Articles | Volume 13, issue 5
https://doi.org/10.5194/esurf-13-959-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/esurf-13-959-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
25 Sep 2025
Research article |
| 25 Sep 2025
| 25 Sep 2025
Shape evolution of bulk sediment in headwater streams: effects of rock type and particle size
Naoya O. Takahashi
CORRESPONDING AUTHOR
Department of Earth Science, Tohoku University, Sendai, 980-0845, Japan
Daisuke Ishimura
Department of Geography, Tokyo Metropolitan University, Hachioji, Tokyo, 192–0397, Japan
present address: Graduate School of Science, Department of Earth Sciences, Chiba University, Chiba 263-8522, Japan
Keitaro Yamada
Research Centre for Palaeoclimatology, Ritsumeikan University, Kusatsu, Shiga, 525-8577, Japan
Ryoga J. Ohta
The Institute of Science and Engineering, Chuo University, Tokyo, 112-8551, Japan
present address: Faculty of Humanities, Niigata University, Niigata 950-2181, Japan
Yuki Arai
Department of Earth Science, Tohoku University, Sendai, 980-0845, Japan
Yuki Yamane
Department of Earth Science, Tohoku University, Sendai, 980-0845, Japan
Cited articles
Attal, M. and Lavé, J.: Changes of bedload characteristics along the Marsyandi River (central Nepal): Implications for understanding hillslope sediment supply, sediment load evolution along fluvial networks, and denudation in active orogenic belts, in: Tectonics, Climate, and Landscape Evolution, Geological Society of America, https://doi.org/10.1130/2006.2398(09), 2006.
Attal, M. and Lavé, J.: Pebble abrasion during fluvial transport: Experimental results and implications for the evolution of the sediment load along rivers, J. Geophys. Res., 114, 2009JF001328, https://doi.org/10.1029/2009JF001328, 2009.
Auel, C., Albayrak, I., Sumi, T., and Boes, R. M.: Sediment transport in high-speed flows over a fixed bed: 1. Particle dynamics, Earth Surf Processes Landf, 42, 1365–1383, https://doi.org/10.1002/esp.4128, 2017.
Barrett, P. J.: The shape of rock particles, a critical review, Sedimentology, 27, 291–303, https://doi.org/10.1111/j.1365-3091.1980.tb01179.x, 1980.
Bagheri, G. H., Bonadonna, C., Manzella, I., and Vonlanthen, P.: On the characterization of size and shape of irregular particles, Powder Technology, 270, 141–153, https://doi.org/10.1016/j.powtec.2014.10.015, 2015.
Benn, D. I. and Ballantyne, C. K.: Reconstructing the transport history of glacigenic sediments: a new approach based on the co-variance of clast form indices, Sedimentary Geology, 91, 215–227, https://doi.org/10.1016/0037-0738(94)90130-9, 1994.
Blott, S. J. and Pye, K.: Particle shape: a review and new methods of characterization and classification, Sedimentology, 55, 31–63, https://doi.org/10.1111/j.1365-3091.2007.00892.x, 2008.
Bodek, S. and Jerolmack, D. J.: Breaking down chipping and fragmentation in sediment transport: the control of material strength, Earth Surf. Dynam., 9, 1531–1543, https://doi.org/10.5194/esurf-9-1531-2021, 2021.
Bradley, D. and Roth, G.: Adaptive Thresholding using the Integral Image, Journal of Graphics Tools, 12, 13–21, https://doi.org/10.1080/2151237X.2007.10129236, 2007.
Bray, E. N., Litwin-Miller, K., Cardona, M., Pettyjohn, S., and Sklar, L. S.: Influence of particle lithology, size and angularity on rates and products of bedload wear: An experimental study, Earth Surf Processes Landf, 49, 4972–4990, https://doi.org/10.1002/esp.6007, 2024.
Briggs, L. I., McCulloch, D. S., and Moser, F.: The hydraulic shape of sand particles, Journal of Sedimentary Research, 32, 645-656, https://doi.org/10.1306/74D70D44-2B21-11D7-8648000102C1865D, 1962.
Brook, M. S. and Lukas, S.: A revised approach to discriminating sediment transport histories in glacigenic sediments in a temperate alpine environment: a case study from Fox Glacier, New Zealand, Earth Surf Processes Landf, 37, 895–900, https://doi.org/10.1002/esp.3250, 2012.
Buchwald, T., Ditscherlein, R., and Peuker, U. A.: Correlation of 2D and 3D particle properties with simulated particle imaging dataset, Particuology, 96, 152–170, https://doi.org/10.1016/j.partic.2024.10.008, 2025.
Cassel, M., Lavé, J., Recking, A., Malavoi, J.-R., and Piégay, H.: Bedload transport in rivers, size matters but so does shape, Sci. Rep., 11, 508, https://doi.org/10.1038/s41598-020-79930-7, 2021.
Cassel, M., Piégay, H., Lavé, J., Vaudor, L., Hadmoko Sri, D., Wibiwo Budi, S., and Lavigne, F.: Evaluating a 2D image-based computerized approach for measuring riverine pebble roundness, Geomorphology, 311, 143–157, https://doi.org/10.1016/j.geomorph.2018.03.020, 2018.
Cattapan, A., Gurini, A., Paron, P., Ballio, F., and Franca, M. J.: A method for segmentation of pebble images in the presence of shadows, Earth Surf Processes Landf, 49, 5202–5212, https://doi.org/10.1002/esp.6027, 2024.
Chatanantavet, P., Whipple, K. X., Adams, M. A., and Lamb, M. P.: Experimental study on coarse grain saltation dynamics in bedrock channels, JGR Earth Surface, 118, 1161–1176, https://doi.org/10.1002/jgrf.20053, 2013.
Cox, E. P.: A method of assigning numerical and percentage values to the degree of roundness of sand grains, Journal of Paleontology, 1, 179–183, 1927.
Crameri, F.: Scientific colour maps (8.0.1), Zenodo [data set], https://doi.org/10.5281/zenodo.8409685, 2023.
Deal, E., Venditti, J. G., Benavides, S. J., Bradley, R., Zhang, Q., Kamrin, K., and Perron, J. T.: Grain shape effects in bed load sediment transport, Nature, 613, 298–302, https://doi.org/10.1038/s41586-022-05564-6, 2023.
Demiral, D., Albayrak, I., Turowski, J. M., and Boes, R. M.: Particle saltation trajectories in supercritical open channel flows: Roughness effect, Earth Surf Processes Landf, 47, 3588–3610, https://doi.org/10.1002/esp.5475, 2022.
DiBiase, R. A., Neely, A. B., Whipple, K. X., Heimsath, A. M., and Niemi, N. A.: Hillslope Morphology Drives Variability of Detrital10 Be Erosion Rates in Steep Landscapes, Geophysical Research Letters, 50, e2023GL104392, https://doi.org/10.1029/2023GL104392, 2023.
Dietrich, W. E.: Settling velocity of natural particles, Water Resources Research, 18, 1615–1626, https://doi.org/10.1029/WR018i006p01615, 1982.
Dingle, E. H., Kusack, K. M., and Venditti, J. G.: The gravel-sand transition and grain size gap in river bed sediments, Earth-Science Reviews, 222, 103838, https://doi.org/10.1016/j.earscirev.2021.103838, 2021.
Domokos, G., Jerolmack, D. J., Sipos, A. Á., and Török, Á.: How River Rocks Round: Resolving the Shape-Size Paradox, PLoS ONE, 9, e88657, https://doi.org/10.1371/journal.pone.0088657, 2014.
Domokos, G., Kun, F., Sipos, A. Á., and Szabó, T.: Universality of fragment shapes, Sci. Rep., 5, 9147, https://doi.org/10.1038/srep09147, 2015.
Fehér, E., Havasi-Tóth, B., and Ludmány, B.: Fully spherical 3D datasets on sedimentary particles: Fast measurement and evaluation, CEuGeol, 65, 111–121, https://doi.org/10.1556/24.2022.00124, 2023.
Ferguson, R. I. and Church, M.: A Simple Universal Equation for Grain Settling Velocity, Journal of Sedimentary Research, 74, 933–937, https://doi.org/10.1306/051204740933, 2004.
Ferguson, R., Hoey, T., Wathen, S., and Werritty, A.: Field evidence for rapid downstream fining of river gravels through selective transport, Geol., 24, 179, https://doi.org/10.1130/0091-7613(1996)024<0179:FEFRDF>2.3.CO;2, 1996.
Frostick, L. E. and Reid, I.: Sorting mechanisms in coarse-grained alluvial sediments: fresh evidence from a basalt plateau gravel, Kenya, JGS, 137, 431–441, https://doi.org/10.1144/gsjgs.137.4.0431, 1980.
Hack, J. T.: Studies of Longitudinal Stream Profiles in Virginia and Maryland, United States Geological Survey Professional paper, 294-B, 45–97, https://doi.org/10.3133/pp294B, 1957.
Hattanji, T., Kodama, R., Takahashi, D., Tanaka, Y., Doshida, S., and Furuichi, T.: Migration of channel heads by storm events in two granitic mountain basins, western Japan: Implication for predicting location of landslides, Geomorphology, 393, 107943, https://doi.org/10.1016/j.geomorph.2021.107943, 2021.
Hattingh, J. and Illenberger, W. K.: Shape sorting of flood-transported synthetic clasts in a gravel bed river, Sedimentary Geology, 96, 181–190, https://doi.org/10.1016/0037-0738(94)00139-L, 1995.
Hirata, Y., Chigira, M., and Chen, Y.: Spheroidal weathering of granite porphyry with well-developed columnar joints by oxidation, iron precipitation, and rindlet exfoliation, Earth Surf Processes Landf, 42, 657–669, https://doi.org/10.1002/esp.4008, 2017.
Hodge, R. A., Voepel, H., Leyland, J., Sear, D. A., and Ahmed, S.: X-ray computed tomography reveals that grain protrusion controls critical shear stress for entrainment of fluvial gravels, Geology, 48, 149–153, https://doi.org/10.1130/G46883.1, 2020.
Ishimura, D. and Hiramine, R.: Dispersion, fragmentation, abrasion, and organism attachment of drift pumice from the 2021 Fukutoku-Oka-no-Ba eruption in Japan, Prog. Earth Planet. Sci., 12, 5, https://doi.org/10.1186/s40645-024-00678-z, 2025.
Ishimura, D. and Yamada, K.: Palaeo-tsunami inundation distances deduced from roundness of gravel particles in tsunami deposits, Sci. Rep., 9, 10251, https://doi.org/10.1038/s41598-019-46584-z, 2019.
Japan Meteorological Agency: Data and materials, https://www.jma.go.jp/jma/menu/menureport.html, last access: 30 January 2025.
Jerolmack, D. J. and Brzinski, T. A.: Equivalence of abrupt grain-size transitions in alluvial rivers and eolian sand seas: A hypothesis, Geology, 38, 719–722, https://doi.org/10.1130/G30922.1, 2010.
Jones, L. S. and Humphrey, N. F.: Weathering-controlled abrasion in a coarse-grained, meandering reach of the Rio Grande: Implications for the rock record, Geological Society of America Bulletin, https://doi.org/10.1130/0016-7606(1997)109<1080:WCAIAC>2.3.CO;2, 1997.
Knighton, A. D.: Longitudinal changes in the size and shape of stream bed material: Evidence of variable transport conditions, Catena, 9, 25–34, https://doi.org/10.1016/S0341-8162(82)80003-9, 1982.
Kodama, Y.: Downstream Changes in the Lithology and Grain Size of Fluvial Gravels, the Watarase River, Japan: Evidence of the Role of Abrasion in Downstream Fining, SEPM JSR, 64A, https://doi.org/10.1306/D4267D0C-2B26-11D7-8648000102C1865D, 1994.
Krumbein, W. C.: The Effects of Abrasion on the Size, Shape and Roundness of Rock Fragments, The Journal of Geology, 49, 482–520, https://doi.org/10.1086/624985, 1941a.
Krumbein, W. C.: Measurement and Geological Significance of Shape and Roundness of Sedimentary Particles, SEPM JSR, 11, https://doi.org/10.1306/D42690F3-2B26-11D7-8648000102C1865D, 1941b.
Kuenen, P. H.: Experimental Abrasion of Pebbles: 2. Rolling by Current, The Journal of Geology, 64, 336–368, https://doi.org/10.1086/626370, 1956.
Larsen, I. J. and Montgomery, D. R.: Landslide erosion coupled to tectonics and river incision, Nature Geosci., 5, 468–473, https://doi.org/10.1038/ngeo1479, 2012.
Lindsey, D. A., Langer, W. H., and Van Gosen, B. S.: Using pebble lithology and roundness to interpret gravel provenance in piedmont fluvial systems of the Rocky Mountains, USA, Sedimentary Geology, 199, 223–232, https://doi.org/10.1016/j.sedgeo.2007.02.006, 2007.
Litwin Miller, K. and Jerolmack, D.: Controls on the rates and products of particle attrition by bed-load collisions, Earth Surf. Dynam., 9, 755–770, https://doi.org/10.5194/esurf-9-755-2021, 2021.
Litwin Miller, K., Szabó, T., Jerolmack, D. J., and Domokos, G.: Quantifying the significance of abrasion and selective transport for downstream fluvial grain size evolution, JGR Earth Surface, 119, 2412–2429, https://doi.org/10.1002/2014JF003156, 2014.
MacCarthy, G. R.: The rounding of beach sands, American Journal of Science, 25, 205–224, 1933.
MacKenzie, L. G., Eaton, B. C., and Church, M.: Breaking from the average: Why large grains matter in gravel-bed streams, Earth Surf Processes Landf, 43, 3190–3196, https://doi.org/10.1002/esp.4465, 2018.
Mackin, H. J.: Concept of the graded river, Geol. Soc. America Bull., 59, 463, https://doi.org/10.1130/0016-7606(1948)59[463:COTGR]2.0.CO;2, 1948.
McBride, E. F. and Picard, M. D.: Downstream Changes in Sand Composition, Roundness, and Gravel Size in a Short-headed, High-Gradient Stream, Northwestern Italy, SEPM JSR, 57, https://doi.org/10.1306/212F8CD3-2B24-11D7-8648000102C1865D, 1987.
McPherson, H. J.: Downstream Changes in Sediment Character in a High Energy Mountain Stream Channel, Arctic and Alpine Research, 3, 65, https://doi.org/10.2307/1550383, 1971.
Mills, H. H.: Downstream Rounding of Pebbles–A Quantitative Review, SEPM JSR, 49, https://doi.org/10.1306/212F7720-2B24-11D7-8648000102C1865D, 1979.
Mueller, E. R., Smith, M. E., and Pitlick, J.: Lithology-controlled evolution of stream bed sediment and basin-scale sediment yields in adjacent mountain watersheds, Idaho, USA, Earth Surf Processes Landf, 41, 1869–1883, https://doi.org/10.1002/esp.3955, 2016.
Novák-Szabó, T., Sipos, A. Á., Shaw, S., Bertoni, D., Pozzebon, A., Grottoli, E., Sarti, G., Ciavola, P., Domokos, G., and Jerolmack, D. J.: Universal characteristics of particle shape evolution by bed-load chipping, Sci. Adv., 4, eaao4946, https://doi.org/10.1126/sciadv.aao4946, 2018.
Otsu, N.: A Threshold Selection Method from Gray-Level Histograms, IEEE Trans. Syst., Man, Cybern., 9, 62–66, https://doi.org/10.1109/TSMC.1979.4310076, 1979.
Pál, G., Domokos, G., and Kun, F.: Curvature flows, scaling laws and the geometry of attrition under impacts, Sci. Rep., 11, 20661, https://doi.org/10.1038/s41598-021-00030-1, 2021.
Paola, C., Parker, G., Seal, R., Sinha, S. K., Southard, J. B., and Wilcock, P. R.: Downstream Fining by Selective Deposition in a Laboratory Flume, Science, 258, 1757–1760, https://doi.org/10.1126/science.258.5089.1757, 1992.
Parker, G., Wilcock, P. R., Paola, C., Dietrich, W. E., and Pitlick, J.: Physical basis for quasi-universal relations describing bankfull hydraulic geometry of single-thread gravel bed rivers, J. Geophys. Res., 112, 2006JF000549, https://doi.org/10.1029/2006JF000549, 2007.
Parker, G., An, C., Lamb, M. P., Garcia, M. H., Dingle, E. H., and Venditti, J. G.: Dimensionless argument: a narrow grain size range near 2 mm plays a special role in river sediment transport and morphodynamics, Earth Surf. Dynam., 12, 367–380, https://doi.org/10.5194/esurf-12-367-2024, 2024.
Petit, F., Houbrechts, G., Peeters, A., Hallot, E., Van Campenhout, J., and Denis, A.-C.: Dimensionless critical shear stress in gravel-bed rivers, Geomorphology, 250, 308–320, https://doi.org/10.1016/j.geomorph.2015.09.008, 2015.
Pettijohn, F. J.: Sedimentary rocks, Harper & Brothers, New York, USA, 526 pp., 1949.
Pettijohn, F. J. and Lundahl, A. C.: Shape and roundness of Lake Erie beach sands, Journal of Sedimentary Research, 13, 69–78, https://doi.org/10.1306/D426919D-2B26-11D7-8648000102C1865D, 1943.
Pfeiffer, A. M., Morey, S., Karlsson, H. M., Fordham, E. M., and Montgomery, D. R.: Survival of the Strong and Dense: Field Evidence for Rapid, Transport-Dependent Bed Material Abrasion of Heterogeneous Source Lithology, JGR Earth Surface, 127, e2021JF006455, https://doi.org/10.1029/2021JF006455, 2022.
Pokhrel, P., Attal, M., Sinclair, H. D., Mudd, S. M., and Naylor, M.: Downstream rounding rate of pebbles in the Himalaya, Earth Surf. Dynam., 12, 515–536, https://doi.org/10.5194/esurf-12-515-2024, 2024.
Powers, M. C.: A New Roundness Scale for Sedimentary Particles, SEPM JSR, 23, https://doi.org/10.1306/D4269567-2B26-11D7-8648000102C1865D, 1953.
Quick, L., Sinclair, H. D., Attal, M., and Singh, V.: Conglomerate recycling in the Himalayan foreland basin: Implications for grain size and provenance, GSA Bulletin, 132, 1639–1656, https://doi.org/10.1130/B35334.1, 2020.
Rice, S.: Which tributaries disrupt downstream fining along gravel-bed rivers?, Geomorphology, 22, 39–56, https://doi.org/10.1016/S0169-555X(97)00052-4, 1998.
Rice, S. and Church, M.: Grain size along two gravel-bed rivers: statistical variation, spatial pattern and sedimentary links, Earth Surf. Process. Landforms, 23, 345–363, https://doi.org/10.1002/(SICI)1096-9837(199804)23:4<345::AID-ESP850>3.0.CO;2-B, 1998.
Roering, J. J., Perron, J. T., and Kirchner, J. W.: Functional relationships between denudation and hillslope form and relief, Earth and Planetary Science Letters, 264, 245–258, https://doi.org/10.1016/j.epsl.2007.09.035, 2007.
Roussillon, T., Piégay, H., Sivignon, I., Tougne, L., and Lavigne, F.: Automatic computation of pebble roundness using digital imagery and discrete geometry, Computers & Geosciences, 35, 1992–2000, https://doi.org/10.1016/j.cageo.2009.01.013, 2009.
Russell, R. D. and Taylor, R. E.: Roundness and Shape of Mississippi River Sands, The Journal of Geology, 45, 225–267, https://doi.org/10.1086/624526, 1937.
Sak, P. B., Navarre-Sitchler, A. K., Miller, C. E., Daniel, C. C., Gaillardet, J., Buss, H. L., Lebedeva, M. I., and Brantley, S. L.: Controls on rind thickness on basaltic andesite clasts weathering in Guadeloupe, Chemical Geology, 276, 129–143, https://doi.org/10.1016/j.chemgeo.2010.05.002, 2010.
Schmeeckle, M. W., Nelson, J. M., Pitlick, J., and Bennett, J. P.: Interparticle collision of natural sediment grains in water, Water Resources Research, 37, 2377–2391, https://doi.org/10.1029/2001WR000531, 2001.
Shobe, C. M., Turowski, J. M., Nativ, R., Glade, R. C., Bennett, G. L., and Dini, B.: The role of infrequently mobile boulders in modulating landscape evolution and geomorphic hazards, Earth-Science Reviews, 220, 103717, https://doi.org/10.1016/j.earscirev.2021.103717, 2021.
Sklar, L. S.: Grain Size in Landscapes, Annual Review of Earth and Planetary Sciences, 52, 663–692, https://doi.org/10.1146/annurev-earth-052623-075856, 2024.
Sklar, L. S. and Dietrich, W. E.: A mechanistic model for river incision into bedrock by saltating bed load, Water Resources Research, 40, 2003WR002496, https://doi.org/10.1029/2003WR002496, 2004.
Sklar, L. S., Dietrich, W. E., Foufoula-Georgiou, E., Lashermes, B., and Bellugi, D.: Do gravel bed river size distributions record channel network structure?, Water Resources Research, 42, 2006WR005035, https://doi.org/10.1029/2006WR005035, 2006.
Sklar, L. S., Riebe, C. S., Genetti, J., Leclere, S., and Lukens, C. E.: Downvalley fining of hillslope sediment in an alpine catchment: implications for downstream fining of sediment flux in mountain rivers, Earth Surf Processes Landf., 45, 1828–1845, https://doi.org/10.1002/esp.4849, 2020.
Smith, H. E. J., Monsalve, A. D., Turowski, J. M., Rickenmann, D., and Yager, E. M.: Controls of local grain size distribution, bed structure and flow conditions on sediment mobility, Earth Surf Processes Landf., 48, 1990–2004, https://doi.org/10.1002/esp.5599, 2023.
Sneed, E. D. and Folk, R. L.: Pebbles in the Lower Colorado River, Texas a Study in Particle Morphogenesis, The Journal of Geology, 66, 114–150, https://doi.org/10.1086/626490, 1958.
Sternberg, H.: Untersuchungen über längen- und querprofil geschiebeführender Flüsse, Zeitschrift für bauwesen, 25, 483–506, 1875.
Takahashi, N., Ishimura, D., Yamada, K., Ohta, R., Arai, Y., and Yamane, Y.: Shape of natural and manually crushed particles collected from a headwater stream in Tsugaru, Japan, figshare [data set], https://doi.org/10.6084/m9.figshare.28424138, 2025.
Takahashi, N. O.: Relative role of rock erodibility and sediment load in setting channel slope of mountain rivers, Earth Surf Processes Landf., 50, e70017, https://doi.org/10.1002/esp.70017, 2025.
Takashimizu, Y. and Iiyoshi, M.: New parameter of roundness R: circularity corrected by aspect ratio, Prog. in Earth and Planet. Sci., 3, 2, https://doi.org/10.1186/s40645-015-0078-x, 2016.
Tripathi, P., Lee, S. J., Lee, C. H., and Shin, M.: Towards 3D Shape Estimation from 2D Particle Images: A State-of-the-Art Review and Demonstration, Kona, 42, 37–56, https://doi.org/10.14356/kona.2025017, 2025.
Tsushima, K. and Uemura, F.: Explanatory text of the geological map of Japan, Scale 1:50000, Kodomari, Geological Survey of Japan, 43 pp., 1959.
Uemura, F., Tsushima, K., and Saito, M.: Explanatory text of the geological map of Japan, Scale 1:50000, Kodomari, Geological Survey of Japan, 39 pp., 1959.
Vázquez‐Tarrío, D., Recking, A., Liébault, F., Tal, M., and Menéndez‐Duarte, R.: Particle transport in gravel‐bed rivers: Revisiting passive tracer data, Earth Surf Processes Landf, 44, 112–128, https://doi.org/10.1002/esp.4484, 2019.
Villarino, M. B.: Ramanujan's Perimeter of an Ellipse, arXiv [preprint], https://doi.org/10.48550/arXiv.math/0506384, 20 June 2005.
Wadell, H.: Volume, Shape, and Roundness of Rock Particles, The Journal of Geology, 40, 443–451, https://doi.org/10.1086/623964, 1932.
Wentworth, C. K.: A Laboratory and Field Study of Cobble Abrasion, The Journal of Geology, 27, 507–521, https://doi.org/10.1086/622676, 1919.
Wentworth, C. K.: A field study of the shapes of river pebbles, in: Contributions to the geography of the United States, United States Geological Survey, https://pubs.usgs.gov/publication/b730C (last access: 24 September 2025), 1923.
Yamada, K.: Rgarins, GitHub[software], https://github.com/keitaroyamada/Rgrains (last access: 24 September 2025), 2024.
Zhang, Z. and Ghadiri, M.: Impact attrition of particulate solids. Part 2: Experimental work, Chemical Engineering Science, 57, 3671–3686, https://doi.org/10.1016/S0009-2509(02)00241-5, 2002.
Zheng, J. and Hryciw, R. D.: Traditional soil particle sphericity, roundness and surface roughness by computational geometry, Géotechnique, 65, 494–506, https://doi.org/10.1680/geot.14.P.192, 2015.
Short summary
Changes in sediment mass is accompanied by shape change. We studied downstream changes in particle shape near a channel head using image-based analysis. Although the particles tended to become smoother and more circular, such trend was significantly disrupted by the addition of rock fragment supplied from hillslopes or detached from larger particles during transport. Our findings indicated the dominant process that determine particle shape changes over short distance in headwater streams.
Changes in sediment mass is accompanied by shape change. We studied downstream changes in...
