Version 1
: Received: 23 May 2024 / Approved: 24 May 2024 / Online: 24 May 2024 (13:28:09 CEST)
How to cite:
Khoeun, R.; Sor, R.; Chann, K.; Phy, S. R.; Oeurng, C.; Sok, T. The Impacts of Dams on Streamflow in Tributaries to the Lower Mekong Basin. Preprints2024, 2024051635. https://doi.org/10.20944/preprints202405.1635.v1
Khoeun, R.; Sor, R.; Chann, K.; Phy, S. R.; Oeurng, C.; Sok, T. The Impacts of Dams on Streamflow in Tributaries to the Lower Mekong Basin. Preprints 2024, 2024051635. https://doi.org/10.20944/preprints202405.1635.v1
Khoeun, R.; Sor, R.; Chann, K.; Phy, S. R.; Oeurng, C.; Sok, T. The Impacts of Dams on Streamflow in Tributaries to the Lower Mekong Basin. Preprints2024, 2024051635. https://doi.org/10.20944/preprints202405.1635.v1
APA Style
Khoeun, R., Sor, R., Chann, K., Phy, S. R., Oeurng, C., & Sok, T. (2024). The Impacts of Dams on Streamflow in Tributaries to the Lower Mekong Basin. Preprints. https://doi.org/10.20944/preprints202405.1635.v1
Chicago/Turabian Style
Khoeun, R., Chantha Oeurng and Ty Sok. 2024 "The Impacts of Dams on Streamflow in Tributaries to the Lower Mekong Basin" Preprints. https://doi.org/10.20944/preprints202405.1635.v1
Abstract
The Lower Mekong Basin has had extensive hydropower dam development, which changes hydrologic conditions and threatens the exceptional aquatic biodiver-sity. This study quantifies the degree of hydrologic change between pre-impact (1965-1968) and post-impact (2018-2021) peak hydropower development in two major tributaries of the Lower Mekong Basin, the Sekong River with the fewest dams and the Sesan River with the most dams. Both rivers historically supported migratory fishes. We use daily pre- and post-impact data and the Indicators of Hydrologic Alteration framework to evaluate streamflow changes from dam development. We found signifi-cant changes in low and high magnitude flows in the pre- and post-impact periods of dam development. For the Sekong River, minimum flow had large fluctuations that ranged 290% to 412% more than the pre-impact period, while the Sesan River ranged 120% to 160% more than pre-impact. Dry season flows increased by 200±63% on av-erage in the Sekong River, which is caused by releases from upstream dams. Mean-while, Sesan River dry season flows increased by 100±55% on average. This study in-dicates that seasonal flow changes and extreme flow events occurred more frequently in the two basins following dam construction, which may threaten the ecosystem func-tions.
Environmental and Earth Sciences, Water Science and Technology
Copyright:
This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
