A comparison between the laboratory and field models of the peer-bazar river for examining the sediment transport estimation and its effect on life expectancy and the environment of the Anzali estuary

Energy of flow is the main factor of sediment particle displacement in the water channel. The physical representation of the flow energy can be presumed at water depth، velocity، flow rate and their relationship. Assessment of the variation of the flow depth by assuming little changes on the bed or its dip against flow depth in laboratory and field is of particular importance. Therefore، investigating the effect of flow height changes on amount of sediment transport in Anzali wetland was taken into consideration. To achieve this goal، Pir-Bazar River and then Pir-Bazar Roga which are led to the Anzali wetland، were selected. In this research، field study based on sampling of bed sediments and measuring hydraulic characteristics such as depth، velocity and therefore the flow rate at different cross section were measured by Q-liner. The results of the field outcome and also its comparison with the experimental results show that by increasing water depth in Pir-Bazar station، the height of flow near the wetlands has been increased a little due to the meandering river and energy depreciation. This little water depth increment causes sediment to be transported to Pir-Bazar Roga branch and the early part of the wetland while significant amount of sediment transports from Pir-Bazar Roga to wetland is not lead. With regard to the adaption of the field outcome and laboratory study and the amount of the existing discharge rating curve during a year (90-91) at Pir-Bazar station، approximately 212 tons of sediment has passed through Pir-Bazar River near wetland and entered to the wetland. This amount of sediment transport is one of the most important factors on life expectancy and the sustainability environment of the Anzali estuary.