Damming the Amazon

Increasing demands for energy are putting the world's rivers at risk. Hydroelectric projects are responsible for flooding vast areas of rainforest. The decay of forest wood add more greenhouse gases to the atmosphere contributing to global warming. This flooding means that terrestrial species, including humans, must migrate to new areas usually leading to more deforestation. Fish species adapted to the riverine environment must adapt to lake conditions or perish. Dams disrupt the migration of species which move up or down-river to spawn.

Burmese Erosion - Courtesy of NASA

Erosion is a well-known result of deforestation with serious consequences for river commerce and river life. Sediments build up creating sandbars and shallows, interfering with river transportation. Similarly, sediment build-up reduces the effectiveness of existing hydroelectric projects. Erosion and the resulting decline in water clarity causes downstream mayhem for offshore coral reefs. River inhabitants also suffer due to the reduced water clarity. Species that rely primarily on sight decline the most, while the increased amount of suspended particles interferes with fish gills. Erosion inhibits plant growth and hinders the development of fish eggs.

Overfishing is a problem that plagues the world's oceans (35-60% are overfished worldwide) and rainforest waters. Regional declines in catch have been reported throughout the Amazon. The loss of certain species responsible for seed dispersal will have a negative effect on the renewal of the rainforest.

Poisoning from spills and pollution from industrial processes, mining, and sewage continue to reduce the diversity of rainforest waters, in addition to affecting human populations. The much publicized spill on the Essequibo river, along with the continued spilling of oil in Peru and Ecuador, has had a large impact of river life.

Article on the effects of mercury in aquatic habitats (mercury pollution in the Amazon frequently results from mining activities).