色色啦

News

Hydropower in China impacts the flow of the Mekong River

The study shows that the hydropower operations considerably increased dry season flows and decreased wet season flows.
Mekon River livelihoods and food security are closely linked to water.

A study led by researchers from Aalto University in Finland reveals that the hydropower projects in China have caused major river flow changes to the Mekong River since the year 2011. An analysis of river flows in Northern Thailand indicates that the hydropower operations considerably increased dry season flows and decreased wet season flows. Furthermore, the study shows that the dry season flows have also become increasingly variable.

The river flow impacts were largest in 2014 after completion of the Nuozhadu dam, the largest hydropower project in the Mekong Basin, and the impacts were observable over 2000 km downstream in Cambodia. The hydropower operations dampened the Mekong River鈥檚 annual flood, which is a key driver of the ecological productivity of the river.

鈥淭he river flow changes are feared to affect the ecological productivity of the river and thus the livelihoods, economy and food security of the downstream people. In particular the impacts on fishing are a major concern because fish and other aquatic animals play a major role in the local and regional economy and food supply,鈥 says researcher Timo R盲s盲nen.

He continues: 鈥淗owever, the ecological and social consequences of the hydropower operations are not yet well understood and more research is needed. The downstream countries are also building hydropower stations and the cumulative impacts need further attention. Therefore the research highlights the importance of strong transboundary cooperation between upstream and downstream countries for understanding and mitigating the negative consequences.鈥

The Mekong River is one of the world鈥檚 largest rivers and it provides livelihoods and food security for millions of people. The energy demand is growing rapidly in the region, and in recent years China has built large hydropower projects in the upper reaches of the Mekong River. This has raised concerns about the potentially harmful impacts on the river and downstream countries.

Despite these concerns the upstream hydropower companies have not shared publicly information about the expected or observed downstream impacts of the hydropower development.

The research article was published in Journal of Hydrology in December 2016.

Article:
R盲s盲nen, T.A., Someth, P., Lauri, H., Koponen, J., Sarkkula, J. and Kummu, M., 2017. Journal of Hydrology, 545, 28-41. DOI: 10.1016/j.jhydrol.2016.12.023

More information: 
PhD Timo A. R盲s盲nen
Aalto-yliopisto
timo.rasanen@aalto.fi
p. 040 518 2752

  • Updated:
  • Published:
Share
URL copied!

Read more news

Two students and a professor sitting around a table, talking and looking at laptop screen.
Research & Art, Studies Published:

Call for doctoral student tutors, September 2025

Sign-up to be a tutor for new doctoral students as part of the Aalto Doctoral Orientation Days!
Abstract image of glowing teal shapes and pink blocks on a striped yellow and green surface, with a dark background.
Research & Art Published:

Researchers turn energy loss into a way of creating lossless photonics-based devices

Turning energy loss from a fatal flaw into a dial for fine-tuning new states of matter into existence could yield better laser, quantum and optical technology.
A person reads a book in front of a large illuminated 'A' sign.
Press releases Published:

Half of highly educated immigrants find employment through Espoo and Aalto鈥檚 collaboration

The exceptional employment outcomes are the result of collaboration, in which service design research has played a key role.
An illustrative figure comparing disease-induced immunity (left) and randomly distributed immunity (right) in the same network. Illustration: Jari Saram盲ki's research group, Aalto UIniversity.
Research & Art Published:

Herd immunity may not work how we think

A new study from researchers at Aalto University suggests that our picture of herd immunity may be incomplete 鈥 and that understanding how people are connected could be just as important as knowing how many are immune.