Suspended sediment particle size distribution in Kojour river

Investigation on physical characteristics of suspended sediment is an important subject in river studies. The particle size distribution of the suspended sediment is one of these physical properties represents important links between sources and fluvial mechanisms in the watersheds. However، limited studies have been conducted in field of suspended sediment particle size distribution. The present study therefore aimed to investigate the particle size distribution of suspended sediments in Kojour River within the period of one year. Toward this attempt، 24 suspended sediment samples were collected at intervals of some 15 days. The particle size distribution was determined after necessary preparations by laser scattering particle size of HORIBA LA-950. The results showed that the suspended sediment diameter were in the range of 0. 82 to 353. 55 microns during time of sampling and in different conditions. Also، the silt particles with partial contribution of 97. 68 % had the largest contribution in the suspended sediment load. In addition، the results indicated that the precipitation and sand harvesting plays an important role in increasing the coarse particles of suspended sediment load.