Pages 781-909 (December 2023)
1. Local scour around submerged angled spur dikes under ice cover
Guowei LI · Jueyi SUI · Sanaz SEDIQI · Mauricio DZIEDZIC
Pages 781-793
2. A two-dimensional double layer-averaged model of hyperconcentrated turbidity currents with non-Newtonian rheology
Yining SUN · Ji LI · Zhixian CAO · Alistair George Liam BORTHWICK
3. Scour hole reduction at a diversion channel junction using different entrance edge shapes
Ahmed Yahya ABDULHAFEDH · Nashwan Kamalaldeen ALOMARI · Ahmed Mohammed Sami AL-JANABI
4. Experimental study on the effect of hydrodynamic conditions on flocculation and settling properties of fine-grain sediment
Bismark ODUM · Chunyang XU · Yongping CHEN · Yinpeng YAO · Yan ZHOU
5. Assessment of ecological risk for heavy metals in surface sediment of an urban river in a developing country
Md Saiful ISLAM · Md Humayun KABIR · Mir Mohammad ALI · Md Towhidul ISLAM · Asfi a NIGER · Md Humayun KABIR · Zulhilmi ISMAIL · Sujat AHMED · Khalid A. IBRAHIM · Abubakr M. IDRIS
6. Ensemble and optimized hybrid algorithms through Runge Kutta optimizer for sewer sediment transport modeling using a data pre-processing approach
Enes GUL · Mir Jafar Sadegh SAFARI · Omer Faruk DURSUN · Gokmen TAYFUR
7. Robust low-rank learning multi-output regression for incipient sediment motion in sewer pipes
Mir Jafar Sadegh SAFARI · Shervin RAHIMZADEH ARASHLOO
8. Characterization of the micro-interfacial interactions of heterogeneous particulate matter (fine-grained sediment and microplastics) with copper ions
Jing OU · Zhihe CHEN · Tung-Chiung CHANG
9. Experimental study on flocculation and sedimentation characteristics of cohesive fine sediment measured using ultrasound in the Pearl River Estuary
Qinqin LIU · Xiaojian LIU · Jian CHEN · Peng HOU · Yong HE · Qisong WANG · Xiaowei ZHU · Qiang WANG · Huan GAO
10. Index model equation analysis: A case study of the risk and source of inorganic contaminants in roadside uncontaminated soil of the Egi oil producing area, Niger Delta
Elechi OWHOEKE · Asmat ALI · Okorondu Justin NNAEMEKA · Kingsley John ORIE · Julius Nkeonyeasua EHIWARIO · Abdur RASHID
11. Establishment and development of the World Association for Sedimentation and Erosion Research
Cheng LIU · Zhaoyin WANG · Des E. WALLING
Pages 901-909
1. Local scour around submerged angled spur dikes under ice cover
Guowei LI · Jueyi SUI · Sanaz SEDIQI · Mauricio DZIEDZIC
Pages 781-793
https:/irtces/doi.org/10.1016/j.ijsrc.2023.08.003
Abstract: Local scour is a phenomenon leading to the localized lowering of the channel bed due to the imbalance of sediment transport. As spur dikes protrude into the natural channels, local scour could be triggered. Accurate estimation of local scour around spur dikes is crucial for the effectiveness of erosion control and prevention and habitat enhancement measures. In the current study, the correlations between the maximum scour depth and the overtopping ratio, spur dike dimensions, ice cover roughness, and grain size of the bed material are investigated. Under both open channel and ice-covered flow conditions, a variety of experiments were done in a large-scale outdoor flume with different experimental setups. The results revealed that the scour depths around submerged spur dikes increased with increases in the densimetric Froude number and the decreases in the overtopping ratio and alignment angle. The maximum scour depth around a submerged angled vertical wall spur dike is significantly affected by the presence of an ice cover on the water surface, namely, the rougher the cover, the deeper the scour hole. Based on data collected from the laboratory experiments, an existing maximum scour depth estimation equation has been modified to consider the influence of the cover condition and the submergence level. The calculated results showed high accuracy in estimation of the measured data.
2. A two-dimensional double layer-averaged model of hyperconcentrated turbidity currents with non-Newtonian rheology
Yining SUN · Ji LI · Zhixian CAO · Alistair George Liam BORTHWICK
Pages 794-810
https:/irtces/doi.org/10.1016/j.ijsrc.2023.08.002
Abstract: Hyperconcentrated turbidity currents typically display non-Newtonian characteristics that influence sediment transport and morphological evolution in alluvial rivers. However, hydro-sediment-morphological processes involving hyperconcentrated turbidity currents are poorly understood, with little known about the effect of the non-Newtonian rheology. The current paper extends a recent two-dimensional double layer-averaged model to incorporate non-Newtonian constitutive relations. The extended model is benchmarked against experimental and numerical data for cases including subaerial mud flow, subaqueous debris flow, and reservoir turbidity currents. The computational results agree well with observations for the subaerial mud flow and independent numerical simulations of subaqueous debris flow. Differences between the non-Newtonian and Newtonian model results become more pronounced in terms of propagation distance and sediment transport rate as sediment concentration increases. The model is then applied to turbidity currents in the Guxian Reservoir planned for middle Yellow River, China, which connects to a tributary featuring hyperconcentrated sediment-laden flow. The non-Newtonian model predicts slower propagation of turbidity currents and more significant bed aggradation at the confluence between the tributary Wuding River and the Yellow River in the reservoir than its Newtonian counterpart. This difference in model performance could be of considerable importance when optimizing reservoir operation schemes.
3. Scour hole reduction at a diversion channel junction using different entrance edge shapes
Ahmed Yahya ABDULHAFEDH · Nashwan Kamalaldeen ALOMARI ·
Ahmed Mohammed Sami AL-JANABI
Pages 811-820
https:/irtces/doi.org/10.1016/j.ijsrc.2023.07.001
Abstract: In the current study, the effect of the entrance edge shape on the scour hole in the diversion junction region was experimentally investigated. The investigation has considered three entrance models-rounded edge shapes on one or both sides of the diversion channel entrance-with five different inlet edge radius ratios (rr) of 25%, 37.5%, 50%, 62.5%, and 75% and five different diversion discharge ratios (Qr) of 7.5%, 12.5%, 17.5%, 22.5%, and 30%. The results have found the direct relation between Qr and the scour depth to the diversion channel water depth ratio (ds/yb). Moreover, the use of a rounded edge shape on one or both sides of the diversion channel entrance instead of a sharp shape results in a reduction in scour depth to diversion channel water depth ratio (ds/yb) when the Qr is greater than 20%. The results also indicated that the largest decrease in the scour coefficient (Kds) for the model with a rounded downstream edge compared with the sharp edge diversion channel entrance shape was 22% at a discharge ratio of 22.5% and an edge radius ratio of 37.5%. In addition, the entrance shape model with a rounded edge at the upstream outperformed other models in scour reduction with an average of all experiments of 5.77%. Finally, empirical relations for estimating scour depth for different rounded edge models in terms of the effective dimensionless parameters were established with coefficients of determination (R2) of not less than 0.853.
4. Experimental study on the effect of hydrodynamic conditions on flocculation and settling properties of fine-grain sediment
Bismark ODUM · Chunyang XU · Yongping CHEN · Yinpeng YAO · Yan ZHOU
Pages 821-833
https:/irtces/doi.org/10.1016/j.ijsrc.2023.08.001
Abstract: The flocculation of cohesive sediment particles is a function of the collision efficiency of sediment particles, which is mainly influenced by local flow hydrodynamics. A detailed study on local hydrodynamic characteristics in a novel stirred tank was done to measure the flow field of a turbulent flow. Instantaneous flow velocity fields were obtained and processed, and the average flow field was computed. Particle image velocimetry (PIV) results measuring the hydrodynamic characteristics (expressed as turbulent kinetic energy (TKE), local dissipation rate of TKE, velocity gradient or shear rate, turbulent shear stress, etc.) were analyzed and discussed. Particle tracking and automated image processing techniques were utilized to analyze the impact of the hydrodynamic conditions on the floc and settling properties. The differences in floc properties under the two turbulent shear states (i.e., steady-state (SS) and unsteady-state (US)) hydrodynamic conditions were examined. The results show that floc size and floc size distribution (FSD) of pure kaolin clay flocs are significantly influenced by the local dissipation rate of TKE and the turbulent intensity states. The floc size, df, 84, at local dissipation rate of TKE of 11 × 10?4, 29 × 10?4, 44 × 10?4, 83 × 10?4, and 142 × 10?4 m2/s3 is 97, 108, 107, 124, and 150 μm, respectively. It was found that by increasing the local dissipation rate of TKE, the FSD was skewed left. The US shear condition generated larger flocs (and in higher proportions) relative to the SS condition. The settling velocity and flux settling velocities of flocs formed under SS conditions are higher than those formed under US conditions. The fractal dimension of SS flocs also is higher than the fractal dimension of US flocs. These results highlight a significant impact of the states of hydrodynamics on floc properties such as floc size and FSD as well as the settling and morphological properties of flocs.
5. Assessment of ecological risk for heavy metals in surface sediment of an urban river in a developing country
Md Saiful ISLAM · Md Humayun KABIR · Mir Mohammad ALI · Md Towhidul ISLAM · Asfi a NIGER · Md Humayun KABIR · Zulhilmi ISMAIL · Sujat AHMED · Khalid A. IBRAHIM · Abubakr M. IDRIS
Pages 834-846
https:/irtces/doi.org/10.1016/j.ijsrc.2023.07.002
Abstract: The speed of increasing threats to the riverine water resources makes it more critical to protect the health of Old Brahmaputra River ecosystems. The current study was done to investigate the concentrations, distributions, sources, and ecological risk of heavy metals in surface sediment from the Old Brahmaputra River, Bangladesh. Samples were collected from seven sites and analyzed with an inductively coupled plasma-mass spectrometer (ICP-MS). The results showed that mean concentrations (mg/kg) of heavy metals were in the order of nickel (Ni) (44.69) > chromium (Cr) (30.16) > lead (Pb) (19.31) > copper (Cu) (17.84) > cadmium (Cd) (3.94) > arsenic (As) (2.73). The contamination factor (CF), pollution load index (PLI), enrichment factor (EF), and geo-accumulation index (Igeo) indicated low to moderate contamination. Toxic unit analysis revealed that the studied metals from all stations posed low risk. The sediment of the study river was uncontaminated to moderately contaminated, posing a minimal ecological risk. Cd, Cr, Ni, and Pb originated from anthropogenic sources rather than geogenic sources, and caused the severity of contamination. In this regard, pollutant-based intensive monitoring of heavy metals and holistic ecological risk assessments are required to maintain a sound and healthy aquatic environment in the river.
6. Ensemble and optimized hybrid algorithms through Runge Kutta optimizer for sewer sediment transport modeling using a data pre-processing approach
Enes GUL · Mir Jafar Sadegh SAFARI · Omer Faruk DURSUN · Gokmen TAYFUR
Pages 847-858
https:/irtces/doi.org/10.1016/j.ijsrc.2023.07.003
Abstract: Uncontrolled sediment deposition in drainage and sewer systems raises unexpected maintenance expenditures. To this end, implementation of an accurate model relying on effective parameters involved is a reliable benchmark. In this study, three machine learning techniques, namely extreme learning machine (ELM), multilayer perceptron neural network (MLPNN), and M5P model tree (M5PMT); and three optimization approaches of Runge Kutta (RUN), genetic algorithm (GA), and particle swarm optimization (PSO) are applied for modeling. The optimization and ensemble hybridization approaches are applied in the modeling procedure. For the case of hybrid optimized models, the ELM and MLPNN models are hybridized with RUN, GA, and PSO algorithms to develop six hybrid models of ELM-RUN, ELM-GA, ELM-PSO, MLPNN-RUN, MLPNN-GA, and MLPNN-PSO. Ensemble hybrid models are developed through coupling the ELM and MLPNN models with the M5PMT algorithm. The data pre-processing approach is applied to find the best randomness characteristic of the utilized data. Results illustrate that the RUN-based hybrid models outperform the GA- and PSO-based counterparts. Although the MLPNN-RUN and MLPNN-M5PMT hybrid models generate better results than their alternatives, MLPNN-M5PMT slightly outperforms MLPNN-RUN model with a coefficient of determination of 0.84 and a root mean square error of 0.88. The current study shows the superiority of the ensemble-based approach to the optimization techniques. Further investigation is needed by considering alternative optimization techniques to enhance sediment transport modeling.
7. Robust low-rank learning multi-output regression for incipient sediment motion in sewer pipes
Mir Jafar Sadegh SAFARI · Shervin RAHIMZADEH ARASHLOO
Pages 859-870
https:/irtces/doi.org/10.1016/j.ijsrc.2023.08.004
Abstract: The existing incipient sediment motion models typically apply conventional regression methods considering either velocity or shear stress. In the current study, incipient sediment motion is analyzed through a simultaneous and joint analysis of velocity and shear stress using the robust low-rank learning (RLRL) multi-output regression technique. Moreover, the experimental data compiled from five different channels are utilized to develop a generic incipient sediment motion model valid for a channel of any cross-sectional shape. The efficiency of the developed method is examined and compared against the available conventional regression models. The experimental results indicate that the RLRL model yields better results than its counterparts. In particular, while cross-section specific models fail to provide accurate estimates for shear stress or velocity for other cross sections, the proposed model provides satisfactory results for all channel shapes. The better performance of the recommended approach can be attributed to the joint modeling of the shear stress and the velocity which is realized by capturing the correlation between these parameters in terms of a low rank output mixing matrix which enhances the prediction performance of the approach.
8. Characterization of the micro-interfacial interactions of heterogeneous particulate matter (fine-grained sediment and microplastics) with copper ions
Jing OU · Zhihe CHEN · Tung-Chiung CHANG
Pages 871-879
https:/irtces/doi.org/10.1016/j.ijsrc.2023.08.006
Abstract: Particulate matter, such as sediment and microplastics (MPs), in aqueous environments has comparable micro-interfacial characteristics. However, the micro-interfacial characteristics of heterogeneous particulate matter are complex and are not fully understood. In this study, micro-interfacial kinetics and the interactions governing copper (Cu) ion adsorption to PP–sediment were investigated using micro-interfacial characterization experiments and kinetic experiments for Cu ion absorption to sediment, polypropylene (PP), and PP–sediment particles. The results show that (1) a pseudo-second-order model can be used to accurately describe the micro-interfacial kinetics of Cu ion adsorption to PP–sediment, indicating that chemical adsorption dominates the process. For Cu, the adsorption capacity, qe, of PP–sediment is approximately 0.4808 mg/g, between that of sediment and PP. (2) Film diffusion is the rate-controlling process in the early adsorption stage. Intraparticle diffusion gradually becomes the controlling process as the film diffusion constant (kfd) decreases and the film diffusion model becomes less applicable, but intraparticle diffusion is weaker in the PP–sediment system than in the sediment-only system. (3) The applicability of the intraparticle diffusion model for Cu ion adsorption to PP–sediment in the later stage of adsorption is between that of the sediment and PP systems. Furthermore, the heterogeneous aggregation of sediment and PP affects the micro-interfacial interactions of both types of particulate matter. The current study contributes to a better understanding of the micro-interfacial interactions of heterogeneous particulate matter (such as fine-grained sediment and MPs) with heavy metal ions in aqueous environments.
9. Experimental study on flocculation and sedimentation characteristics of cohesive fine sediment measured using ultrasound in the Pearl River Estuary
Qinqin LIU · Xiaojian LIU · Jian CHEN · Peng HOU · Yong HE · Qisong WANG · Xiaowei ZHU · Qiang WANG · Huan GAO
Pages 880-890
https:/irtces/doi.org/10.1016/j.ijsrc.2023.09.001
Abstract: Flocculation-settling of cohesive fine sediment is the main cause of sediment deposition and changes in topography and geomorphology in estuaries. However, studies on estuary morphology have often focused on a single influencing factor, and sediment deposition characteristics under disturbances in sediment concentration, moisture content, and external forces have rarely been considered simultaneously. The authors propose an ultrasound-assisted flocculation-settling method to analyze the various factor affecting cohesive sediment. The current study examined the sedimentation patterns of cohesive sediment with a sediment content concentration of 30%–80% through ultrasound experiments. The results show that when the sediment concentration is 40%–50%, the best effect on flocculation and sedimentation is induced by ultrasound waves. The corresponding settling height at the clear-muddy water interface is 3.05–3.45 cm, and the settling rate is 0.161–0.173 cm/min. Finally, using ultrasound waves, a moisture content of the sediment concentration of 30%–80% was analyzed based on wet and dry conditions. Taking a sediment concentration of 50% as an example, the maximum values of the variation in the water contents of the upper, middle, and lower layers of the wet basis were 0.82%, 0.51%, and 0.37%, respectively, whereas those of the upper, middle, and lower layers of the dry basis were 4.77%, 1.07%, and 0.60%, respectively. Thus, the moisture content of dry and wet sediment varied as follows: Wupper > Wmiddle > Wlower. The current research results can provide a theoretical basis and technical reference for siltation in channels, harbors, and reservoirs; the evolution of submarine deltas and coastal beaches; transportation of fluid mud; and the treatment of hyper-concentrated sediment flows.
10. Index model equation analysis: A case study of the risk and source of inorganic contaminants in roadside uncontaminated soil of the Egi oil producing area, Niger Delta
Elechi OWHOEKE · Asmat ALI · Okorondu Justin NNAEMEKA · Kingsley John ORIE · Julius Nkeonyeasua EHIWARIO · Abdur RASHID
Pages 891-900
https:/irtces/doi.org/10.1016/j.ijsrc.2023.07.004
Abstract: This study examined the sources, health risk and pollution status of selected inorganic contaminants such as iron (Fe), nickel (Ni), cadmium (Cd), cobalt (Co), arsenic (As), manganese (Mn), lead (Pb), copper (Cu), zinc (Zn), and chromium (Cr) in representative roadside uncontaminated soil (n = 72) from the Egi crude oil mining areas (Oboburu, Obagi, and Ogbogu), Niger Delta, Nigeria, using a combination of multiple models (Principle component analysis (PCA), correlation analysis, geo-accumulation index (Igeo), contamination factor (CF), enrichment factor (EF), pollution load index (PLI), cancer risk (CR), hazard quotient (HQ), and metal daily intake (MDIm)). A random sampling method was applied in the sampling and analysis using inductively coupled plasma mass spectroscopy. The result revealed that the mean (mg/kg) for Oboburu, was the highest for Fe (89.95 ± 28.83) and Mn (26.12 ± 7.642), whereas Obagi, had less Fe (28.90 ± 7.601) and Mn (16.80 ± 5.021), and Ogbogu, Fe (44.67 ± 28.15) and Pb (19.38 ± 8.731) was the second highest heavy metal. The order of contamination was F > Mn > Zn > Pb > Cu > Cr > Ni > Cd > Co. The Igeo and CF had cadmium as a metal of concern. The contamination level was low from the PLI estimation. The EF revealed anthropogenic sources for all the metals except for Ni, which was biogenic. The correlations at p < 0.05 and p < 0.01 showed much positive significance amongst the metals. Variations of the cumulative percentages, loading percentages, and eigenvalues from the regression plot gave a coefficients of determination (r2) of 0.9936, 0.9995, and 0.9994, respectively. The PCA indicated that Cd and Ni were of anthropogenic origin; Mn, Fe, and Co were biogenic or natural, and Zn and Pb were of mixed origins. The CR assessment indicated a possible cancer risk due to Cr, Cd, and Ni, and the rest of elements have no carcinogenic risk. These findings suggest there should be regular monitoring, source control, and integrated environmental management of the study area.
11. Establishment and development of the World Association for Sedimentation and Erosion Research
Cheng LIU · Zhaoyin WANG · Des E. WALLING
Pages 901-909
https:/irtces/doi.org/10.1016/j.ijsrc.2023.09.003
Abstract: Problems of soil erosion and sedimentation are issues of global concern. With the intensification of global change and the impacts of human activities, many countries are facing severe challenges from wide-ranging sediment-related problems. The prevention and control of sediment disasters and the rational use of soil and sediment resources are important requirements for the sustainable development strategies of all countries. As sediment problems are closely related to social, economic, and other human activities, the effective solution of sediment problems requires the concerted efforts of experts in different fields and thus an interdisciplinary approach is essential. In view of the increasing recognition of sediment as a topic of global significance and the need to promote interdisciplinary research in this field, the World Association for Sedimentation and Erosion Research (WASER) was inaugurated in 2004. In this paper the history of the establishment of WASER is reviewed and its main activities are briefly summarized. The series of International Symposia on River Sedimentation (ISRS) has served as the official symposium of WASER since 2004. These triennial technical events have been held in China, Russia, Japan, South Africa, and Germany with about 2,000 participants. In addition to sponsoring the ISRS, WASER has to date also sponsored/organized or co-sponsored/co-organized over 30 other international conferences, workshops, training courses, and study tours besides sponsoring the ISRSs. The adoption of the International Journal of Sediment Research (IJSR) as the official journal of WASER in 2004 has also played an important role in increasing the exposure of the Association. These activities have served to raise WASER's profile as well as promoting collaboration with agencies and other organizations working in the field of erosion and sedimentation. Three types of prizes and honors are awarded by WASER. These include the International Qian Ning Prize for Erosion and Sedimentation Technology, the IJSR Award for Distinguished Contributions to Sediment Research and Honorary Membership. Through its activities, WASER aims to strengthen the development of education and capacity building in the field of sustainable sediment management in global water management, promote sharing of information, on related data, the results of scientific research, and management methods, and advances in the study of erosion and sedimentation.
