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Sediment measurement is usually accessible on a periodic or distinct basis. The measurement of sediment (suspended and bedload), especially in the field, is vital in keeping essential data of sediment transport and deposition. Various techniques for measuring sediment have been used over time each with its merits and demerits. The techniques discussed in this paper for suspended sediment include bottle, acoustic, pump, laser diffraction, nuclear and optical. Other techniques for bedload measurement are; River bedload trap (RBT), CSU/FU bedload trap, Helley–Smith, Polish Hydrological Services (PIHM) device, pit and trough, vortex tube, radioactive traces and bedload–surrogate technologies. However, the choice of technique depends on multiple factors ranging from budget constraint, availability of equipment, manpower and data requirement. The purpose of this paper is to present valuable information on selected techniques used in sediment measurement, to aid researchers/practitioners in the choice of sediment measurement technique.

This paper presents a general review of selected field techniques used in sediment measurement (suspended and bedload). Each techniques mode of operation, merits and demerits are discussed.

This paper highlights that each technique has its peculiar merits and demerits. However, two techniques are generally preferred over others; the bottle sampling and the Helley–Smith sampler for measuring suspended and bedload sediment. This is because the applicability of these techniques is quite widespread and time-tested.

This review paper provides an in-depth description and comparison of selected existing field sediment measurement techniques. The objective is to ease decision-making about the choice of technique, as well as to identify the suitability and applicability of the chosen technique.

The change in sediment transport phenomenon and morphological characteristics of Kulfo River in the southern part of Ethiopia is estimated using one-dimensional hydraulic modelling. The purpose of this study is to predict erosion and sedimentation using hydrological engineering center-river analysis system (HEC-RAS) model.

Geometrical survey data of 2005 and 2019 were used to assess the impact of flood depth with 100 years of return per period on the morphology of the river. The bed and bank materials at selected sites of the river were sampled to estimate the grain size using manning roughness coefficient. Discharge and suspended sediment concentration were sampled thrice per day for a stretch of three months to develop a rating curve.

HEC-RAS model indicates that flood depth with 100 years return period had a significant inundated area during 2019 in comparison to 2005 demonstrating a temporary change in the morphology of the river. Acker and White method in HEC-RAS was used extensively to calculate the sediment load and subsequently calibrated. In the upper reach of the study area, there was aggradation and degradation, whereas the only degradation was noted in the middle to the downstream reach of the channel. Seasonal flood during peak flow due to a rise in bed level is most prevalent during the aggradation period.

Comparison of a flood depth inundating the catchment and sediment deposition has been intricately analyzed by using HEC-RAS model.

To study the impact of River Nestos (North Greece) dams construction on coastal morphology.

In order to study the evolution of the coastal morphology in the area, an “one‐line shoreline change model” was developed (PELNCON). The model's input comprises the field characteristics, the wave characteristics at the breaker line and a “source” term for the sediment supply rate by River Nestos. The model calculates the shoreline change over a given period of time. The annually transported sediment quantity by the river is estimated using filed measurements and other models' results for various sites along the Greek part of the hydrologic basin of Nestos (Nestos is a transboundary river extending along Greece and Bulgaria).

The “PELNCON” results demonstrate a serious erosion threat for the coastal area due to the sediment budget deficit of about 1.8 × 10⁶m³/year.

The developed model is subject to common structural weaknesses of computational modelling based on the one‐line shoreline change theory.

The developed model is user‐friendly and can be applied to any coastal area of known characteristics, providing realistic results.

This paper is an attempt to model the correlation between two large‐scale phenomena, namely coastal erosion and water/sediment management in river basins, setting at the same time the basis for further study on this particular scientific field.

Finer sediment particles (silt and clay) transported by rivers carry the major part of nutrient loads by absorption; thus, sediment settling can remove nutrients from the water column. The purpose of this paper is to analyze the relation between reservoir sedimentation and water quality by assessing the reservoir sedimentation process and the sediments’ characteristics.

Bathymetric surveys from 2004 to 2014 were analyzed to assess the sedimentation process. Core samples provided information on a layer-by-layer basis of the sediment deposits, and water samples near the surface and near the bottom provided information on sediment concentration, and adsorbed and dissolved nutrients.

The upstream region of a reservoir is already silted. From 2004 to 2014, the delta evoluted approximately 500 m downstream and the deposits were mainly composed of clay. An area of approximately 1,000 m between the delta and the dam should still be able to continue allowing sediment deposition in the coming years. Most of the nutrients were absorbed into the sediment particles, except for the nitrogen measured in the dry season.

Although analyses of the full cycle of the nutrients were not carried out, the constant sediment trapping of finer sediments and the high rate of absorbed nutrients in the suspended sediment support the hypothesis that the reservoir has removed nutrients from aqueous media by adsorption into sediments.

In the studied case, reservoir sedimentation has led to better water quality downstream.

It is shown in this study that reservoir sedimentation may have positive effects on river water quality.

This study aims to provide a review for scour in complex rivers and streams with coarser bed material, steep longitudinal bed slopes and dynamic environments, in the interest of the safety and the economy of hydraulic structures. The knowledge of scour in such geographical complexities is very crucial for a comprehensive understanding of scour failures and for establishing definitive criteria to bridge this major research gap.

The existing available literature shows significant work done in case of silt, sand and small sized coarser bed material but any substantial work for bed material of gravel size or above is lacking, resulting in a wide gap. Though some researchers have attempted to explore possibilities of refining the existing models by adding pier size, shape, sediment non-uniformity and armouring effects, which otherwise have been given a miss by the various researchers, including the pioneer in the field Lacey–Inglis (1930). But still, a rational model for scour estimation in such complex conditions for global use is yet to come. This is because all the parameters governing the scour have not been studied properly till date as is evident from the globally available literature and is witnessed in the field too, in recurrent failure of hydraulic structures especially bridges.

The researchers presume that the finer materials move only as a result of erosion. However, in actual field conditions, it has been observed that the large-sized stones also roll down and cause huge erosion along the river bed and damage the hydraulic structures, especially in the steep river/stream beds along hilly slopes. This fact has been overlooked in the models available globally and has been highlighted only in the current work in an attempt to recognize this major research gap. A study carried out on a number of streams globally and in Jammu and Kashmir, India also, has shown that in steep river and stream beds with bed material consisting of gravel size or greater than gravel, large scour holes ranging from 1 m to 5 m were created by furious floods, and due to other unknown forces along the channel path and near foundations of hydraulic structures.

To the best of the authors’ knowledge, this work is purely original.

The coast at Berakas in the Brunei-Muara district of Brunei Darussalam suffers from erosion caused by a combination of fluvial and marine processes. This paper investigates the rate and pattern of erosion along a 1.8-km stretch of coast to compare the difference between the unprotected and protected sections. We used (i) image and spatial analysis and (ii) field geomorphology. The Digital Shoreline Analysis System (DSAS) in ArcGIS was used to compare the study area using two Google Earth images. The study found that the unprotected section had receded by 4.6 m between 2009 and 2019, while the protected section had advanced by 8.0 m over the same period; intense gullying and slumping of cliff continued at both sections. The detached headland breakwaters in the protected section were effective in stabilizing the coast. A concrete drain installed parallel to the cliff edge appears to be capable of intercepting storm runoff, but its effectiveness was undermined by lack of maintenance. We conclude that terrestrial-fluvial processes continue to erode coastal land and cause slumping of the cliff face at Berakas. However, coastal protection structures that curb the marine process could stabilize the coastline, even where sediment transport is active.

The purpose of this paper is to construct a numerical model for the numerical analysis of the hydraulic transient profile in Trabalhador channel for filling and emptying maneuvers and to determine the water level in time. Model results support operational managers in the decision-making process.

Physical data were provided for the construction and calibration of the numerical model. The equations of Saint-Venant were approximated by a finite difference scheme and the numerical model was written in Fortran. The results of filling and emptying of the channel simulations were compared with the measured water levels.

Measured water levels and those simulated by the numerical model have shown good correlation. The time recorded for the filling and emptying of the canal was also close between the measured and simulated data. The simulation design flow pointed to inundation in the channel banks. Simulation water levels were slightly higher than those measured.

In this model, the combination of canals and pressure conduits was not considered.

The findings confirm the measured time for filling and emptying of the canal, as well as inundation of canal banks for the maximum design flow. These results help in the management process.

This paper presents a numerical model for hydraulic transient analysis in channels with good agreement with the field data.

The purpose of this paper is to analyse the results of particle size profiles carried out in the dam Mãe d’água, located in the metropolitan region of Porto Alegre, Rio Grande do Sul, becoming a tool of support for geochemistry evaluation works of sediments in this basin.

The methodology comprised the particle size analysis of eight cores sampled using the extraction profile technique “Sampling Cores.” A total of 56 sub-samples were obtained at different depths, varying between 0 and 52 cm. The particle size analysis of the sub-samples was carried out with the protocol relating to Brazilian analysis standards NBR 7,181; for determination of the particle size distribution of thick sediments, the sieve method was used, and for fine sediments, the pipette method was used.

The results show that for the different depths, the sediment profiles show similarity in their sedimentary deposition layers. Cores T1, T6, T7 and T8 showed a classification with predominance of mud. Cores T2 and T5 showed variations throughout their sedimentary profile, varying of mud predominance to sand with gravel, and on cores T3 and T4, the predominant characteristic is sand with mud and sand with gravel, respectively.

It can be seen in this paper that energy of sedimentological flow reaches it in a different way, creating these three sectors (first, sand with gravel; second, sand with mud and third, mud) with different characteristics – morphodynamic and sedimentological. These characteristics are important for the study of the heavy metals on the soil and therefore for reducing the risk of contamination of water courses.

Coastal sections suffering from erosion generally show the common symptom of a lack of available sand to allow the build up of the natural coastal barrier. Soft methods of coastal protection, including beach nourishment, profile nourishment, feeder berms, compensation‐dredging, aim to tackle the problem at its source, i.e. by supplying sand to the system. When thoroughly designed, these methods are considered the best technical/economical and appropriate solutions.

The purpose of this paper is to perform a comparative analysis between Aveiro's Lagoon (Portugal) and Sepetiba Bay (Brazil), in order to understand the similarities and differences between these two coastal zones, in terms of human occupation.

This paper is supported by works (papers and scientific projects being developed) produced in Portugal and Brazil, by researchers from different areas of expertise.

These two coastal zones have a similar geomorphologic evolution, due to the fact that both appeared because of a sandy spit, which started to grow and separated these areas from the sea, converting them into sheltered coasts. It was because they are protected that these two study cases early became targets for human occupation. The anthropic impacts in the systems were sustainable until the middle of the twentieth century. Since then, however, the economic development options, based first in industry and second in tourism exploration, have compromised the natural healthy balance.

This paper could be a contribution to a scientific support for political decisions on the coastal zone management (namely in these studied areas).

The paper provides and increases the knowledge of the coastal zones’ evolution and occupation – from a multidisciplinary perspective – produced and made available to scientists, local politicians, students and local populations.

The paper provides a truly interdisciplinary approach, which allows a better understanding of the evolution of these two systems, discussing the causes and consequences of human activities in both coastal areas.