Forest degradation, which includes the selective removal of wood, the setting of fires that create minimal damage, and the cutting of virgin forest in small fragments, already affect a larger area of the Brazilian Amazon than deforestation itself, according to one new search.
In the period analyzed by the study team, which runs from 1992 to 2014, it is estimated that the area of degraded forests reached 337 thousand km2, against 308 thousand km2 of deforestation. Moreover, the impact of degradation seems to spread more easily to relatively remote points of the Amazon territory, far from the so-called arc of deforestation, in which the devastation of the forest is more intense.
The research is in the latest edition of the American magazine Science, one of the most important in the world.
“It is necessary to stop seeing the issue of changes in land use in the Amazon as something that is just deforestation. There is more going on, and this article helps to show that,” says geographer Marcos Antonio Pedlowski, from Uenf, one of the co-authors of the work.
The team, coordinated by Eraldo Matricardi of UnB, combined satellite data, and field validations to capture, from above, the general picture of forest degradation in the Amazon. This is possible because, even in areas where the canopy has not been removed (that is, the highest layer of trees in the forest, which can be seen from above), the forest images have a different visual “signature” if it is degraded.
“In the case of the effects of fire, the detection of this is reasonably automatic. Selective cutting is more difficult,” says Matricardi.
Translated by Kiratiana Freelon