Sediment Transport In Rivers Research Articles

Sediment sources and delivery of Norwegian mountain rivers in a changing climate

AbstractThe projected climate change for Norway through the 21st century predicts that the temperature will increase significantly. Events with heavy rainfall will be more intense and occur more frequently. Rain floods will increase in magnitude and also occur more frequently. Extreme flooding and heavy rain will significantly impact the sediment dynamics in rivers. In the mountain areas, floods are often associated with erosion, transport and deposition of coarse sediment along the streams. These processes are related to bed load transport and pose a hazard in addition to the elevated water discharge and have to be included in management plans for river basins. This article studies the bed load delivery from sources that contribute the most to the sediment budget in the Gudbrandsdalslågen river basin during the large magnitude floods in 2011 and 2013. More than 100 debris slides and debris flow were triggered in the tributary river Veikleåi by the heavy rain and snowmelt during these floods. The volume of the contribution from debris flows and erosion and deposition of the river bed was determined by subtracting digital elevation models acquired during repeated airborne LIDAR surveys. In the river Dørja the supply of sediment from a number of debris flows caused extensive aggradation and channel changes. In their new position, lateral erosion by these channels triggered slides on the adjacent slopes. The contributing volumes of debris flows, lateral erosion, and river bed erosion and deposition were determined from the LIDAR surveys. Relations obtained from studies of sediment transport in modern glacier rivers were used to obtain estimates of the ratio of bed load versus suspended load derived from the Pleistocene moraine deposits. Several monitoring stations using conventional methods for measuring bed load and suspended load recorded very large volumes of sediment delivery during both of the extreme floods. The results of the study may be used to identify necessary locations for check‐dams and erosion protection works in order to adapt to climate change.

A multi-decadal analysis of river discharge and suspended sediment load in three Texas coastal rivers in relation to hurricanes, seasonal rainfall, and ENSO

Coastal river discharge and sediment load exert major influence on the sustainability of coastal systems. Controlled by various hydroclimatic/hydrometeorological agents, they exhibit distinct trend/variability at different time scales. Coastal Texas, while being a major target for tropical cyclones over the past 6 decades, has been experiencing drought and flood cycles associated with ENSO in the long term. However, it is still unclear the temporal variability of river discharge and the associated sediment delivery over this area at different time scales, and the controlling factors behind it. In this study, a 58-years (1960–2017) dataset is compiled to analyze the influence of ENSO, seasonal rainfall distribution and hurricanes event on the river discharge and suspended sediment load of three Texas coastal rivers-the San Bernard River, the Brazos River, and the Trinity River, at annual, seasonal and event scales, respectively. In the short-term, all three rivers attained the highest average daily discharge and sediment load during Hurricane Harvey. On a seasonal scale, the precipitation regime exerts more influence on the Texas watersheds than tropical storms and hurricanes. Over a multi-decadal scale, amplified rainstorms during the El Niño phases likely play an important role in the overall discharge and sediment transport in large rivers along the northern Gulf coast. Overall, it is reasonable to conclude that the magnitude of hurricane impacts on the overall discharge and suspended sediment load is regulated by the duration and intensity of the rainfall, as well as the coupled drought-flood cycle in relation to the intensity of ENSO.

Modeling of 1D sediment transport in the langat river using quasi-unsteady HEC-RAS

The primary goal of this research was to investigate the sediment transport characteristics of the Langat River. The Langat River is situated in the state of Selangor, Malaysia, and is prone to flooding on a regular basis. The River Analysis System tool from the Hydraulic Engineering Center (HEC-RAS) was used to determine the sediment transport capacity of the river. The sediment transport and hydraulic models were created using elevation and cross-sectional data in HEC-RAS. The sediment transport model employed several approaches to calculate sediment transport capacity. HEC-RAS contains some useful built-in functions which were used in this study to visualize the sediment transport, calibration and calculation of Manning’s roughness coefficients, and forecast changes in bed elevation. The investigation reveals that urban development has resulted in a large rise in riverbed depth, implying that is no difference in flooding pattern in the short period of time. This paper focuses only on bed load sediment. The results of three years of stream flow show that some areas have experienced silt transport and river deposition. The river had changed slightly after utilizing the Laursen-Copeland method in HEC-RAS. The simulation outcome shows the segment that experienced sediment transport at River Stations RS 12926 from Lui, RS 9362 from Langat upper reach, and RS 3730 from Langat Lower Reach are experiencing sediment deposition activities.

A reproducing kernel Hilbert space method for nonlinear partial differential equations: applications to physical equations

The partial differential equations (PDEs) describe several phenomena in wide fields of engineering and physics. The purpose of this paper is to employ the reproducing kernel Hilbert space method (RKHSM) in obtaining effective numerical solutions to nonlinear PDEs, which are arising in acoustic problems for a fluid flow. In this paper, the RKHSM is used to construct numerical solutions for PDEs which are found in physical problems such as sediment waves in plasma, sediment transport in rivers, shock waves, electric signals’ transmission along a cable, acoustic problems for a fluid flow, vibrating membrane, and vibrating string. The RKHSM systematically produces analytic and approximate solutions in the form of series. The convergence analysis and error estimations are discussed to prove the applicability theoretically. Three applications are tested to show the performance and efficiency of the used method. Computational results indicated a good agreement between the exact and numerical solutions.

Channel bar development, braiding and bankline migration of the Brahmaputra-Jamuna river, Bangladesh through RS and GIS techniques

ABSTRACT Erosion of banks and channel migrations are usually common phenomenon and recurring geo-hazardous problem in the Brahmaputra-Jamuna river system of Bangladesh. The present study intensively analysed multi-temporal Landsat satellite imageries (Landsat MSS, Landsat TM, Landsat ETM+, Landsat OLI TIRS), historical documents (Hunter maps), and literature information employing Remote Sensing and Geographic Information System techniques, and estimation of braiding and sinuosity indices especially emphasizing channel bar development, braiding, and bank-line migration of the river. The computed braiding indices of the river were 1.5, 10.3, 13.4, 11.0, 10.6 and 14.6 for the year of 1853–1857, 1977, 1989, 2000, 2014 and 2018, respectively (overall deciphering increasing trend). Similar to the braiding indices, the sinuosity indices (2.58, 7.02, 9.92, 8.31, 7.42 and 11.25 for the same selected years) of the river have also been changed over time. During 1853–1857 to 2018, 766.7 and 1624.2 km2 of lands extensively eroded on the east and west bank, respectively at a rate of 4.8 and 10.1 km2 yr−1. However, from 1977 to 2018, the erosion rates were 14.4 and 12.5 km2 yr−1, respectively. High discharges, sediment transport associated with random bars formation related braiding expansion, and weak bank materials are presumably the governing factors for causing such simultaneous severe bank erosion and remarkable bank-line migration phenomenon. Although, from 1853–1857 to 1977 the erosion of the river followed the river flow direction. It is expected that the outcomes of this research can contribute further research on morphodynamic characteristics of the braided river for better understanding the river characteristics, the river hydromorphology, water and sediment transport, its bank erosion, and formulating protective measurement plan for their sustainable current flow path maintenance.

Linking levee-building processes with channel avulsion: geomorphic analysis for assessing avulsion frequency and channel reoccupation

Abstract. A natural levee is a typical wedge-shaped deposit adjacent to a river channel. Given its location and distinctive features, the levee can serve as a key to revealing depositional processes of the coupled channel to floodplain system preserved in the rock record. Levee–floodplain topographic evolution is also closely linked to river avulsion processes which can cause catastrophic floods. Nonetheless, the levee geometry and its aggradation pattern on the floodplain have not been fully incorporated in the study of avulsion. Here, we present a levee-building model using advection settling of suspended sediment to reproduce the evolution of a fluvial levee over floods and to examine the effects of boundary conditions on levee geometry and the grain-size trend of the levee deposit. We further investigate river avulsion frequencies and potential channel reoccupation associated with the grain-size distribution of overbank sediment flux and the overflow velocity into the floodplain, both of which can control the levee geometry, especially the aggradation rate at the levee crest. In the modeling results, the levee develops (1) a concave-up profile, (2) an exponential decrease in grain size of the deposit away from the main channel, and (3) a relatively steeper shape for coarser sediment supply and vice versa. The subsequent scaling analysis supports that the input grain size to the floodplain and levee profile slope are positively correlated with the avulsion frequency, whereas the overflow velocity is inversely proportional to the avulsion frequency. In connection with the avulsion styles and levee geometry, we suggest that relatively steeper levee slopes tend to promote more reoccupations of preexisting floodplain channels as protecting abandoned channels from topographic healing, but relatively gentler levees are likely to create a new avulsion channel as their remnant channels are more vulnerable to the removal of topographic memory. The insights drawn from the current modeling work may thus have potential implications for reconstructing paleoenvironments in regard to river sediment transport and flood dynamics via levee deposits. Based on the roles of natural levees on the avulsion frequency and channel reoccupation, the flood hazards triggered by river avulsions as well as the alluvial architecture in sedimentary records can be better assessed.

Contributions of different sources to sediment transport in the Middle Yangtze River under intensive channel degradation

Sediment transport in alluvial rivers is critical to reshape channel morphology and to the global geochemical cycle. This study reports a detailed investigation into the contributions of different sources to sediment transport in the Middle Yangtze River (MYR). It is found that: (i) after the operation of the Three Gorges Project (TGP), the dominant sediment source in the MYR changed from the upstream input to the fluvial erosion and tributary input, with the upstream input providing 38% of the outlet sediment amount in the MYR and the fluvial erosion and tributary input providing around 39% and 23%, respectively; (ii) river bed erosion contributed to 21% of the transported sediment after the TGP, whereas bank erosion contributed to around 18%, which was estimated to be 2 times larger if bank protection works were not constructed after the TGP; (iii) in terms of the sediment transport processes of different fractions after the TGP, the fraction of fine sediment (diameter d ≤ 0.31 mm) in the MYR mainly came from the upstream and tributary input, and the fraction of medium sediment (0.31 mm < d ≤ 0.125 mm) almost equally came from each source, whereas the fraction of coarse sediment (d > 0.125 mm) was primarily eroded from the bed and banks. Besides, the MYR was transformed from a transport-limited river system into a supply-limited one after the TGP operation, with the total amount of sediment supply accounting for 21% of its transport capacity under current flow and boundary conditions. The development of bed armoring in the main stream and the construction of various river regulation works, would result in a further decrease in the sediment supply rate of the MYR in the future.

Flow Strength and Bedload Sediment Travel Distance in Gravel Bed Rivers

AbstractThe quantification of bedload sediment transport in rivers is possible from statistics of individual particle displacements. However, there is a lack of empirical basis for a universal relation between particle displacement distance and hydraulic drivers. Previous work suggests that a simple linear relation exists between the energy of a flood and the mean travel distance of bedload particles. Such a relation would be advantageous, but a consistent model able to collapse the data from different rivers has not been developed. Here, we develop a predictive relation from a unique data set collected in three watersheds from a single region but contrasting hydrologic regimes due to urbanization and storm water management. Additional data from two rivers from outside the region are used to validate the model. We show that the mean of an exponential distribution of surface particle travel displacements can be reliably predicted from either the cumulative discharge or stream power exceeding the mobilization threshold, which is calibrated using field data. The strength of the relation decreases after large flood events that appear to cause tracer burial due to vertical mixing. This result indicates that the relation is most applicable for the entrainment phase of transport in which tracers are dispersing over the bed surface. Tracer movements become more challenging to predict over a long series of events due to burial and eventual tracer slowdown, but the relation remains valid for the particles located on the bed surface, making it suitable for analyzing the impact of climate and landscape changes over time.

Recent variation in channel erosion efficiency of the Lower Yellow river with different channel patterns

• Both temporal and spatial declines existed in the channel erosion efficiency of the Lower Yellow River. • An excessive decrease in sediment transport capacity and a deficit of riverbed supply led to the temporal decline in channel erosion efficiency. • Cross-sectional geometry and bed material composition were the key factors to cause the differences in channel erosion efficiency of different reaches in the LYR. The operation of the Xiaolangdi Reservoir has exerted prominent effects on the processes of sediment transport and channel evolution in the Lower Yellow River (LYR) since 2000. The investigation into the spatio-temporal adjustment characteristics of channel evolution is of significance to the management of the LYR covering different channel-pattern reaches of braided, transitional and meandering. An indicator of channel erosion efficiency was firstly defined as the ratio of annual channel evolution volume to annual incoming water volume in a specified study reach. Furthermore, the values of channel erosion efficiency in different reaches of the LYR were calculated using the measured hydrological data and cross-sectional profiles during the post-dam stage. Calculated results show that the channel erosion efficiency in the LYR was exhibiting a decline tendency at both temporal and spatial scales, with the mean value of the whole reach decreasing from 6.0 (2000–2007) to 2.7 (2008–2020) and that of the braided reach four times higher than the meandering reach. Main factors influencing the channel erosion efficiency were investigated, covering the incoming flow-sediment regime, riverbed composition and cross-sectional geometry. The temporal decreases in these factors, including incoming sediment coefficient, bed material supply and geomorphic coefficient, resulted in the temporal decline in channel erosion efficiency. The discrepancies in channel erosion efficiency of different reaches were mainly ascribable to the variations in cross-sectional geometry and riverbed composition. The geomorphic coefficient in the braided reach decreased from 19.7 to 9.0 m −1/2 , and meanwhile the percentages of fine and medium grain sizes in the riverbed reduced by around 50% from 2000 to 2020, which led to the most dramatic variation in channel erosion efficiency and the different trajectory of channel evolution. In addition, the seldom varied channel slope played a minor role in the temporal variation of channel erosion efficiency, but partly accounted for the spatial reduction along the LYR. This study provides an illustrative example for the response of a large alluvial river with different channel patterns to the varying boundary conditions caused by upstream damming.

Open-source, low-cost, in-situ turbidity sensor for river network monitoring

Fine sediment transport in rivers is important for catchment nutrient fluxes, global biogeochemical cycles, water quality and pollution in riverine, coastal and marine ecosystems. Monitoring of suspended sediment in rivers with current sensors is challenging and expensive and most monitoring setups are restricted to few single site measurements. To better understand the spatial heterogeneity of fine sediment sources and transport in river networks there is a need for new smart water turbidity sensing that is multi-site, accurate and affordable. In this work, we have created such a sensor, which detects scattered light from an LED source using two detectors in a control volume, and can be placed in a river. We compare several replicates of our sensor to different commercial turbidity probes in a mixing tank experiment using two sediment types over a wide range of typical concentrations observed in rivers. Our results show that we can achieve precise and reproducible turbidity measurements in the 0–4000 NTU or 0–16g/L range. Our sensor can also be used directly as a suspended sediment sensor and bypass an unnecessary calibration to Formazin. The developed turbidity sensor is much cheaper than existing options of comparable quality and is especially intended for distributed sensing across river networks.

Influence of invasive crayfish on fine sediment transport, ingress and bed storage in lowland rivers

AbstractHistorically it has been assumed that abiotic forces dominate fluvial sediment dynamics. However, a growing body of work indicates that biological energy can also exert a significant control over sediment dynamics. The role that invasive species may play in altering fine sediment dynamics is particularly pertinent given that any influence may disrupt the natural equilibrium of the ecosystem. Here we investigated the effect of invasive signal crayfish (Pacisfastcus leniusculus) on the transport and storage of fine sediment in a densely populated river compared with a nearby control river without crayfish, over an 18‐week period. We observed clear evidence of diurnal fluctuations in turbidity associated with crayfish presence including periodograms with power peaks at a period of 1 day. Fine sediment fluxes indicated that crayfish contributed on average 18.5% extra to baseflow loads than would be likely under abiotic forcing alone. Temporal variations in suspended sediment concentrations were also observed at the control site but these were different in character and exhibited no clear temporal pattern or consistency as confirmed by periodogram analysis. Crayfish did not have an effect on sediment ingress rates relative to the control site and, at the crayfish site, the reach scale sediment budget was in net equilibrium during the sampling period. Our results provide further evidence that biological energy alters riverine fine sediment dynamics and warrants consideration in sediment dynamic models.

Quantitative relationships between river and channel-belt planform patterns

Abstract Channel planform patterns arise from internal dynamics of sediment transport and fluid flow in rivers and are affected by external controls such as valley confinement. Understanding whether these channel patterns are preserved in the rock record has critical implications for our ability to constrain past environmental conditions. Rivers are preserved as channel belts, which are one of the most ubiquitous and accessible parts of the sedimentary record, yet the relationship between river and channel-belt planform patterns remains unquantified. We analyzed planform patterns of rivers and channel belts from 30 systems globally. Channel patterns were classified using a graph theory-based metric, the Entropic Braided Index (eBI), which quantifies the number of river channels by considering the partitioning of water and sediment discharge. We find that, after normalizing by river size, channel-belt width and wavelength, amplitude, and curvature of the belt edges decrease with increasing river channel number (eBI). Active flow in single-channel rivers occupies as little as 1% of the channel belt, while in multichannel rivers it can occupy &amp;gt;50% of the channel belt. Moreover, we find that channel patterns lie along a continuum of channel numbers. Our findings have implications for studies on river and floodplain interaction, storage timescales of floodplain sediment, and paleoenvironmental reconstruction.

Insights into Flood Wave Propagation in Natural Streams as Captured with Acoustic Profilers at an Index-Velocity Gaging Station

Recent advances in instruments are transforming our capabilities to better understand, monitor, and model river systems. The present paper illustrates such capabilities by providing new insights into unsteady flows captured with a Horizontal Acoustic Current Profiler (HADCP) integrated at an operational index-velocity gaging station. The illustrations demonstrate that the high-resolution stage and velocity measurements directly acquired during flood wave propagation reveal the intricate interplay among flow variables that are essential for better supporting judicious decision making for river management, flooding, sediment transport, and stream ecology. The paper confirms that the index-velocity method better captures the unsteady flow dynamics in comparison with the stage-discharge monitoring approach. At a time when the intensity and frequency of floods is continuously increasing, a better understanding of the critical features of flood waves during extreme events and the possibility of capturing more accurately their dynamics in real time is of special socio-economic significance.

Assessment of Hydrological Processes in an Ungauged Catchment in Eritrea

This study investigates the surface processes taking place in an ungauged catchment in the Foro region in Eritrea (East Africa). We focus on estimating river discharge, sediment transport, and surface runoff to characterize hydrological fluxes in the area and provide a preliminary quantification of sediment transport and erosion. In this context, an overarching objective of the research is the study of the catchment associated with the Foro Dam. The latter comprises a silted reservoir formerly employed for agricultural water supply. The main traits associated with the system behavior across the watershed are assessed for a variety of combinations of the parameters governing the hydrological model selected. A detailed sensitivity analysis is performed to quantify the effects of the hydrological parameters on the estimated results. Numerical analyses are then performed to obtain an appraisal of expected water and sediment fluxes. Outputs of interest are largely dominated by the curve number parameter.

Median bed-material sediment particle size across rivers in the contiguous US

Abstract. Bed-material sediment particle size data, particularly the median sediment particle size (D50), are critical for understanding and modeling riverine sediment transport. However, sediment particle size observations are primarily available at individual sites. Large-scale modeling and assessment of riverine sediment transport are limited by the lack of continuous regional maps of bed-material sediment particle size. We hence present a map of D50 over the contiguous US in a vector format that corresponds to approximately 2.7 million river segments (i.e., flowlines) in the National Hydrography Dataset Plus (NHDPlus) dataset. We develop the map in four steps: (1) collect and process the observed D50 data from 2577 U.S. Geological Survey stations or U.S. Army Corps of Engineers sampling locations; (2) collocate these data with the NHDPlus flowlines based on their geographic locations, resulting in 1691 flowlines with collocated D50 values; (3) develop a predictive model using the eXtreme Gradient Boosting (XGBoost) machine learning method based on the observed D50 data and the corresponding climate, hydrology, geology, and other attributes retrieved from the NHDPlus dataset; and (4) estimate the D50 values for flowlines without observations using the XGBoost predictive model. We expect this map to be useful for various purposes, such as research in large-scale river sediment transport using model- and data-driven approaches, teaching environmental and earth system sciences, planning and managing floodplain zones, etc. The map is available at https://doi.org/10.5281/zenodo.4921987 (Li et al., 2021a).

Modelling of River Flows, Sediment and Contaminants Transport

Economic development projects in river basins, involving mining, forestry, agriculture and urban developments, invariably impact the aquatic ecosystems of the basin [...]

Quantitatively distinguishing the factors driving sediment flux variations in the Daling River Basin, North China

Understanding the riverine sediment load regime is crucial to sustainably managing fluvial-deltaic ecosystem restoration. However, in studies on global river sediment transport characteristics, small mountainous rivers (SMRs), transporting 45% of the global sediment flux into the sea, have been largely ignored. Furthermore, SMRs have hydrologic characteristics of instantaneous enormous fluxes under extreme climate, but the research on their driving factors affecting sediment transport is insufficient. Partial derivation method and multiple double mass curves were applied to a small mountainous river in North China, the Daling River to study how the three most variable factors—precipitation, vegetation coverage, and reservoirs—have quantitatively controlled sediment flux in the basin and its subregions in the last 50 years. The results of the two methods showed that the 78.55% reduction in sediment flux from 1961–1979 to 1980–2015 was due primarily to restored vegetation coverage (50.42%-61.11%), followed by reservoirs (18.13–44.09%) and precipitation (5.49–22.34%) in the Daling River Basin (DRB) and its subregions. The restored vegetation in the DRB has intercepted a large amount of sediment, reducing the sediment flux transported to the reservoirs. Besides, the Daling River releases enormous amounts of sediment during heavy rainfalls. However, increasing vegetation coverage in recent years has changed the transport characteristics of sediment into temperate changes in runoff and sediment flux under extreme climatic conditions; thus this river provides a useful example of studying the characteristics of sediment transport controlled by nature and human activities against extreme climate conditions. In the DRB, topography, lithology, and vegetation density are the motivators for the differences in sediment flux and its change rates, from upstream to downstream. These findings emphasize the crucial role of vegetation in driving sediment transport from source to sink in temperate SMRs.

Aquatic Insect Bioconstructions Modify Fine‐Sediment Entrainment and Mobility

AbstractThe importance of two‐way interactions between animals and the physical hydraulic and sedimentological environment are increasingly recognized (e.g., zoogeomorphology). Caddisflies (Trichoptera) are a group of aquatic insects known for their bioconstructions, particularly cases built from fine sediment and silk. Caddisfly cases differ in size, shape and density from the incorporated sediment, and case construction may therefore affect the mobility of these sediments in rivers. However, although communities of caddisfly often use substantial quantities of sediment in case construction, the effect of these bioconstructions on sediment transport in rivers is unknown. We use a flume experiment to compare the bed shear stress required to transport (a) empty caddisfly cases and (b) individual sediment particles, following disaggregation from the case. The cases of three species were considered; two that construct different styles of tubular case (Potamophlax latipennis and Sericostoma personatum) and one that builds a domed case (Agapetus fuscipes). P. latipennis and S. personatum cases were easier to entrain than the sediment grains incorporated into them, whilst A. fuscipes cases were not. Despite their low mass, A. fuscipes cases required the most shear stress to transport them because their domed shape impeded rolling. These findings are important to understand how differences in case design between species, reflect different adaptation strategies to the turbulent hydraulic river habitat. Furthermore, the results suggest that un‐attached tubular caddisfly cases may be preferentially transported over other particles on the river bed and thus, where caddisfly occur in high abundance, they may increase fluvial entrainment of sand.

Travertine crystal growth ripples record the hydraulic history of ancient Rome\u2019s Anio Novus aqueduct

Travertine crystal growth ripples are used to reconstruct the early hydraulic history of the Anio Novus aqueduct of ancient Rome. These crystalline morphologies deposited within the aqueduct channel record the hydraulic history of gravity-driven turbulent flow at the time of Roman operation. The wavelength, amplitude, and steepness of these travertine crystal growth ripples indicate that large-scale sustained aqueduct flows scaled directly with the thickness of the aqueous viscous sublayer. Resulting critical shear Reynolds numbers are comparable with those reconstructed from heat/mass transfer crystalline ripples formed in other natural and engineered environments. This includes sediment transport in rivers, lakes, and oceans, chemical precipitation and dissolution in caves, and melting and freezing in ice. Where flow depth and perimeter could be reconstructed from the distribution and stratigraphy of the travertine within the Anio Novus aqueduct, flow velocity and rate have been quantified by deriving roughness-flow relationships that are independent of water temperature. More generally, under conditions of near-constant water temperature and kinematic viscosity within the Anio Novus aqueduct channel, the travertine crystal growth ripple wavelengths increased with decreasing flow velocity, indicating that systematic changes took place in flow rate during travertine deposition. This study establishes that travertine crystal growth ripples such as those preserved in the Anio Novus provide a sensitive record of past hydraulic conditions, which can be similarly reconstructed from travertine deposited in other ancient water conveyance and storage systems around the world.

Effect of input-target datasets on sediment transport modelling in alluvial rivers using artificial neural network

ABSTRACT Numerical simulation of sediment transport in alluvial rivers often becomes untenable due to the absence of requisite data. Over the years, artificial neural network (ANN) models have been successfully employed for tackling such scenarios. However, the effect of input and target datasets on the simulation of sediment transport using ANN has not yet been adequately addressed in the literature so far. To study the effect of input-target dataset on the performance of ANN models, the present study employs seven input-target datasets for the development of several ANN models and assessment of their performance. The limited study carried out reveals that there are multiple ANN models – having different combinations of training algorithms, transfer functions and input/target datasets – that can reliably be employed to estimate bed elevation changes in alluvial rivers.