The article presented this week in journal club covered the issue of growing hydropower in three of the world’s major river basins: the Amazon, Congo, and Mekong rivers. Collectively, these basins hold approximately one-third of all freshwater fish species in the world, most of which are endemic to their respective river basin. The maintenance and sustainability of this biodiversity is threatened by the growing number of active and planned hydroelectric dams along major streams and smaller tributaries. Dams have been shown to effect the normal behavior of a river, physically trapping sediment behind it and therefore limiting nutrients further downstream, causing erosion and changing the types of available habitat for different aquatic species. From a human perspective, most local populations living along the river do not likely feel the benefits of these dams and may be displaced by the resulting reservoirs. Additionally, dams have been shown to detrimentally impact migratory fishes, even within the presence of fish passage devices. This has resulted in depletion of fish stocks which are negative for the ecosystem and hurt the local fishermen. The authors propose a holistic, basin-wide approach for the further approval and permitting of dams and suggest that greater care needs to taken during the planning phase to assess costs and benefits for all stakeholders. – Josh
Image via Allie Caulfield
Article – Balancing hydropower and biodiversity in the Amazon, Congo, and Mekong.
Citation – Winemiller, K. O., McIntyre, P. B., Castello, L., Fluet-Chouinard, E., Giarrizzo, T., Nam, S., … & Stiassny, M. L. J. (2016). Balancing hydropower and biodiversity in the Amazon, Congo, and Mekong. Science, 351(6269), 128-129.
Presenter – Josh Cullen