About half of Brazil's original Amazon rainforest has been occupied by man, deforested or used for industry like logging and its destruction is worse than government data shows, a leading environmental group said on Tuesday.

The study using satellite photos shows that land occupation and deforestation covers some 47 percent of the world's largest jungle, an area bigger than the continental United States, the Brazilian non-government organization Imazon said.

The respected group has received funding from a series of sources including the Ford Foundation, the German and U.S. governments.

While Brazil's government says only 16 percent of Brazil's Amazon has been deforested, the Imazon study indicates a much larger area is threatened or being destroyed by man, researcher Carlos Souza said.

"This shows the real pressure on the forest," said Souza, who used satellite images up to 2002 to produce the study.

Deforestation of the Amazon hit its second-highest level ever last year as ranchers, farmers and loggers cleared an area larger than the U.S. state of New Jersey.

President Luiz Inacio Lula da Silva faces criticism from environmentalists that he is more interested in building roads and dams to drive Brazil's farm export-led economy than slow Amazon destruction.

Lula's government says it is using satellite monitoring, reserves and better law enforcement to slow destruction of an area that is home to ten percent of the world's fresh water and 30 percent of plant and animal species.

The center-left government is particularly concerned about an "arc of deforestation" that marks an agricultural and settlement frontier sweeping from east to west across the lower, southern half of the Amazon.

Imazon said its survey shows reserves must be created deep within the forest, as well as on the frontier of Brazil's portion of the Amazon -- about two thirds of the rainforest.

"Vast areas of forest that were previously considered empty (especially in the north and west areas) show signs of growing human pressure, especially from forest fires," the Imazon study said.

Brazilian Environment Ministry officials were not immediately available to comment on the survey.

Some 70 percent of Brazil's tropical savannah -- once the size of the Amazon -- has been deforested to create the world's biggest grain growing area, environmental groups say.

The Amazon will go the same way if agriculture, business and government use it as a resource to fuel economic growth, Silva said last week as she opened an environmental police academy.