**1. Introduction**

In recent years, increasing attention has been paid to water quality and environmental aspects related to sediment transport driven by both ambient forcing and human activities. The increasing attention paid to this wide topic is also exacerbated by the exploitation of the coastal zone for economic, touristic and social reasons (e.g., [1]). Indeed, estuarine, coastal, and harbor areas often undergo operations that temporarily increase sediment transport, e.g., to nourish beaches, to maintain navigation channels, and to remove contaminated sediment primarily to support their use. For example, beach maintenance is required to counteract erosion processes that degrade beach quality. Sand has to be dredged and moved to nourish beaches (e.g., [2]). Moreover, harbor areas and navigation channels require maintenance dredging (e.g., [3]) to allow the regular circulation of the vessels and, in some cases, to remove contaminated sediments.

Particular interest is focused on water quality and environmental aspects related to sediment transport driven by anthropogenic activities. The impact of these activities on water quality (e.g., [4]) and on the human health is a significant public concern (e.g., [5]). Therefore, it is important to have reliable tools able to provide a realistic forecasts of the plume dispersion (e.g., [6–9]). Hence, much research is needed related to the sediment processes, transport, and related environmental aspects of marine sediments.

The aim of this Special Issue is to collect novel research results to improve knowledge and to propose new tools in this field. The issue collected five papers that cover different aspects of coastal and ocean engineering, chemical oceanography, geology, and geomorphology using different approaches and instruments. Some of the studies used numerical models [10,11], others acquired and analyzed field data regarding chemical [12] or geomorphological aspects of the ocean [13] while Lisi et al. [14] suggested a mathematical modeling framework to analyze the effects of sediment handling operations.

The core aspects of each paper are synthesized in the following section.
