Amount Of Sediment Transport Research Articles

Calculation Analysis of Erosion Rates and Sedimentation Transport in the Liliba Watershed

Erosion is the loss or erosion of land or parts of land from a place by water or wind. Erosion causes the loss of fertile soil layers that are good for plant growth and reduces the soil's ability to absorb and retain water. The Liliba watershed area in Kupang City includes Maulafa District, Oebobo District, Kelapa Lima District. The Liliba River Watershed (DAS) is part of the development of the Noelmina River area which flows into Oesapa Beach. The Liliba watershed has an area of 4,534 hectares with a main river length of 20,176.22 m. Using the USLE Method and SDR Transport Analysis, it was found that the erosion that occurred was 3.72 tonnes per year and the amount of sediment transport that occurred was 2.73 tonnes per year.

STUDY OF WAVE DOMINANT DIRECTIONS ON SEDIMENT TRANSPORT IN THE ESTUARY OF KAPUAS RIVER, PONTIANAK, WEST KALIMANTAN

The Kapuas River is a very important water transportation route in West Kalimantan, crossing 5 districts and 1 city. The problem that occurs in the shipping lane on the Kapuas River is the accumulation of severe sediment at the mouth of the estuary. This becomes an obstacle for ships with large loads to sail, for this reason, this research was carried out. The purpose of this study was to determine the dominant direction of waves and sediment transport. This study was calculated using the CERC (Coastal Engineering Research Centre) method and using secondary data. It was found that the dominant wave direction came from the North (N) direction with an incidence percentage of 22.496%. Percentage of occurrence from the Northwest (NW) direction is 12.145%, from the West (W) direction is 6.253%, and from the Southwest direction (SW) is 11.724%. While the amount of sediment transport from the Northwest is -393062.1306 m3/year with the characteristics of the sediment being clay, from the West it is -250.1672 m3/year with the sediment characteristics being silty clay and from the Southwest, it is 579090.2782 m3/year with sediment characteristics of silty clay. The results of the sediment calculation have negative results which indicate that there is no sediment transport from the Northwest and West, but the sediment is deposited. For this reason, it is necessary to carry out appropriate handling of these problems to reduce sediment build-up in the study area.

Analysis of Changes in Land Use/Land Cover and Hydrological Processes Caused by Earthquakes in the Atsuma River Basin in Japan

The 2018 Hokkaido Eastern Iburi earthquake and its landslides threaten the safety and stability of the Atsuma River basin. This study investigates land use and land cover (LULC) change by analyzing the 2015 and 2020 LULC maps of the basin, and its impact on runoff and sediment transport in the basin by using the soil and water assessment tool (SWAT) model to accurately simulate the runoff and sediment transport process. This study finds that the earthquake and landslide transformed nearly 10% of the forest into bare land in the basin. The simulation results showed that the runoff, which was simulated based on the 2020 LULC data, was slightly higher than that based on the 2015 LULC data, and the sediment transport after the earthquake is significantly higher than before. The rate of sediment transportation after the earthquake, adjusted according to the runoff, was about 3.42 times more than before. This shows that as the forest land decreased, the bare land increased. Conversely, the runoff increased slightly, whereas the sediment transport rate increased significantly in the Atsuma River basin after the earthquake. In future, active governance activities performed by humans can reduce the amount of sediment transport in the basin.

Comparisons of Numerical Models on Formation of Sediment Deposition Induced by Tsunami Run-Up

Tsunami sediments provide direct evidence of tsunami arrival histories for tsunami risk assessments. Therefore, it is important to understand the formation process of tsunami sediment for tsunami risk assessment. Numerical simulations can be used to better understand the formation process. However, as the formation of tsunami sediments is affected by various conditions, such as the tsunami hydraulic conditions, topographic conditions, and sediment conditions, many problems remain in such simulations when attempting to accurately reproduce the tsunami sediment formation process. To solve these problems, various numerical models and methods have been proposed, but there have been few comparative studies among such models. In this study, inter-model comparisons of tsunami sediment transport models were performed to improve the reproducibility of tsunami sediment features in models. To verify the reproducibility of the simulations, the simulation results were compared with the results of sediment transport hydraulic experiments using a tsunami run-up to land. Two types of experiments were conducted: a sloping plane with and without coverage by silica sand (fixed and movable beds, respectively). The simulation results confirm that there are conditions and parameters affecting not only the amount of sediment transport, but also the distribution. In particular, the treatment of the sediment coverage ratio in a calculation grid, roughness coefficient, and bedload transport rate formula on the fixed bed within the sediment transport model are considered important.

Analisa Angkutan Sedimen Pada Hulu Bendung Aepodu Kabupaten Konawe Selatan

Research on Aepodu Weir Sediment Transport Analysis in South Konawe District, based on observations in the field, Aepodu Weir hasa sediment buildup that has now exceeded the height of the weirlight house. The purpose of the study was to analyze the magnitudeof Aepodu river flow and to analyze the amount of sedimenttransport that occurred in the Aepodu dam. The method used todetermine the amount of bed load transport uses stchoklitscht, whilefor transporting suspended load using forcheimer.The results of the analysis of the average flow of the Aepodu riverwere 3,604 m3/ second. Sediment transport that occurs in Aepoduweir is Bedload transport (Qb) of 291625.771 tons / year, andsuspended load transport (Qs) of 16972,423 tons / year, so that thetotal sediment transport (QT) is 308598,194 tons / year.

Angkutan Sedimen Menggunakan Metode Yang Pada Sungai Sombe, Palu, Sulawesi Tengah

The sedimentation process that occurs in in Sombe River is a phenomenon of sediment grainsor particles entrained from the riverbank avalanche. The problem is exacerbated when there is moderate to high intensity rainfall, causing sediment material transported by a flood. The purpose of this study is to identify and estimate the amount of sediment transport in Sombe River. In this research, direct measurements were carried out by taking sediment samples from the Sombe River, furthermore it is also used secondary data such as rainfall data and data characteristics of the watershed. The results of the analysis using the Yang method show that the average value of sediment transport in the Sombe River with a return period of 1 year, 2 years, 5 years and 10 years is 5.7x106 - 7.5x106 tons / year.

Research of Impacts of the 2018 Hokkaido Eastern Iburi Earthquake on Sediment Transport in the Atsuma River Basin Using the SWAT Model

Landslides, debris flows, and other secondary disasters caused by earthquakes threaten the safety and stability of river basins. Earthquakes occur frequently in Japan. Therefore, it is necessary to study the impact of earthquakes on sediment transport in river basins. In this study, considering the influence of reservoirs, the Soil and Water Assessment Tool-calibration and uncertainty program (SWAT-CUP) was employed to analyze the runoff parameter sensitivity and to optimize the parameters. We manually corrected the sediment transport parameters after earthquake, using the Soil and Water Assessment Tool (SWAT) model to assess the process of runoff and sediment transport in the Atsuma River basin before and after the 2018 Hokkaido Eastern Iburi Earthquake. The applicability of the SWAT model to runoff simulation in the Atsuma River basin and the changes of sediment transport process after the earthquake were studied. The research results show that the SWAT model can accurately simulate the runoff process in the Atsuma River basin, the Nash–Sutcliffe efficiency coefficient (NSE) is 0.61 in the calibration period, and is 0.74 in the verification period. The sediment transport increased greatly after the earthquake and it is roughly estimated that the amount of sediment transport per unit rainfall increased from 3.5 tons/mm/year before the earthquake to 6.2 tons/mm/year after the earthquake.

Study of Sediment Transport in Krueng Meureubo River of Padang Mancang Village Kaway XVI Sub District Aceh Barat District

This research was conducted to see the rate of sediment transport in the Krueng Meureubo watershed in Padang Mancang Village, Kaway XVI Subdistrict, West Aceh Regency, where in this village floods often occur due to overflowing of the river, which is predicted to occur due to river silting. The ability of the river to accommodate the flow at the time of flood discharge decreases due to siltation caused by sedimentation of sediment grains originating from erosion of land in the watershed area. Soil erosion is caused by erosion of soil layers due to rain that occurs on land that is prone to erosion, such as open land, forests that have been damaged due to illegal logging and areas whose land functions are transferred. Method used to analyze the sediment transport rate in the Krueng Seunagan watershed is Yang’s method, where the data to be analyzed is primary data in the form of direct measurement results in the field such as river cross-section data, flow velocity and bedload sampling using a sediment trap and suspended load in the river. the amount of sediment transport that occurred along the Meurebo River in Padang Mancang Village was 52.7634168 tons / year.

Analysis of Sediment Transport on the Upstream Code River, Indonesia

Purpose: The Code River is one of the pathways from debris flows of Mount Merapi that crosses the centre of Yogyakarta City, Indonesia. Along the Code River, there are densely populated areas, mainly when the river flows through the centre of Yogyakarta City. Mount Merapi is one of the most active volcanos in Indonesia, also in the world. Based on the data, the volcano usually erupts in 3-year periods for a small scale and nine years for a large scale. Its eruptions produce a considerable material. The eruption material from Mount Merapi carried by the debris flows affected the sedimentation process in rivers that originated in the volcano, particularly the Code River. This research was conducted to find out the amount of sediment transport and its impact on the upstream area of the Code River. Methodology: Methods used in the determination of sediment transport at Code River are Frijlink, Meyer Petter Muller, and Einstein method. Results: Based on the results, it shows that according to the Frijlink method, the sediment transport occurred is 19.79 – 85.43 m3/day and the sediment transport of MPM method is 15.06 - 77.23 m3/day, whereas the sediment transport of Einstein's method is 8.89 – 70.36 m3/day. The results also showed that the calculation of sediment transport using the three methods, a phenomenon of erosion took place at a location between observation points 1 and 2, and a phenomenon of sedimentation occurred at a location between observation points 2 and 3.

Soil erosion and sediment interception by check dams in a watershed for an extreme rainstorm on the Loess Plateau, China

The magnitude of soil erosion and sediment load reduction efficiency of check dams under extreme rainstorms is a long-standing concern. The current paper aims to use check dams to deduce the amount of soil erosion under extreme rainstorms in a watershed and to identify the difference in sediment interception efficiency of different types of check dams. Based on the sediment deposition at 12 check dams with 100% sediment interception efficiency and sub-catchment clustering by taking 12 dam-controlled catchments as clustering criteria, the amount of soil erosion resulting from an extreme rainstorm event on July 26, 2017 (named “7·26” extreme rainstorm) was estimated in the Chabagou watershed in the hill and gully region of the Loess Plateau. The differences in the sediment interception efficiency among the check dams in the watershed were analyzed according to field observations at 17 check dams. The results show that the average erosion intensity under the “7–26” extreme rainstorm was approximately 2.03 × 104 t/km2, which was 5 times that in the second largest erosive rainfall in 2017 (4.15 × 103 t/km2) and 11–384 times that for storms in 2018 (0.53 × 102 t/km2 - 1.81 × 103 t/km2). Under the “7–26” extreme rainstorm, the amount of soil erosion in the Chabagou watershed above the Caoping hydrological station was 4.20 × 106 t. The sediment interception efficiency of the check dams with drainage canals (including the destroyed check dams) and with drainage culverts was 6.48 and 39.49%, respectively. The total actual sediment amount trapped by the check dams was 1.11 × 106 t, accounting for 26.36% of the total amount of soil erosion. In contrast, 3.09 × 106 t of sediment were input to the downstream channel, and the sediment deposition in the channel was 2.23 × 106 t, accounting for 53.15% of the total amount of soil erosion. The amount of sediment transport at the hydrological station was 8.60 × 105 t. The Sediment Delivery Ratio (SDR) under the “7·26” extreme rainstorm was 0.21. The results indicated that the amount of soil erosion was huge, and the sediment interception efficiency of the check dams was greatly reduced under extreme rainstorms. It is necessary to strengthen the management and construction technology standards of check dams to improve the sediment interception efficiency and flood safety in the watershed.

Shore Line Mathematical Modelling and Integrated Groundwater Potentiality Study in the Northern Coast Mediterranean Sea, Egypt

The purpose of this research is to determine surface and subsurface features in the proposed sites. Meanwhile accessibility and availability of water resources. It will have carried out a comprehensive investigations related to topography, geology, hydrology and geophysics. Water samples were collected from the study area and its surroundings to be subjected to different analysis procedures for quality and quantity. The results of the hydrologic analysis showed that all rainfall amounts are infiltrated to the soil and there is no runoff flood water to affect the study area. Consequently, it's concluded that the flood has no harm effect on any of the study area buildings. Based on the geophysical and hydrogeological results, it is strongly recommended drilling three productive wells to a depth of ±50 m at the location of Vertical Electrical Sounding VESes 5 and 7 to produce water from the coral reefs limestone layer where its high fracture density and lower salinity. For future sustainable development plans, it is also possible to drill any number of productive wells in the southern part of the area to avoid the higher degree of sea water intrusion. In this case, the distance between wells must be not less than 120 m. It is conducting a numerical simulation to the coast of the study area in order to inspect the effects of implementing these structures. For that reason, a topographical and a bathymetrical survey were carried to the area in order to simulate the area numerically. The shoreline stabilization was simulated using 20 different orientations to the intake and outlet structures. Based on the mathematical modeling results, it was noticed that the shoreline is naturally stable as it is a smooth East-West shoreline with no undulations and the amount of sediment transport is trivial.

Three-dimensional modelling of sediment transport under tidal bores in the Qiantang estuary, China

ABSTRACTIn this study, a three-dimensional model is developed to investigate sediment transport under tidal bores in the Qiantang estuary. The sediment transport is modelled by the advection and diffusion equation, and the exchange of sediment between the riverbed and the flow is determined by a net flux. A new formula of sediment carrying capacity based on recent field data is used and the settling velocity is resolved with an empirical formula accounting for the flocculation of fine sediment. Skill assessment is employed to show the model performance and relatively high predictive skills are demonstrated. The significant rise of sediment concentration under tidal bores is accurately reproduced. Sediment concentration with the arrival of tidal bores increases more than 10 times, and the depth-varying characteristic of suspended sediment is captured. It is concluded that the amount of sediment transport under tidal bores amplifies an order of magnitude, and the reverse sediment transport pattern is documented.

Kajian Angkutan Sedimen Di Sungai Pabelan, Kabupaten Magelang, Jawa Tengah

Pabelan River is one of the rivers in the western slopes of mount Merapi located in Magelang Regency, Central Java province. Pabelan River has watersheds ± 84,70 km 2 with the main river length ± 28,40 km 2 . The purpose of this research was to estimate the amount of sediment transport that occurred at the point of view in the Pabelan River and to know estimate of sediment balance that occurred at the point of view in the Pabelan River. This research was conducted to find out the sediment balance in the Pabelan River whether going on degradation , aggradation , or experience the equilibrium transport. Calculation of sediment balances based on the volume of sediment transport entering at the location selected. Based on the results of sediment transport analysis using MPM, EINSTEIN, DU BOYS and ROTTNER formula, the largest sediment transport volume occurred in PA-C 5 = 4850,592 m 3 /m/flood, 305,8398 m 3 /m/flood, 20321,979 m 3 /m/flood and 80274,221 m 3 /m/flood, while the result of calculation based on formula FRIJLINK largest sediment transport volume occurred at PA-C 3 = 3654,817 m 3 /m/flood. To obtain the result of equilibrium sediment that occurred in the river of research is by using the five formula with the condition of the river that occurred aggradation and degradation with the biggest condition is the result of calculation with the formula ROTTNER for aggradation occurs in PA-C X Prumpung amount of 47272,806 m 3 /m/s with increase river bed amount of 13,504 m and degradation occurred at PA-C 5 -47468,692 m 3 /m/s with decrease at river bed -23,698 m.

Modeling and Observations of Sand Ripple Formation and Evolution During TREX13

Ripples on the seafloor affect acoustic scattering and transmission loss, wave attenuation, and the amount of sediment transported in shallow water. Historically, seafloor roughness (a function of ripples, bedforms, sediment type, and size) is assumed to be spatially homogeneous and temporally static in hydrodynamic and acoustic models despite the often dynamic nature of the seafloor in the nearshore region. We present a spectral ripple model, Navy Seafloor Evolution Archetype (NSEA), which simulates the variations in seafloor roughness given measured or predicted wave conditions in sandy environments. NSEA simulates sand ripple formation and evolution based on bottom velocities either measured or predicted by a wave model. The time dependency is a function of equilibrium ripple geometries and the amount of sediment transport needed to reach an equilibrium state, which is dependent on the relict ripples. Spectral decay due to bioturbation is incorporated as a diffusive process. NSEA was validated with time series observations obtained in water depths of 7.5 and 20 m from April 20, 2013 to May 23, 2013 during the 2013 Target and Reverberation Experiment (TREX13) offshore of Panama City, FL, USA. The model predicted spectral ripple wavelengths that were in good agreement with observed spectral ripple wavelengths obtained using a fixed platform, high-frequency (2.25 MHz) sector scanning sonar. Likewise, the variations in the predicted normalized ripple heights and orientations were similar to the normalized spectral decay and orientations estimated from the sector scanning sonar imagery.

Effect of vortex formation on sediment transport at dual pipe intakes

Vortex formation and subsequent sediment transport into the intake due to sea water withdrawal is one of the problems in coastal engineering. The effect of vortex formation on rate of sediment transport at coastal dual pipe intakes was investigated using a scaled physical model. Experiments were performed on dual pipe intakes at three common intake withdrawal directions (vertical, horizontal and with angle of 45°). In each experiment, the class of vortex with respect to its strength was determined. Particle tracking velocimetry (PTV) was employed to measure tangential velocity of vortices. Results indicated that the rate of sediment transport was considerably affected by the strength of formed vortices. The rate of transported sediment was increased by increasing the strength of formed vortex. Moreover, amount of sediment transport was affected by angle of pipe intakes. It could be concluded that the minimum and maximum rates of sediment transport occur for inclined and horizontal intakes, respectively.

The Analysis of Sediment Transport Using Yang Method, Engelund-Hansen Method, and Bagnold Method in Bah Bolon River, Simalungun Regency of North Sumatera

The development of the construction that changes land use has resulted the decreasing of infiltration and erosion and the increasing of the sedimentation. So, the floated sediment in the river of Bah Bolon can interfere the performance of turbines of Microhydro Power Plant (MHP). The planning of sediment harvesting media requires data of total amount of sediment transport that occurs in the River of Bah Bolon. So the "The Analysis of Sediment Transport in River of Bah Bolon" needs to be done. Based on secondary data, there are two samples in this study. Sediment transport analysis using three methods, namely Yang Method, Method of Engelund and Hansen, and Bagnold Method. The analyzes show the results of the amount of sediment transport. In the first sample, the results of that three method analysis respectively are 1041.23 tons/year; 12.60 tons/year, and 241.63 tons/year. In the second sample, the results of the three method analysis respectively are 1210.36 tons/year; 11.49 tons/year; and 241.63 tons/year. The results were compared with the results of the calculation of Intan (2015) to conclude what method that is best applied in Bah Bolon River. By ratio analysis, Yang Method is the best method compared to other methods that analiyze the total sediment transport in the Bah Bolon River. The author is not recommend using Bagnold Method or Engelund and Hansen Method to calculate the amount of sediment transport in Bah Bolon river.

BED VARIATION ANALYSIS IN THE CHIKUGO RIVER ESTUARY BY THE FLOOD FLOWS

A series of fisherie issues in the Ariake sea has been believed to be caused by a lack of sand supply from the Chikugo river on the basis of few investigations of characteristics and amount of sediment transport in the the Chikugo river estuary. The core sampling and super-sonic echo sounder indicates that the vertical structure of mid stream of the Chikugo river estuary is consists of complex alternate layer and the rate of water content is much different to each layer. To make the rate of sand transport in the Chikugo river estuary clear, the authors applied unsteady quasi-three dimensional flood flow and river bed variation analysis using observed temporal changes in water surface profiles of flood. In the analysis, the bed layer which the rate of water content upper than 70% is calculated 2009by the experimental equation of erosion speed of the cohesive material. The results of analysis indicates that the rate of sand supply is strongly affected by the tidal level change of the Ariake sea.

CHARACTERISTICS OF TURBULENT BOUNDARY LAYER OVER A ROUGH BED UNDER CNOIDAL WAVES MOTION

Ocean waves in reality often have a strong non-linear shape when propagating to shallow water, and the gap from the sinusoidal wave become remarkable. Therefore, it is generally believed that wave boundary layers, bottom shear stress and sediment transport behaviors actualizing the effect of non-linearity are different from sinusoidal wave. However, the example of research treating such turbulent boundary layer and sediment transport characteristic is very few. Therefore, the accuracy of bottom shear stress and amount of sediment transport used to evaluate the beach morphological change obtained from the wave motion model of sinusoidal is necessary to be clarified by that of non-linear. In this present study, turbulent boundary layer characteristics for asymmetric or non -linear waves according to the non-linearity effect is examined through both experimental and BSL turbulence model. Moreover, a new calculation method of botto m shear stress based on incorporating acceleration and velocity terms is used to examine both the experimental and BSL model results of bottom shear stress.

SEASONAL BEACH PROCESS AROUND ARTIFICIAL REEF AT IDA BEACH IN SHICHIRI-MIHAMA COAST

This paper is intended to estimates easonal beach process and wave deformations around artificial reefs at the Ida beach in the Shichiri-Mihamac oast in Mie Prefecture. It is clear that almost regions occurredbeach erosion, especially Udono port region located on the left bank of the Kumano river, as the coastal line faced to sea, the beach protectionw orks weres truckb y strong storms. In order to prevente rosion and make a stableb each, the application of beach nourishment behind artificial reefs was examined by Mie Prefectural Government. A series of surveys and studies on sand drift and wave conditions were conducted in order to examine the sand drift process, the possibility of applying beach nourishment and its executive way at the Ida beach. There are the formation of berm and tombolo topography behind artificial reefs. Resultsw ere estimated on the sediment volume and the predominant direction of sand transport and the correlation between longshores and transport volume and wave condition. On the basis of these results, the amount of sediment transport in longshored irection were estimated thirty thousands cubic meters a period of typhoon season at the boundary.

The effects of marine gravel extraction on the macrobenthos: Results 2 years post-dredging

An offshore experimental dredging study was initiated off North Norfolk (UK) in 1992 to investigate the impacts of marine gravel extraction on the macrofauna. A dredged ‘treatment’ and a non-dredged ‘reference’ site were selected to evaluate the initial impacts and subsequent processes of recolonization. A survey of the benthos was conducted prior to the removal of 50 000 t of marine aggregate from the treatment site. Thereafter annual monitoring surveys were conducted commencing immediately after the dredging episode. Results indicated that whilst the dominant species recolonized quickly following dredging many rarer species did not. Evidence from sidescan sonar records and underwater cameras indicated a considerable amount of sediment transport during the first two winters following dredging and the once well-defined dredge tracks have now become infilled with sand and gravel. The substantially reduced biomass at the treatment site some 24 months after dredging is thought to be due to a local increase in sediment disturbance caused by tide and wave action over the winter period. Finally, the biological findings of this study are discussed in relation to their wider environmental significance.