Study of suspended particle size in relation with discharge and sediment concentration in a mountain catchment

Abstract

This study shows presents the dynamics of suspended sediment transport at the the results of suspended sediment sampling at three gauging stations in the Vallcebre experimental basins (Eastern Pyrenees). The paper analyses particle size distribution of the automatically collected sediment samples during three seasons: The work analyses particle size characteristics of sediments collected by three automatic samplers in different seasons (spring, summer and autumn). Highest Peak suspended solids concentrations measured exceeded 100 g l- 1. Texture of The transported sediments consist consisted mainly of fine silt, with low percentages of clay and very low fractions of fine sand. PPositive correlationss werewere found between particle size and water discharge, whereas correlations between particle size and sediment concentration were only were hardly significant in one of the catchment. In the study area, the particle size of transported suspended sediments, largely depends on the lithological material of the catchments. However, hydrological this headwaters area, the original material source is the main control of the particle size in suspended sediments transported by streams, although the transport processes, deposition and re-erosion phenomena, produced their fractioning and erosion of particles.