The measurement of total sediment load in alluvial streams

Information on the share of river bank erosion to the total sediment load at catchment scale by using the fingerprinting approach is important to address our knowledge of erosion processes to better target soil erosion control measures. In particular, river bank erosion is affected by many factors such as spatial and temporal variables and is difficult to quantify the relationship of the share of bank erosion to catchment size and upland erosion rate without extensive fieldwork and data analysis. Potential tracers including geochemical, fallout radionuclides, bulk and compound-specific stable isotopes, and magnetic properties have been used, often in combination with sediment source apportionment. In this worldwide review, the global dataset for percent share of river bank and surface erosion using fingerprinting approach was collected to establish the significance of catchment size and other physical controls on river bank erosion. Google Scholar and Web of Science were used to review research articles that included river bank/subsurface as one of the sediment sources in the study areas. This database showed that the UK (n = 84), USA (n = 14) and Brazil (n = 10) had the highest number of catchments, followed by Iran (n = 4), Southern Zambia (n = 1), Australia (n = 1), Spain (n = 1), Mongolia (n = 1) and Burkina Faso (n = 1) ranging in size from 0.31 to 15000 km2, predominately agriculture. Based on published studies, there is a clear shift of sediment sources from surface erosion to river bank erosion with increasing catchment size. The results show the wide range of relative contributions of surface and river bank sources to the catchment sediment yield around the globe. There are a number of catchments with river bank contribution exceeding 25% and surface contribution exceeding 90% of total sediment loss. This diversity highlights the many factors that influence river bank erosion. In addition to the wide range, sediment source contribution in the range 1-25% from river bank is generally representative around the World. We recommend that long term monitoring of sediment load and surface and river bank sources at nested sites within a catchment are indispensable. Furthermore, limited information on the share of sources often makes it difficult to target mitigation measures reducing sediment loads at the catchment scale.Keywords: Sediment load, catchment size, fingerprinting approach, river bank share

Download Full-text

Application of the modified Einstein procedure for computation of total sediment load

Transactions American Geophysical Union ◽

10.1029/tr037i002p00197 ◽

1956 ◽

Vol 37 (2) ◽

pp. 197 ◽

Cited By ~ 3

Author(s):

K. B. Schroeder ◽

C. H. Hembree

Keyword(s):

Sediment Load ◽

Total Sediment

Download Full-text

Sediment fluxes and sinks for Magela Creek, Northern Territory, Australia

Marine and Freshwater Research ◽

10.1071/mf16107 ◽

2018 ◽

Vol 69 (7) ◽

pp. 1018 ◽

Cited By ~ 3

Author(s):

Wayne D. Erskine ◽

M. J. Saynor ◽

J. M. Boyden ◽

K. G. Evans

Keyword(s):

Suspended Sediment ◽

Sediment Load ◽

Northern Territory ◽

Bed Load ◽

Sediment Yields ◽

Sediment Fluxes ◽

Erosion Rates ◽

Dry Tropics ◽

The World ◽

Total Sediment

Sediment fluxes and sinks based on total sediment load for Magela Creek in the Australian wet–dry tropics have been constructed from detailed measurements of stream suspended sediment (turbidity and suspended sand) and bed load for the 10-year period, 2001–2002 to 2010–2011. This work shows that the sediment trap efficiency of the vegetated wetlands on lower Magela is high at ~89.5%. Sediment fluxes are the lowest in the world because of low soil erosion rates and because upstream floodplains and downstream wetlands trap and store sediment. Bedload yields are less than suspended sediment yields, but the amount of silt and clay is much less than the amount of sand (suspended sand and bedload). All sand is stored upstream of the East Alligator River. Downstream connectivity of sediment movement does not occur. Therefore, sediment moves discontinuously from the upper to the lower catchment.

Download Full-text

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.

Download Full-text