Thanks to Jon Sealy who reports from his web-log on a BBC story about Brazil's giving the green light to the construction of two dams along the Amazon's largest tributary, the Madeira River.
Good news: it's for hydroelectric (that is, relatively clean energy) for Brazil's expanding energy needs. Bad news, from the article: "The river is said to have one of the most diverse fish stocks in the world."
Plus there's the inevitable failing of all dams due to sediment. Sheesh. Good luck, Amazon.