A Look at Amazon Basin Seasonal Dynamics with the Biophysical ...

Spatial Pattern of Selective Logging, in an ageing Amazon frontier: the case of easternParáSanae Hyashi, Ane Alencar, Daniel NepstadSpatial determinants of logging activity in Amazon landscapes are important for predictingchanges in the forest sector, for estimating forest fire probability, and for improving enforcementof logging regulations. To identify the spatial determinants of logging, a multi-temporal analysis oflogging scars was conducted using Landsat ETM scenes (path/row 223/62) for an area of 32,340km 2 in eastern Pará between Paragominas and Tailândia, two important logging centers ineastern Amazon. Three consecutive years (1999-2001) of selectively logged areas were mappedusing a screen visual interpretation method for intercalibrated Landsat band five images. Theannual logging scars were defined by a strong soil response from the active wood decks. Thelogging scar maps were then overlaid to quantify the areas under consecutive logging,abandonment, and logged areas converted to pasture or agriculture. The spatial pattern of thelogging patches was identified based on the distance to paved and secondary roads, theprescence of sawmills and previously logged areas. In this old logging frontier, an average of52% of the area logged was abandoned to forest regrowth from 1999 to 2001, while 46% was relogged,and only 1 % was deforested in the following years. Most of the logged areas werelocated from one to five kilometers from secondary roads, and extended an average of threekilometers per year away from the nearby logging centers. The results of the study show a strongtendency for logging to take place within a one to three kilometers of the old logging scars.