NEAR AMARANTE DO MARANHAO , BRAZIL - JUNE 10: Cows graze in a deforested section of Amazon rainforest on June 10, 2012 near Amarante do Maranhao, Brazil. The cattle industry has taken over much of the deforested land in the Amazon. Although deforestation in the Brazilian Amazon is down 80 percent since 2004, environmentalists fear recent changes to the Forest Code will lead to further destruction. Around 20 percent of the rainforest has already been destroyed. The Brazilian Amazon, home to 60 percent of the world’s largest forest and 20 percent of the Earth’s oxygen, remains threatened by the rapid development of the country. The area is currently populated by over 20 million people and is challenged by deforestation, agriculture, mining, a governmental dam building spree, illegal land speculation including the occupation of forest reserves and indigenous land and other issues. Over 100 heads of state and tens of thousands of participants and protesters will descend on Rio de Janeiro, Brazil, later this month for the Rio+20 United Nations Conference on Sustainable Development or 'Earth Summit'. Host Brazil is caught up in its own dilemma between accelerated growth and environmental preservation. The summit aims to overcome years of deadlock over environmental concerns and marks the 20th anniversary of the landmark Earth Summit in Rio in 1992, which delivered the Climate Convention and a host of other promises. Brazil is now the world’s sixth largest economy and is set to host the 2014 World Cup and 2016 Summer Olympics. (Photo by Mario Tama/Getty Images) Mario Tama / Getty Images

PARA STATE, BRAZIL - JUNE 11: A lone remaining Amazon rainforest tree stands in a deforested section of Amazon rainforest on June 11, 2012 in Para state, Brazil. Although deforestation in the Brazilian Amazon is down 80 percent since 2004, environmentalists fear recent changes to the Forest Code will lead to further destruction. Around 20 percent of the rainforest has already been destroyed. The Brazilian Amazon, home to 60 percent of the world’s largest forest and 20 percent of the Earth’s oxygen, remains threatened by the rapid development of the country. The area is currently populated by over 20 million people and is challenged by deforestation, agriculture, mining, a governmental dam building spree, illegal land speculation including the occupation of forest reserves and indigenous land and other issues. Over 100 heads of state and tens of thousands of participants and protesters will descend on Rio de Janeiro, Brazil, later this month for the Rio+20 United Nations Conference on Sustainable Development or 'Earth Summit'. Host Brazil is caught up in its own dilemma between accelerated growth and environmental preservation. The summit aims to overcome years of deadlock over environmental concerns and marks the 20th anniversary of the landmark Earth Summit in Rio in 1992, which delivered the Climate Convention and a host of other promises. Brazil is now the world’s sixth largest economy and is set to host the 2014 World Cup and 2016 Summer Olympics. (Photo by Mario Tama/Getty Images) Mario Tama / Getty Images

RIO DE JANEIRO, BRAZIL - JUNE 14: Youth from around the world gather at the camp on the campus of the UFRJ in Red Beach. They stand against the way decisions are deliberated at Riocentro and prestige to the Peoples' Summit, an event that promotes social and environmental justice at Rio +20, on June 14, 2012 in Rio de Janeiro, Brazil. (Photo by Buda Mendes/LatinContent/Getty Images) Buda Mendes/STF / LatinContent/Getty Images

NEAR ALTAMIRA, BRAZIL - JUNE 15: Construction continues at the Belo Monte dam complex in the Amazon basin on June 15, 2012 near Altamira, Brazil. Belo Monte will be the world’s third-largest hydroelectric project and will displace up to 20,000 people while diverting the Xingu River and flooding as much as 230 square miles of rainforest. The controversial project is one of around 60 hydroelectric projects Brazil has planned in the Amazon to generate electricity for its rapidly expanding economy. While environmentalists and indigenous groups oppose the dam, many Brazilians support the project. The Brazilian Amazon, home to 60 percent of the world’s largest forest and 20 percent of the Earth’s oxygen, remains threatened by the rapid development of the country. The area is currently populated by over 20 million people and is challenged by deforestation, agriculture, mining, a governmental dam building spree, illegal land speculation including the occupation of forest reserves and indigenous land and other issues. Over 100 heads of state and tens of thousands of participants and protesters will descend on Rio de Janeiro, Brazil, later this month for the Rio+20 United Nations Conference on Sustainable Development or ‘Earth Summit’. Host Brazil is caught up in its own dilemma between accelerated growth and environmental preservation. (Photo by Mario Tama/Getty Images) Mario Tama / Getty Images

ALTAMIRA, BRAZIL - JUNE 15: Protesters demonstrate against the Belo Monte dam project near the area where the dam complex is under construction in the Amazon basin on June 15, 2012 in Altamira, Brazil. Belo Monte will be the world’s third-largest hydroelectric project and will displace up to 20,000 people while diverting the Xingu River and flooding as much as 230 square miles of rainforest. The controversial project is one of around 60 hydroelectric projects Brazil has planned in the Amazon to generate electricity for its rapidly expanding economy. While environmentalists and indigenous groups oppose the dam, many Brazilians support the project. The Brazilian Amazon, home to 60 percent of the world’s largest forest and 20 percent of the Earth’s oxygen, remains threatened by the rapid development of the country. The area is currently populated by over 20 million people and is challenged by deforestation, agriculture, mining, a governmental dam building spree, illegal land speculation including the occupation of forest reserves and indigenous land and other issues. Over 100 heads of state and tens of thousands of participants and protesters will descend on Rio de Janeiro, Brazil, later this month for the Rio+20 United Nations Conference on Sustainable Development or ‘Earth Summit’. Host Brazil is caught up in its own dilemma between accelerated growth and environmental preservation. (Photo by Mario Tama/Getty Images) Mario Tama / Getty Images

A Kaiapo Indian takes pictures of fellow tribesmen during an exhibition of their traditional games at Kari-Oca village, where indigenous groups are staying during the Rio+20 United Nations Conference on Sustainable Development in Rio de Janeiro, Brazil, Sunday, June 17, 2012. The Earth summit runs through June 22. (AP Photo/Victor R. Caivano) Victor R. Caivano / AP

Indigenous squeeze into a subway train as they ride to the People's Summit for Social and Environmental Justice in defense of the commons, a parallel event taking place alongside the United Nations Conference on Sustainable Development, or Rio+20, in Rio de Janeiro, Brazil, Monday June 18, 2012. The Earth summit runs through June 22, with three final days of high-profile talks among some 130 top leaders from nations around the globe. (AP Photo/Felipe Dana) Felipe Dana / AP

Brazilian Army soldiers patrol along Copacabana beach as the United Nations Conference on Sustainable Development, or Rio+20, goes into its third day, in Rio de Janeiro, Brazil, Friday June 15, 2012. The Earth summit runs through June 22, with three final days of high-profile talks among some 130 top leaders from nations around the globe. (AP Photo/Felipe Dana) Felipe Dana / AP

A man representing death holds a globe during a protest outside the People's Summit for Social and Environmental Justice in defense of the commons, a parallel event taking place alongside the United Nations Conference on Sustainable Development, or Rio+20, in Rio de Janeiro, Brazil, Friday, June 15, 2012. (AP Photo/Silvia Izquierdo) Silvia Izquierdo / AP

An indigenous man takes a picture during the People's Summit for Social and Environmental Justice in defense of the commons, a parallel event taking place alongside the United Nations Conference on Sustainable Development, or Rio+20, in Rio de Janeiro, Brazil, Friday, June 15, 2012. (AP Photo/Silvia Izquierdo) Silvia Izquierdo / AP

A Bororo tribe member competes in the archery event at the "Jogos Verdes," or Green Games, in the Kari-Oca village where indigenous groups are staying during the United Nations Conference on Sustainable Development, or Rio+20, in Rio de Janeiro, Brazil, Friday June 15, 2012. The Earth summit runs through June 22. (AP Photo/Felipe Dana) Felipe Dana / AP

Activists deploy a banner at the Copacabana beach in Rio de Janeiro, Brazil, Sunday, June 17, 2012. The banner calls on Rio+20 leaders to deliver a new plan to shift nearly $1 trillion spent each year on fossil fuel subsidies to renewable energy and sustainable development.(AP Photo/Silvia Izquierdo) Silvia Izquierdo / AP

A man walks past a replica of the Statue of Liberty outside the People's Summit for Social and Environmental Justice in defense of the commons, a parallel event taking place alongside the United Nations Conference on Sustainable Development, or Rio+20, in Rio de Janeiro, Brazil, Sunday June 17, 2012. (AP Photo/Felipe Dana) Felipe Dana / AP

Brazilian artist Siron Franco previews his video installation, "Brasil Cerrado" or Brazilian Savannah, that is part of an art exhibit leading up to the Rio+20 Earth summit, in Rio de Janeiro, Brazil, Monday June 11, 2012. Franco's warns about the deforestation of the savannah that contains a third of Brazil's biodiversity. (AP Photo/Felipe Dana) Felipe Dana / AP