Sediment transport and deposition in deltaic aquatic systems

Abstract

The Ganges-Brahmaputra Delta serves as a critical area that supports both environmental functions and economic development activities. The study investigates how sediment moves and settles down in the delta to study how both natural processes and human activities affect sediment movement. The research aims to measure sediment movement through the study of sediment deposition patterns while investigating how river water flow, tides, and human activities affect the environment. The research used three methods which involved scientists collecting sediment samples from the field and measuring water movement and using computer simulations. The study showed that sediment concentration and flux experienced major changes throughout the year because the monsoon season brought increased sediment flow in the Brahmaputra Branch high-flow channels. The data analysis revealed that suspended sediment concentrations reached their highest point at 520 mg/L, while sediment deposition measurements showed a range between 5 cm and 35 cm across various delta regions. The values of R² of 0.92 attained high accuracy in the model, thus being able to predict sediment concentration. The study reveals how the hydrodynamic forces are very important in the transport of sediments since low flows cause the accumulation of the sediments, whereas high flows cause loss of materials. It is found that the natural movement of sediments must be safeguarded in order to manage the deltas effectively, yet the activities of man, such as the construction of dams and the growth of cities, cause devastating effects. The study should examine the impact of climate change on the ecosystems and must enhance the models of sediment transport to manage the delta area and reclaim land.