| Deforestation in tropical forests and its consequences on global climate change have been monitored using remotely sensed data. Most of the currently available land cover maps show only those sites where trees have been completely removed. Just a few attempts to detect forest areas where trees were partially removed, as in the case of selective logging, have been done. This study assesses forest impacts by selective logging and extend current multi-annual Amazon-wide land use classification to include selectively logged forests in addition to the more frequently used thematic classes (forest, deforestation, regrowth, cerrado, and water body). Remotely sensed data combined with field studies, Geographic Information Systems (GIS), and related techniques were applied in this research. This is the first multi-temporal assessment of selective logging in the Brazilian Amazon in which I estimated that at least 5980, 10064, and 26085 Km2 of forest had been logged by 1992, 1996, and 1999, respectively. I also estimated that at least 3689, 5107, and 11638 Km2 had been actively logged in 1992, 1996, and 1999, respectively. Finally, I found that at around of 10% of former logging areas detected in between 1992 and 1996 was revisited or logged again in 1999. I also observed that 13% of logged forests in 1992 were deforested by 1996, an additional 15% by 1999, and 11% of forests logged in 1996 were deforested by 1999. |
