Brazil and the World Bank signed an agreement in Johannesburg yesterday on the sidelines of the summit to triple the area of Amazonian rainforest which is protected.
The protected area of the disastrously over-exploited forest immediately rose to 50 million hectares (120 million acres), 3.6 per cent of the world's tropical forests.
"Saving the forest is crucial for sustainable development," the theme of the summit, said Brazilian president Mr Fernando Henrique Cardoso.
He said the agreement was the biggest project yet to save the forest and Brazil's greatest success at the summit.
The programme's $395 million cost will be shared by the Brazilian government, the private sector and international agencies.
The jungle region contains one-third of the biodiversity of the Earth, including the world's largest freshwater source: 350 species of mammals, 950 different types of birds, 2,000 types of fish and 2.5 million different types of insect.
Surveillance is carried out by the new Amazon Surveillance System, known as SIVAM, which already monitors an area of 2.12 million square miles, about the size of western Europe.
It alerts the authorities to incursions from neighbouring countries, particularly Colombia, where guerrillas fighting a civil war have clashed with Brazilian troops.
More than 4,000 Brazilian soldiers and sailors, equipped with amphibious tanks, patrol boats and helicopters, are posted along the border.
The system, based in Brasilia, also has five radar aircraft and 25 fighter jets at its disposal.
The system's 120 "eyes" help to protect the Amazon environment by better monitoring deforestation, illegal exploitation of protected substances, and violence against indigenous tribes.
The rate of destruction of the Amazon between 1995 and 2000 returned to the same levels of that between 1970 and 1980. This was at 4.7 million acres a year, according to a study of satellite photographs and Brazil's National Amazon Research Institute.
In 2001, deforestation fell 3.4 per cent, when 3.9 million acres were destroyed - (AFP)