**2. Papers Details**

Hu et al. [10] investigate the important aspect of spillover of sediments due to the occurrence of typical tidal processes. The study was devoted to analyzing the case study of the Yangtze River's Estuary. They proposed a 2D numerical model based on the resolution of the depth-averaged 2D shallow water equations. The model is able to simulate the tidal flow, the sediment transport, and eventually the bed evolution in the estuary. Moreover, it allows giving a quantitative estimation regarding the spillover of water and sediment in the analyzed river. They used a high-resolution unstructured grid covering a grea<sup>t</sup> part of the river estuary (more that 600 km) to reproduce the Yangtze Estuary. The validation of the results against field data showed the good performances of the model in reproducing tidal levels, sediment concentration, and depth-averaged velocity.

Botsou et al. [12] analyzed the aspects related to metals' mobility in the water column, focusing their attention on Antinioti Lagoon and Corfu Island. In particular, they investigated the processes responsible for the mobility of metals both in and beyond the transitional fresh–saline water interface. They acquired water samples in two sampling campaigns, as well as surface and core sediments during only the first and second campaigns, respectively. These data were analyzed by means of trace metal analysis. They also performed a statistical analysis to evaluate the significant differences in terms of metal concentrations.

Johnson et al. [13] investigated the role of hurricanes on the modification of the rocky coastline in the Gulf of California, in the Ensenada Almeja in particular. They acquired field data to classify the weight and density of the rocks and performed a study on the hydrodynamic forces needed to move the largest boulders in the site. Geological and lithological characterization of the study area was performed by the authors. Moreover, they collected an aerial photo to map the coastal boulder bed of Ensenada Almeja. In this way, boulder shapes and sizes were evaluated and correlated with the wave heights required to lift the rocks from the bedrock.

Lisi et al. [14] proposed an integrated modeling approach useful for the simulation of sediment dispersion in several types of coastal areas (i.e., semi-enclosed basins and off-shore areas). At first, the attention is focused on the definition of sediment resuspension sources. Then, a definition of the level of accuracy that should be required in modeling activities is proposed. Moreover, they proposed a wide spectrum of possible modeling approaches that could be used by contractors and controlling authorities for scheduling and performing sediment handling activities, giving also a methodological approach useful to read and interpret the numerical results. They also underlined the importance of a modeling–monitoring feedback system.

Kuznetsova and Saprykina [11] analyzed how the beach profile is influenced by the location of underwater bars. They performed this study by using a numerical model with attention paid to the time scale of a given storm. The experiments were numerical; however, they used realistic boundary conditions and wave climate. The results reveal a direct correlation between the location of the underwater bar and the shoreline. Moreover, they found an inverse correlation between the retreat of the shoreline and low-frequency wave heights occurring at the coast.

**Author Contributions:** All authors contributed equally to this manuscript. All authors have read and agreed to the published version of the manuscript.

**Funding:** This research received no external funding.

**Acknowledgments:** We want to express our sincere thankfulness to all the authors and the reviewers.

**Conflicts of Interest:** The authors declare no conflict of interest.
