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The tail river channel serves as a critical zone for the interaction between rivers and oceans, holding significant ecological and environmental implications. This study employs a physical experimental approach to simulate the evolution processes of common trumpet-shaped and meander-shaped (left- bending and right- bending at the estuary) tail river channels. The research investigates the morphological evolution patterns under varying water and sediment conditions. Evaluation of different river types′ stability is based on coefficient of fluvial facies and relative roughness. The experiments reveal that the planar morphology of the river undergoes stages of “ stabilitymicro- change- strong change. ” The average elevation and slope of the riverbed increase over time, with the most significant changes occurring in the upstream and estuary sections and the least in the midstream. Sediment addition results in upstream riverbank erosion and riverbed sedimentation. Following cessation, downstream and estuary sections experience more pronounced riverbank erosion than riverbed erosion, leading to estuarine bifurcation, oscillation, and shifting. The unstable areas in planar morphology are the downstream section for meander- shaped channels and the estuary section for trumpet-shaped channels, with significant differences in river phase coefficients. For cross-sectional morphology, the downstream section is unstable for left-bending meander-shaped channels (with a more than 3-fold difference in relative roughness), the upstream section for right- bending meander-shaped channels (more than a 2. 03-fold difference in relative roughness), and the downstream section for trumpet-shaped channels (more than a 4. 09-fold difference in relative roughness). [ABSTRACT FROM AUTHOR]

Copyright of Advances in Water Science / Shuikexue Jinzhan is the property of Editorial Board of Advances in Water Science and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Harbour Engineering is the property of Editorial Office of China Harbour Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Remote Sensing for Natural Resources is the property of Remote Sensing for Natural Resources Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Rural Water & Hydropower is the property of China Rural Water & Hydropower Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The maximum sediment transport capacity of river channel is affected by hydrodynamic force, resistance and boundary conditions. Based on the hydraulic radius segmentation method, the isosceles trapezoid with the bank slope angle θ was adopted as the water crossing section, and the relative roughness of the river bank to the bottom（λ）,the median particle size of the transported sediment(d50),the roughness of the bed sediment (nb), the discharge (Q), and the gradient (S) were taken into account. The impact of each influencing factor on the maximum sediment transport capacity and equilibrium form of the channel when the alluvial river reaches the equilibrium state was analyzed with the river equilibrium theory. The results show that: when other factors are fixed, the maximum sediment transport rate increases with the increase of λ and decreases with the increase of θ; That is to say, the relative increase of river roughness or the decrease of river slope will enhance the maximum sediment transport capacity of river channel. The increase of Q and S leads to higher river dynamics, thus enhancing the sediment transport capacity of the channel. The maximum sediment transport capacity of the channel will be reduced when the bottom roughness coefficient nb decreases and the flow remains unchanged; The decrease of the median particle size d50 of bed sediment will increase the maximum sediment transport capacity of the river. The channel which is neither too wide and shallow nor too narrow and deep has the maximum sediment transport capacity. [ABSTRACT FROM AUTHOR]

Low-slope bedrock meandering rivers widely exist in areas controlled by geological structures (the bed slope is less than 5‰). Flood has a great influence on riverbed sedimentation and erosion in bedrock meandering rivers, however, we have a poor understanding of dynamic structure of flood for bedrock meandering rivers. By geometrically generalizing bedrock meandering reaches, considering the Froude similarity and side wall roughness, a generalized model of a bedrock meandering channel is established in order to analyze the water surface profile distribution, time average flow fields and turbulence structure characteristics for bends under flood. The results show that under the flood flow, the minimum water surface transverse gradient, separation of flow on the convex bank, development of double circulation on the concave bank, velocity-dip-phenomenon and maximum secondary circulation intensity are caused at the upstream of the bend apex, and the maximum water surface transverse gradient and circulation splitting are caused at the downstream of the bend apex; the bed shear stress is distributed in the flow separation area at the convex bank as well as the center of the upstream of the bend apex, and the transverse momentum transport is concentrated at the upstream of the bend apex. The experiment results show an explanation in view of hydrodynamics in respect to bed erosion and sedimentation in bedrock meandering rivers. [ABSTRACT FROM AUTHOR]

Copyright of Yellow River is the property of Editorial Board of Yellow River and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Ｓｅｄｉｍｅｎｔ ｉｓ ｃａｒｒｉｅｄ ｂｙ ｆｌｏｗ ｔｏ ｔｈｅ ｌａｋｅ ａｒｅａ ｄｕｒｉｎｇ ｔｈｅ ｆｏｒｍａｔｉｏｎ ｐｒｏｃｅｓｓ ｏｆ ｔｈｅ ｉｎｉ⁃ ｔｉａｌ ｓｅｇｍｅｎｔ ｏｆ ａ ｄｅｌｔａ， ｗｈｉｃｈ ｍａｉｎｌｙ ｄｅｐｅｎｄｓ ｏｎ ｔｈｅ ｉｎｉｔｉａｌ ｍｏｍｅｎｔｕｍ ｔｏ ｍａｉｎｔａｉｎ ｉｔｓ ｏｗｎ ｃｏｎ⁃ ｔｉｎｕｏｕｓ ｍｏｖｅｍｅｎｔ． Ａｃｃｏｒｄｉｎｇ ｔｏ ｔｈｅ ｃｈａｒａｃｔｅｒｉｓｔｉｃｓ ｏｆ ｔｈｉｓ ｐｒｏｃｅｓｓ， ｔｈｅ ｔｈｅｏｒｅｔｉｃａｌ ｍｏｄｅｌ ｆｏｒ ｔｈｅ ｐｌａｎｅ ｊｅｔ ｂｏｕｎｄａｒｙ ｌａｙｅｒ ｉｎ ｔｈｅ ｉｎｉｔｉａｌ ｓｅｇｍｅｎｔ ｏｆ ｔｈｅ ｄｅｌｔａ ｗａｓ ｅｓｔａｂｌｉｓｈｅｄ ｂａｓｅｄ ｏｎ ｔｈｅ ｓｈａｌｌｏｗ ｗａｔｅｒ ｅｑｕａｔｉｏｎｓ ｆｏｒ ｍｕｄｄｙ ｗａｔｅｒ， ａｎｄ ｔｈｅ ｆｌｏｗ ｆｉｅｌｄ ｄｉｓｔｒｉｂｕｔｉｏｎ ｏｆ ｔｈｅ ｉｎｉｔｉａｌ ｓｅｇｍｅｎｔ ｏｆ ｄｅｌｔａ ｆｏｒｍａｔｉｏｎ ｗａｓ ｏｂｔａｉｎｅｄ ｗｉｔｈ ｔｈｅ ｓｉｍｉｌａｒｉｔｙ ｓｏｌｕｔｉｏｎ ｍｅｔｈｏｄ． Ｂａｓｅｄ ｏｎ ｔｈｅ ｇｅｎｅｒａｌ ｍａｔｈ⁃ ｅｍａｔｉｃａｌ ｍｏｄｅｌ ｏｆ ｒｉｖｅｒ ｂｅｄ ｅｖｏｌｕｔｉｏｎ， ｔｈｅ ｔｈｅｏｒｅｔｉｃａｌ ｅｘｐｒｅｓｓｉｏｎ ｏｆ ｔｈｅ ｍｏｒｐｈｏｌｏｇｉｃａｌ ｃｈａｒａｃ⁃ ｔｅｒｉｓｔｉｃｓ ｏｆ ｔｈｅ ｉｎｉｔｉａｌ ｓｅｇｍｅｎｔ ｗａｓ ｄｅｒｉｖｅｄ， ａｎｄ ｔｈｅ ｅｒｏｓｉｏｎ ａｎｄ ｄｅｐｏｓｉｔｉｏｎ ｏｆ ｔｈｅ ｉｎｉｔｉａｌ ｓｅｇｍｅｎｔ ｗｅｒｅ ｑｕａｎｔｉｔａｔｉｖｅｌｙ ａｎａｌｙｚｅｄ． Ｔｈｒｏｕｇｈ ｔｈｅ ｅｘｐｅｒｉｍｅｎｔａｌ ｖｅｒｉｆｉｃａｔｉｏｎ， ｔｈｅ ｔｈｅｏｒｅｔｉｃａｌ ｓｏｌｕｔｉｏｎ ｃａｎ ｗｅｌｌ ｄｅｓｃｒｉｂｅ ｔｈｅ ｅｒｏｓｉｏｎ ａｎｄ ｄｅｐｏｓｉｔｉｏｎ ｔｒｅｎｄ ａｎｄ ｍｏｒｐｈｏｌｏｇｉｃａｌ ｃｈａｒａｃｔｅｒｉｓｔｉｃｓ ｉｎ ｔｈｅ ｅａｒｌｙ ｓｔａｇｅ ｏｆ ｄｅｌｔａ ｆｏｒｍａｔｉｏｎ． [ABSTRACT FROM AUTHOR]

Copyright of Advances in Water Science / Shuikexue Jinzhan is the property of Editorial Board of Advances in Water Science and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Applied Mathematics & Mechanics (1000-0887) is the property of Applied Mathematics & Mechanics and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

We develop a numerical model that encompasses wave induced current as well as advective and diffusion models to examine the effects of Stokes drift on pollutant transport within the surf zone on a plane beach. We also carried out dye diffusion experiments in the surf zone, and modelled wave-induced currents by applying the concept of radiation stress. We based wave propagation on the equation of wave energy conservation, while the advective diffusion model, including Stokes drift, was used to describe pollutant transport in the surf zone. We then used the alternative direction implicit finite difference method to differentiate between models, and evaluated the validity of these numerical approaches using a Gaussian pulse with a known exact solution. The numerical results of this study are in close agreement with analytical solutions. Finally, we applied our model to simulate pollutant transport within the surf zone on a plane beach. Results show that numerical modeling including Stokes drift more closely agrees with experiments than do results that exclude this drift. Thus, in general, we show that a pollutant will be more obviously transported shoreward in addition to the extent of expected drift. We therefore suggest that Stokes drift plays an important role inpollutant drift within thesurf zone, especially in ashoreward direction. [ABSTRACT FROM AUTHOR]

Copyright of Applied Mathematics & Mechanics (1000-0887) is the property of Applied Mathematics & Mechanics and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)