The satellite images, compared every two years, have enabled researchers to put together an extensive overview of the degradation of the forest along a 20-year timeline. The field research assessed scarring from burning, timber extraction and other disturbances. The combination of the two investigations resulted in the estimate of carbon stock available today.
Two regions were studied in loco: Santarm and Paragominas, in the eastern part of the Amazon region, both under strong degradation pressures. Two hundred twenty-five areas were investigated in these two regions.
"We collected data from more than 70,000 trees and took more than 5,000 samples of soil, dead wood and other components of what is known as carbon stock. It was the largest study conducted to date regarding carbon loss from tropical forests due to selective logging and wildfires," Ferreira said.
According to her, the research included four of the five functionally distinct carbon pools whose study is recommended by the United Nations (UN) Intergovernmental Panel on Climate Change (IPCC): aboveground biomass (live plants), dead organic matter, leaf litter (layer that contains a combination of fragments of leaves, branches and other decomposing organic matter) and soil (up to 30 centimeters (cm) in depth). "The only thing we didn't measure was the carbon stock in the roots," she said.
For comparative purposes, five categories of forest were considered: primary (totally intact) forest; forest affected by logging; forest affected by fires; forest affected by selective logging and fires; and secondary forests (regenerating after complete clearance).
The forests that were disturbed by logging or fire had from 18% to 57% less carbon than primary forests. One area of primary f
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Fundao de Amparo Pesquisa do Estado de So Paulo