The National Institute for Space Research says satellite imagery shows nearly 2,300 square kilometers (900 square miles) were destroyed in the 12 months through July 31, a 48 percent drop from a year earlier.
But Environment Minister Izabella Teixeira stressed Tuesday that the numbers aren't final. He said researchers first must closely examine images in which there was significant cloud cover.
The government credits better enforcement of environmental laws for slowing deforestation. But environmental groups contend it is only a temporary lull because of the global financial crisis.
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