International Journal of Sediment Research最新文献

{"title":"Relation between bank erosion and bed incision in the braided reach of the Lower Yellow River undergoing channel degradation","authors":"Junqiang Xia ,&nbsp;Yifei Cheng ,&nbsp;Meirong Zhou ,&nbsp;Xin Yu ,&nbsp;Xiangzhou Xu ,&nbsp;Koen Blanckaert ,&nbsp;Zhengbing Wang","doi":"10.1016/j.ijsrc.2024.12.002","DOIUrl":"10.1016/j.ijsrc.2024.12.002","url":null,"abstract":"<div><div>A general increase in the bankfull width and depth is found in downstream reaches because of upstream damming, especially in the braided reach of the Lower Yellow River (LYR), but the magnitude of bank erosion and its relation with bed incision remain little explored. Here based on long-term measured cross-sectional profiles (1999–2020), a quantitative method is proposed to estimate the bank erosion volume in the braided reach of the Lower Yellow River, with the contribution of bank erosion to the channel scour volume further determined. A quantitative relation was developed and calibrated between bank erosion width and bed incision depth, using the sediment continuity equation and measured data. The results indicate that: (i) significant bank erosion and bed incision processes are prevalent in the braided reach and its sub-reaches, with the bankfull widths increasing by 317–511 m and the bankfull depths increasing by 1.9–2.4 m in these reaches after the operation of the Xiaolangdi (XLD) Reservoir in 1999. Bank erosion has been dominant over bank accretion at more than 71% of the sections in the braided reach, with the most active bank deformation detected in the middle sub-reach. (ii) The cumulative bank erosion volumes temporally increased and spatially decreased, with the value of 1.80×10⁸ m³ in the upper sub-reach (R1), 1.52×10⁸ m³ in the middle sub-reach (R2), 1.08×10⁸ m³ in the lower sub-reach (R3), and 4.40×10⁸ m³ in the whole braided reach during the period of 1999–2020. Bank erosion contributed 33% of the cumulative channel scour volume in the braided reach, with a close relation developed between cumulative bank erosion volume and the previous 5-year average incoming sediment coefficient during flood seasons. (iii) A close inverse relation exists between bank erosion and bed incision in the whole braided reach and its sub-reaches, with the coefficients of determination greater than 0.90, which indicated that bank erosion hindered the process of bed incision. If there was no bank erosion after 1999, the cumulative bed incision depth would increase by at least 0.7 m in each reach. Furthermore, a similar quantitative relation was also applied to calculate the cumulative bed incision depth and bank erosion width in the braided reach during the period of 1960–1964 (the first stage after operation of the Sanmenxia Reservoir). Quite high accuracy was achieved in this analysis, with the coefficient of determination being equal to 0.96.</div></div>","PeriodicalId":50290,"journal":{"name":"International Journal of Sediment Research","volume":"40 2","pages":"Pages 241-252"},"PeriodicalIF":3.5,"publicationDate":"2024-12-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143601178","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Assessment of soil erosion dynamics and implications for sustainable land management: A case study using the RUSLE model","authors":"Lu Zhang ,&nbsp;Muhammad Haseeb ,&nbsp;Zainab Tahir ,&nbsp;Aqil Tariq ,&nbsp;Khalid F. Almutairi ,&nbsp;Walid Soufan","doi":"10.1016/j.ijsrc.2024.12.001","DOIUrl":"10.1016/j.ijsrc.2024.12.001","url":null,"abstract":"<div><div>The current research aimed to evaluate the severity and distribution of soil erosion in a Swat district, Pakistan, which is vital for sustainable land management and conservation efforts. This study focused on key parameters affecting soil erosion: the length factor (<em>L</em>), slope factor (<em>S</em>), crop management factor (<em>C</em>), rainfall erosivity factor (<em>R</em>), soil erodibility factor (<em>K</em>), and support practice factor (<em>P</em>). Various parameters were quantified via RS data from Sentinel-2 imagery and processed with geographical information system (GIS) tools. The values of these parameters ranged from 0.00% to 38.86%, 0 to 1, 547 to 773 <span><math><mtext>MJ</mtext><mo>·</mo><mtext>mm</mtext><mo>·</mo><msup><mtext>ha</mtext><mrow><mo>−</mo><mn>1</mn></mrow></msup><mo>·</mo><msup><mtext>year</mtext><mrow><mo>−</mo><mn>1</mn></mrow></msup><mtext>,</mtext></math></span> 0.24–0.33 <span><math><mtext>MJ</mtext><mo>·</mo><mspace></mspace><mtext>mm</mtext><mo>·</mo><msup><mtext>ha</mtext><mrow><mo>−</mo><mn>1</mn></mrow></msup><mo>·</mo><msup><mtext>year</mtext><mrow><mo>−</mo><mn>1</mn></mrow></msup></math></span> and 0.10–1.00, respectively. On the basis of these estimates, the total annual potential soil loss was approximately 173,816 <span><math><mi>t</mi><mo>·</mo><msup><mtext>ha</mtext><mrow><mo>−</mo><mn>1</mn></mrow></msup><mo>·</mo><mspace></mspace><msup><mtext>year</mtext><mrow><mo>−</mo><mn>1</mn></mrow></msup></math></span> with extreme erosion rates exceeding 10,000 <span><math><mrow><mi>t</mi><mo>·</mo><msup><mtext>ha</mtext><mrow><mo>−</mo><mn>1</mn></mrow></msup><mo>·</mo><msup><mtext>year</mtext><mrow><mo>−</mo><mn>1</mn></mrow></msup></mrow></math></span> in specific locations. The study categorized the soil erosion risk into five classes, ranging from very low to extreme, enabling the identification of areas requiring immediate attention and intervention. The findings of this study provide valuable insight for land management and conservation planning while also contributing to the United Nations’ Sustainable Development Goal 2 (Zero Hunger) by identifying areas where soil erosion poses a significant threat to food security. The current study underscores the importance of addressing soil erosion to promote sustainable land use and conservation strategies, ensuring long-term agricultural productivity and environmental health.</div></div>","PeriodicalId":50290,"journal":{"name":"International Journal of Sediment Research","volume":"40 3","pages":"Pages 385-399"},"PeriodicalIF":3.5,"publicationDate":"2024-12-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143932155","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Particle size and settling velocity of bed and suspended sediments for mud-sand beds","authors":"Leo van Rijn ,&nbsp;Luitze Perk ,&nbsp;Bas van Maren ,&nbsp;Andy Manning","doi":"10.1016/j.ijsrc.2024.11.007","DOIUrl":"10.1016/j.ijsrc.2024.11.007","url":null,"abstract":"<div><div>The particle size and the settling velocity of sediments are key parameters in sediment transport studies. However, it remains surprisingly difficult to determine particle size and settling velocity distribution of fine-grained sediments (mud-sand). A large range of methodologies exist to measure either the particle size distribution or to measure the settling velocity. An important influential parameter is the shape of fine-grained sediments, with clay minerals being shaped as plates rather than as spheres. Furthermore, the settling velocity of fine particles is influenced by turbulent shear and flocculation processes. Sometimes, the sediment samples are pre-treated (destroying inter-particle bonds) to measure the primary particle sizes involved while in other cases samples are not pre-treated in order to represent the effect of flocs. As a result, a large uncertainty exists in the way particle size and settling velocity should be measured. A range of methodologies (sedimentation, video camera, and laser-diffraction) to measure the settling velocity and particle size distribution in the field and in the laboratory is used and compared. The labour-intensive sedimentation methods measure a particle size distribution which can be used for sedimentation studies. The particle size distribution measured by the most commonly applied laser diffraction method is representative of the plate diameter of the clay particles, but the corresponding settling velocity is not correct. This difference can be explained by the shape of the clay particles through a derivation of the settling velocity of non-spherical particles resulting in a simple relationship to convert the particle size measured by laser diffraction to a representative particle size to be used in sedimentation studies. A comparison of the settling velocity measured by an <em>in situ</em> settling method and by a video camera method shows good agreement for high concentrations (&gt; 2000 mg/L) but deviating results for low concentrations (&lt; 500 mg/L).</div></div>","PeriodicalId":50290,"journal":{"name":"International Journal of Sediment Research","volume":"40 2","pages":"Pages 369-382"},"PeriodicalIF":3.5,"publicationDate":"2024-12-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143601819","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"TOC","authors":"","doi":"10.1016/S1001-6279(24)00113-6","DOIUrl":"10.1016/S1001-6279(24)00113-6","url":null,"abstract":"","PeriodicalId":50290,"journal":{"name":"International Journal of Sediment Research","volume":"39 6","pages":"Pages ii-iii"},"PeriodicalIF":3.5,"publicationDate":"2024-11-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142662611","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Impact of emergent vegetation on three-dimensional turbulent flow properties and bed morphology in a partially vegetated channel","authors":"Pritam Kumar,&nbsp;Anurag Sharma","doi":"10.1016/j.ijsrc.2024.10.006","DOIUrl":"10.1016/j.ijsrc.2024.10.006","url":null,"abstract":"<div><div>The study aimed to explore three-dimensional turbulent flow properties and bed morphology in a partially vegetated channel with sand bed conditions. Presence of flexible vegetation in the river and its interaction with the flow are of great significance in understanding the momentum and mass transport in the flow. Experiments were conducted in a straight, tilting rectangular flume with staggered emergent vegetation covering half of the channel width. The results show that the presence of vegetation diverts streamwise velocity from the vegetated side to the non-vegetated side. The study reveals that the presence of vegetation leads to an increase in turbulent intensity, turbulent kinetic energy, and Reynolds shear stress at the transition area between the vegetated and non-vegetated sides of the channel. This increase is attributed to higher transverse flow and momentum exchange in the transition area between the vegetated and non-vegetated sides. In the vegetated side, the vegetation serves as an obstruction, reducing turbulent intensity, turbulent kinetic energy, and Reynolds shear stress compared to the transition area between the vegetated and non-vegetated sides. This reduction in turbulence supports the stability of bed materials and promotes sediment deposition. The presence of vegetation significantly alters the secondary current in the channel. Scour depth along the non-vegetated side was higher than the vegetated side, mainly because the flow concentrated in the centre and non-vegetated side of the channel. The investigation determines that the existence of vegetation on the vegetated side effectively protects against bed erosion and sediment transport. Understanding the impact of emergent flexible vegetation on flow properties and sediment transport can inform decisions about vegetation layouts in river ecosystems.</div></div>","PeriodicalId":50290,"journal":{"name":"International Journal of Sediment Research","volume":"40 2","pages":"Pages 286-311"},"PeriodicalIF":3.5,"publicationDate":"2024-10-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143601181","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of submerged vegetation on hydraulic resistance of ice-covered flows","authors":"Sanaz Sediqi,&nbsp;Jueyi Sui,&nbsp;Guowei Li","doi":"10.1016/j.ijsrc.2024.09.008","DOIUrl":"10.1016/j.ijsrc.2024.09.008","url":null,"abstract":"<div><div>Understanding the hydraulic resistance is vital for river engineering projects that include the installation of in-stream infrastructure, such as bridge abutments, which directly impact flow dynamics and sediment transport. In this study, based on laboratory experiments in a large-scale flume, the hydraulic resistance of flow has been investigated, considering the combined effects of submerged vegetation, ice cover, and bed sediment. The bed and ice cover shear stress, vegetative drag, and the composite Manning's roughness coefficient under various conditions have been calculated and discussed. An empirical model that indicates the relationship between the composite Manning's roughness coefficient of the channel and the roughness coefficients of the bed, ice cover, and vegetation has been developed. Results indicated that the presence of an ice cover leads to a noticeable increase in the channel bed shear stress, with a greater contribution of the shear stress in vegetated beds under ice-covered flow conditions, accounting for up to 60% of the total shear stress compared to that under open flow conditions with vegetated beds. Compared to the square arrangement of vegetation elements in the bed, the presence of vegetation arranged in a staggered pattern in the bed results in a decrease in the bed shear stress but an increase in the vegetation drag force. Findings emphasize the importance of vegetation density as the primary factor influencing the drag coefficient. Notably, the drag force exceeds the shear force in all experimental scenarios, accounting for 85% of the total resistance force. Furthermore, Manning's roughness coefficient for the vegetation patch exhibits higher values than that for the ice cover. A clear correlation exists between Manning's coefficients and the Froude number; the higher the flow Froude number, the less the Manning's roughness coefficient.</div></div>","PeriodicalId":50290,"journal":{"name":"International Journal of Sediment Research","volume":"40 2","pages":"Pages 348-368"},"PeriodicalIF":3.5,"publicationDate":"2024-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143601818","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Potential reuse of fine sediment from hydroelectric dams and recycled concrete sand in road subgrades","authors":"Hamza Beddaa ,&nbsp;Saannibe Ciryle Somé ,&nbsp;Amor Ben Fraj ,&nbsp;Coryse Coudray ,&nbsp;Emmanuel Branche ,&nbsp;Amaury Cudeville","doi":"10.1016/j.ijsrc.2024.09.004","DOIUrl":"10.1016/j.ijsrc.2024.09.004","url":null,"abstract":"<div><div>Hydroelectric dams play a crucial role in power generation, water storage, and irrigation. However, their continuous operation has led to sediment accumulation, thereby reducing the water storage capacity and impacting the facility's life span. The aim of the current study is to assess the reuse potential of dredged fine sediment in the composition of road subgrades. Nine types of sediment from diverse hydroelectric dams are analyzed for their chemical, environmental, physical, and geotechnical properties. These sediments then were treated with quicklime and a slag-based hydraulic road binder (3% and 6%, respectively). The current investigation involves evaluating: Proctor parameters, the immediate bearing index, treatment ability, and the mechanical properties of the treated sediment. The results reveal that the properties of treated sediment differ from one mixture to another, thus, indicating that some mixtures meet the criteria outlined in the French Roadworks Guide, by virtue of their clay and organic matter contents. Moreover, the current study explores the impact of incorporating recycled concrete sand (RCS) as a granular corrector to enhance the reuse potential of the sediment in road subgrades. The current findings indicate that adding RCS significantly improves mixture properties, particularly mechanical characteristics, by reaching 1 MPa before 7 days of curing. These promising outcomes pave the way for more advanced road construction practices in ensuring environmental compliance and promoting an eco-friendly reuse of sediment.</div></div>","PeriodicalId":50290,"journal":{"name":"International Journal of Sediment Research","volume":"39 6","pages":"Pages 971-983"},"PeriodicalIF":3.5,"publicationDate":"2024-09-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142662610","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Biogenic “phosphorus” effect of terrestrial lakes and its significance to oil shale during the Carnian period in the late Triassic","authors":"Jiyuan You ,&nbsp;Xiaohu Zhou ,&nbsp;Yiyao Yang ,&nbsp;Shanshan Song ,&nbsp;Yiqun Liu ,&nbsp;Zhengzhong Liang ,&nbsp;Yunyun Bai","doi":"10.1016/j.ijsrc.2024.09.006","DOIUrl":"10.1016/j.ijsrc.2024.09.006","url":null,"abstract":"<div><div>The Triassic lacustrine organic-rich shale (LORS) in Member 7 of the Yanchang Formation (Carnian stage) in the southern Ordos Basin is relatively well developed. Additionally, its organic matter abundance, lake biomass and biodiversity, exceed the maximum values of the other strata deposited during the same period. Apatite is one of the most important minerals and is closely related to biological activities. However, the types and genesis of the continental sedimentary apatite and its significance to shale oil are not clear. Here, the stratigraphy, petrology, and sedimentology of the phosphorus-bearing rock series in the Ma Quan section are studied and its sedimentary environment and phosphorus formation are discussed. The current research shows that apatite in the study area can be divided into three categories: collophanite, bone fossils, and spherical microfossils. These three types of biogenic “phosphorus” products provide effective records of the transformation of the biological substances into sedimentary organic matter. There are two main formation mechanisms: the direct action of organisms and the interaction between the organisms. Bone fossils and spherical microfossils are formed by the direct action of organisms, while collophanite is formed by the indirect action of organisms. The phosphatization methods of the organisms mainly include “coating”, “replacement”, and “filling”, and the presence of a ubiquitous phosphate filler potentially reflects a sufficient phosphate supply. Apatite also is highly important for the development of organic matter in oil shale. First, it changes the productivity conditions. Second, the apatite in the shell of spherical microfossils has a certain protective effect on the organic matter in the inner cavity. In the current study, the geological processes of collophanite deposition and mineralization are explained, an important basis for prospecting phosphate resources is provided, and a new field for the study of the organic matter enrichment mechanism of source rocks is established. At the same time, the process of lake biogenic phosphorus formation provides evidence from the continental deposits in the eastern margin of the Tethys region for exploring deep global changes.</div></div>","PeriodicalId":50290,"journal":{"name":"International Journal of Sediment Research","volume":"39 6","pages":"Pages 960-970"},"PeriodicalIF":3.5,"publicationDate":"2024-09-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142662599","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Quantification of bedload transport in the Hungarian Danube using multiple analysis methods","authors":"Sándor Baranya","doi":"10.1016/j.ijsrc.2024.09.005","DOIUrl":"10.1016/j.ijsrc.2024.09.005","url":null,"abstract":"<div><div>While bedload transport is crucial to river morphodynamics, quantifying it in large rivers, such as the Danube, poses significant challenges. The current study focuses on the gravel-dominated section of the Danube River in Hungary, where multiple methods have been concurrently applied to evaluate bedload transport. In a representative cross section of the river, the following methods were applied: (i) point-wise direct physical sampling using a BfG-type pressure difference sampler, quality controlled with a video camera mounted on the sampler; (ii) indirect acoustic-based analysis with an Acoustic Doppler Current Profiler (ADCP), evaluating the Bottom Tracking signal; and (iii) indirect acoustic and imaging-based method utilizing Acoustic Mapping Velocimetry (AMV). The ADCP method is calibrated using results from the physical sampling, while the AMV method relies on bedform tracking and is entirely independent from the two other techniques. The results from a series of measurement campaigns, covering a wide range of flow regimes, suggest a robust bedload rating curve for the study section, enabling the estimation of bedload yields and its relation to morphological changes. In addition, the applicability conditions of the implemented methods are discussed.</div></div>","PeriodicalId":50290,"journal":{"name":"International Journal of Sediment Research","volume":"39 6","pages":"Pages 1015-1026"},"PeriodicalIF":3.5,"publicationDate":"2024-09-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142662572","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Response of tenuous clay-polysaccharide flocs to hydrodynamic shearing","authors":"Li He ,&nbsp;Hang Yin ,&nbsp;Yongkang Wu ,&nbsp;Wei Sun ,&nbsp;Guoping Zhang","doi":"10.1016/j.ijsrc.2024.08.004","DOIUrl":"10.1016/j.ijsrc.2024.08.004","url":null,"abstract":"<div><div>The response of suspended tenuous clay-polysaccharide flocs to hydrodynamic shearing was investigated in the laboratory via particle size analyses to understand the molecular-scale interactions between clay minerals and polysaccharides and their hydrodynamic behavior such as size kinetics, re-flocculation/breakdown, and shear strengths of the hybrid flocs. While the studied suspensions had a fixed clay concentration of 0.4 g/L, an array of other parameters was varied to reflect the complexity of clay-polysaccharide systems, including four types of clay minerals with varying layer charges and swellability (i.e., kaolinite, illite, and sodium- (Na-) and calcium- (Ca-) montmorillonites), two exopolymers of dissimilar polarities (i.e., xanthan and guar), six polysaccharide (<em>P</em>) to clay (<em>C</em>) weight ratios (i.e., <em>P</em>/<em>C</em> = 0, 1, 2, 5, 10, and 20 wt%), and three hydrodynamic shearing rates of 187, 429, and 1,100 1/s (i.e., corresponding to laminar, transitional, and turbulent flows, respectively). Results show that the clay-polysaccharide floc sizes are sensitive to the shear stress and also vary with different clay-polysaccharide systems. Four discrete particle groups were identified by statistical analyses, consisting of primary particle (PP), flocculi (FL), microfloc (MiF), and macrofloc (MaF), which exhibit distinct stabilities to shearing. The MaF is much weaker than MiF and can easily breakdown, as indicated by the decrease in MaF fraction with increasing shearing, while the MiF is the dominant particle group in transitional and turbulent flows. The fractions of PP and FL generally increase with shearing rate. Based on floc survivability in different flow conditions, the MaF's upper and lower bound shear strengths were estimated to be 0.95 and 0.17 Pa, respectively. The strongest MaF with a maximum shear strength of 0.95 Pa is formed in the clay-guar suspensions at a <em>P</em>/<em>C</em> of 10 wt%. Anionic xanthan only forms flocs with kaolinite with little surface charges, but cannot induce clay-polysaccharide flocs for illite and Ca/Na-montmorillonite with negative surface charges due to electrostatic repulsion. In contrast, neutral guar generates flocs with all 4 clay minerals due to the formation of hydrogen bonds, and MaF compounds usually are absent in turbulent flow (except kaolinite with a small fraction of MaF). These results further demonstrate the essential role of polysaccharide's polarity in dictating the flocculation dynamics, and, hence, sediment transport behavior. Practical implications of the findings are discussed in terms of the emerging technological applications of clay-polymer systems as well as the transport and modeling of natural aquatic cohesive sediment in biofilm-bearing waters.</div></div>","PeriodicalId":50290,"journal":{"name":"International Journal of Sediment Research","volume":"39 6","pages":"Pages 984-997"},"PeriodicalIF":3.5,"publicationDate":"2024-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142662560","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}