The forest biome of Amazonia is one of Earth's greatest biological treasures and a major component of the Earth system. This century, it faces the dual threats of deforestation and stress from climate change. In this article, the authors summarize some of the latest findings and thinking on these threats, explore the consequences for the forest ecosystem and its human residents, and outline options for the future of Amazonia.

Agricultural expansion, opening of new roads and migration of people to unexploited areas are all major causes of Amazon deforestation; thus many sectors share the responsibility for reversing it.

The United States is the world's leading producer of soy. However many U.S. farmers are shifting from soy to corn in order to qualify for generous government subsidies intended to promote biofuel production. The rising price for soy has important consequences for Amazonian forests and savanna woodlands. (Letters)

Many species of trees in the Amazon rainforests, and animals that depend on them are disappearing more rapidly than previously thought, an international research team reported recently. Led by

The endangered Nukak-Mak

Since the energy shortage in 2001, there has been renewed interest in energy-generation projects in Brazil. Policy options under consideration include expansion of natural gas exploration and hydropower generation in the Amazon. This article analyzes environmental opposition to two projects, the Urucu pipeline and the Belo Monte Dam. Despite significant environmental and social costs, development of energy resources is a critical political issue.