Relating long-term spatiotemporal trend of coastal turbidity and sedimentation to reservoir construction, and land use and land cover change in the Red River Basin, Vietnam | |
| Author | Pedroso, John Francis Viloria |
| Call Number | AIT Thesis no.WM-24-05 |
| Subject(s) | Turbidity--Vietnam Land use--Vietnam |
| Note | A thesis submitted in partial fulfillment of the requirements for the degree of Master of Science in Water Engineering and Management, School of Engineering and Technology |
| Publisher | Asian Institute of Technology |
| Series Statement | Thesis; no. WM-24-05 |
| Abstract | The construction of large dam-reservoirs, land use and land cover (LULC) changes, and other man-made activities can significantly impact the environment, particularly water resources. The continuous monitoring of the shifts in the trend of water quality parameters, both spatially and temporally, can give an insight to the magnitude and extent of these impacts on the environment. In this study, the spatiotemporal trends of turbidity along Red River coast of Vietnam were analyzed to determine the effects of the series of dams and reservoirs construction, as well as changes in the LULC, on the coastal region of the Red River basin. First, turbidity values at the different river mouths of the Red River were obtained by applying a turbidity retrieval algorithm on cloud-free Landsat satellite images, from 1985 to 2023, of the study area. The long-term, seasonal, and spatial variability of turbidity was then analyzed. It was found that the turbidity values were decreasing over time. This trend was identified in all the river mouths considered. The decrease in the turbidity values was because of the changes in the concentration of sediment in the Red River, associated with the series of large dams-reservoirs development upstream of the river system. Then, the spatiotemporal trend in turbidity was correlated with the sediment concentration at the different river mouths. This was done by developing a sediment transport model in HECRAS. Statistical analysis showed that the strength of correlation between turbidity and the sediment concentration in the different river mouths was decreasing. This indicates that the turbidity values were becoming less influenced by the sediments that are entering the delta region. Finally, a LULC change analysis of the sub-basins in the delta region was done. The changes in each LULC type identified were then correlated with the turbidity values at the respective river mouths in the sub-basin. Statistical analysis showed that the significance of the LULC change to the trend in coastal turbidity increased. This means that the trend in turbidity values in the recent years were more impacted by the changes in LULC in the delta region. |
| Year | 2024 |
| Corresponding Series Added Entry | Asian Institute of Technology. Thesis; no. WM-24-05 |
| Type | Thesis |
| School | School of Engineering and Technology |
| Department | Department of Civil and Infrastucture Engineering (DCIE) |
| Academic Program/FoS | Water Engineering and Management (WM) |
| Chairperson(s) | Shanmugam, Mohana Sundaram;Ho, Huu Loc (Co-Chairperson); |
| Examination Committee(s) | Natthachet Tangdamrongsub;Chaitanya Krishna; |
| Scholarship Donor(s) | Pan Merit Belt and Road Scholarships; |
| Degree | Thesis (M. Sc.) - Asian Institute of Technology, 2024 |