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Vegetation in rivers increases flow resistance and bank stability, reduces bed resistance and flow conveyance, improves water quality, promotes habitat diversity, and alters both mean and turbulent flow. By reducing bed resistance and altering turbulent characteristics, vegetation can change the distribution of deposition and erosion processes. To understand all above mentioned vegetation effects, more research is needed. The goal of this dissertation was to determine the impacts of vegetation on bed resistance and sediment transport and identify a best approach for quantifying vegetation induced friction resistance. To achieve this, both experimental study and numerical simulation were performed. A series of laboratory experiments were conducted in an open channel flume to investigate the impacts of vegetation density on bed resistance and bed load transport for emergent vegetation condition. The bed resistance in a mobile bed channel is equal to the summation of grain and bed form resistances. An attempt has been made to make a separation between grain and bed form resistances, which is challenging and has never been reported in literature. An alternative approach is used to calculate the grain resistance. A new iterative method was derived to calculate the bed form resistance. Empirical relations were formulated to calculate the bed form resistance and bed load transport rate using a newly defined flow parameter that incorporates the vegetation concentration. The bed elevations and bed form height were measured by the Microsoft Kinect 3D Camera. It was found that the height of bed form depends on the vegetation concentration, which determines whether ripple/dune or scour holes are dominant on the bed surface. For sparsely vegetated flows, the bed form height and resistance are decrease rapidly as the vegetation concentration was increased, and they decreased gradually when the vegetation concentration was high. To quantify the vegetation induced friction resistan