A System for Measuring Total Sediment Yield from Small Watersheds

This study analyzed the influence of climate change on sediment yield variation, sediment transport and erosion deposition distribution at the watershed scale. The study was based on Gaoping River basin, which is among the largest basins in southern Taiwan. To carry out this analysis, the Physiographic Soil Erosion Deposition (PSED) model was utilized. Model results showed a general increase in soil erosion and deposition volume under the A1B-S climate change scenario. The situation is even worsened with increasing return periods. Total erosion volume and total sediment yield in the watershed were increased by 4–25% and 8–65%, respectively, and deposition volumes increased by 2–23%. The study showed how climate change variability would influence the watershed through increased sediment yields, which might even worsen the impacts of natural disasters. It has further illustrated the importance of incorporating climate change into river management projects.

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Re-suspension of bed sediment in a small stream – results from two flushing experiments

Hydrology and Earth System Sciences ◽

10.5194/hess-18-1043-2014 ◽

2014 ◽

Vol 18 (3) ◽

pp. 1043-1052 ◽

Cited By ~ 25

Author(s):

A. Eder ◽

M. Exner-Kittridge ◽

P. Strauss ◽

G. Blöschl

Keyword(s):

Sediment Load ◽

Free Water ◽

High Temporal Resolution ◽

Sediment Sources ◽

Small Stream ◽

Bed Sediments ◽

Small Watersheds ◽

Wave Celerity ◽

Total Sediment ◽

Stream Bed

Abstract. Streams draining small watersheds often exhibit multiple peaking sedigraphs associated with single peaking hydrographs. The process reasons of the multiple sediment peaks are not fully understood but they may be related to the activation of different sediment sources such as the stream bed itself, where deposited sediments from previous events may be available for resuspension. To understand resuspension of stream bed sediments at the reach scale we artificially flooded the small stream of the HOAL Petzenkirchen catchment in Austria by pumping sediment-free water into the stream. Two short floods were produced and flow, sediment and bromide concentrations were measured at three sites with high temporal resolution. Hydrologically, the two flood events were almost identical. The peak flows decreased from 57 to 7.9 L s−1 and the flow volumes decreased from 17 to 11.3 m2 along the 590 m reach of the stream. However, a considerably smaller sediment load was resuspended and transported during the second flood due to depletion of stream bed sediments. The exception was the middle section of the stream, where more sediment was transported during the second flood event which can be explained by differences between flow velocity and wave celerity and the resulting displacement of sediments within the stream. The results indicate that the first peak of the sedigraphs of natural events in this stream is indeed caused by the resuspension of stream bed sediments, accounting for up to six percent of the total sediment load depending on total flow volume.

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Laboratory studies on bedload transport under unsteady flow conditions

Journal of Hydrology and Hydromechanics ◽

10.1515/johh-2017-0032 ◽

2018 ◽

Vol 66 (1) ◽

pp. 23-31 ◽

Cited By ~ 5

Author(s):

Magdalena M. Mrokowska ◽

Paweł M. Rowiński ◽

Leszek Książek ◽

Andrzej Strużyński ◽

Maciej Wyrębek ◽

...

Keyword(s):

Shear Stress ◽

Sediment Yield ◽

Water Surface ◽

Bedload Transport ◽

Bed Shear Stress ◽

Surface Slope ◽

Stream Power ◽

Transport Dynamics ◽

Water Surface Slope ◽

Total Sediment

Abstract Two sets of triangular hydrographs were generated in a 12-m-long laboratory flume for two sets of initial bed conditions: intact and water-worked gravel bed. Flowrate ranging from 0.0013 m3 s-1 to 0.0456 m3 s-1, water level ranging from 0.02 m to 0.11 m, and cumulative mass of transported sediment ranging from 4.5 kg to 14.2 kg were measured. Then, bedload transport rate, water surface slope, bed shear stress, and stream power were evaluated. The results indicated the impact of initial bed conditions and flow unsteadiness on bedload transport rate and total sediment yield. Difference in ratio between the amount of supplied sediment and total sediment yield for tests with different initial conditions was observed. Bedload rate, bed shear stress, and stream power demonstrated clock-wise hysteretic relation with flowrate. The study revealed practical aspects of experimental design, performance, and data analysis. Water surface slope evaluation based on spatial water depth data was discussed. It was shown that for certain conditions stream power was more adequate for the analysis of sediment transport dynamics than the bed shear stress. The relations between bedload transport dynamics, and flow and sediment parameters obtained by dimensional and multiple regression analysis were presented.

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Re-suspension of bed sediment in a small stream – results from two flushing experiments

Hydrology and Earth System Sciences Discussions ◽

10.5194/hessd-10-12077-2013 ◽

2013 ◽

Vol 10 (10) ◽

pp. 12077-12104 ◽

Cited By ~ 1

Author(s):

A. Eder ◽

M. Exner-Kittridge ◽

P. Strauss ◽

G. Blöschl

Keyword(s):

Sediment Load ◽

Free Water ◽

High Temporal Resolution ◽

Small Stream ◽

Bed Sediments ◽

Small Watersheds ◽

Wave Celerity ◽

Streambed Sediments ◽

Total Sediment ◽

Stream Bed

Abstract. Streams draining small watersheds often exhibit multiple peaking sedigraphs associated with single peaking hydrographs. The process reasons of the multiple sediment peaks are not fully understood but they may be related to the activation of different sediment sources such as the streambed itself where deposited sediments from previous events may be available for resuspension. To understand resuspension of stream bed sediments at the reach scale we artificially flooded the small stream of the HOAL Petzenkirchen catchment in Austria by pumping sediment-free water into the stream. Two short floods were produced and flow, sediment and bromide concentrations were measured at three sites with high temporal resolution. Hydrologically, the two flood events were almost identical. The peak flows decreased from 57 to 7.9 L s−1 and the flow volumes decreased from 17 to 11.3 m3 along the 590 m reach of the stream. However, a considerably smaller sediment load was resuspended and transported during the second flood due to depletion of stream bed sediments. The exception was the middle section of the stream where more sediment was transported during the second flood event which can be explained by differences between flow velocity and wave celerity and the resulting displacement of sediments within the stream. The results indicate that the first peak of the sedigraphs of natural events in this stream is indeed caused by the resuspension of streambed sediments, accounting for up to six percent of the total sediment load depending on total flow volume.

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Sediment Yield and Pollution from Small Watersheds under Changing Climatic Conditions

Engineering Risk in Natural Resources Management ◽

10.1007/978-94-015-8271-1_15 ◽

1994 ◽

pp. 253-265

Author(s):

Istvan Bogardi ◽

Jacques Ganoulis ◽

Lucien Duckstein ◽

Istvan Matyasovszky

Keyword(s):

Sediment Yield ◽

Climatic Conditions ◽

Small Watersheds

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Analysis of Sediment Yield properties in Two Small Watersheds situated under Granite and Gneiss Using GeoWEPP model

Journal of the Association of Korean Geographers ◽

10.25202/jakg.5.1.6 ◽

2016 ◽

Vol 5 (1) ◽

pp. 61-70

Author(s):

Min Seok Kim

Keyword(s):

Sediment Yield ◽

Small Watersheds

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The Effect of Changes in Land Cover on Total Sediment Yield in Peusangan Watershed, Aceh Province

IOP Conference Series Earth and Environmental Science ◽

10.1088/1755-1315/925/1/012029 ◽

2021 ◽

Vol 925 (1) ◽

pp. 012029

Author(s):

E Djunarsjah ◽

M M Julian ◽

N R Alfandi ◽

A A Baskoro

Keyword(s):

Land Cover ◽

Sediment Yield ◽

Erosion Rate ◽

River Flow ◽

Water Infiltration ◽

Delivery Ratio ◽

Sediment Delivery Ratio ◽

Sediment Delivery ◽

Aceh Province ◽

Total Sediment

Abstract The watershed is an area above or higher than a river whose topographical boundaries cause water to flow into the same river. The river flow carries sediment particles that potentially cause silting of the estuary area. The sediment carried by the river flows from the erosion process that occurs in the watershed. Changes in land cover potentially affect the rate of sediment export to rivers due to changes in surface roughness and water infiltration rate to the ground. This study aims to identify the effect of the land cover change on the total sediment yield from the Peusangan Watershed, Aceh Province. The sediment yield is calculated from the erosion rate and the sediment delivery ratio. The erosion rate is modeled using the revised universal soil loss equation, while the sediment delivery ratio is calculated based on the function of the watershed area. From the results of the calculation, in general, the rate of erosion is at a very level where the average erosion rate in 1995 is 26,715 tons/ha/year, in 2005 it is 26,886 tons/ha/year, in 2015 it is 24,959 tons/ha/year and in 2018 amounted to 26,771 tons/ha/year. With a sediment delivery ratio value of 0.180, The total sediment yield was 1,083,148.20 tons in 1995, 1,090,047.94 tons in 2005, 1,011,920.71 tons in 2015, and 1,085,398.35 tons in 2018. The identification results show that the changes in land cover affect the total sediment yield that comes out of the watershed.

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