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Assessing Wind Erosion: A Review of Recent Measurement Techniques
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作者 Hetti Hewage Suranjith Ariyasena Xuerui Gao +2 位作者 Sohail Ahmad Jiaqiong Zhang Xining Zhao 《Open Journal of Soil Science》 2024年第9期499-529,共31页
Wind erosion represents a formidable environmental challenge and has serious negative impacts on soil health and agricultural productivity, particularly in arid and semi-arid areas. The complex dynamics of wind erosio... Wind erosion represents a formidable environmental challenge and has serious negative impacts on soil health and agricultural productivity, particularly in arid and semi-arid areas. The complex dynamics of wind erosion make its large-scale monitoring and quantification a daunting task. To facilitate the monitoring and quantification of wind erosion, various scientific approaches and methods have been employed. These include sophisticated wind erosion equations and models, wind tunnel experiments, and the application of radionuclides. Additionally, researchers have assessed soil physicochemical properties, used anemometers for wind speed measurement, and deployed dust collectors for particle capture. Remote sensing technologies, wind erosion monitoring stations, and evaluations of wind barriers have also been utilized. Recently, the adoption of machine learning methods has gained popularity. Despite their value, each of these techniques has limitations in capturing the full spectrum of the wind erosion process. This paper examines these limitations and assesses the effectiveness of each method in the context of wind erosion studies. It also outlines directions for future research and suggests pathways that could enhance the understanding and management of wind erosion. 展开更多
关键词 Wind erosion Wind erosion Models Remote Sensing Machine Learning
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Assessing the USLE Crop and Management Factor C for Soil Erosion Modeling in a Large Mountainous Watershed in Central China 被引量:12
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作者 Sarah Schnbrodt Patrick Saumer +2 位作者 Thorsten Behrens Christoph Seeber Thomas Scholten 《Journal of Earth Science》 SCIE CAS CSCD 2010年第6期835-845,共11页
Due to the impoundment of the Yangtze River, the Three Gorges Dam in China fosters high land-use dynamics. Soil erosion is expected to increase dramatically. One of the key factors in soil erosion control is the veget... Due to the impoundment of the Yangtze River, the Three Gorges Dam in China fosters high land-use dynamics. Soil erosion is expected to increase dramatically. One of the key factors in soil erosion control is the vegetation cover and crop type. However, determining these factors adequately for the use in soil erosion modeling is very time-consuming especially for large mountainous areas, such as the Xiangxi (香溪) catchment in the Three Gorges area. In our study, the crop and management factor C was calculated using the fractional vegetation cover (CFvc) based on Landsat-TM images from 2005, 2006, and 2007 and on literature studies (CLIT). In 2007, the values of CFvc range between 0.001 and 0.98 in the Xiangxi catchment. The mean CFVC value is 0.05. CLIT values are distinctly higher, ranging from 0.08 to 0.46 with a mean value of 0.32 in the Xiangxi catchment. The mean potential soil loss amounts to 120.62 t/ha/a in the Xiangxi catchment when using CLIT for modeling. Based on CFVC, the predicted mean soil loss in the Xiangxi catchment is 11.50 t/ha/a. Therefore, CLIT appears to bemore reliable than the C factor based on the fractional vegetation cover. 展开更多
关键词 C factor soil erosion modeling Universal Soil Loss Equation fractional vegetation cover Three Gorges Dam Yangtze River.
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Numerical study on erosion behavior of sliding sleeve ball seat for hydraulic fracturing based on experimental data
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作者 Xuan-Li Zhou Yan-Bao Guo +2 位作者 Qiu-Ju Xie De-Guo Wang Hyun C.Yoon 《Petroleum Science》 SCIE EI CAS CSCD 2023年第1期515-525,共11页
The sleeve sealing ball seat is one of the important components in the multistage fracturing process of horizontal wells.The erosion and wear of the surface will decrease the sealing performance of the fracturing ball... The sleeve sealing ball seat is one of the important components in the multistage fracturing process of horizontal wells.The erosion and wear of the surface will decrease the sealing performance of the fracturing ball and the ball seat.This leads to pressure leakage during the fracturing process and fracturing failure.In this paper,combined with the actual ball seat materials and working conditions during the fracturing process,the erosion tests of ductile iron and tungsten carbide materials under different erosion speeds,angles,and mortar concentrations are carried out.Then the erosion test results were analyzed by mathematical fitting,and a set of erosion models suitable for sliding sleeve setting ball seat materials were innovatively established.For the first time,this paper combines the erosion model obtained from the experiment and the computational fluid dynamics(CFD)with Fluent software to simulate the erosion of the ball seat.Based on the simulation results,the morphology of the sliding sleeve seat ball after erosion is predicted.Through analysis of the test and simulation results,it is showed that the erosion rate of tungsten carbide material is lower and the wear resistance is better under the condition of small angle erosion.This research can offer a strong basis for fracturing site selection,surface treatment methods,and prediction of failure time of ball seats. 展开更多
关键词 Multistage fracturing Sliding sleeve ball seat erosion wear erosion model Fluent simulation
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Study on Soil Erosion Model Under Different Slopes in Southwest Karst Mountain Area
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作者 高翔 王济 +1 位作者 蔡雄飞 胡丰青 《Agricultural Science & Technology》 CAS 2013年第12期1847-1851,共5页
The aim was to further research soil erosion characteristics and accurately predict soil erosion amount in karst areas. Based on field surveys and research achievements available, yellow soils, which are widely distri... The aim was to further research soil erosion characteristics and accurately predict soil erosion amount in karst areas. Based on field surveys and research achievements available, yellow soils, which are widely distributed, were chosen as test soil samples and slope, rain intensity, vegetation coverage and bare-rock ratio were taken as soil erosion factors. Artificial rain simulation instruments (needle-type) were made use of to simulate correlation of rain intensity, vegetation coverage, and bare-rock ratio with soil erosion quantity. Furthermore, multiple-factor linear regression analysis, stepwise regression analysis and multiple-factor non-linear regression analy- sis were made to establish a multiple-factor formula of soil erosion modulus with dif- ferent slopes and select regression models with high correlation coefficients. The re- sults show that a non-linear regression model reached extremely significant level or significant level (0.692〈FF〈0.988) and linear regression model achieved significant lev- el (0.523〈FF〈0.634). The effects of erosion modulus changed from decreasing to in- creasing and the erosion factors from high to low were rain intensity, vegetation cov- erage and bare-rock ratio when slope gradient was at 6~, 16~, 26~ and 36~. The mod- el is of high accuracy for predicting gentle slope and abtupt slope, which reveals correlation of erosion modulus with erosion factors in karst areas. 展开更多
关键词 Southwest karst mountain area SLOPE Soil erosion model
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Uncertainty Assessment of Soil Erosion Model Using Particle Filtering
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作者 Yeonsu KIM Giha LEE +1 位作者 Hyunuk AN Jae E YANG 《Journal of Mountain Science》 SCIE CSCD 2015年第4期828-840,共13页
Recent advances in computer with geographic information system(GIS) technologies have allowed modelers to develop physics-based models for modeling soil erosion processes in time and space.However, it has been widely ... Recent advances in computer with geographic information system(GIS) technologies have allowed modelers to develop physics-based models for modeling soil erosion processes in time and space.However, it has been widely recognized that the effect of uncertainties on model predictions may be more significant when modelers apply such models for their own modeling purposes.Sources of uncertainty involved in modeling include data, model structural, and parameter uncertainty.To deal with the uncertain parameters of a catchment-scale soil erosion model(CSEM) and assess simulation uncertainties in soil erosion, particle filtering modeling(PF) is introduced in the CSEM.The proposed method, CSEM-PF, estimates parameters of non-linear and non-Gaussian systems, such as a physics-based soil erosion model by assimilating observation data such as discharge and sediment discharge sequences at outlets.PF provides timevarying feasible parameter sets as well as uncertainty bounds of outputs while traditional automatic calibration techniques result in a time-invariant global optimal parameter set.CSEM-PF was applied to a small mountainous catchment of the Yongdamdam in Korea for soil erosion modeling and uncertainty assessment for three historical typhoon events.Finally, the most optimal parameter sets and uncertainty bounds of simulation of both discharge and sediment discharge at each time step of the study events are provided. 展开更多
关键词 Data assimilation Particle filter Soil erosion modeling Parameter estimation Time variant parameter Mountainous catchment
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Experimental investigation of erosion rate for gas-solid two-phase flow in 304 stainless/L245 carbon steel 被引量:3
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作者 Bingyuan Hong Yanbo Li +6 位作者 Xiaoping Li Gen Li ong Huang Shuaipeng Ji Weidong Li Jing Gong Jian Guo 《Petroleum Science》 SCIE CAS CSCD 2022年第3期1347-1360,共14页
Erosion is one of the most concerning issues in pipeline flow assurance for the Oil&Gas pipeline industries,which can easily lead to wall thinning,perforation leakage,and other crucial safety risks to the steady o... Erosion is one of the most concerning issues in pipeline flow assurance for the Oil&Gas pipeline industries,which can easily lead to wall thinning,perforation leakage,and other crucial safety risks to the steady operation of pipelines.In this research,a novel experimental device is designed to investigate the erosion characteristics of 304 stainless and L245 carbon steel in the gas-solid two-phase flow.Regarding the impacts on erosion rate,the typical factors such as gas velocity,impact angle,erosion time,particle material and target material are individually observed and comprehensive analyzed with the assistance of apparent morphology characterized via Scanning Electron Microscope.Experimental results show that the severest erosion occurs when the angle reaches approximate 30°whether eroded by type I or type II particles,which is observed in both two types of steel.Concretely,304 stainless steel and L245 carbon steel appear to be cut at low angles,and impacted at high angles to form erosion pits.In the steady operational state,the erosion rate is insensitive to the short erosion time and free from the influences caused by the“erosion latent period”.Based on the comparison between experimental data and numerical results generated by existing erosion models,a modified model with low tolerance(<3%),high feasibility and strong consistency is proposed to make an accurate prediction of the erosion in terms of two types of steel under various industrial conditions. 展开更多
关键词 Gas-solid flow erosion 304 stainless L245 carbon steel erosion model
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SOIL EROSION AND ITS IMPACTS ON ENVIRONMENT IN YIXING TEA PLANTATION OF JIANGSU PROVINCE 被引量:2
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作者 ZHANGYah ZHANGHong +1 位作者 PENGBu-zhuo YANGHao 《Chinese Geographical Science》 SCIE CSCD 2003年第2期142-148,共7页
Soil erosion on sloping field has led to a lot of environmental prob lems. In order to reveal the seriousness of the damage of soil erosion on slopin g fields 137Cs tracer method was used to estimate soil erosion rate... Soil erosion on sloping field has led to a lot of environmental prob lems. In order to reveal the seriousness of the damage of soil erosion on slopin g fields 137Cs tracer method was used to estimate soil erosion rate. 137Cs refer ence inventory of 2200Bq/m2 in Yixing, southern Jiangsu Province, was estimated and a model for estimating erosion of cultivated soil was established in order t o avoid overestimating soil erosion rates. Then based on the soil erosion rates and measured soil physical and chemical properties, direct and indirect impacts of soil erosion on environment were further discussed. Direct impacts of erosion on environment included on-site and off-site impacts. The on-site impacts we re that soil layer became thin, soil structure was deteriorated and soil nutrien ts decreased. The off-site impacts were that water bodies were polluted. The in direct impacts of soil erosion on environment were the increase of fertilizer ap plication and energy consumption, and change of adaptability of land uses. Altho ugh erosion intensity was not serious in the study area, its environmental impac ts should not be ignored because of great soil nutrient loss and coarseness of s oil particles. 展开更多
关键词 Cs reference inventory erosion model soil erosion equivalent erosion module
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Assessment of Soil Erosion by Compensatory Hoeing Tillage in a Purple Soil 被引量:8
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作者 SU Zhengan ZHANG Jianhui +1 位作者 XIONG Donghong LIU Gangcai 《Journal of Mountain Science》 SCIE CSCD 2012年第1期59-66,共8页
This study explores the role of a traditional tillage method,i.e.,compensatory hoeing,for sustainable agro-ecosystem management in the hilly areas of the Chongqing municipality,south-western China.To validate the effe... This study explores the role of a traditional tillage method,i.e.,compensatory hoeing,for sustainable agro-ecosystem management in the hilly areas of the Chongqing municipality,south-western China.To validate the effects of compensatory tillage on the terraced slopes,the tillage method of noncompensatory hoeing was conducted on a linear slope.To acquire information about 137 Cs inventories and soil texture,soil samples were collected by a core sampler with a 6.8-cm diameter at 5.0-m intervals along the toposequence and the linear slope in the dry season(March) of 2007.Meanwhile,a tillage erosion model was used for evaluating the spatial pattern of tillage erosion.The 137 Cs data showed that on the terraced slope,soil was lost from the upper slope,and soil deposition occurred at the toe slope positions on each terrace.As a result,abrupt changes in the 137 Cs inventories of soil were found over short distances between two sides of terrace boundaries.Results obtained from the tillage erosion model and the 137 Cs data indicate that soil redistribution mainly results from tillage erosion in the terraced landscape.Consecutive non-compensatory tillage caused soil redistribution on the linear slope,resulting in thin soil profile disappearing at the top and soil accumulating at the bottom positions of the linear slope.This result further validates that compensatory tillage could avoid the complete erosion of the thin soil layer at the summit position.Therefore,this traditional tillage.method,i.e.,compensatory tillage,has maintained the soil quality at the summit of the slope in the past decades. 展开更多
关键词 Compensatory tillage Tillage erosion model 137 Cs Three Gorges Reservoir region China
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An estimation method of soil wind erosion in Inner Mongolia of China based on geographic information system and remote sensing 被引量:6
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作者 Yi ZHOU Bing GUO +1 位作者 ShiXin WANG HePing TAO 《Journal of Arid Land》 SCIE CSCD 2015年第3期304-317,共14页
Studies of wind erosion based on Geographic Information System(GIS) and Remote Sensing(RS) have not attracted sufficient attention because they are limited by natural and scientific factors.Few studies have been c... Studies of wind erosion based on Geographic Information System(GIS) and Remote Sensing(RS) have not attracted sufficient attention because they are limited by natural and scientific factors.Few studies have been conducted to estimate the intensity of large-scale wind erosion in Inner Mongolia,China.In the present study,a new model based on five factors including the number of snow cover days,soil erodibility,aridity,vegetation index and wind field intensity was developed to quantitatively estimate the amount of wind erosion.The results showed that wind erosion widely existed in Inner Mongolia.It covers an area of approximately 90×104 km2,accounting for 80% of the study region.During 1985–2011,wind erosion has aggravated over the entire region of Inner Mongolia,which was indicated by enlarged zones of erosion at severe,intensive and mild levels.In Inner Mongolia,a distinct spatial differentiation of wind erosion intensity was noted.The distribution of change intensity exhibited a downward trend that decreased from severe increase in the southwest to mild decrease in the northeast of the region.Zones occupied by barren land or sparse vegetation showed the most severe erosion,followed by land occupied by open shrubbery.Grasslands would have the most dramatic potential for changes in the future because these areas showed the largest fluctuation range of change intensity.In addition,a significantly negative relation was noted between change intensity and land slope.The relation between soil type and change intensity differed with the content of Ca CO3 and the surface composition of sandy,loamy and clayey soils with particle sizes of 0–1 cm.The results have certain significance for understanding the mechanism and change process of wind erosion that has occurred during the study period.Therefore,the present study can provide a scientific basis for the prevention and treatment of wind erosion in Inner Mongolia. 展开更多
关键词 wind erosion estimation model soil erodibility snow cover days aridity Inner Mongolia
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Soil Erosion Modelling for Sustainable Environmental Management in Sebeya Catchment, Rwanda 被引量:1
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作者 Félicien Majoro Umaru Garba Wali +3 位作者 Omar Munyaneza François-Xavier Naramabuye Philibert Nsengiyumva Concilie Mukamwambali 《Journal of Water Resource and Protection》 2020年第12期1034-1052,共19页
Soil erosion models can be understood as a virtual laboratory that brings together data, observations and knowledge from different fields for sustainable environmental management. The present study was carried out on ... Soil erosion models can be understood as a virtual laboratory that brings together data, observations and knowledge from different fields for sustainable environmental management. The present study was carried out on Sebeya catchment which is located in the Western Province of Rwanda. The main objective of this study was to develop a Universal Soil Loss Equation type of erosion model to be used in predicting soil loss and associated crop yields for sustainable agriculture management in Sebeya catchment at the level of parcels. USLE parameters were determined on each parcel in Sebeya catchment using map overlapping techniques as applied in Geographical Information System (GIS). Applying a combination of 0, 1, 2 and 3 soil erosion control measures on each of 259,673 parcels, the simulated annual soil loss for Sebeya catchment was 849.94;143.27;88.64 and 28.59 t/ha/yr respectively. Soil Loss and Crop Yield (SOLCY) model has been developed to predict soil loss and crop yields for each main cultivated crop in Sebeya catchment. A combination of 3 soil erosion control measures such as (bench terrace + mulching + drainage channels) has been found to be the most effective in reducing soil erosion on each parcel with slope range of (16 - 60)%. Farmers and agriculture technicians can use SOLCY model. Finally, researchers should develop similar models on other catchments based on SOLCY model design concept. 展开更多
关键词 Sebeya Catchment erosion Modelling Crop Yield
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Applying seepage modeling to improve sediment yield predictions in contour ridge systems
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作者 LIU Qianjin MA Liang ZHANG Hanyu 《Journal of Arid Land》 SCIE CSCD 2020年第4期676-689,共14页
Contour ridge systems may lead to seepage that could result in serious soil erosion. Modeling soil erosion under seepage conditions in a contour ridge system has been overlooked in most current soil erosion models. To... Contour ridge systems may lead to seepage that could result in serious soil erosion. Modeling soil erosion under seepage conditions in a contour ridge system has been overlooked in most current soil erosion models. To address the importance of seepage in soil erosion modeling, a total of 23 treatments with 3 factors, row grade, field slope and ridge height, in 5 gradients were arranged in an orthogonal rotatable central composite design. The second-order polynomial regression model for predicting the sediment yield was improved by using the measured or predicted seepage discharge as an input factor, which increased the coefficient of determination(R^2) from 0.743 to 0.915 or 0.893. The improved regression models combined with the measured seepage discharge had a lower P(0.007) compared to those combined with the predicted seepage discharge(P=0.016). With the measured seepage discharge incorporated, some significant(P<0.050) effects and interactions of influential factors on sediment yield were detected, including the row grade and its interactions with the field slope, ridge height and seepage discharge, the quadratic terms of the field slope and its interactions with the row grade and seepage discharge. In the regression model with the predicted seepage discharge as an influencing factor, only the interaction between row grade and seepage discharge significantly affected the sediment yield. The regression model incorporated with predicted seepage discharge may be expressed simply and can be used effectively when measured seepage discharge data are not available. 展开更多
关键词 soil erosion model contour ridge SEEPAGE geometry factors rainfall simulation
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A Simplified Model for the Prediction of the Erosion of a Metal Screen for Sand Control
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作者 Baocheng Shi Ruomeng Ying +4 位作者 Lijuan Wu Jianpeng Pan Xingkai Zhang Kai Liu Yindi Zhang 《Fluid Dynamics & Materials Processing》 EI 2021年第3期667-682,共16页
In oil drilling processes,sand production in the oil layer is a common issue,generally mitigated by means of sand control screens.To prevent or reduce the risk of damage of these screens and to improve the related ser... In oil drilling processes,sand production in the oil layer is a common issue,generally mitigated by means of sand control screens.To prevent or reduce the risk of damage of these screens and to improve the related service life,it is necessary to investigate the related erosion dynamics.In this study,a screen mesh model based on the flow field similarity theory is proposed to overcome the otherwise too complex geometric structure of this type of equipment.Such model is optimized using experimental data.The predicted results are in good agreement with the measured values,and the error is less than 15%.The results also show that the simplified geometric screen model and the optimized Zhang et al.erosion model have high reliability;therefore,they could effective be used to select underground screen meshes and improve the design of production process. 展开更多
关键词 Metal sand control screen erosion model life prediction numerical simulation
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Comparison of Slope Length Factor Extraction in Hillslope Soil Erosion Model with Different DEM Resolutions
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作者 Feng KONG 《Agricultural Biotechnology》 CAS 2020年第1期89-95,共7页
In this study, non-cumulative slope length(NCSL) calculation method and spatial analytical calculation(SAC) method were respectively applied to extract slope length and slope length factor from 10 sample areas, which ... In this study, non-cumulative slope length(NCSL) calculation method and spatial analytical calculation(SAC) method were respectively applied to extract slope length and slope length factor from 10 sample areas, which are located in Ansai County, north Shaanxi Province. The comparison of computation precision between variable DEM resolutions showed that NCSL was superior to SAC entirely. And the results were best when the DEM resolutions were 5 and 10 m. Besides, the results of slope length factor were nearly the same under the two conditions. So DEM of 10 m resolution can be used to extract slope length. 展开更多
关键词 DEM RESOLUTION Slope length Precision differentiation Soil erosion model
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GIS Based Soil Erosion Estimation Using EPM Method, Garmiyan Area, Kurdistan Region, Iraq
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作者 Salahalddin S. Ali Foad A. Al-Umary +2 位作者 Sarkawt G. Salar Nadhir Al-Ansari Sven Knutsson 《Journal of Civil Engineering and Architecture》 2016年第3期291-308,共18页
Using empirical model is one of the approaches of evaluating sediment yield. This research is aimed at predicting erosion and sedimentation in Garmiyan area at Kurdistan Region, Iraq used EPM (erosion potential model... Using empirical model is one of the approaches of evaluating sediment yield. This research is aimed at predicting erosion and sedimentation in Garmiyan area at Kurdistan Region, Iraq used EPM (erosion potential model) incorporating into GIS (geographic information system) software. This basin area is about 1,620 km2. It has a range of vegetation, slope, geological, soil texture and land use types. The spatial distribution of gully erosion shows three main zones in the studied area (slight to moderate gully, high gully and sever fluvial erosion). They form about 10%, 89% and 1% of gully erosion in the studied area respectively. The results of the EPM model show that the values of the coefficient of erosion Z are classified as moderate to high erosion intensity. They increase northward due to increasing of slope, elevation and rate of precipitation that generate Hortonian overland flow, which is due to high discharge and huge fluvial erosion power that cause ground surface erosion to produce large quantity of sediment. The results of GSP (spatial sediment rate) are increasing northward similar to Z due the same reasons, while the value of total sediment rate, shows different values for each watershed because they are mainly affected by the total watershed area. 展开更多
关键词 Garmiyan erosion potential model geomorphology method erosion sediment yield Iraq Kurdistan Region
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Comprehensive Euler/Lagrange modelling including particle erosion for confined gas-solid flows 被引量:1
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作者 Guiherme A.Novelletto Ricardo Martin Sommerfeld 《Particuology》 SCIE EI CAS CSCD 2024年第1期209-235,共27页
The present research aims to assess the capability of a comprehensive Euler/Lagrange approach for predicting gas-solid flows and the associated solid particle erosion.The open-source code OpenFOAM®4.1 was used to... The present research aims to assess the capability of a comprehensive Euler/Lagrange approach for predicting gas-solid flows and the associated solid particle erosion.The open-source code OpenFOAM®4.1 was used to carry out the numerical simulations,where the standard Lagrangian libraries were substantially extended to account for all necessary models.Particles are tracked considering both translational and rotational motion as well as all relevant forces,such as gravity/buoyancy,drag and transverse lift due to shear and particle rotation.The tracking time step was dynamically adapted ac-cording to the locally relevant time scales,which drastically reduces computational times.Stochastic approaches are adopted to model particle turbulent dispersion,particle collisions with rough walls and particle-particle interactions.Five solid particle erosion models,available in the literature,were considered to estimate pipe bend erosion.Three study cases are provided to validate the adopted nu-merical approach and erosion models extensively.The first case intends to evaluate the ability of the extended CFD code to predict the behaviour of gas-solid flows in pneumatic conveying systems.This goal is achieved by comparing the numerical results with the experimental data obtained by Huber(1997)and Huber and Sommerfeld(1994,1998)in a pneumatic conveying system.Here,the importance of considering inter-particle collisions and surface roughness for predicting particle velocity,mass flux and mean diameter distributions in gas-solid flows is highlighted.The second and third case intend to evaluate the ability of the erosion models in estimating bend erosion in diluted gas-solid flows.The erosion data obtained experimentally by Mazumder et al.(2008)and Solnordal et al.(2015)in very dilut pneumatic conveying systems is used for validating the numerical results,neglecting now inter-particle collisions and two-way coupling.Besides a comprehensive analysis of the different influential properties on erosion,the innovation of the present study is as follows.For the first time also a temporal modifi-cation of the surface roughness due to the erosion was considered in the simulations obtained from previous measurements(Novelletto Ricardo&Sommerfeld,2020).As the surface roughness is increased due to erosion,eventually erosion rate becomes lower.This is the result of diminishing wall collision frequency.Simulations for several degrees of surface roughness showed that larger roughness is coupled with a drastic reduction of erosion.Hence,numerical simulations neglecting wall surface roughness are not realistic.The consideration of a particle size distribution instead of mono-sized computations showed a possible reduction of erosion rate.The detailed analysis of the different single-particle erosion models revealed that the model proposed by Oka et al.(2005)and Oka and Yoshida(2005)yields the best agreement with the measurements,however particle and wall properties are needed. 展开更多
关键词 Pneumatic conveying Pipe bend Numerical calculation(CFD) Euler/Lagrange approach erosion models Wall roughness
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Assessment of SoilGrids data for soil erosion estimation at watershed scale: A case study in northern Thailand
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作者 Chike Onyeka MADUEKE Dhruba Pikha SHRESTHA Panagiotis NYKTAS 《Pedosphere》 SCIE CAS CSCD 2024年第4期797-813,共17页
Soil erosion has been identified as one of the most destructive forms of land degradation,posing a threat to the sustainability of global economic,social and environmental systems.This underscores the need for sustain... Soil erosion has been identified as one of the most destructive forms of land degradation,posing a threat to the sustainability of global economic,social and environmental systems.This underscores the need for sustainable land management that takes erosion control and prevention into consideration.This requires the use of state-of-the-art erosion prediction models.The models often require extensive input of detailed spatial and temporal data,some of which are not readily available in many developing countries,particularly detailed soil data.The soil dataset Global Gridded Soil Information(SoilGrids)could potentially fill the data gap.Nevertheless,its value and accuracy for soil erosion modelling in the humid tropics is still unknown,necessitating the need to assess its value vis-à-vis field-based data.The major objective of this study was to conduct a comparative assessment of the value of SoilGrids and field-based soil data for estimating soil loss.Soil samples were collected from five physiographic positions(summit,shoulder,back slope,foot slope,and toe slope)using the soil catena approach.Samples were collected using a 5-cm steel sample ring(undisturbed)and a spade(disturbed).Data of the landform,predominant vegetation types,canopy cover,average plant height,land use,soil depth,shear strength,and soil color were recorded for each site.The soil samples were subjected to laboratory analysis for saturated hydraulic conductivity,bulk density,particle size distribution,and organic matter content.Pedotransfer functions were applied on the SoilGrids and field-based data to generate soil hydrological properties.The resultant field-based data were compared with the SoilGrids data for corresponding points/areas to determine the potential similarities of the two datasets.Both datasets were then used as inputs for soil erosion assessment using the revised Morgan-Morgan-Finney model.The results from both datasets were again compared to determine the degree of similarity.The results showed that with respect to point-based comparison,both datasets were significantly different.At the hillslope delineation level,the field-based data still consistently had a greater degree of variability,but the hillslope averages were not significantly different for both datasets.Similar results were recorded with the soil loss parameters generated from both datasets;point-based comparison showed that both datasets were significantly different,whereas the reverse was true for parcel/area-based comparison.SoilGrids data are certainly useful,especially where soil data are lacking;the utility of this dataset is,however,dependent on the scale of operation or the extent of detail required.When detailed,site-specific data are required,SoilGrids may not be a good alternative to soil survey data in the humid tropics.On the other hand,if the average soil properties of a region,area,or land parcel are required for the implementation of a particular project,plan,or program,SoilGrids data can be a very valuable alternative to soil survey data. 展开更多
关键词 hillslope modelling pedotransfer function similarity assessment soil erosion modelling soil loss soil survey
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Salt Balance of Moderately Saline-Alkaline Rangeland Soil and Runoff Water Quality from Rainfall Simulation Studies near Moab,Utah U.S.A.
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作者 Awadis Arslan Kossi Nouwakpo Mark Weltz 《Journal of Geological Resource and Engineering》 2020年第1期1-19,共19页
A Walnut Gulch rainfall simulator was used to determine runoff water quality and salt balance of a Sandy Loam moderately saline-alkaline site containing 0.27%of gypsum near Moab,Utah.Four rainfall intensities correspo... A Walnut Gulch rainfall simulator was used to determine runoff water quality and salt balance of a Sandy Loam moderately saline-alkaline site containing 0.27%of gypsum near Moab,Utah.Four rainfall intensities corresponding to 2,10,25 and 50-year storm return intervals were applied to dry soil.During each rainfall simulation,time-stamped runoff samples were also collected for the determination of ions concentration.Soil water and solute content by depth increments were determined before and after simulations.All correlation coefficients between the applied simulation water and the amounts of Cl-,SO42-,NO3-and sum of anions in runoff water were positive and ranged between 0.922 and 0.999.The correlation coefficients for Ca2+,Mg2+,Na+,K+and sum of cations ranged between 0.783 and 0.983.We concluded from the data analysis that:(1)The amounts of ions in simulation water and in runoff water represent less than 1%of sum of the soil soluble content before rainfall simulation.(2)The CEC contained about 250%the sum of cation in saturated extract.(3)The very small amount of gypsum in the soil contained 50%the sum of saturated extract ions.This means that special attention should be paid to CEC and gypsum content in the management of such soils.Moreover,when modeling runoff and water quality from soils with these properties the modelers must include suitable subroutines considering gypsum and CEC of the soil for accurate prediction of runoff water quality. 展开更多
关键词 erosion modeling rainfall simulation RANGELAND water quality SALINITY
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An Object-based Approach for Two-level Gully Feature Mapping Using High-resolution DEM and Imagery: A Case Study on Hilly Loess Plateau Region, China 被引量:12
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作者 LIU Kai DING Hu +4 位作者 TANG Guoan ZHU A-Xing YANG Xin JIANG Sheng CAO Jianjun 《Chinese Geographical Science》 SCIE CSCD 2017年第3期415-430,共16页
Gully feature mapping is an indispensable prerequisite for the motioning and control of gully erosion which is a widespread natural hazard. The increasing availability of high-resolution Digital Elevation Model(DEM) a... Gully feature mapping is an indispensable prerequisite for the motioning and control of gully erosion which is a widespread natural hazard. The increasing availability of high-resolution Digital Elevation Model(DEM) and remote sensing imagery, combined with developed object-based methods enables automatic gully feature mapping. But still few studies have specifically focused on gully feature mapping on different scales. In this study, an object-based approach to two-level gully feature mapping, including gully-affected areas and bank gullies, was developed and tested on 1-m DEM and Worldview-3 imagery of a catchment in the Chinese Loess Plateau. The methodology includes a sequence of data preparation, image segmentation, metric calculation, and random forest based classification. The results of the two-level mapping were based on a random forest model after investigating the effects of feature selection and class-imbalance problem. Results show that the segmentation strategy adopted in this paper which considers the topographic information and optimal parameter combination can improve the segmentation results. The distribution of the gully-affected area is closely related to topographic information, however, the spectral features are more dominant for bank gully mapping. The highest overall accuracy of the gully-affected area mapping was 93.06% with four topographic features. The highest overall accuracy of bank gully mapping is 78.5% when all features are adopted. The proposed approach is a creditable option for hierarchical mapping of gully feature information, which is suitable for the application in hily Loess Plateau region. 展开更多
关键词 object-based image analysis gully feature hierarchical mapping gully erosion Digital Elevation Model(DEM)
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Numerical analysis of submarine landslides using a smoothed particle hydrodynamics depth integral model 被引量:2
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作者 WANG Zhongtao LI Xinzhong +1 位作者 LIU Peng TAO Yanqi 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2016年第5期134-140,共7页
Submarine landslides can cause severe damage to marine engineering structures. Their sliding velocity and runout distance are two major parameters for quantifying and analyzing the risk of submarine landslides.Current... Submarine landslides can cause severe damage to marine engineering structures. Their sliding velocity and runout distance are two major parameters for quantifying and analyzing the risk of submarine landslides.Currently, commercial calculation programs such as BING have limitations in simulating underwater soil movements. All of these processes can be consistently simulated through a smoothed particle hydrodynamics(SPH) depth integrated model. The basis of the model is a control equation that was developed to take into account the effects of soil consolidation and erosion. In this work, the frictional rheological mode has been used to perform a simulation study of submarine landslides. Time-history curves of the sliding body's velocity, height,and length under various conditions of water depth, slope gradient, contact friction coefficient, and erosion rate are compared; the maximum sliding distance and velocity are calculated; and patterns of variation are discussed.The findings of this study can provide a reference for disaster warnings and pipeline route selection. 展开更多
关键词 sliding velocity runout distance smoothed particle hydrodynamics depth integral method frictional rheological model erosion effect
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Soil loss and sedimentation rates in a subcatchment of the Yellow river Basin in China
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作者 Simon Scheper Chunyue Liu +2 位作者 Zhongbao Xin Lishan Ran Christine Alewell 《International Soil and Water Conservation Research》 SCIE CSCD 2024年第3期534-547,共14页
Soil loss by water erosion is one of the main threats to soil health and food production in intensively used agricultural areas.To assess its significance to overall sediment production,we applied the Water and Tillag... Soil loss by water erosion is one of the main threats to soil health and food production in intensively used agricultural areas.To assess its significance to overall sediment production,we applied the Water and Tillage Erosion Model/Sediment Delivery model(WaTEM/SEDEM)to the Luoyugou catchment,a sub-catchment of the Yellow River Basin within the Chinese Loess Plateau.WaTEM/SEDEM considers rill and interrill erosion and deposition rates to calculate the sediment yield rates leaving the catchment.Ter-races were established in the 1990s to reduce soil loss in this area,but no soil erosion modeling has been published regarding the effect of this mitigation measure.Therefore,we applied 1000 Monte Carlo simulations of the WaTEM/SEDEM,and the modeled average soil loss by rill and interrill erosion for 2020 was 12.2±0.5 t ha^(-1)yr^(-1),with a sediment yield at the outlet of 53,207.8±11,244.1 t yr^(-1).The results indicated that the terracing reduced gross soil loss rates(from 51.8t ha^(-1)yr^(-1)in 1986 to 12.2±0.5 t ha^(-1)yr^(-1)in 2020),while land cover changes,mainly the conversion of forests and grassland,partly coun-teracted the mitigation(combined effect:76%reduction).Modeled sediment loads by rill and interrill erosion accounted for 22.8%of the total long-term sediment production recorded by flow discharge measurements.Other processes not considered by the model,such as landslides,gully erosion,riverbank erosion,and sediment production by construction,seem to predominantly influence the overall sedi-ment yield.Considering years with baseline sediment production only,the measured and modeled sediment yields compared favorably,indicating that the latter processes primarily contribute during extreme events. 展开更多
关键词 WaTEM/SEDEM erosion modeling Soil erosion rates Sediment load Risk assessment TERRACES
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