维管理软件产品，包括RIIL-BMC 综合业务管理平台、RIIL-Emotion 自动化运维平台、RIIL-RMC 服务请求管理软件等IT运维管理 … 2022 · As a result, the pulse boundary model fit the electrolyte transport processes very well under the different SWFDs.80 for laminar flow, mixed flow (or transition flow), or turbulent flow, respectively. Rill Erosion. Limited information is currently available on how sediment transport affects rill flow resistance and the influence of hydraulic variables, as stream power, on sediment … 2000 · 1. Independent data sets from three sources representing both finely aggregated clay soils and coarse textured nonaggregated soils, sheet, rill, and composite sheet rill flow systems, and a range of slopes were used to test the utility of the method., 1990).
Statistically, power, exponential and logarithmic-linear equations can be used to describe the interrelations of . At 9 l min −1 discharge, 8 m length, and excess sediment added to the flow .202 to 0. After the water flow in the soil flume approached the steady state, sediment-laden water samples were collected at the outlets of the rills of various lengths (1 m, 2 m, 3 m, 4 m, 5 m, 6 m, 7 m and 8 m) before … 2018 · In this study, we investigated rill flow velocity regimes for both developing and stationary rills using 5 m-length plots in the laboratory.5, and 0. 2021 · The results showed that the correction factor increases with the roughness height for the sediment-free flow while for the sediment-laden flow an inverse relationship between α v and the sediment load can be established [10, 33].
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