LAUSR

As a high-precision survey method, seismic surveying has been increasingly applied to inland water research, although its application to artificial reservoirs has remained limited. As a special artificial water body, reservoirs have important effects on the fluvial transport of material from land to ocean, and inevitably have complex terrain which can complicate and distort the results of seismic surveys. Therefore, there are still some problems need to be resolved in the application of seismic surveys in reservoirs with complex terrain. For this study, the Dongfeng Reservoir located in the upper reaches of the Wujiang River was chosen as an example to test the seismic survey method. Our testing showed that (1) because of the complex underwater terrain, the signal-to-noise ratio of the echo signal in canyon reservoir is low, making it difficult to determine sediment layers thicknesses in some areas; and (2) due to the large spatial heterogeneity of sediment distribution, insufficient density of cross-sections can lead to inaccurate interpolation results. To improve the accuracy of calculations, a mathematical method was used. Ultimately, the total burial mass of sediment was estimated at 2.85 × 107 tons, and the average burial rates of total organic carbon, total phosphorus, and total nitrogen were estimated at 0.194, 0.011, and 0.014 g cm−2 year−1, respectively. These values were close to the results of previous studies and hydrographic station data, indicating that seismic survey can be a reliable and efficient method for the mapping of reservoirs.