| Gravel riverbeds naturally present a range of sediment size that can span several orders of magnitude. However, fine sediment (i.e., size <2 mm) additions affect sediment transport and are potentially harmful to the river ecology. Limited research has been done to understand the effects of sand addition on gravel bed topography. For this study, we conducted flume experiments testing the effectiveness of topography remote sensing to measure the response of a water-worked gravel bed to varying sand additions and bed flushing. Repeated measurements of the bed topography with through-water photogrammetry show that sand deposits primarily in low-lying areas of the bed, where it is sheltered. Observed changes in bed elevation standard deviation, skewness, and... |
