The last decades have shown an increase in the frequency and magnitude of floods (Blöschl et al. 2020). The intensification of flood regimes will likely enhance rivers’ capacity to erode and transport sediment. Sedimentary properties, such as texture, porosity and geochemistry ar
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The last decades have shown an increase in the frequency and magnitude of floods (Blöschl et al. 2020). The intensification of flood regimes will likely enhance rivers’ capacity to erode and transport sediment. Sedimentary properties, such as texture, porosity and geochemistry are crucial factors that affect the economic and ecologic values of overbank zones. Moreover, understanding of sediment fluxes and pathways is also key in predicting the distribution of adhesive heavy metal contaminants, microplastics and forever PFAS chemicals. Yet, modelled estimates of sediment transport and overbank deposition are notoriously inaccurate. A recent experimental study of bed load transport suggested up to a factor 5 attributable to the shape of particles (Deal et al., 2023). Here we show that the shape of sand grains is probably also a critically overlooked factor in suspended sediment transport. Its effects are observed from lateral-distance sorting in overbank deposits from different catchments. We used hydraulic modelling to further test our initial observations and to explore the magnitude of changes in sediment transport that are potentially caused by grain shape.