Monitoring of Suspended Sediment Concentration by Alternative Methods: Scientific and Technological Trends and Application Challenges

This study presents an integrative review of the methods used to estimate and monitor suspended sediment concentration (SSC), an important parameter for understanding erosive processes, river dynamics, reservoir lifespan, and water quality. The search in the Scopus, Web of Science, and SciELO databases covered studies published between 1992 and 2025. Of the 452 records identified, 269 were considered eligible after removing duplicates. The studies were grouped into traditional methods, optical, acoustic, remote sensing, optical–acoustic integrations, uncommon methods, and parallel measurements. Traditional methods predominated (95 studies), followed by remote sensing (84), optical (40), and acoustic (17). Traditional methods are reliable but require high logistical effort and have low temporal resolution. Optical sensors allow continuous monitoring, although they require local calibration. Acoustic methods better represent the vertical and transversal distribution of SSC but are sensitive to particle characteristics. Remote sensing expands spatial and temporal coverage but depends on image resolution and atmospheric conditions. Therefore, it is concluded that no method is universally superior, and the choice should consider the objective, environment, scale, and acceptable uncertainty. Traditional methods remain relevant as they serve as a reference for the others.